ISMRM 21st Annual Meeting & Exhibition 20-26 April 2013 Salt Lake City, Utah, USA

3362 -3385 Breast: Clinical, Technical & Treatment Response
3386 -3409 Prostate
3410 -3433 Preclinical MR of Cancer: Cells & Animals
3434 -3456 Cancer

Tuesday, 23 April 2013 (10:00-11:00) Exhibition Hall
Breast: Clinical, Technical & Treatment Response

  Computer #  
3362.   1 An Automatic Template-Based Breast Segmentation Method for Fat-Suppressed MRI
Xiaoyong Wang1, Muqing Lin1, Peter T. Fwu1, Ling-Chuan Chang2, Yi-Ting Wu2, Chin-Yu Chang2, Jeon-Hor Chen3, and Min-Ying Su1
1Center for Functional Onco-Imaging, University of California, Irvine, CA, United States, 2Department of Radiology, China Medical University Hospital, Taichung, Taiwan, 3Center for Functional Onco-Imaging, University of California Irvine, Irvine, CA, United States

The purpose is to develop an automatic breast segmentation method for fat-suppressed MRI. The algorithm is based on template matching of chest region using nonrigid registration. The body landmarks defined on the template can be transformed to the subject’s space to determine the posterior-lateral boundary of the breasts. The results show that this chest template-based method is robust for different body and breast shapes, with a mean error of 5.4% for breast, and 2.7% for fibroglandular tissue segmentation. This tool can help developing computer-aided-diagnosis method for breast cancer detection, as well as quantitative analysis of breast density for risk management.

3363.   2 A 3D Shape and Textural Classification Tool for Identifying Malignant Breast Cancer
Rebecca E. Thornhill1, Greg O. Cron2, Kevin Ibach1, Shilpa Lad1, Mark E. Schweitzer1, and Jean Seely1
1Medical Imaging, The Ottawa Hospital, Ottawa, Ontario, Canada, 2Medical Imaging, Ottawa Hospital Research Institute, Ottawa, Ontario, Canada

While breast MRI has shown tremendous promise for characterizing breast cancers, its specificity has been limited by reliance on tumor shape. Many tumors will exhibit discrete areas of high perfusion or vascular leakiness. These ‘hot spots’ could yield important information that would be obscured by reporting the average tumor Ktrans. In this study, we have identified a potential recipe for predicting malignant breast cancer comprising of shape and textural features. While textural features appear to provide good specificity and modest sensitivity, the converse was true for shape-based models. With further optimization, this approach may improve accuracy compared to conventional MRI.

3364.   3 Association of Lesion and Background Parenchyma in Diagnostically Challenging Breast Lesions
Ana Paula Klautau Leite1,2, Melanie Freed1, Melanie Moccaldi3, Kai Tobias Block4, Amy Melsaether3, Alana Amarosa3, Sungheon Kim1, and Linda Moy3
1Radiology, Center for Biomedical Imaging, New York Universiy School of Medicine, New York, New York, United States, 2Radiology, Hospital das Clinicas- FMUSP, School of Medicine - University of Sao Paulo, Sao Paulo, SP, Brazil, 3Radiology, Cancer Institute, New York University School of Medicine, New York, New York, United States, 4Radiology, NYU Langone Medical Center, New York, New York, United States

The relationship between a lesion in the breast and its effect on contrast uptake kinetics in the breast parenchyma (PS) is unclear. This study investigated whether the quantitative analysis of MR contrast-enhancement kinetics of BP and lesions improves our ability to discriminate between benign and malignant tumors. We analyzed 102 lesions using a linear principal component analysis (PCA) and found that we can correctly identify benign lesions compared to malignant lesions by quantitatively comparing its enhancement with the adjacent BP. We almost reached statistical significance when performing the same analysis on malignant lesions.

3365.   4 Age Correlation of Background Breast Tissue Enhancement Measured from the Entire Segmented Fibroglandular Tissue and the Hot-Spot in DCE-MRI
Xiaoyong Wang1, Jeon-Hor Chen2, Christine Hsu2, Shadfar Bahri1, Hon J. Yu1, Peter T. Fwu1, Muqing Lin1, and Min-Ying Su1
1Center for Functional Onco-Imaging, University of California, Irvine, CA, United States, 2Center for Functional Onco-Imaging, University of California Irvine, Irvine, CA, United States

This work analyzed the background breast tissue enhancement in the contralateral normal breast of patients diagnosed with breast cancer. A computer program is used to segment the entire fibroglandular tissue, and a kernel of 3 by 3 pixels is used to search the hot spot. The hotspot enhancement is 2 fold higher compared to the mean background tissue enhancement. A negative correlation with age was found (r=0.35 for hotspot, r=0.33 for mean tissue enhancement). The presented method may be used to evaluate the role of background tissue enhancement as a risk factor in development of contralateral breast cancer.

3366.   5 Comparative Measurement of Breast Volume and Dense Tissue Volume Based on Breast MRI and Low Dose Chest CT
Xiaoyong Wang1, Jeon-Hor Chen2, Yen-Hsiu Liao3, Peter T. Fwu1, Muqing Lin1, and Min-Ying Su1
1Center for Functional Onco-Imaging, Department of Radiological Sciences, University of California, Irvine, CA, United States, 2Center for Functional Onco-Imaging, Department of Radiological Sciences, University of California Irvine, Irvine, CA, United States, 3Department of Radiology, China Medical University Hospital, Taichung, Taiwan

We reported a breast density segmentation method for low dose chest CT, which is widely used for lung cancer screening. The method was based on algorithms used for MRI segmentation (FCM clustering and region growing & fitting). Fifteen healthy subjects who received both CT for lung cancer screening and MRI for breast cancer screening were analyzed. The breast volume, fibroglandular tissue volume, and percent density measured on CT and MRI were highly correlated, with r > 0.98. The results show that it is feasible to segment breast density based on chest CT to yield consistent measurements compared to MRI.

3367.   6 Agreement Between Quantitative and Radiologist-Assessed Qualitative Background Parenchymal Breast Enhancement at MRI
Ania Azziz1, Ella Jones1, Catherine Klifa1, David C. Newitt1, Elissa Price1, Nola M. Hylton2, and Bonnie N. Joe1
1Radiology, UCSF, San Francisco, CA, United States, 2Radiology, University of California San Francisco, San Francisco, CA, United States

Breast MRI background parenchymal enhancement (BPE) can interfere with MRI interpretation and is associated with breast cancer risk. The purpose of this study is to define whole breast BPE using an accurate quantitative method in a normal population and compare this quantitative measure to radiologist-assessed qualitative enhancement in order to facilitate understanding of BPE. Quantitative BPE in the normal population does not exceed 57%. Additionally, quantitative and qualitative BPE are significantly correlated, however, qualitative BPE trends towards higher values. These findings serve as benchmark data for accurate quantitative values of MR BPE in normal patients.

3368.   7 Clinical 7 Tesla Contrast-Enhanced Breast MRI -permission withheld
Bertine L. Stehouwer1, Wouter B. Veldhuis1, Michel Italiaander1, Vincent Oltman Boer1, Peter R. Luijten1, Maurice A.A.J. van den Bosch1, and Dennis W.J. Klomp1
1Radiology, University Medical Center Utrecht, Utrecht, Netherlands

Breast imaging at 7.0 Tesla offers new diagnostic possibilities that have the potential to improve staging and follow-up of breast cancer patients. In this abstract we show that bilateral contrast-enhanced breast MRI at 7.0 Tesla is feasible for clinical implementation meeting the standards of the clinically applied BI-RADS-MRI criteria.

3369.   8 SWIFT Dual Breast Imaging Sequence and Coil with Interleaved Adiabatic Fat Suppression
Curtis Andrew Corum1, Djaudat Idiyatullin1, Angela Snyder1, Carl Snyder1, Diane Hutter1, Lenore Everson1, Lynn E. Eberly2, Michael Nelson3, and Michael Garwood1
1CMRR, Radiology, University of Minnesota, Minneapolis, MN, United States, 2Biostatistics, University of Minnesota, Minneapolis, MN, United States, 3Breast Center, Radiology, University of Minnesota, Minneapolis, MN, United States

We describe an optimized protocol for dual breast imaging with SWIFT. Unique solutions to issues such a transmit/receive uniformity and coverage, fat suppression are discussed.

3370.   9 BreastVIEW: Isotropic 3D High Resolution T2-Weighted Breast Imaging at 7T
Ivan E. Dimitrov1,2, Ananth J. Madhuranthakam3, Sergey Cheshkov2, Stephen Seiler3, Sally Goudreau3, Joseph Rispoli4, Mary P. McDougall4, Steven M. Wright4, and Craig R. Malloy2,3
1Philips Medical Systems, Highland Heights, OH, United States, 2Advanced Imaging Research Center, University of Texas Southwestern Medical Center, Dallas, TX, United States, 3Radiology, University of Texas Southwestern Medical Center, Dallas, TX, United States, 4Biomedical Engineering, Texas A&M University, College Station, TX, United States

The ability to accurately classify breast lesions by MRI depends intimately on the ability to generate high resolution images with sharp margins and little blurring. Taking advantage of the increased spatial resolution afforded at 7T requires alleviation of the blurring caused by decrease in tissue T2 at this high field. An optimized modulated refocusing echo train that accounts for breast parenchymal tissue-specific T1 and T2 can generate signal plateaus that remain constant even for long refocusing trains, thus resulting in sharper point spread function. We present isotropic high-resolution 3D T2-weighted breast imaging at 7T (BreastVIEW) with improved edge detection.

3371.   10 Fast Bilateral Breast Coverage with SENSE-Accelerated High Spectral and Spatial Resolution (HiSS) MRI
Milica Medved1, Hiroyuki Abe1, Gillian M. Newstead1, Marko K. Ivancevic2, Olufunmilayo I. Olopade3, and Gregory S. Karczmar1
1Radiology, University of Chicago, Chicago, Illinois, United States, 2Philips Healthcare, Cleveland, Ohio, United States, 3Medicine, University of Chicago, Chicago, Illinois, United States

A new technical development implements SENSE imaging to high spatial and spectral resolution (HiSS) MRI, via a software patch, allowing fast bilateral breast MR imaging with increased in-plane resolution. This opens up new applications, such as non-contrast screening and breast density measurement for breast cancer risk assessment.

3372.   11 Towards the Investigation of Breast Tumor Malignancy Via Electric Conductivity Measurement
Ulrich Katscher1, Hiroyuki Abe2, Marko K. Ivancevic3, Karim Djamshidi1, Philipp Karkowski1, and Gillian M. Newstead2
1Philips Research Europe, Hamburg, Germany, 2Medical Center, University of Chicago, Chicago, Illinois, United States, 3MR Clinical Science, Philips Healthcare, Cleveland, Ohio, United States

According to ex vivo studies, breast tumors exhibit a significantly altered electric conductivity. This feature opens the chance to increase the specificity of breast tumor characterization with MRI. The electric conductivity can be measured in vivo using “Electric Properties Tomography” (EPT). Due to the complex frayed structure of fat and ductile tissue in the breast, an EPT reconstruction algorithm dedicated for breast tissue was developed, which is applied in this study to eight breast cancer patients. The study tries to contribute to the discussion if breast tumor conductivity can be measured reliably with EPT, aiming for future tumor malignancy staging.

3373.   12 Diffusion Tensor Imaging (DTI) at Multiple Diffusion Times in Mammary Fibroglandular Tissue and Cancerous Lesions
Gene Young Cho1,2, Ana Paula Klautau Leite3, Steven Baete3, Daniel K. Sodickson3, Sungheon Kim3, Linda Moy4, and Eric E. Sigmund3
1Radiology - Center for Biomedical Imaging, New York University, New York, NY, United States, 2Sackler Institute of Graduate Biomedical Sciences, New York University School of Medicine, New York, NY, United States, 3Radiology - Center for Biomedical Imaging, New York University School of Medicine, New York, NY, United States, 4Radiology - Cancer Institute, New York University School of Medicine, New York, NY, United States

Diffusion tensor imaging (DTI) provides microstructural biomarkers reflecting diffusion anisotropy. DTI has been shown to probe anisotropic diffusion in the ducts of mammary fibrograndular tissue (FGT) and its disruption in breast cancer lesions. We explored the use of longer diffusion times to increase apparent restriction and enhance distinction between mammary FGT and lesion tissue. We collected stimulated echo DTI at two diffusion times (30 ms and 520 ms) in FGT and cancerous lesions and compared DTI measurements with typical clinical radiological data. Results indicate significantly higher FGT anisotropy at higher diffusion times and slightly increased lesion / FGT distinction.

3374.   13 Contrast-Enhanced MRI of the Breast at 7 and 3 T in the Same Patients: Inital Experience
Katja Pinker-Domenig1, Pascal Baltzer1, Wolfgang Bogner2, Stephan Gruber2, Lenka Minarikova2, Olgica Zaric2, Doris Leithner1, Siegfried Trattnig2, and Thomas Helbich3
1Dept. of Radiology, Division of Molecular and Gender Imaging, Medical University Vienna, Vienna, Austria, 2Dept. of Radiology, MR Centre of Excellence, Medical University Vienna, Vienna, Austria, 3Dept. of Radiology, Division of Molecular and Gender Imaging, Medical University of Vienna, Vienna, Austria

To compare contrast–enhanced high resolution MRI of the breast at 3 and 7Tesla. Two readers independently assessed image quality, lesions conspicuity and lesion morphology and enhancement-kinetics of 25 malignant lesions and 12 benign lesions in 20 patients. 3T MRI had a sensitivity 96.2% and a specificity of 91.7%. 7T had a sensitivity of 100% and a specificity of 84.6% (reader1) and 91.7% (reader2). 7T MRI of the breast is clinically applicable with an excellent diagnostic accuracy and inter-reader agreement. Overall image quality was equal to 3T but a higher spatial resolution was achieved at 7T.

