Traditional Poster Session - Cancer
  Breast 1462-1499
  Prostate 1500-1517
  Cancer Models - Novel Contrast 1518-1524
  Cancer Models - DCE 1525-1532
  Cancer Models - Therapy Response 1533-1543
  Cancer - Cells 1544-1546
  Cancer - Others 1547-1551
  Cancer Models - Metabolism & Spectroscopy 1552-1555
     

Breast
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Wednesday 9 May 2012
Exhibition Hall  10:00 - 12:00

1462.   High resolution breast DWI to evaluate the tumor-stromal boundary in patients receiving neoadjuvant chemotherapy
Rebekah L McLaughlin1, David C Newitt2, Catherine Park3, Dorota Wisner2, Lisa J Wilmes2, Evelyn Proctor2, and Nola Hylton1,2
1The UC Berkeley - UCSF Graduate Program in Bioengineering, UC Berkeley & UCSF, San Francisco, CA, United States, 2Department of Radiology and Biomedical Imaging, UCSF, San Francisco, CA, United States, 3Department of Radiation Oncology, UCSF Helen Diller Comprehensive Cancer Center, San Francisco, CA, United States

 
Using a high resolution DWI sequence for the breast, we investigated the changes in diffusion measurements relative to distance from the tumor boundary in patients receiving neoadjuvant treatment. In this study, we found that tumors and surrounding tissue had variable ADC patterns before and during neoadjuvant chemotherapy, suggesting that water mobility properties vary among tumors. Our early results suggest that a decrease in the change of tumor to stroma mean ADC values may identify tumors that will respond.

 
1463.   Effect of Neoadjuvant Chemotherapy on the Fibroglandular Tissue Volume and Breast Density in the Contralateral Normal Breast: Evaluate at 3T MRI
Jeon-Hor Chen1,2, Wei-Fan Pan2, Chih-Chen Kuo2, Julian Kao1, Li-Kuang Chen1, Jocelyn Lu1, Shadfar Bahri1, Rita S Mehta3, Daniel H-E Chang1, Orhan Nalcioglu1, and Min-Ying Lydia Su1
1Center for Functional Onco-Imaging, Department of Radiological Science, University of California, Irvine, California, United States, 2Department of Radiology, China Medical University Hospital, Taichung, Taiwan, 3Department of Medicine, University of California Irvine, Orange, California, United States

 
The results from our previous MRI monitoring study had shown that the reduction of breast density in patients receiving neoadjuvant chemotherapy (NAC) was majorly related to Doxorubicin and Cyclophosphamide (AC). The effect of taxane on the change of breast tissue is still not clear. 49 women receiving a new NAC protocol starting with 12 weeks of taxane with optional AC were studied for their 3D MR density change. The results show that NAC using Abraxane and Carboplatin also had similar effect on the reduction of FV and PD as did AC. The effect is age-related and duration-related. Since quantitative measures of FV and PD can be obtained on MRI, the reduction of these two parameters after NAC may potentially be used an imaging biomarker to correlate with future cancer risk occurring in the contralateral normal breast.

 
1464.   Towards Optimization of DCE-MRI Analysis for Early Prediction of the Response of Breast Cancer Patients to Neoadjuvant Chemotherapy
Xia Li1, Lori R. Arlinghaus1, A. Bapsi chakravarthy1, E. Brian Welch1, Jaime Farley1, Ingrid A. Mayer1, Vandana G. Abramson1, Richard G. Abramson1, Mark C. Kelley1, Ingrid M. Meszoely1, Julie A. Means-Powell1, Ana M. Grau1, Sandeep Bhave1, and Thomas E. Yankeelov1
1Vanderbilt University Institute of Imaging Science, Nashville, Tennessee, United States

 
Tumor response to neoadjuvant chemotherapy is currently monitored by frank changes in tumor size, which often do not correlate with pathologic findings at surgery. DCE-MRI offers information related to tumor perfusion and permeability, vascular volume, and extravascular extracellular volume fraction. In this study, we attempted to determine the optimal analysis method for assessing if changes in these parameters after one cycle of therapy could separate pathologic complete responders from non-responders. The results show that tumor perfusion and permeability and vascular volume yield significant differences between responders and non-responders, but that changes in tumor volume do not.