3375.   14 Impact of TWIST View Sharing on Lesion Enhancement Profile in Dynamic Breast MRI
Yuan Le1, Randall Kroeker2, Christian Geppert3, Brian M. Dale4, Hal D. Kipfer1, and Chen Lin1
1Radiology and Imaging Science, Indiana University School of Medicine, Indianapolis, IN, United States, 2Siemens Medical Solutions, Winnipeg, Manitoba, Canada, 3Siemens Medical Systems, New York, NY, United States, 4MR R&D, Siemens Medical Solutions, Morrisville, North Carolina, United States

A simulation study was conducted to investigate the impact of TWIST view sharing on the dynamic breast MRI. A digital ‘phantom’ was generated with spherical lesions of 3-9 mm diameter which exhibit wash-out type of contrast uptake. View sharing strategy, view order and acquisition parameters were identical to actual TWIST sequence and the typical clinical application. The results suggest that, with the same temporal resolution, backward TWIST view sharing provides the best result in tumor edge profile and dynamic enhancement evaluation.

3376.   15 Spectrally Selective Excitation for Improved DWI, APT and MRS of the Breast
He Zhu1, Lori R. Arlinghaus1, John C. Gore1, and Thomas E. Yankeelov1
1Radiology, Vanderbilt University, Nashville, TN, United States

Lipid suppression is an area where proven approaches in the brain often fail because of more heterogeneous water-fat distribution in the breast. Here, we present our initial experience combining spectrally selective excitation with DWI, APT and MRS in the breast. Our preliminary results demonstrated water only excitation as a feasible alternative to existing methods of fat suppression with a moderate increase in echo time.

3377.   16 Comparison of Morphological and Functional Imaging in Tumour Response Evaluation in Patients with Locally Advanced Breast Cancer Receiving Neoadjuvant Chemotherapy
Karthik Panchanatheeswaran1, Rajinder Parshad1, Rani G. Sah2, Uma Sharma2, Naranamangalam R. Jagannathan2, Vurthaluru Seenu1, Raju Sharma3, and Sanjay Thulkar3
1Department of Surgical Disciplines, All India Institute of Medical Sciences, New Delhi, Delhi, India, 2Department of NMR & MRI Facility, All India Institute of Medical Sciences, New Delhi, Delhi, India, 3Department of Radiodiagnosis, All India Institute of Medical Sciences, New Delhi, Delhi, India

In patients with locally advanced breast cancer undergoing neoadjuvant chemotherapy pathological complete response is the ultimate goal as it strongly correlates with a favorable prognosis. In this study we compared clinical examination, morphological imaging (mammography, USG, and MRI) and functional imaging (color Doppler, DW-MRI, MR T-SI curve and MR spectroscopy) in evaluating tumor response. We found that MRI has the maximum specificity to predict pCR and has highest reliability for predicting residual tumour size. The functional imaging can supplement morphological imaging modalities in predicting tumour responses to chemotherapy and may have a promising role in future in tumour response evaluation.

3378.   17 Treatment Response Monitoring in Breast Cancer Patients Undergoing Neoadjuvant Chemotherapy and Association of Total Choline with Receptor Status: A Feasibility Study Using Serial 3D High-Speed MR Spectroscopic Imaging and Dynamic Contrast Enhanced MR Imaging at 3 Tesla
Stefan Posse1,2, Tongsheng Zhang1, Melanie E. Royce2,3, Zoneddy Ruiz Dayao2,3, Susan Lopez2, Laurel Sillerud4, Claudia Wuillma Narvaez Villarrubia5, Steven Eberhardt2,6, Lesley Carol Lomo2,7, Ashwani Rajput2,8, John Russell2,8, Linda Casey9, and Patrick J. Bolan10,11
1Neurology, University of New Mexico, Albuquerque, NM, United States, 2UNM Cancer Center, University of New Mexico, Albuquerque, NM, United States,3Medical Oncology, University of New Mexico, Albuquerque, NM, United States, 4Biochemistry, University of New Mexico, Albuquerque, NM, United States,5Center for Emerging Energy Technology, University of New Mexico, Albuquerque, NM, United States, 6Radiology, University of New Mexico, Albuquerque, NM, United States, 7Pathology, University of New Mexico, Albuquerque, NM, United States, 8Surgery, University of New Mexico, Albuquerque, NM, United States,9Radiology, Nex Mexico Cancer Center, Albuquerque, NM, United States, 10Center for Magnetic Resonance Research, University of Minnesota, Minnesota, MN, United States, 11Radiology, University of Minnesota, Minnesota, MN, United States

Thirteen patients with biopsy-confirmed, infiltrating ductal carcinoma were studied at 3 Tesla to monitor changes in total Choline during neoadjuvant therapy in comparison with dynamic contrast enhanced (DCE) MRI, and to investigate association of total Choline with receptor status. 3D lipid suppressed Proton-Echo-Planar-Spectroscopic-Imaging (PEPSI) was performed with 1 cc voxel size using a 10 min scan protocol that included a water reference scan. Decreases in concentration and/or volume of total Choline preceded the decreases in tumor volume measured with DCE-MRI in 4 of the 6 patients followed during neoadjuvant therapy. The concentration and spatial extent of total Choline was more strongly elevated in triple negative tumors compared to non-triple negative tumors and not detectable in triple positive tumors.

3379.   18 Predicting Malignancy in High-Risk Breast Cancer Patients: Evaluating Diagnostic Accuracy of Pre-Treatment Contrast-Enhanced MRI
Yousef Mazaheri1, Charles W. Fry2, Sandra B. Brennan2, and Elizabeth A. Morris2
1Medical Physics, Memorial Sloan-Kettering Cancer Center, New York, NY, United States, 2Radiology, Memorial Sloan-Kettering Cancer Center, New York, NY, United States

To evaluate three empirical parametric models of enhancement (Liner-slope model, Ricker model, and Gamma-variate model) fitted to normalized contrast-enhanced magnetic resonance imaging (CE-MRI) data to better stratify risk in high-risk breast cancer patients.

3380.   19 Quantitative DCE-MRI Assessment of Breast Cancer Therapeutic Response: How Long Is the Acquisition Time Necessary?
Mohan L. Jayatilake1, Xin Li1, Alina Tudorica1, Karen Oh1, Nicole Roy1, Stephen Chui1, and Wei Huang1
1Oregon Health & Science University, Portland, OR, United States

Breast cancer patients underwent DCE-MRI studies before, after first cycle, at midpoint, and after completion of neoadjuvant chemotherapy. Ktrans and kep after first therapy cycle and their % changes (relative to baseline) provide early discrimination of pathologic complete responders (pCRs) from non-pCRs. Representative 10-min long DCE-MRI data from one pCR and one non-pCR were reprocessed with simulated acquisition time as short as ~ 3 min. It was found that DCE-MRI acquisition time of 5-6 min is sufficient for the purpose of early prediction of therapy response. Shorter DCE-MRI protocol reduces patient discomfort and minimizes motion artifacts.

3381.   20 Is Assessment of Breast Tumors with the Sole Use of DWI Sufficient for Breast Cancer Diagnosis?
Pascal Baltzer1, Wolfgang Bogner2, Hubert Bickel1, Olgica Zaric2, Thomas Helbich3, Georg Wengert1, and Katja Pinker-Domenig1
1Dept. of Radiology, Divison of Molecular and Gender Imaging, Medical University Vienna, Vienna, Vienna, Austria, 2MR Centre of Excellence, Medical University Vienna, Vienna, Vienna, Austria, 3Dept. of Radiology, Divison of Molecular and Gender Imaging, Medical University of Vienna, Vienna, Vienna, Austria

To solely apply DWI to a non-selected group of MRI patients and to compare its diagnostic accuracy to ceMRI in a multi-reader study. 60 consecutive patients with an imaging abnormality were included in this retrospective IRB approved study. Two experienced readers trained in different institutions independently read DWI and CE-MRI examinations and assigned a diagnosis (BIRADS scale 1=no lesion to 5= definite malignancy). Sensitivity, specificity, diagnostic accuracy and inter-reader variability (kappa statistics) were calculated for both readers. DWI for breast cancer diagnosis in breast MRI is feasible with a comparable sensitivity equal to ceMRI.

3382.   21 Association of Apparent Diffusion Coefficient with Molecular Biomarkers (ER, PR, HER2 Status) in Invasive Breast Cancer Patients Using Diffusion Weighted MR Imaging
Naranamangalam R. Jagannathan1, Rani G. Sah1, Uma Sharma1, Rajinder Parshad2, Vurthaluru Seenu2, and Sandeep Mathur3
1Department of NMR & MRI Facility, All India Institute of Medical Sciences, New Delhi, Delhi, India, 2Department of Surgical Disciplines, All India Institute of Medical Sciences, New Delhi, Delhi, India, 3Department of Pathology, All India Institute of Medical Sciences, New Delhi, Delhi, India

Apparent diffusion coefficient (ADC) was calculated using diffusion weighted imaging in 72 invasive ductal carcinoma patients at 1.5T with known HER2, ER and PR status. Mean ADC in HER2+, ER+ and PR + were not significantly different compared to HER2-, ER- and PR- patients. Age of ER+ (49±11.3years) patients was statistically significant compared to ER- (43±11.3years). Measured ADC was not significant but showed variation (0.7-1.4x10-3 mm2/s) with the different tumor sub types which might be attributed to intratumor and intertumor heterogeneous nature of breast lesions or other molecular features of breast cancer which is influenced by genomic variation, etc,.

3383.   22 Potential of Perfusion Imaging with IVIM MRI in Breast Cancer -permission withheld
Mami Iima1, Masako Kataoka1, Denis Le Bihan2, Masaki Umehana3, Takuma Imakita3, Masayuki Nakagawa1, Shotaro Kanao1, Kojiro Yano1,4, Thorsten Feiweier5, and Kaori Togashi1
1Diagnostic Imaging and Nuclear Medicine, Kyoto University Graduate School of Medicine, Kyoto, Kyoto, Japan, 2Neurospin, CEA Saclay, Gif-sur-Yvette, Ile-de-France, France, 3Kyoto University Faculty of Medicine, Kyoto, Kyoto, Japan, 4Information Science and Technology, Osaka Institute of Technology, Hirakata, Osaka, Japan, 5Siemens AG, Erlangen, Erlangen, Germany

We performed IVIM MRI in 23 patients with benign and malignant breast lesions. The flowing blood fraction, fivim was significantly (p= 0.01) higher in malignant tumors compared in normal breast, and fivim for malignant tumors showed weak negative correlation with pseudo-diffusion, D*, with a Pearsonfs coefficient (r) of -0.42. There was no significant difference in D* across malignant, benign tumor and normal breast tissue. However, the ADC in malignant tumors was significantly lower than that of benign tumor and normal breast tissue IVIM maps clearly reflected tumor perfusion characteristics, in agreement with Contrast-Enhanced images. These results suggest that images of blood microvasculature can be obtained without contrast agents using IVIM MRI, of high interest for patients with renal failure.

3384.   23 Quantitative DCE- And DW-MRI to Predict the Response of Primary Breast Cancer to Neoadjuvant Therapy
Xia Li1, Lori R. Arlinghaus1, A. Bapsi Chakravarthy1, Richard G. Abramson1, Vandana G. Abramson1, Jaime Farley1, Gregory D. Ayers1, Ingrid A. Mayer1, Mark C. Kelley1, Ingrid M. Meszoely1, Julie Means-Powell1, Ana M. Grau1, Melinda Sanders1, Sandeep R. Bhave2, and Thomas E. Yankeelov1
1Vanderbilt University, Nashville, TN, United States, 2Washington University in St. Louis, St. Louis, MO, United States

DCE-MRI and DW-MRI have been used to predict treatment response in breast cancer. However, in general, quantitative DCE- or DW-MRI parameters are investigated separately and it is not well studied if their combination could improve the diagnostic accuracy to predict the response of primary breast cancer to neoadjuvant therapy. In this study, we attempted to determine if quantitative changes in both DCE-MRI and DW-MRI following a single cycle of chemotherapy can be used to separate responders from non-responders. The results show that the combination of DCE- and DW-MRI improves the ability to predict treatment response than either method alone.

3385.   24 Semi-Automated Method for Improved Reproducibility of Apparent Diffusion Coefficient Measurements in Breast Lesions
Matthew L. Olson1, Habib Rahbar1, Brenda F. Kurland2, Xiaoyu Chai2, Joshua Usoro1, Constance D. Lehman1, and Savannah C. Partridge1
1University of Washington, Seattle, Washington, United States, 2Fred Hutchinson Cancer Research Center, Seattle, WA, United States

On diffusion weighted imaging (DWI), malignant lesions display a lower apparent diffusion coefficient (ADC) than benign lesions, making ADC a potentially useful parameter for discriminating benign and malignant lesions. The low spatial resolution and image quality of DWI can limit interobserver reproducibility of ADC measurements. To address this challenge, we developed a semi-automated method for selection of lesion pixels based on DWI thresholding. Because lesions are typically hyperintense on DWI, a threshold can enable discrimination of lesion pixels from normal parenchyma. We compared inter-observer variability of ADC measurements obtained with this semi-automated approach against the standard manual region-of-interest (ROI) method.


Tuesday, 23 April 2013 (11:00-12:00) Exhibition Hall

  Computer #  
3386.   1 Computed High B-Value DWI for Detection of Prostatic Cancer at 3-Tesla MRI
Yoshiko Ueno1, Satoru Takahashi1, Kazuhiro Kitajima1, Tokunori Kimura2, Ikuo Aoki2, Fumi Kawakami3, Hideaki Miyake4, Yoshiharu Ohno1,5, and Kazuro Sugimura1
1Department of Radiology, Kobe University Graduate School of Medicine, Kobe, Hyogo, Japan, 2Toshiba Medical Systems, Ohtawara, Tochigi, Japan,3Department of Pathology, Kobe University Graduate School of Medicine, Kobe, Hyogo, Japan, 4Department of Urology, Kobe University Graduate School of Medicine, Kobe, Hyogo, Japan, 5Advanced Biomedical Imaging Research Center, Kobe University Graduate School of Medicine, Kobe, Hyogo, Japan

For prostate cancer (PCa) detection, DWI with high b-values over 1000 s/mm2 is recently suggested as useful for providing good contrast between cancerous and background tissue, although several limitations were also suggested. In the last decade, computed DWI (cDWI) is proposed as a new technique that produces any b-value images from DWI acquired with at least two different b-values. The aim of our study was therefore to evaluate the ability of cDWI at b=2000 s/mm2 (cDWI2000) for PCa detection as compared with actually obtained DWI at b=1000 (mDWI1000) and b=2000 s/mm2 (mDWI2000) on a 3T MR system.

3387.   2 Diffusional Kurtosis Imaging of Prostate Cancer: Effect of B-Values and Noise Compensation on Quantitative Parameters, Relative Contrast, and Short-Term Repeatability
Edward M. Lawrence1, Andrew N. Priest1, Tristan Barrett1, Anne Warren2, Ferdia A. Gallagher1, Vincent J. Gnanapragasam3, and Evis Sala1
1Radiology, Addenbrooke's Hospital, Cambridge, Cambridgeshire, United Kingdom, 2Histopathology, Addenbrooke's Hospital, Cambridge, Cambridgeshire, United Kingdom, 3Urology, Addenbrooke's Hospital, Cambridge, Cambridgeshire, United Kingdom

Diffusional kurtosis imaging (DKI) attempts to more accurately quantify water movement by taking into account the possibility of a non-Gaussian distribution. Research into the potential of DKI in the setting of body MRI has been limited and the purpose of this study was to evaluate the effect of b-values and noise compensation on the evaluation of prostate cancer using DKI. Our results showed that DKI is a robust technique that allows for significant differentiation of cancerous regions, as established by whole-mount pathology, regardless of DKI method or tumor location. The highest relative contrast was gained using a high b-value of 1500 s/mm2.

3388.   3 Addition of MR Prostate Volume and Apparent Diffusion Coefficient to D’Amico Classification Improves Prediction of Post-Operative Pathologic Outcomes
Nelly Tan1, Daniel J.A. Margolis1, David Y. Lu2, Htwe K. Khin1, Koroush Beroukhim1, Robert E. Reiter3, and Steven S. Raman1
1Radiology, UCLA, Los Angeles, CA, United States, 2Patholgoy, UCLA, Los Angeles, CA, United States, 3Urology, UCLA, Los Angeles, CA, United States

A retrospective study of 251 men who underwent prostate MRI prior to prostatectomy was performed. The addition of ADC and prostate volume to D'Amico risk classification performed better than D'Amico risk classfication alone in predicting high risk disease. Our results suggest that adding MR prostate volume and ADC to D'Amico classification may improve overall identification of high risk cancer.

3389.   4 Combination of MR Spectroscopic and Diffusion Weighted Imaging of the Prostate for the Prediction of Tumor Aggressiveness
Josephin Otto1, Gregor Thörmer1, Christian Schröder1, Nikita Garnov1, Lars-Christian Horn2, Minh Hoang Do3, Jens-Uwe Stolzenburg3, Michael Moche1, Thomas Kahn1, and Harald Busse1
1Diagnostic and Interventional Radiology Department, Leipzig University Hospital, Leipzig, Saxony, Germany, 2Institute of Pathology, University of Leipzig, Leipzig, Saxony, Germany, 3Department of Urology, Leipzig University Hospital, Leipzig, Saxony, Germany

Active surveillance is regarded as an option to reduce overtreatment in patients with organ-confined low-risk prostate cancer. Transrectal ultrasound-guided biopsy is currently the only method for disease monitoring but has some disadvantages due to its invasive nature and underestimation of tumor dedifferentiation. Multiparametric MRI, on the other hand, can provide quantitative parameters of tissue function that may help to assess tumor aggressiveness. This work evaluates the predictive value of combined DWI and MR spectroscopic parameters to discriminate indolent from aggressive carcinoma.

3390.   5 Zoomed EPI Using Parallel Transmission: Impact on Image Quality of Diffusion-Weighted Imaging of the Prostate at 3T
Andrew B. Rosenkrantz1, Christian Geppert2, Josef Pfeuffer3, David J. Mossa1, and Hersh Chandarana1
1Radiology, NYU Langone Medical Center, New York, New York, United States, 2Siemens Medical Systems, New York, New York, United States, 3Siemens Healthcare, Erlangen, Bavaria, Germany

Six volunteers underwent 3T phased-array coil prostate MRI including DWI performed with both standard EPI and with zoomed EPI incorporating parallel transmission (pTx) and 2D-selective RF pulses. Compared with standard EPI, zoomed EPI showed improved ghosting, wrap artifact, clarity of prostate capsule, and clarity of peri-urethral region on b-1000 images, as well as improved clarity of prostate capsule and overall image quality on the ADC maps. There was a small but significant increase in prostate ADC with zoomed EPI. While zoomed EPI with pTx has potential to improve prostate DWI at 3T, further optimization using smaller FOV remains necessary.

3391.   6 Improved Conspicuity and Delineation of High-Grade Prostate Tumors Using "Restriction Spectrum Imaging": Quantitative Comparison with High B-Value ADC
David Karow1, Nate White1, Jiaoti Huang2, Robert Reiter3, Robert F. Mattrey4, Daniel J.A. Margolis5, Steve Raman5, and Anders M. Dale6
1Radiology, UCSD, La Jolla, CA, United States, 2Pathology, UCLA, Los Angeles, CA, United States, 3Urology, UCLA, Los Angeles, CA, United States, 4Radiology, UCSD, San Diego, CA, United States, 5Radiology, UCLA, Los Angeles, CA, United States, 6Radiology, University of California, San Diego, La Jolla, CA, United States

Restriction spectrum imaging (RSI) is a sensitive DWI technique for probing separable water diffusion compartments in tissues. Here, we evaluate RSI cellularity maps derived from the spherically-restricted water compartment for improved prostate tumor conspicuity and delineation from non-tumor tissue compared with high b-value ADC. Our data support the MRI-derived RSI cellularity maps as potential non-invasive imaging biomarkers for prostate cancer.

3392.   7 Usefulness of Parameters Derived from Intravoxel Incoherent Motion (IVIM) Data – Comparison of Two Methods in Patients with Proven Prostate Carcinoma
Timur H. Kuru1,2, Matthias Roethke1, Heinz-Peter Schlemmer1, Bram Stieltjes1, and Michael Fenchel1
1Department of Radiology, German Cancer Research Center (DKFZ), Heidelberg, BW, Germany, 2Department of Urology, UniversityHospital Heidelberg, Heidelberg, BW, Germany

In recent years, several studies examined the perfusion fraction (f) as well as diffusion coefficients (D) from intravoxel incoherent motion data (IVIM) in patients with prostate cancer (PCa). A multiparametric MR protocol was performed. For quantification of f and D, two distinct curve fitting algorithms were employed. Extracting IVIM parameters in unequivocal tumor regions and normal contralateral parenchyma revealed high variation in perfusion-fractions (f) for both fitting algorithms, probably due to both histological heterogeneity of underlying PCa and potential instability of the fit. In contrast, diffusion coefficient (D) was able to reliably distinguish cancerous from healthy tissue in our cohort.

3393.   8 Diffusion Imaging for Prostate Cancer: A Quantitative Comparison of Echo Planar Imaging and Half Fourier Single Shot Turbo Spin Echo Sequences
Ben Babourina-Brooks1,2, Ian Brereton2, and Gary Cowin2
1School of Cancer Sciences, University of Birmingham, Birmingham, West Midlands, United Kingdom, 2Centre for Advanced Imaging, University of Queensland, Brisbane, Queensland, Australia

DWI has been used to differentiate tumour and healthy tissue in the prostate based on ADC values, however the variation in the value is large enough to have significant overlap of healthy and tumour tissue. EPI is generally used for DWI but has inherent artefacts in imaging due to magnetic susceptibility, chemical shift and phase error. A spin echo based sequence may reduce these errors and produce a more accurate ADC value. In this study we compared HASTE to EPI in tumour detection accuracy. HASTE accuracy results were higher than EPI at the cost of scan time.

3394.   9 Metabolic Signature of Prostate Cancer as Detected with Proton Magnetic Resonance Spectroscopic Imaging and 18F- Fluorodeoxyglucose-Positron Emission Tomography
Amita Shukla-Dave1, Cecilia Wassberg2, Darko Pucar3, Heiko Schoder1, Debra Goldman1, Victor E. Reuter1, James Eastham1, Peter T. Scardino1, Steve M. Larson1, and Hedvig Hricak1
1Memorial Sloan-Kettering Cancer Center, New York, New York, United States, 2Uppsala University Hospital, Uppsala, Uppsala, Sweden, 3Georgia Health Sciences University, Augusta, GA, United States

Although metabolic imaging is frequently performed in cancer patients, the underlying genomic and biochemical mechanisms and the consequent imaging findings remain poorly understood. The purpose of this study was to evaluate citrate metabolism and glucose consumption in prostate cancer (PCa) using 1H-MRSI and 18F-FDG PET. Whole mount step section pathology was used as the standard of reference. Clinical, 1H-MRSI, 18F-FDG PET data were examined in 22 patients. 1H-MRSI was better able to detect index tumors in 21 patients while 18F-FDG PET detected tumor in 3 patients. Thus, we suggest that altered citrate metabolism precedes increased glucose consumption in PCa.

3395.   10 Diffusion-Weighted MRI of the Prostate in Patients with a Significant Family History of Prostate Cancer: Do Histogram Metrics Correlate with Risk?
Maysam Jafar1, Rosalind Eeles2, Sharon L. Giles3, Elizabeth Bancroft2, Elena Castro2, Veronica A. Morgan3, Catherine J. Simpkin3, and Nandita M. deSouza4
1Cancer Research UK and EPSRC Cancer Imaging Centre, Institute of Cancer Research, Sutton, Surrey, United Kingdom, 2Genetics & Epidemiology, Institute of Cancer Research, Sutton, Surrey, United Kingdom, 3Cancer Research UK and EPSRC Cancer Imaging Centre, Royal Marsden NHS Foundation Trust, Sutton, Surrey, United Kingdom, 4Cancer Research UK and EPSRC Cancer Imaging Centre, Institute of Cancer Research & Royal Marsden NHS Foundation Trust, Sutton, Surrey, United Kingdom

Risk of prostate cancer in first-degree relatives is twice that of the general population; 53 single nucleotide polymorphisms (SNPs) have been associated with clinically significant disease in young patients. Diffusion-weighted combined with T2W MRI is sensitive for detecting small prostate tumours. This study prospectively investigates the relationship between histogram parametrics of the apparent diffusion coefficient (centiles, skew, kurtosis) and risk score (derived from 24 SNPs) and showed no correlation in a preliminary analysis. Inclusion of a larger number of SNPs to generate risk score is planned, as the current data fielded a score of <1 in 55% of the cohort.

3396.   11 Diffusion-Weighted MRI of the Prostate at 3-T: Comparison of Endorectal Coil (ERC) MRI and Phased-Array Coil (PAC) MRI – the Impact of SNR on ADC Measurement
Yousef Mazaheri1, Alberto Vargas2, Gregory Nyman2, Amita Shukla-Dave1, Oguz Akin2, and Hedvig Hricak2
1Medical Physics, Memorial Sloan-Kettering Cancer Center, New York, NY, United States, 2Radiology, Memorial Sloan-Kettering Cancer Center, New York, NY, United States

To compare ADC values measured from diffusion-weighted MR (DW-MR) images of the prostate obtained with both endorectal and phased-array coils (ERC+PAC) to those from DW-MRI images obtained with an eight-channel torso phased-array coil (PAC) at 3 Tesla.