 
1465.   Voxel-based Analysis of early DCE-MRI Changes May Predict the Response to Neoadjuvant Chemotherapy in Breast Cancer Patients
Xia Li1, Lori R. Arlinghaus1, A. Bapsi chakravarthy1, E. Brian Welch1, Jaime Farley1, Ingrid A. Mayer1, Vandana G. Abramson1, Mark C. Kelley1, Ingrid M. Meszoely1, Julie A. Means-Powell1, Ana M. Grau1, Sandeep Bhave1, and Thomas E. Yankeelov1
1Vanderbilt University Institute of Imaging Science, Nashville, Tennessee, United States

 
To monitor tumor response to neoadjuvant chemotherapy, investigators have begun to employ the quantitative physiological parameters available from dynamic contrast enhanced MRI (DCE-MRI). However, most studies track the changes in average parameter values obtained from the whole tumor region of interest, thereby discarding all spatial information on tumor heterogeneity. In this study, we applied a novel registration algorithm to longitudinal DCE-MRI data and performed a voxel-by-voxel analysis. The results indicate that voxel-based analysis, after longitudinal registration, may improve the ability of DCE-MRI to separate pathologic complete responders from non-responders after one cycle of therapy when using the fast exchange regime model.

 
1466.   Multivariate Analysis of DCE-MRI for Early Prediction of Breast Tumor Response Using Machine Learning
Xia Li1, Subramani Mani1, Lori R. Arlinghaus1, A. Bapsi chakravarthy1, E. Brian Welch1, and Thomas E. Yankeelov1
1Vanderbilt University Institute of Imaging Science, Nashville, Tennessee, United States

 
Dynamic contrast enhanced MRI (DCE-MRI) can offer information related to tumor perfusion and permeability, vascular volume, extravascular extracellular volume fraction, and the intracellular water lifetime of a water molecule. There have been many efforts employing DCE-MRI as a surrogate biomarker for predicting the response of breast tumors to neoadjuvant chemotherapy. However, most studies perform univariate analysis on these parameters. In this study, we perform multivariate analysis using machine learning methods. The preliminary results demonstrate the feasibility of using DCE-MRI data and machine learning for predicting the response of breast tumors to a single cycle of neoadjuvant chemotherapy.

 
1467.   High-resolution DWI for Characterizing Breast Tumor Response to Treatment
Lisa J Wilmes1, Rebekah L McLaughlin1, Sumedha Sinha1, David C Newitt1, Lisa Singer1, Evelyn Proctor1, Dorota Wisner1, Emine U Saritas2, Ajit Shankaranarayanan3, Suchandrima Banerjee3, Bonnie N Joe1, and Nola M Hylton1
1University of California San Francisco, San Francisco, CA, United States, 2University of California Berkeley, Berkeley, CA, United States, 3Applied Science Laboratory, GE Healthcare, Menlo Park, CA, United States

 
A high-resolution reduced field of view diffusion-weighted imaging sequence (HR-DWI) was optimized for breast imaging and evaluated against a standard (STD-DWI) sequence in patients with invasive breast cancer undergoing neoadjuvant treatment. Mean tumor apparent diffusion coefficients (ADCs) were not significantly different between sequences. However, the mean lower percentile ADCs were lower for HR-DWI, and this difference was significant at the early treatment time point. Of the ADC metrics evaluated, the pre-treatment 15th percentile HR-ADC was found to correlate most strongly with tumor volume change at the end of treatment. These results suggest HR-DWI may have value in characterizing treatment responses.

 
1468.   Highly-Accelerated Golden-Angle Radial Acquisition with Joint Compressed Sensing and Parallel Imaging Reconstruction for Breast DCE-MRI
Sungheon Kim1, Li Feng1, Linda Moy1, Melanie Moccaldi1, Kai T. Block1, Daniel K. Sodickson1, and Ricardo Otazo1
1Center for Biomedical Imaging, Radiology, NYU School of Medicine, New York, NY, United States

 
Both high temporal and high spatial resolutions of DCE-MRI are required for screening patients with high risk of the breast cancer using pharmacokinetic model analyses. The objective of our study was to investigate the feasibility of using a novel image reconstruction method that combines compressed sensing and parallel imaging for radial trajectories (k-t RASPS) for DCE-MRI study of the breast cancer. Unilateral breast MRI was performed with six patients using golden-angle radial VIBE pulse sequence. Our results demonstrate that high temporal resolutions images (up to 1.2 s/frame) can be reconstructed without noticeable temporal blurring.