3397.   12 Diffusion-Weighted MRI of the Prostate for Tumor Detection in Patients with a Significant Family History of Prostate Cancer: Comparison of Qualitative Vs. Quantitative Analyses
Maysam Jafar1, Veronica A. Morgan2, Sharon L. Giles2, Catherine J. Simpkin2, Rosalind Eeles3, Elizabeth Bancroft3, Elena Castro3, and Nandita M. deSouza4
1Cancer Research UK and EPSRC Cancer Imaging Centre, Institute of Cancer Research, Sutton, Surrey, United Kingdom, 2Cancer Research UK and EPSRC Cancer Imaging Centre, Royal Marsden NHS Foundation Trust, Sutton, Surrey, United Kingdom, 3Genetics & Epidemiology, Institute of Cancer Research, Sutton, Surrey, United Kingdom, 4Cancer Research UK and EPSRC Cancer Imaging Centre, Institute of Cancer Research & Royal Marsden NHS Foundation Trust, Sutton, Surrey, United Kingdom

Diffusion-weighted MRI has increased sensitivity for detecting small prostate cancers when used in conjunction with T2W imaging. This prospective study examines its sensitivity and specificity for detecting tumors in patients with a high-risk (significant family history) of prostate cancer using either qualitative (observer assessed) or quantitative (histogram) analysis. Qualitative analysis had a 77% sensitivity 92% specificity for tumor detection on a per patient basis; ROC curves of 10th and 25th centiles derived from histogram analyses indicated that for a specificity of 90%, sensitivity of these centiles was <25% for detecting tumor in central gland and peripheral zone of the prostate.

3398.   13 Optimization of B-Value Distribution for Biexponential DWI of Normal Prostate
Ivan Jambor1,2, Jukka Järvinen1,3, Hannu J. Aronen1,3, Jani Saunavaara3, Harri Merisaari4, Tommi Kauko5, Ronald Borra1,3, and Marko Pesola1,3
1Department of Diagnostic Radiology, University of Turku, Turku, Finland, 22nd Department of Radiology, Comenius University and St. Elisabeth Oncology Institute, Bratislava, Slovakia, 3Medical Imaging Centre of Southwest Finland, Turku University Hospital, Turku, Finland, 4Turku PET centre, University of Turku, Turku, Finland, 5Department of Biostatistics, University of Turku, Turku, Finland

The optimal b-value distribution for biexponential DWI of normal prostate was determined using using Monte-Carlo simulations and in-vivo measurements. Eight healthy volunteers underwent four repeated 3T prostate DWI scans using both 16 equally distributed b-values and an optimized b-value distribution obtained from the simulations. The b-value distributions were compared in terms of measurement reliability and repeatability using Shrout-Fleiss analysis. The optimal b-value distribution was found to be a clustered distribution with b-values concentrated in the low, mid and high ranges and was shown to improve the estimation quality of biexponential DWI parameters of in-vivo experiments.

3399.   14 Robustness of Normalized ADC Values of Prostate Cancer Against Different Imaging Conditions and Calculation Methods -permission withheld
Harald Busse1, Josephin Otto1, Gregor Thörmer1, Nikita Garnov1, Lars-Christian Horn2, Martin Reiss-Zimmermann1, Thomas Kahn1, and Michael Moche1
1Diagnostic and Interventional Radiology Department, Leipzig University Hospital, Leipzig, Saxony, Germany, 2Institute of Pathology, University of Leipzig, Leipzig, Saxony, Germany

Diffusion-weighted imaging has potential roles in the management of prostate cancer and apparent diffusion coefficients (ADC) could potentially distinguish aggressive from indolent carcinoma. Wider validation, however, will rely on robust quantitative diffusion parameters. This work demonstrates intraindividually that the additional use of an endorectal coil and different b-value data introduce highly significant differences in the absolute ADC values in both tumor and mirror healthy tissue regions. Differences in the ratio of tumor over healthy tissue ADC averages were not significant and make normalized ADC a more robust parameter for the quantification of diffusion abnormalities in the prostate.

3400.   15 Discrimination of Prostate Cancer from Chronic Prostatitis: Comparison Between Biexponential and Monoexponential Models
Wenchao Cai1, Feiyu Li1, Jintang Ye1, Queenie Chan2, Xiaoying Wang1, and Xuexiang Jiang1
1Department of Radiology, Peking University First Hospital, Beijing, Beijing, China, 2Philips Healthcare, Hong Kong, China

Intravoxel incoherent motion (IVIM) MR imaging is a non-invasive method with the ability of separation of ¡°pure¡± molecular diffusion and perfusion effects. Chronic prostatitis mainly contributes low diagnostic specificity of prostate cancer detection in the peripheral zone (PZ). In this study we assess diffusion/perfusion IVIM features in histologically confirmed chronic prostatitis, prostate cancer and normal prostate PZ and compare with conventional DWI using biexponential and monoexponential model respectively. Chronic prostatitis demonstrated significantly higher diffusion characteristics than prostate cancer, while obviously higher perfusion and lower diffusion property than normal PZ detecting via IVIM analysis. IVIM may be of great potential in the better detection of prostate cancer.

3401.   16 Prostate Imaging at 7 Tesla with Fractionated Dipole Antennas: A New Type of Radiative Coil Array Element with Lower SAR Levels.
Alexander Raaijmakers1, Ingmar Voogt1, Dennis W. J. Klomp1, Peter R. Luijten1, and Nico van den Berg1
1Imaging Division, UMC Utrecht, Utrecht, Netherlands

Prostate imaging at 7 Tesla requires advanced coil array elements that are designed according to radiative principles. The single-side adapted dipole antenna (SiSiAD) is one example of such a radiative element. Another example is the fractionated dipole antenna. It is a highly innovative segmented antenna that has demonstrated the same performance as the SiSiAD while not using the heavy and costly ceramic. Four of these elements were combined with four SiSiADs for prostate imaging. Simulations and measurements show that this setup is able to reach the same B1+ efficiency in the prostate with at least 33% lower SAR levels.

3402.   17 Prostate Perfusion Imaging Using Velocity-Selective ASL
Xiufeng Li1 and Gregory J. Metzger1
1Center for Magnetic Resonance Research, University of Minnesota, Minneapolis, MN, United States

Previous prostate ASL perfusion imaging exhibited large inter-subject variability in measured perfusion and arterial transit times (ATT) because of the inability of FAIR to accommodate the complicated, subject dependent architecture of vessels feeding the prostate. FAIR is sensitive to ATT differences between normal and diseased conditions and ATT changes, and also adversely prolongs ATT due to the specific characteristics of vascular geometry around the prostate. VS-ASL labels blood flowing above a specified cutoff velocity, possessing the potential to overcome these limitations. For the first time, VS-ASL imaging method has been applied outside of the brain and in the prostate.

3403.   18 31P MR Spectroscopic Imaging of Patients with Prostate Cancer at 7T
Miriam W. Lagemaat1, Eline K. Vos1, Marnix C. Maas1, Thiele Kobus1, Andreas K. Bitz2,3, Mark J. van Uden1, Stephan Orzada2,3, Arend Heerschap1, and Tom W.J. Scheenen1,2
1Radiology, Radboud University Nijmegen Medical Centre, Nijmegen, Netherlands, 2Erwin L. Hahn Institute for Magnetic Resonance Imaging, Essen, Germany,3Diagnostic and Interventional Radiology, University Hospital Essen, Essen, Germany

The potential of 31P MRSI to detect prostate cancer in vivo at 7T was investigated in 12 patients with or suspected of having prostate cancer. The metabolites ratios PE/γATP, PE/tPLM and Pi/yATP showed significant difference between prostate cancer and normal prostate tissue. The performance of 31P MRSI to detect prostate cancer may improve further by increases in spatial resolution.

3404.   19 Tumor Angiogenesis Correlates with Metastasis in Human Prostate Cancer: An Arterial Spin-Labeling MRI Study
Feiyu Li1, Wenchao Cai1, Jing Wang2, Jue Zhang2,3, Xiaoying Wang1,2, and Xuexiang Jiang1
1Department of Radiology, Peking University First Hospital, Beijing, Beijing, China, 2Academy for Advanced Interdisciplinary Studies, Peking University, Beijing, Beijing, China, 3College of Engineering, Peking University, Beijing, Beijing, China

To explore the correlation between angiogenesis and incidence of metastasis in prostate cancer using Arterial Spin-labeling (ASL) MR Imaging

3405.   20 Prostate Cancer Localization Using Multi-Parametric MRI and a Maximum Likelihood Classification Algorithm
Sharon Clarke1, Bruce Daniel2, Jesse McKenney3, Manojkumar Saranathan2, Brian Andrew Hargreaves2, James Brooks4, Harachan Gill4, Mark Gonzalgo4, Benjamin Chung4, Emine U. Saritas5, Ajit Shankaranarayanan6, and Graham Sommer2
1Diagnostic Radiology, Dalhousie University, Halifax, Nova Scotia, Canada, 2Diagnostic Radiology, Stanford University, Stanford, California, United States,3Anatomic Pathology, Cleveland Clinic, Cleveland, Ohio, United States, 4Urology, Stanford University, Stanford, California, United States, 5Bioengineering, University of California Berkeley, Berkeley, California, United States, 6GE Healthcare, Menlo Park, California, United States

Segmentation of multi-parametric MR images of the prostate gland using a maximum likelihood classification algorithm correlate well with histopathology. These results show promise for identification of clinically relevant prostate cancer for either MR-guided biopsy or focal therapy.

3406.   21 Multiparametric MRI Discriminates Between Benignity and Insignificant and Significant Cancers in MRI-Ultrasound Fusion Targeted Biopsy
Daniel J.A. Margolis1, Edward Chang2, Frederick Dorey3, Jiaoti Huang4, Maria Luz Macairan2, Shyam Natarajan5, Steven Raman1, Geoff Sonn2, and Leonard Marks2
1Radiological Sciences, UCLA David Geffen School of Medicine, Los Angeles, CA, United States, 2Urology, UCLA David Geffen School of Medicine, Los Angeles, CA, United States, 3Department of Pediatrics, USC Keck School of Medicine, Los Angeles, CA, United States, 4Pathology, UCLA David Geffen School of Medicine, Los Angeles, CA, United States, 5Bioengineering, UCLA David Geffen School of Medicine, Los Angeles, CA, United States

The components of multiparametric MRI, including overall suspicion, are evaluated as predictors of the presence of any cancer and significant (Gleason pattern 4) cancer in MRI-ultrasound fusion targeted biopsies. Clinical parameters and standardized scoring of T2 appearance, dynamic contrast enhancement, and overall suspicion on a 1-5 ranked scale after published recommendations, and the quantitative apparent diffusion coefficient (ADC), were compared with the highest Gleason score in biopsy targets. All parameters were predictive of any cancer and, especially, significant cancer, with almost no significant cancer in low (score 1-2) suspicion targets. All except ADC could significantly discriminate Gleason grades in targets.

3407.   22 The Comparison of Arterial Spin Labeling Perfusion MRI and DCE-MRI in Bone Metastasis from Prostate Cancer
Wenchao Cai1, Feiyu Li1, Jing Wang2, Huarui Du2, Jue Zhang2,3, Xiaoying Wang1,3, and Xuexiang Jiang1
1Department of Radiology, Peking University First Hospital, Beijing, Beijing, China, 2Peking University, Department of Biomedical Engineering, Beijing, Beijing, China, 3Academy for Advanced Interdisciplinary Studies, Peking University, Beijing, Beijing, China

Pulsed arterial spin labeling (PASL) MRI is a non-invasive imaging tool capable of quantitatively measuring the microvascular perfusion characteristics of tissue through tagging arterial water to obtain the blood flow (BF) map. Angiogenesis plays a vital role in the metastatic process of prostate cancer, and bone metastasis lesion is hypervascular certificated by dynamic contrast-enhanced (DCE) MRI and histopathologic findings. We applied the PASL technique to detect bone metastasis from prostate cancer and to compare the differences BF values between the metastatic lesions and normal bone in the pelvis. The mean BFs determined by ASL MRI with different TI in the bone metastasis from prostate cancer were significantly higher than those in noncancerous bone regions (P<0.05, Paired T-test) Significant positive correlations between BF value and Ktrans, Kep were observed in all four TI , respectively. ASL is a new non-invasive imaging method with potency in detecting and monitoring therapy efficacy of bone metastasis from prostate cancer.

3408.   23 Probability Maps for Tumour Localisation, Using 3D 1H-MRSI and LCModel Fitting of Model "Benign" and "Tumour" Basis Spectra.
Alan Wright1, Thiele Kobus1, and Arend Heerschap1
1Radboud University Nijmegen Medical Centre, Nijmegen, Gelderland, Netherlands

Probability maps were generated that determine the likelihood of tumour at each spatial location within the prostate based on 3D 1H-MRSI data sets. Each spectrum was fitted with LCModel using a basis set of two model spectra, one for benign and one for tumour tissue. These basis spectra were generated by independent component analysis as the first-two stable components of a data set of 2360 spectra from 42 patients. The probability score separated tumour from benign spectra better than conventional metabolite maps (AUC: 0.782, 0.721 respectively) in this data set and successfully localised significant tumour foci in five new test patients.

3409.   24 Transperineal Prostate Cryoablation Under MR-Guidance
Georgia Tsoumakidou1, Herve Lang2, Julien Garnon1, Elodie Breton3, Eva Rothgang4, and Afshin Gangi1,3
1Interventional Radiology, University Hospital of Strasbourg, Strasbourg, Alsace, France, 2Urology, University Hospital of Strasbourg, Strasbourg, Alsace, France, 3CNRS, ICube Strasbourg University, Strasbourg, Alsace, France, 4Siemens Corporation, Center for Applied Medical Imaging, Strasbourg, Alsace, France

We herein report our initial experience and technical feasibility of transperineal prostate cryoablation under MRI. Percutaneous MR-guided cryoablation was performed in 11 patients with prostatic adenocarcinoma. Real time interactive, multi-slice TrueFISP sequence BEAT_IRTTT was used for the transperineal probe positioning. Real time and high resolution T2 Blade sequences were used for ice ball monitoring. Prostate cryoablation was technically feasible in 10 out of 11 patients.The ice-ball was clearly visualized in all cases as a signal-void area in both real time and high-resolution T2-Blade sequences.


Tuesday, 23 April 2013 (10:00-11:00) Exhibition Hall
Preclinical MR of Cancer: Cells & Animals

  Computer #  
3410.   25 Magnetic Resonance Imaging of Malignant Glioma Using 5-Aminolevulinic Acid in an Animal Model
Seung Hong Choi1
1Radiology, Seoul National University, Seoul, Select, Korea

This study is the first to demonstrate that 5-aminolevulinic acid (ALA) administration increases the intracellular iron concentration of glioblastomas by promoting the synthesis of heme, which is the metabolite of 5-ALA. As intracellular iron can be detected by MRI, we believe that 5-ALA-enhanced MRI will aid in the identification of high-grade foci in gliomas.

3411.   26 in vivo Detection and Characterization of 9L Tumors in Rat Brain by BIRDS
Daniel Coman1, Yuegao Huang1, Henk M. De Feyter1, Douglas L. Rothman1,2, and Fahmeed Hyder1,2
1Diagnostic Radiology, Yale University, New Haven, CT, United States, 2Biomedical Engineering, Yale University, New Haven, CT, United States

Development of MRI contrast agents has provided outstanding ability to identify diseased tissue, while MRS has unlocked new windows into molecular bases of diseases. But no magnetic resonance technology exists that can extract quantitative molecular information from a contrasted region. Beyond the gray scale distinction of an affected tissue targeted by an MRI contrast agent we cannot assess the state of the affected tissue because MR signals are compromised by the presence of contrast agents. In this present work we show that TmDOTP5- can be used as dual contrast agent for tumor detection and molecular MR reporting of cellular status.

3412.   27 Sodium-Diffusion MRI of Emerging Drug Resistance in Rat Glioma Model
Victor D. Schepkin1, Thomas Morgan2, Shannon Gower-Winter2, Petr L. Gor'kov1, William W. Brey1, and Cathy W. Levenson2
1National High Magnetic Field Lab/FSU, Tallahassee, Florida, United States, 2College of Medicine, FSU, Tallahassee, Florida, United States

Tumor progression, especially after therapeutic intervention, increases tumor resistance to therapies; consequently, it requires a much higher concentration of a chemotherapeutic drug to achieve the same response, otherwise success may not be feasible. In gliomas sodium concentration and diffusion are usually higher than normal brian and its variations demonstrate an attractive correlation with glioma drug resistance. The hypothesis is that the increased tumor resistance is determined by a more efficient energy metabolism which can be detected by the corresponding decrease of glioma sodium concentration or even diffusion; thus, MRI can noninvasively reveal emerging tumor drug resistance before therapy.

3413.   28 Microbeam Radiation Therapy Effects on White Matter Assessed by Fiber Tractography
Yohan van de Looij1,2, Audrey Bouchet3,4, Benoit Pouyatos3, Luc Renaud5, Elke Bräuer-Krisch4, Géraldine Le Duc4, Jean A. Laissue6, and Raphaël Serduc3
1Division of Child Growth & Development, University of Geneva, Geneva, Switzerland, 2Laboratory for Functional and Metabolic Imaging, Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland, 3Grenoble Institut des Neurosciences UMR836, Université Joseph Fourier, Grenoble, France, 4European Synchrotron Radiation Facility, Grenoble, France, 5Centre de Recherche Cerveau et Cognition, Université de Toulouse, Toulouse, France, 6Institute of Pathology, University of Bern, Bern, Switzerland

Microbeam Radiation Therapy (MRT) is a preclinical form of radiosurgery dedicated to brain tumor treatment. It uses micrometer-wide synchrotron-generated X-ray beams on the basis of spatial beam fractionation. Rat brain external capsule was damaged using MRT at different radiation deposition doses and assessed by DTI and fiber tractography. This study shows the excellent ability of DTI to classify the degree of injury of diverse lesions by DTI derived parameters and 3D representation of the WM fibers in the injury. The severity of the damage matches very well with DTI and FT results.

3414.   29 Characterization of an Orthotopic Mouse Model Developed from Human Glioblastoma Spheres
Feriel Tiar1, Teodora-Adriana Perles-Barbacaru1, Michelle El-atifi1, Didier Wion1, Laurent Pelletier1, Hana Lahrech1, and Francois Berger1
1INSERM U 836, Grenoble Institute of Neurosciences, La Tronche, France

A new orthotopic mouse model derived from human glioblastoma spheres was recently developed. Tumor growth kinetics and response to temozolomide treatment was assessed by MRI. Similar to clinically encountered glioblastomas, this model develops over several months, has an infiltrating growth pattern, mimics their cellular heterogeneity and presents a temozolomide failure. It will therefore be useful for the preclinical evaluation of new treatment strategies.

3415.   30 Tumor pH and Vascularity in Human Prostate Cancer Models
Ellen Ackerstaff1, Natalia Kruchevsky1, Radka Stoyanova2, Sean D. Carlin1, Nerissa Viola-Villegas1, Kuntalkumar Sevak1, Jason S. Lewis1, and Jason A. Koutcher1
1Memorial Sloan Kettering Cancer Center, New York, NY, United States, 2Miller School of Medicine University of Miami, Miami, FL, United States

Tumor hypoxia and pH have been related to tumor aggressiveness, treatment response, and outcome. Here, we evaluated tumoral pH, metabolism, and vascularity in human prostate cancer models using 1H-decoupled 31P MR spectroscopy and dynamic contrast-enhanced MR imaging (DCE-MRI). Tumoral, extracellular pH (pHe) was measured using 3-aminopropylphosphonate (3-APP), while spatial heterogeneity of tumor hypoxia was evaluated from DCE-MRI data using a novel pattern recognition approach. In tumors without extensive necrosis, pHe appears to be only slightly acidic and tied to the extent of tumoral hypoxia, as determined from vascularity.

3416.   31 A Method for Identifying Tumor Sub-Regions with Similar Enhancement Characteristics Based on Volumetric High Resolution DCE-MRI
Ergys Subashi1,2, Everett J. Moding3, James R. MacFall4,5, David G. Kirsch3, Yi Qi2,5, and G. Allan Johnson2,5
1Medical Physics Graduate Program, Duke University Medical Center, Durham, NC, United States, 2Center for In-Vivo Microscopy, Duke University Medical Center, Durham, NC, United States, 3Department of Pharmacology and Cancer Biology, Duke University Medical Center, Durham, NC, United States,4Department of Biomedical Engineering, Duke University Medical Center, Durham, NC, United States, 5Department of Radiology, Duke University Medical Center, Durham, NC, United States

The histogram or mean value of the pharmacokinetic parameters derived from dynamic contrast-enhanced MRI is usually obtained from a manual ROI or from the entire tumor volume. These metrics include tumor regions in which the interpretation of the kinetic parameters is unclear (such as in necrotic areas). In five separate tumor cell lines, we have found that the histogram of the time-to-peak (TTP) parameter can be used to identify tumor sub-volumes with similar enhancement properties. Preliminary results show that the magnitude of response to therapy may be heterogeneous across these sub-regions.

3417.   32 Comparison of T1, T2 and T2* Contrast Agents in the Perfusion Assessment of a Glioma Rat Model
Rocío Pérez-Carro1 and Pilar López-Larrubia1
1Instituto de Investigaciones Biomédicas, CSIC-UAM, Madrid, Madrid, Spain

Cerebral perfusion assessment by DSC-MRI has become a frequently used tool for evaluation of numerous neuropathologies. The technique is based on the intravenous injection of contrast agent and subsequent bolus tracking using a fast susceptibility-weighted imaging sequence. In this work we to assess the brain perfusion in a glioma rat model by using this technique and four contrast media with different relaxation and plasma half-life properties: a Gd-based T1 agent, a Dy-based T2, and two iron-oxide nanoparticles to enhance T2*-contrast. We show that that Dy chelates provide the best signal to noise ratio and the higher values for hemodynamic parameters.

3418.   33 Detection of the Effect of Nanoparticle Preconditioning in a Mouse Model of Prostate Cancer by MRI
Isabelle Iltis1, Jeunghwan Choi2, Manda Vollmers1, Mithun Shenoi2, John Bischof2, and Gregory J. Metzger1
1Radiology, Center for Magnetic Resonance Research - University of Minnesota, Minneapolis, Minnesota, United States, 2Department of Mechanical Engineering, Bioheat and Mass Transfer Laboratory - University of Minnesota, Minneapolis, Minnesota, United States

Pre-treatment of tumors using TNF- lower case Greek alpha based nanoparticles is a promising approach to improve the outcome of “conventional” (e.g., radiation therapy, chemotherapy, thermal therapies) treatment. The intravenous injection of nanoparticles leads to a set of physiological events specifically in the tumor (such as decreased local perfusion and increased interstitial space) known as preconditioning. To be used in clinical routine, methods for measuring pre-conditioning in vivo are highly desirable. In this work, we show in a mouse model of prostate cancer that DCE-MRI, as used routinely in patients, is an excellent candidate to assess the effects of preconditioning in vivo.

3419.   34 Cytotoxic Effects of Magnetic Field Gradients on Iron Oxide Labeled Cancer Cells -permission withheld
Sudath Hapuarachchige1,2, Yoshinori Kato1,3, and Dmitri Artemov1,3
1Division of Cancer Imaging Research, Russell H. Morgan Department of Radiology and Radiological Sc., The Johns Hopkins University School of Medicine, Baltimore, MD, United States, 2In vivo Cellular Molecular Imaging Program, The Johns Hopkins University School of Medicine, Baltimore, MD, United States,3Department of Oncology, Sidney Kimmel Comprehensive Cancer Center, The Johns Hopkins University School of Medicine, Baltimore, MD, United States

We have demonstrated that oscillating gradients of magnetic field induce significant damage to cells labeled with magnetic nanoparticles, such as superparamagnetic iron oxide (SPIO), in the presence of saturating static magnetic field. Specific labeling of cells with iron oxide can be achieved either by internalization of nanoparticles using standard cell transfection reagents and techniques or by modifying the cell surface with targeted magnetic nanoparticles. This novel treatment procedure, called GIFT (gradient-induced Fe therapy), can be implemented on a standard MRI system that makes the technology applicable for clinical use.

3420.   35 Monitoring Temporally Selective LDH-A Gene Deletion in Prostate Cancer Using Hyperpolarized Frequency Specific 13C-MRI
Subramaniam Sukumar1, Robert A. Bok2, Daniel B. Vigneron3, Pankaj Seth4, and John Kurhanewicz1
1Radiology and Biomedical Imaging, UCSF, San Francisco, California, United States, 2Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, California, United States, 3Radiology and Biomedical imaging, UCSF, San Francisco, California, United States, 4Medicine, Beth Israel Deaconess Med Center, Boston, MA, United States

Lactate Dehydrogenase expression and activity is up-regulated in various malignancies, including prostate cancer. In a recently developed transgenic mouse model, in which the LDH-A gene is deleted selectively in a temporal fashion, hyperpolarized 13C frequency specific MRI method was used to monitor early changes in LDH-A expression within prostate tumor tissue.

3421.   36 in vivo 2D L-COSY Detects Decreased PC in Gliomas After Treatment with MN58b, a Choline Kinase Inhibitor
Gaurav Verma1, Manoj Kumar1, Sona Saksena2, Ranjit Ittyerah2, Anatoliy V. Popov2, Jenny Li3, M. Albert Thomas3, Edward James Delikatny2, and Harish Poptani1
1Department of Radiology and Radiation Oncology, University of Pennsylvania, Philadelphia, PA, United States, 2Department of Radiology, University of Pennsylvania, Philadelphia, PA, United States, 3Department of Radiological Sciences, University of California Los Angeles, Los Angeles, CA, United States

The treatment response of rat gliomas to a choline-kinase inhibitor, MN58b, was quantified using a 2D localized correlated spectroscopy (L-COSY) sequence in a 9.4T horizontal bore scanner. In vivo 2D spectra from six normal brains, five untreated tumors and three treated tumors, showed uniquely resolvable peaks of several metabolites including phosphocholine (PC) and glycerophosphocholine (GPC). The PC/GPC ratio was found to be elevated in tumor compared to normal rat brain (1.04 vs. 0.88), and then found to decrease to an average of 0.86 following treatment with MN58b.

3422.   37 Early Detection of Response to Radiotherapy in Brain Metastases Using Dynamic Contrast-Enhanced Magnetic Resonance Imaging
Chen-Hao Wu1,2, Chuan-Han Chen1, Yi-Ying Wu1, Jyh-Wen Chai3, Clayton Chi-Cheng Chen3, Chung-Ming Chen2, and Wen-Yih Isaac Tseng2,4
1Department of Radiology, Taichung Veterans General Hospital, Taichung, Taiwan, 2Institute of Biomedical Engineering, National Taiwan University, Taipei, Taiwan, 3Taichung Veterans General Hospital, Taichung, Taiwan, 4Center for Optoelectronic Biomedicine, National Taiwan University College of Medicine, Taipei, Taiwan

Early assessment of metastatic brain tumor response to radiotherapy is vital for treatment optimization for the individual cancer patient. The purpose of this study was to assess the performance of DCE, a novel MRI protocol for apoptosis, as a tool for the early detection of response of brain metastases to radiation therapy.

3423.   38 Induction of Apoptosis by High Levels of Oscillatory Shear Strain: Proof of Concept in a Human Colon Cancer Metastasis Cell Line. -permission withheld
Philippe Garteiser1, Mouniya Mebarki1, Sabrina Doblas1, Simon Auguste Lambert1, Valérie Vilgrain2, Bernard E. Van Beers2, Valerie Paradis3, and Ralph Sinkus1
1U773-CRB3, INSERM, Universite Sorbonne Paris-Cite, Paris, 75018, France, 2Service de Radiologie, AP-HP Hopital Beaujon, Clichy, 92110, France, 3Service d'Anatomo-Pathologie, AP-HP Hopital Beaujon, Clichy, 92110, France

Cells are able to sense their mechanical environment and to respond to it via appropriate cellular responses mediated via mechanotransduction. In particular, many cell types can regulate their levels of apoptosis, or programmed cell death, depending on which mechanical stimuli they receive. In the present communication, we show that calibrated levels of oscillatory shear strain, as measured by MR elastography, is sufficient to induce cellular death via apoptosis in the human colon cancer metastasis cell line, DHDK12.

3424.   39 Combination of Perfusion and Diffusion-Weighted MRI for Functional Evaluation of Therapeutic Response of Lung Cancer
Yeun-Chung Chang1, Ang Yuan2, Chia-Hsien Cheng3, Yi Fang Chen4, Yi-Chien Lu1, Kua-Hung Cho5, and Jyh-Horng Chen6
1Department of Medical Imaging, National Taiwan University Hospital and National Taiwan University College of Medicine, Taipei, Taiwan, Taiwan, 2Department of Internal Medicine, National Taiwan University Hospital and National Taiwan University College of Medicine, Taipei, Taiwan, Taiwan, 3Department of oncology, National Taiwan University, Taipei, Taiwan, Taiwan, 4Institute of Clinical Dentistry, National Taiwan University, Taipei, Taiwan, Taiwan, 5Instrumentation Resource Center, National Yang-Ming University, Taipei, Taiwan, Taiwan, 6National Taiwan University, National Taiwan University, Taipei, Taiwan, Taiwan

Combination of both DCE-MRI and DW-MRI provides more comprehensive understanding of change of internal tumor composition. Many preclinical studies have indicated that the addition of various types of antiangiogenic or antivascular therapy to single-dose or fractionated radiotherapy can synergistically improve the response of human and murine tumors to treatment.

3425.   40 Multimodality Imaging Assessments of Response to Metformin Therapy for Breast Cancer in Nude Mice
Yi Mao1, Rui xia1, Lei Wang1, yuqing wang1, and Fabao Gao1
1Department of Radiology, West China Hospital, Sichuan University, chengdu, sichuan, China

Metformin: A Therapeutic Opportunity in Breast Cancer? Metformin in Cancer Therapy: A New Perspective for an Old Antidiabetic Drug? But there is few creditable studies have assessed the in vivo effects of metformin in cancer. We assessed the usefulness of diffusion-weighted imaging (DWI) and bioluminescence imaging (BLI) in evaluating tumor response to metformin.

3426.   41 Is Higher Lactate Generation Rate an Indicator of Tumor Metastatic Risk?-A Pilot Study Using Hyperpolarized 13C-NMR
He N. Xu1, Stephen J. Kadlececk1, Harrilla Profka1, Ben Pullinger1, Jerry D. Glickson1, Rahim Rizi1, and Lin Z. Li1
1University of Pennsylvania, Philadelphia, PA, United States

Increased glycolysis resulting in higher lactate production (the Warburg effect) has been demonstrated in tumor tissues in numerous studies including some that employed hyperpolarized 13C-NMR. High levels of hyperpolarized lactate were correlated with high tumor grades. In this study we aim to investigate if the difference in levels of hyperpolarized lactate reflects differences in tumor growth rate or tumor metastatic risk. We examined two breast tumor mouse models, the less metastatic but faster growing (MCF-7) and the more metastatic but slower growing (MDA-MB-231) tumors and quantitatively compared their metabolism using the hyperpolarized 13C-1-pyruvate NMR technique.

3427.   42 Evaluating the Metabolic Profile of Prostate Cancer Cells Using an MR Compatible Bio-Reactor
Mithun Kailavasan1, Steven Reynolds1, Adriana Bucur1, Samira Kazan2, Tooba Alizadeh2, Gillian M. Tozer2, Ishtiaq Rehman3, and Martyn Paley1
1Academic Radiology, University of Sheffield, Sheffield, Yorkshire, United Kingdom, 2Oncology, University of Sheffield, Sheffield, Yorkshire, United Kingdom,3Human Metabolism, University of Sheffield, Sheffield, Yorkshire, United Kingdom

Prostate cancer cells with varying metastatic potential (LNCaP and LNCaP-LN3) were cultured in a customized cell bioreactor system, adapted for a 9.4T Nuclear Magnetic Resonance (NMR) probe, which allowed extended cell survival. Several metabolite levels were continuously measured over time, including lactate, fatty acid, alanine, choline, glutamine and creatine, both with and without the addition of a pyruvate dehydrogenase kinase inhibitor, dichloroacetate (DCA). Zymography was used to assess LDH isoenzymes. Rat p22 sarcoma cells were used as a control. Zymography assays (n=4), showed an absence of the LDH-B subunit in both LNCaP-LN3 and rat p22 cell lines. LNCaP-LN3 and rat p22 cells had a 18600µmol/108 cells (p<0.001) and 6600µmol/108 cells (p=0.039) median difference, respectively, in lactate levels compared to LNCaP. Median Cho/Cr ratios at 1hr decreased following DCA treatment in LNCaP and LNCAP-LN3 (p<0.001). Creatine levels increased over time in all 3 cell lines by showing efficiency of the bioreactor design.

3428.   43 Assessment of the Serine Synthesis Pathway During Breast Cancer Progression Using 13C-MRS
Dania Daye1,2, Suzanne Wehrli3, Chris Sterner2,4, Tien-Chi Pan2,4, Mitchell D. Schnall5, and Lewis A. Chodosh2,4
1Department of Bioengineering, University of Pennsylvania, Philadelphia, PA, United States, 2Abramson Family Cancer Research Institute, University of Pennsylvania, Philadelphia, PA, United States, 3NMR Core Facility, Children's Hospital of Philadelphia, Philadelphia, PA, United States, 4Department of Cancer Biology, University of Pennsylvania, Philadelphia, PA, United States, 5Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania, United States

Among women with breast cancer, tumor recurrence represents the principal cause of mortality. Nevertheless, little is known about the molecular mechanisms underlying how breast cancer recurs. In particular, while dysregulated metabolism has long been recognized as a key feature of cancer development, the metabolic changes accompanying cancer recurrence are largely unexplored. Increased serine biosynthesis has been recently found to be important in tumorigenesis. Yet, no association has been established between this metabolic pathway and cancer progression. In this study, we investigate the differences in serine metabolism between primary and recurrent mammary tumors and assess their role as potential prognostic markers.

3429.   44 Validation of Hyperpolarized 13C Lactate as a Prostate Cancer Biomarker Using a Human Prostate Tissue Slice Culture Bioreactor
Kayvan R. Keshari1, Renuka Sriram1, Mark Van Criekinge1, David M. Wilson1, Zhen J. Wang1, Daniel B. Vigneron1, Donna M. Peehl2, and John Kurhanewicz1
1Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, CA, United States, 2Stanford University, Stanford, CA, United States

The treatment of prostate cancer has been impeded by both the lack of clinically relevant disease models and biomarkers that track tumor progression. Hyperpolarized 13C MR has been developed to address these concerns, and safety of 13C pyruvate was confirmed in a recent clinical trial. The present study provides the first validation of HP lactate as a prostate cancer biomarker in human tissues, critical for the interpretation of in vivo studies. A prostate tissue slice culture model that recapitulates the metabolic profile of prostate cancer in vivo was developed, applied to a perfused cell (bioreactor) platform.

3430.   45 NMR Metabolomics of Drug Response to Antineoplastic Polyherbal Formulations Studied in Human Hepatocellular Carcinoma Cells
G. Sharma1, Rama Jayasundar1, T. Velpandian2, R. Singh3, S. S. Chauhan3, V. Kapoor4, and S. N. Das4
1NMR, All India Institute of Medical Sciences, New Delhi, India, 2Ocular Pharmacology & Pharmacy, All India Institute of Medical Sciences, New Delhi, India,3Biochemistry, All India Institute of Medical Sciences, New Delhi, India, 4Biotechnology, All India Institute of Medical Sciences, New Delhi, India

The study has used NMR metabolomics to profile drug response of Hep-G2 tumor cells to treatment by chemotherapeutic drug paclitaxel and four polyherbal formulations, all of which had antineoplastic activity assessed by apoptosis detection assay. Proton spectrum of untreated cells showed prominent resonances between 3.5-3.8ppm. These peaks showed drastic reduction in response to treatment by paclitaxel and formulations. In addition, there were also other spectral changes. PCA analysis of the spectral data of drug induced metabolic changes showed a clear difference between the untreated and treated cells with the spectral response to paclitaxel and one of the formulation being similar.

3431.   46 Altered Choline Phospholipid Metabolism in a Panel of Pancreatic Cancer Cell Lines
Tariq Shah1, Marie-France Penet1, Yelena Mironchik1, Flonné Wildes1, Anirban Maitra2, and Zaver M. Bhujwalla1
1Division of Cancer Imaging Research, Johns Hopkins University, Baltimore, MD, United States, 2Pathology, Johns Hopkins University, Baltimore, MD, United States

Pancreatic cancer is an aggressive disease that develops in a relatively symptom-free manner and is usually advanced at the time of diagnosis. There is an urgent need of biomarkers for early diagnosis with enough sensitivity and specificity to help diagnose pancreatic cancer. In this study, we have used 1H MRS to characterize the metabolic profile of a panel of pancreatic cancer cells. Immortalized pancreatic cells were used for comparison. While elevated choline containing compounds were present in all adenocarcinomas relative to immortalized pancreatic cells, differences were also observed within the adenocarcinoma cell lines. The altered choline phospholipid metabolism could be used for non-invasive diagnosis and staging of pancreatic cancer using 1H MRS. The aberrant choline metabolism may also provide novel targets in the treatment of pancreatic cancer.

3432.   47 Monitoring PKM2 Status in Glioblastoma Using Hyperpolarized 13C MRS
Myriam Marianne Chaumeil1, Joydeep Mukherjee2, Humsa Venkatesh1, Russell O. Pieper2, and Sabrina M. Ronen1
1Radiology, University of California, San Francisco, San Francisco, CA, United States, 2Neurological Surgery, University of California, San Francisco, San Francisco, CA, United States

The M2 isoform of pyruvate kinase (PKM2) induces a reprogramming of energetic metabolism in cancer cells, leading to tumor growth and metastasis. Because PKM2 modulation is being investigated as a therapeutic approach, we questioned whether hyperpolarized (HP) 13C MRS of pyruvate could serve as a method to probe the PKM2 status. This study shows that knocking down PKM2 expression in glioblastoma cells leads to a significant decrease in HP lactate formation. HP13C MRS of pyruvate could thus prove useful for evaluation of new PKM2-targeted therapies.

3433.   48 Choline Kinase Alpha Has Ethanolamine Kinase Activity and Its Choline Kinase Activity Is Modulated by Ethanolamine in Breast Cancer Cells
Tariq Shah1, Jannie P. Wijnen1, Flonné Wildes1, Balaji Krishnamachary1, Kristine Glunde1, and Zaver M. Bhujwalla1
1Division of Cancer Imaging Research, Johns Hopkins University, Baltimore, MD, United States

An increase of total choline is a hallmark of cancer, largely driven by increased phosphocholine and phosphoethanolamine. While significant effort has been focused on the increased phosphocholine observed in cancer cells and tumors, increased phosphoethanolamine has been underexplored. Increased phosphocholine, but not phosphoethanolamine, is observed in cells in culture because culture medium contains free choline but not ethanolamine. Here we have demonstrated that breast cancer cells in culture have the ability to form phosphoethanolamine if ethanolamine is provided in the medium, that choline kinase alpha is capable of ethanolamine kinase activity, and its choline kinase activity is influenced by ethanolamine concentrations.


Tuesday, 23 April 2013 (11:00-12:00) Exhibition Hall

  Computer #  
3434.   25 Comparison of R2* Measurements Values and Reproducibility in Liver Metastases and Normal Liver
Nina Tunariu1,2, David John Collins1, James A. d'Arcy3, Veronica A. Morgan1, Sharon L. Giles1, Catherine J. Simpkin1, Timothy A. Yap4, and Nandita M. De Souza5
1CR-UK and EPSRC Cancer Imaging Centre, Institute of Cancer Research & The Royal Marsden Hospital, Sutton, London, United Kingdom, 2Drug Development Unit, Institute of Cancer Research & The Royal Marsden Hospital, Sutton, London, United Kingdom, 3CR-UK and EPSRC Cancer Imaging Centre, The Institute of Cancer Research, Sutton, London, United Kingdom, 4Section of Medicine, Institute of Cancer Research & The Royal Marsden Hospital, Sutton, London, United Kingdom, 5CR-UK and EPSRC Cancer Imaging Centre, Institute of Cancer Research, Sutton, London, United Kingdom

Intrinsic susceptibility weighted (ISW) MRI and derived R2*measurements have been described as potential tool for tumour hypoxia assessment in prostate and breast cancer. The aim of this study was to measure R2* in normal liver and in liver metastases, compare these measurements and establish their reproducibility. This small study showed that R2* measurements in liver metastases are significantly different from normal liver R2* values and can be obtained with reasonable reproducibility. Improvement in data acquisition and data post processing are essential. Liver R2* values also need validation with regard to their utility as a surrogate biomarker for hypoxia.

3435.   26 Discrimination of Dysplastic Nodules from Well-Differentiated (Grade 1) Hepatocellular Carcinoma on MR Imaging: Evaluation with LIRADS and OPTN Criteria
Surachate Siripongsakun1, Eugene K. Choi1, Stephanie Lin1, Steven S. Raman1, and David S.K. Lu1
1Radiology, David Geffen School of Medicine at UCLA, Los Angeles, California, United States

Purpose: To assess the diagnostic performance of MRI characteristics, LIRADS and OPTN criteria in distinguishing well-differentiated (grade 1) hepatocellular carcinoma (HCC-gr1) from dysplastic nodules (DN). Results: Significant differences in T1 and T2 signal, and the presence of contrast wash-in/out and a capsule between both DN and HCC-gr1 (p<0.001 - 0.008). T2 hyperintense signal, intratumoral fat and a tumor capsule were identified in 4(17.4%), 3(13%) and 4(17.4%) of DNs, respectively. Two DNs (8.7%) were assigned a LIRAD5 (definite HCC) and one HCC was an assigned a LIRADS3 (intermediate probability for HCC). In comparison, 5 (21.7%) and 10 HCC (21.7% were assigned an OPTN5 (HCC) and OPTN4 (intermediate suspicion for HCC), respectively. Conclusion: MR allows for excellent differentiation between DN and very well-differentiated HCC (grade I), although overlap in MR characteristics do exist. LIRADS performed better than OPTN criteria to distinguish between DN and gr1 HCC.

3436.   27 Which Is Better for Detection of Hepatocellular Carcinoma (HCC) and Vessel Thrombus? Comparison of Superparamagnetic Iron Oxide (SPIO) - Enhanced T2*- Weighted Imaging (T2*WI) and 3D Balanced Turbo Field-Echo (B-TFE) with a T2 Preparation Pulse (T2 Prep)
Masayuki Kanamoto1,2, Kazuki Terashima3, Tosiaki Miyati2, Kei Katahira1, Ryoji Ida1, Daisaku Suga4, and Nobukazu Fuwa3
1Department of Radiation Tecnology, Hyogo Ion Beam Medical Center, Tatsuno, Hyogo, Japan, 2Division of Health Sciences, Graduate School of Medical Science, Kanazawa University, Kanazawa, Ishikawa, Japan, 3Department of Radiology, Hyogo Ion Beam Medical Center, Tatsuno, Hyogo, Japan, 4Hyogo Ion Beam Medical Support, Tatsuno, Hyogo, Japan

The purpose of the study was to compare SPIO-enhanced 3D B-TFE with T2 prep and 2D T2*WI in order to detect HCC and vessel thrombus in greater detail. Twenty-three patients with a portal thrombus or venous thrombus were administered SPIO. The contrast between HCC, liver, vessel, and thrombus was calculated. The contrast between HCC and liver in T2*WI was significantly higher than in B-TFE (p < 0.05). B-TFE exhibited higher contrast between thrombus and vessels than T2*WI (p < 0.01). It may also be helpful for simultaneous detection of HCC and vessel thrombus using B-TFE.

3437.   28 Performance of Gd-EOB-DTPA MRI Criteria for Diagnosis of Pathologically Proven HCC: A Comparison with AASLD and Barcelona Criteria.
Anokh Pahwa1, Katrina Beckett2, Stephanie Channual2, Nelly Tan2, David Lu2, and Steven Raman2
1Olive View-UCLA Medical Center, Sylmar, CA, United States, 2UCLA, Los Angeles, CA, United States

Hepatobiliary specific MR contrast is becoming more prevalent, and understanding its applicability with existing imaging criteria is essential for the noninvasive evaluation of the cirrhotic liver. The purpose was to determine the applicability of Gd-EOB-DTPA, an extracellular contrast agent, with and without hepatobiliary phase imaging in conjunction with established AASLD and Barcelona Criteria for imaging-based diagnosis of hepatocellular carcinoma (HCC). Hepatobiliary phase imaging when using Gd-EOB-DTPA increased sensitivity for the diagnosis of HCC when compared to using established criteria alone, with a small decrease in specificity, which supports a role for hepatobiliary specific contrast agents to improve diagnosis of HCC.

3438.   29 Measurement Reproducibility of ADC for Liver Metastases Using Multi B Value Diffusion Weighted Imaging: Preliminary Results.
Richard Kinh Gian Do1, David H. Gultekin2, Seth S. Katz1, Michael J. Sohn1, Charles G. Nyman1, Emily C. Zabor3, Chaya M. Moskowitz3, and Diane L. Reidy4
1Radiology, Memorial Sloan-Kettering Cancer Center, New York, NY, United States, 2Medical Physics, Memorial Sloan-Kettering Cancer Center, New York, NY, United States, 3Epidemiology and Biostatistics, Memorial Sloan-Kettering Cancer Center, New York, NY, United States, 4Medicine, Memorial Sloan-Kettering Cancer Center, New York, NY, United States

Limited data exist on the reproducibility of ADC of liver metastases using multiple b value DWI. 14 patients with neuroendocrine liver metastases were prospectively recruited. We calculated ADC and ADChigh using 5 b value from 0-500 s/mm2 or 3 b values > 100 s/mm2, respectively. Intra-class correlations (ICC) for ADC of all 44 metastases was 0.845 (CI 0.733,0.912) and for ADChigh was 0.380 (CI: 0.093,0.608). For right hepatic metastases, ADC ICC = 0.895 (CI 0.778,0.952), ADChigh ICC = 0.766 (CI 0.535,0.890). From Bland-Altman analyses, change > 0.56x10-3mm2/s in ADC of metastases (>0.46 x10-3mm2/s for right lobe metastases) would be significant.

3439.   30 Diagnostic Performance of Delayed Hepatobiliary Imaging Post Gadoxetic Acid Combined with DWI Vs. Dynamic Contrast-Enhanced Imaging for HCC Detection: Pilot Data.
Cecilia Besa1, Nancy A. Cooper1, Sara Lewis2, Amita Kamath1, Sasan Roayaie3, Marcelo Facciuto4, Isabel I. Fiel5, and Bachir Taouli6
1Radiology, Mount Sinai Medical School, New York, NY, United States, 2Radiology, Mount Sinai Medical School, New York, NY, United States Minor Outlying Islands, 3Surgery, Mount Sinai Medical School, New York, NY, United States, 4Surgery, Mount Sinia Medical School, New York, NY, United States, 5Pathology, Mount Sinai Medical School, New York, NY, United States, 6Mount Sinai School of Medicine, New York, NY, United States

The diagnostic performance of the combination of hepatobiliary phase (HBP) imaging post gadoxetic acid (Gd-EOB-DTPA) and DWI compared to dynamic contrast-enhanced (CE) imaging using ASSLD 2011 criteria were assessed for detection of HCC > 1 cm. Pilot data demonstrate better sensitivity and lower specificity when using HBP + DWI compared to AASLD 2011 criteria (wash-in/wash-out) for HCC detection. Data analysis of more cases is pending

3440.   31 Gadoxetic Acid-Enhanced MRI of Liver: Can 5 Min-Delayed Hepatocyte-Phase Imaging with High Flip Angle (30°) Replace 20 Min-Delayed Hepatocyte-Phase Imaging with Low Flip Angle (10°)?
Eun-Suk Cho1 and Jeong-Sik Yu1
1Radiology, Yonsei University College of Medicine, Gangnam Severance Hospital, Seoul, Korea

In gadoxetic acid-enhanced MRI of liver, 5 min-delayed hepatocyte phase imaging (HPI) using 30° flip angle (FA) has higher or similar lesion-to-liver CNR and detection rate for focal hepatic lesions, compared to 20 min HPI using 10° FA. This indicates that 5 min-delayed HPI using high FA (30°) could replace 20 min delayed HPI using standard low FA (10°) with 15 min time-saving, because the former provides higher or similar diagnostic performance compared to the latter.

3441.   32 31P MRSI as an Early Indicator of Response to Radiation Treatment in Liver Cancer
Tony Clevenger1,2, Anshuman Panda1,3, Scott Jones1,2, Kumar Sandrasegaran2, Higinia Cardenes4, and Ulrike Dydak1,2
1School of Health Sciences, Purdue University, West Lafayette, Indiana, United States, 2Department of Radiology and Imaging Sciences, Indiana University School of Medicine, Indianapolis, Indiana, United States, 3Department of Radiology, Mayo Clinic Arizona, Scottsdale, Arizona, United States, 4Department of Radiation Oncology, Indiana University School of Medicine, Indianapolis, Indiana, United States

Phosphorous-31 (31P) MRSI has been shown to distinguish well between healthy and malignant liver tissue. The current RECIST criteria to monitor response of hepatocellular cancer (HCC) to radiation therapy often take up to 6 months to show results, and can be ambiguous or erroneous. Results are presented of our pilot study showing that 31P MRSI in HCC patients can predict treatment response within one month of radiation therapy. These results indicate that 31P MRSI has potential as an early indicator of response to radiation therapy.

3442.   33 The Potential of High Resolution MR Imaging at 3 and 7 Tesla for Treatment Guidance of Early Glottic Carcinoma.
Johanna J. Bluemink1, Marielle E.P. Philippens1, Wouter Koning2, Chris Terhaard1, Frank A. Pameijer2, Peter R. Luijten2, and Cornelis A.T. van den Berg1
1Radiotherapy, UMC Utrecht, Utrecht, Netherlands, 2Radiology, UMC Utrecht, Utrecht, Netherlands

Small glottic tumors are generally visualized by laryngoscopy and no imaging is used because thus far most imaging modalities have insufficient resolution to detect them. Here we demonstrate that with sequence and setup optimization both 3T and 7T MRI can have sufficient resolution to capture small structures around the larynx. The images obtained in 2 patients yielded new information to the head and neck physician concerning the preferred choice of treatment.

3443.   34 Diffusion Weighted Imaging in Head-And-Neck Cancer: Comparison Between Echo Planar and Turbo Spin Echo Sequences
Tim Schakel1, Gert van Yperen2, Johan van den Brink2, Frank A. Pameijer3, Chris Terhaard1, Hans Hoogduin3, and Marielle E.P. Philippens1
1Radiotherapy, UMC Utrecht, Utrecht, Netherlands, 2Philips Healthcare, Best, Netherlands, 3Radiology, UMC Utrecht, Utrecht, Netherlands

Current DW-EPI images are, due to the geometric distortions, unsuitable for delineation purposes for radiotherapy treatment planning in head-and-neck cancer patients. The presented alternative, DW-SPLICE, can produce distortion free images at the cost of longer acquisition times and increased blurring.

3444.   35 Adaptive Model for Direct Estimation of Hemodynamic Parameters in MR Perfusion Studies: Comparison and Evaluation Using CT Perfusion and Singular Value Decomposition Technique
Hassan Bagher-Ebadian1,2, Rajan Jain1, Jayant Narang1, and Hamid Soltanian-Zadeh1,3
1Radiology, Henry Ford Hospital, Detroit, Michigan, United States, 2Physics, Oakland University, Rochester, Michigan, United States, 3CIPCE-Department of ECE, University of Tehran, Tehran, Tehran, Iran

This study investigates feasibility of using a model-trained Adaptive Model to estimate Mean-Transit-Time (MTT) and relative-Cerebral-Blood-Flow (rCBF) in Dynamic-Susceptibility (DSC)-MR perfusion studies. A residue function with an exponential kernel was used to model the T2*-weighted-images with bolus passage. The ANN was trained and validated using a set of central moments and K-Folding-Cross-Validation (KFCV) technique. DSC-MR perfusion and CT-perfusion studies of four patents were analyzed using the ANN and Singular-Value-Decomposition technique. Results imply that the ANN produces accurate and stable hemodynamic maps compared to the SVD technique which can be used as a fast and accurate estimator in DSC perfusion studies.

3445.   36 No Volumetric and Metabolic Differences in the Brain Between Severely Fatigued and Non-Fatigued Disease-Free Cancer Survivors
H. Prinsen1, H. W.M. van Laarhoven1,2, G. Bleijenberg3, M. J. Zwarts4, M. van der Graaf5,6, M. Rijpkema7, and Arend Heerschap5
1Medical Oncology, Radboud University Nijmegen Medical Centre, Nijmegen, Gelderland, Netherlands, 2Medical Oncology, Academic Medical Centre, University of Amsterdam, Amsterdam, Noord-Holland, Netherlands, 3Expert Centre for Chronic Fatigue, Radboud University Nijmegen Medical Centre, Nijmegen, Gelderland, Netherlands, 4Epilepsy Centre Kempenhaeghe, Heeze, Noord-Brabant, Netherlands, 5Radiology, Radboud University Nijmegen Medical Centre, Nijmegen, Gelderland, Netherlands, 6Clinical Physics Laboratory, Radboud University Nijmegen Medical Centre, Nijmegen, Gelderland, Netherlands, 7Nuclear Medicine, Radboud University Nijmegen Medical Centre, Nijmegen, Gelderland, Netherlands

Until now, little is known about (neuro)physiological factors determining postcancer fatigue, which is a frequently occurring problem, impairing quality of life. For non-cancer patients with chronic fatigue syndrome, certain characteristics of brain morphology and metabolism were already identified. We investigated whether these volumetric and metabolic traits are a reflection of fatigue in general and thus also be of importance for postcancer fatigue. However, the studied volumetric and metabolic parameters are not related to postcancer fatigue. This may suggest that, although postcancer fatigue and chronic fatigue syndrome show strong resemblances as a clinical syndrome, the underlying physiology is different.

3446.   37 Rapid ex vivo Imaging of PAIII Prostate to Bone Tumor with SWIFT-MRI
Ihor Luhach1, Djaudat Idiyatullin2, Conor Lynch1, Curtis Andrew Corum3, Gary V. Martinez1, Michael Garwood3, and Robert J. Gillies4
1H. Lee Moffitt Cancer Center and Research Institute, Tampa, FL, United States, 2Center for Magnetic Resonance Research, University of Minnesota, Minneapolis, MN, United States, 3University of Minnesota, Minneapolis, MN, United States, 4H. Lee Moffitt Cancer Center, Tampa, FL, United States

In U.S. almost 30,000 men die from prostate cancer every year. Up to 90% of them develop bone metastasis. Early detection of metastases can be beneficial for treatment and long term survival.Sweep Imaging with Fourier Transform or SWIFT is a new MRI method capable of detecting signals with a broad range of T2 times including extremely short ones that are present in bone. In this work control and PAIII tumor bearing mice tibia were imaged with SWIFT, traditional CT, gradient echo and spin echo. SWIFT was capable to detect tumor and tumor related osteogenesis in the same image.

3447.   38 Relationships Between Diffusion Weighted Signal Intensity, ADC and Water/fat Content of Malignant Bone Marrow
Ashik Amlani1, Subhadip Ghosh-Ray1, Katherine van Ree1, Andreas Makris2, Shirley D'Sa2, Peter Ostler2, Nicola Anyamene2, and Anwar R. Padhani1
1Paul Strickland Scanner Centre, Mount Vernon Cancer Centre, London, Middlesex, United Kingdom, 2Mount Vernon Cancer Centre, London, United Kingdom

There are stepwise increases in tissue-normalised SI, ADC values and water:fat ratio when sequentially comparing YBM to RBM and malignant bone marrow disease. The polynomial relationships between both DW-SI and water:fat ratio with ADC values are independent of tumour type allowing an opportunity to set a generally applicable upper ADC limit (threshold) for untreated/relapsed disease.

3448.   39 Whole Body Diffusion-Weighted Imaging (WB-DWI) to Assess Treatment Response in Multiple Myeloma
Sharon L. Giles1, Christina Messiou1, David John Collins1,2, Veronica A. Morgan1, Faith E. Davies3,4, Gareth Morgan3,4, and Nandita M. deSouza1,2
1MRI Department, Royal Marsden Hospital, Sutton, Surrey, United Kingdom, 2Clinical Magnetic Resonance, Institute of Cancer Research, Sutton, Surrey, United Kingdom, 3Haemato-oncology Department, Royal Marsden Hospital, Sutton, Surrey, United Kingdom, 4Molecular Pathology, Institute of Cancer Research, Sutton, Surrey, United Kingdom

WB-DWI offers an alternative to serum paraproteins and bone trephine for response assessment in myeloma. This prospective study compared image appearances, mean ADCs and histogram characteristics of volumetric marrow segmentions in myeloma patients pre and post treatment, using laboratory tests as the gold standard to define response. There were significant differences in ADC change between responders and non-responders (14% increase vs 6% decrease, p=0.008), with a strong correlation between change in ADC and laboratory markers of response (r = -0.77, p<0.001). WB-DWI is a useful biomarker of response, but relative roles for qualitative and quantitative analysis need to be determined.

3449.   40 Comparison of SUV Between Simultaneous PET/MRI and PET/CT: A Single Injection Study in Patients with Cancer
Shanaugh McDermott1, Ronald Borra2, Michael Blake1, Dushyant V. Sahani1, Grae Arabasz2, Shirley Hsu2, Lawrence T. White2, Mary Ohara2, Jacob M. Hooker2, Ciprian Catana3, Bruce R. Rosen2, and Alexander R. Guimaraes2
1Radioloy, Massachusetts General Hospital; Division of Abdominal Imaging and Interventional Radiology, Boston, MA, United States, 2Radiology; Massachusetts General Hospital, Martinos Center for Biomedical Imaging, Charlestown, MA, United States, 3Radiology; Massachusetts General Hospital, Massachusetts General Hospital, Charlestown, MA, United States

This study is a comparison of PET/MRI to PET/CT in a single injection study performed on the same day. Lesions that were FDG avid were compared on a lesion specific basis and categorized by anatomic region. Linear regression was performed in order to quantify the correlation.

3450.   41 Early Predictive Power of Magnetic Resonance Imaging Parameters During Neoadjuvant Chemotherapy in Uterine Cervical Cancer
Yuki Himoto1, Koji Fujimoto1, Aki Kido2, Shigeaki Umeoka2, Kayo Kiguchi2, Fuki Shitano2, Tsukasa Baba3, Ikuo Konishi3, and Kaori Togashi2
1Department of Diagnostic Imaging and Nuclear Medicine, Kyoto University, Kyoto, Kyoto, Japan, 2Department of Diagnostic Imaging and Nuclear Medicine, Kyoto University Hospital, Kyoto, Kyoto, Japan, 3Department of Gynecology and Obsterics, Kyoto University Hospital, Kyoto, Kyoto, Japan

To evaluate utility of quantitative measurements in MRI for the early prediction of neoadjuvant chemotherapy (NAC) effectiveness in cervical cancer, 13 patients with stage 1b-2b squamous cell carcinoma were assessed. They were performed NAC and radical hysterectomy. Tumor volume, diffusion, and perfusion parameters were correlated to the eventual tumor volume reduction rate after NAC was completed. Significant correlation was found for the early tumor volume regression rate (R=0.84, p<0.001), pretreatment Ve (R=0.64, p<0.05,) and its early change (R=|0.63, p<0.05).

3451.   42 K-Means Clustering of DCE-MRI Pharmacokinetic Parameters for Prediction of Chemotherapeutic Response of Bladder Cancer
Huyen Thanh Nguyen1, Guang Jia1, Zarine K. Shah2, Kamal S. Pohar3, Amir Mortazavi4, Debra L. Zynger5, Xiangyu Yang1, and Michael V. Knopp1
1Wright Center of Innovation in Biomedical Imaging, Department of Radiology, The Ohio State University, Columbus, OH, United States, 2Department of Radiology, The Ohio State University, Columbus, OH, United States, 3Department of Urology, The Ohio State University, Columbus, OH, United States,4Department of Internal Medicine, The Ohio State University, Columbus, OH, United States, 5Department of Pathology, The Ohio State University, Columbus, OH, United States

Purpose: to evaluate the capability of k-means clustering of DCE-MRI pharmacokinetic parameters in predicting chemotherapeutic response of bladder cancer at mid-cycle of chemotherapy. Methods: K-means clustering of voxel-based pharmacokinetic parameters was performed to determine the three cluster centroids. For each tumor, volume fraction of each cluster was calculated; and their changes from baseline to mid-cycle were determined and correlated with the tumor’s chemotherapeutic response. Results: The changes in the volume fraction of the three clusters from baseline to mid-cycle MRIs trended in the opposite directions and were significantly different between responders and non-responders (P<0.01). Conclusion: K-means clustering of DCE-MRI pharmacokinetic parameters shows robustness in revealing the complex change of microcirculation to enable prediction of chemotherapeutic response of bladder cancer at mid-cycle MRI.

3452.   43 MR Imaging Features of Gastrointestinal Stromal Tumor (GIST) of the Gastrointestinal (GI) Tract -permission withheld
Mi Hye Yu1, Jeong Min Lee2, Jee Hyun Baek2, Joon Koo Han1, and Byung-Ihn Choi1
1Radiology, Seoul National University Hospital, Seoul, Seoul, Korea, 2Radiology, Seoul National University, Seoul, Seoul, Korea

We investigated the imaging features of GIST of the GI tract on dynamic contrast-enhanced MRI. The most common MR imaging feature of GIST of the GI tract was well-defined, lobulated, exophytic growing tumor showing obvious and gradually progressive enhancement, and heterogeneity with intratumoral hemorrhage or necrotic/cystic change. The enhancement pattern, enhancement grade and heterogeneity of GIST were variable according to the size of the tumor. Small GIST appeared as round tumor with obvious, early strong or peripheral to central enhancement, meanwhile large GIST appeared as lobulated exophytic growing heterogeneous tumor with mild, gradually progressive enhancement.

3453.   44 Quantitative DCE-MRI as a Predictor of Acute Leukemia Response to Therapy
Mohan L. Jayatilake1, Aneela Afzal1, Xin Li1, Yiyi Chen2, William J. Woodward1, Tibor J. Kovacsovics3, William H. Fleming3,4, and Wei Huang1
1Advanced Imaging Research Center, Oregon Health & Science University, Portland, OR, United States, 2Biostatistics, Oregon Health & Science University, Portland, OR, United States, 3Center for Hematologic Malignancies, Knight Cancer Institute, Oregon Health & Science University, Portland, OR, United States,4Oregon Stem Cell Center, Oregon Health & Science University, Portland, OR, United States

Nine newly diagnosed acute myelogenous leukemia (AML) patients underwent DCE-MRI of vertebral body and iliac crest before standard chemotherapy. The pre-therapy bone marrow mean kep was found to be a good predictor of complete remission following therapy. DCE-MRI may be a useful noninvasive imaging method for non-solid tumor cancer studies.

3454.   45 Adult Lymphoma: Comparison of Whole-Body Diffusion Weighted Sequence MR Imaging with an Enhanced PET/CT Reference for Initial Staging -permission withheld
Sikandar Mohammed Shaikh1,2

Purpose: To compare the diagnostic value of whole-body anatomic magnetic resonance (MR) staging of adolescent lymphoma to an enhanced positron emission tomographic (PET)/computed tomographic (CT) as reference standard. Materials and Methods Thirty-one subjects (age range, 27.3–48.0 years; 18 male, 13 female) with histologically proved lymphoma were prospectively evaluated. Pretreatment staging was performed with whole-body DWI MR imaging, fluorine 18 fluorodeoxyglucose PET/CT, and contrast agent–enhanced CT. Eleven nodal and 11 extranodal sites per patient were assessed on MR imaging by radiologist in consensus, with a nodal short-axis threshold of >1cm and predefined extranodal positivity criteria. The same sites were independantly evaluated by a nuclear medicine physician on PET/CT images. Disease positivity was defined as a maximum standardized uptake value >2.5 or nodal size >1 cm and further evaluated by ê value . Results: There was very good agreement between DWI MR imaging and the enhanced PET/CT reference standard for nodal and extranodal staging (ê = 0.96 and 0.86, respectively) which improved following elimination of perceptual errors (ê = 0.97 and 0.91, respectively). The sensitivity and specificity of DWI MR imaging (following removal of perceptual error) were 98% and 99%, respectively, for nodal disease and 91% and 99%, respectively, for extranodal disease. Conclusion: Whole-body DWI MR imaging of adult lymphoma can accurately depict nodal and extranodal disease and may provide an alternative nonionizing imaging method for anatomic disease assessment at initial staging.

3455.   46 High-Resolution in vivo Imaging of Inguinal Lymph Nodes Using 7 Tesla MRI: A Feasibility Study.
Martin T. Freitag1, Mathies Breithaupt2, Ann-Kathrin Homagk2, Moritz Berger2, and Bram Stieltjes1
1Quantitative Imaging-based Disease Characterization, German Cancer Research Center (DKFZ), Heidelberg, Baden-Wuerttemberg, Germany, 2Department of Medical Physics in Radiology, German Cancer Research Center (DKFZ), Heidelberg, Baden-Wuerttemberg, Germany

Clinical imaging of inguinal lymph nodes plays a vital role in cancer staging. However, conventional MRI approaches lacks sufficient sensitivity to detect micro-metastasis in lymph nodes. Here, we present a feasible in vivo high resolution approach to visualize inguinal lymph nodes at 7 Tesla. Using a T1 sequence and a loop-coil we could stably acquire data at a 0.38x0.38x0.38 mm³ isotropic resolution. Normal lymph node architecture could be well visualized in all healthy subjects. In the melanoma patient, the absence of a fat hilus and the nodal infiltration with pathological vessels, both signs of malignant transformation, could be recognized readily.

3456.   47 Breast Tissue Expanders with Magnetic Ports: In Vitro Testing and Clinical Experience at 1.5-Tesla
Nanda Deepa Thimmappa1, Frank G. Shellock2, Cristen Giangarra3, Christina Y. Ahn4, Martin R. Prince1, and Joshua L. Levine5
1Radiology, Weill Cornell Medical College, New York, NY, United States, 2Radiology, University of Southern California, Los Angeles, CA, United States,3University College of Washington University, Saint Louis, MO, United States, 4NYC Breast Reconstruction Center, New York, NY, United States, 5Plastic Surgery, The Center for the Advancement of Breast Reconstruction at NYEE, New York, NY, United States

MR safety of tissue expanders with magnetic ports implanted following mastectomy for breast cancer is controversial yet these patients often require MRI/MRA examinations while the expander is present. Based on in vitro and clinical testing in 16 patients, we found these implants create substantial artifact but no migration, local heating or other damage.