 
1469.   Evaluation of 3D Extended Echo Train T2-weighted Imaging for the Characterization of Breast Lesions
Catherine J Moran1, Brian A Hargreaves1, Manojkumar Saranathan1, and Bruce L Daniel1
1Radiology, Stanford University, Stanford, CA, United States

 
T2-weighted images contribute to differential diagnosis in breast MRI. In this work we evaluate a clinically available high-resolution 3D extended echo train T2-weighted acquisition in comparison to a conventional Fast Spin Echo acquisition in 27 breast MRI patients. Depiction of lesion morphology, lesion signal intensity, and the discernment of benign from malignant lesions are assessed for each sequence. Potential diagnostic implications of the utilization of 3D T2-weighted imaging in the breast are also noted.

 
1470.   Pharmacokinetic parameter of DCE-MRI and US-localized optical imaging in Breast cancer: According to Pathologic Biomarker
Min Jung Kim1,2, Ji Soo Choi1, Hon J Yu3, Jeon-Hor Chen3, Min-Ying Su3, Eun-Kyung Kim1, and Hee Jung Moon1
1Radiology, Yonsei University College of Medicine, Seoul, Korea, 2John Tu and Thomas Yuen Center for Functional Oncoimaging, UC Irvine, Irvine, CA, United States, 3John Tu and Thomas Yuen Center for Functional Oncoimaging, UC Irvine

 

1471.   Correlation of Endogenous Hormonal Levels, Fibroglandular Tissue Volume and Breast Density Measured Using 3D MRI
Jeon-Hor Chen1,2, Christine McLaren3, Wen-Pin Chen3, Siwa Chan4, Dah-Cherng Yeh5, Orhan Nalcioglu1, and Min-Ying Lydia Su1
1Center for Functional Onco-Imaging, Department of Radiological Science, University of California, Irvine, California, United States, 2Department of Radiology, China Medical University Hospital, Taichung, Taiwan, 3Department of Epidemiology, University of California, Irvine, California, United States, 4Department of Radiology, Taichung Veterans General Hospital, Taichung, Taiwan, 5Department of Surgery, Taichung Veterans General Hospital, Taichung, Taiwan

 
The correlation between levels of endogenous estrogen and progesterone and measures of fibroglandular tissue volume and percent breast density analyzed on 3D MRI was studied. Twenty-four healthy premenopausal Asian women were recruited. Each woman received 4 weekly breast MRIs during their MC. Blood sample was also collected at the same day. It was found that there was significant correlation of FV and PD with endogenous estradiol, and FV with progesterone in the third week after the starting of menstruation. Our study did not find strong evidence of a weekly lag effect of endogenous hormone on the measured FV and PD. The results from this study raised the possibility that the association between sex hormone and breast cancer may be mediated, in part, by increasing breast density.

 
1472.   Correcting Breast DWI distortion with Reversed phase encoding direction
Zhan Xu1, Leah Henze Bancroft1, Andrew L Alexander2,3, and Frederick Kelcz4
1Department of BioMedical Engineering, University of Wisconsin Madison, Madison, WI, United States, 2Department of Medical Physics and Psychiatry, University of Wisconsin Madison, Madison, WI, United States, 3Waisman Laboratory for Brain Imaging, University of Wisconsin Madison, Madison, WI, United States, 4Department of Radiology, University of Wisconsin Madison, Madison, WI, United States

 
Our work aims at restoring undistorted DWI for breast imaging which is suffering from imperfect fat suppression and low SNR. We acquire two identical DWIs with reversed Phase Encoding Direction then apply correction in a manner of averaging magnetic field inhomogeneity. Corrected DWIs were compared with identical T2W NoFatSuppression images. Our methods well reconstruct the undistorted DWI,both location and signal intensity of lesion and breast are well maintained.

 
1473.   Association of the Amount of Fibroglandular Tissue on MRI and background parenchymal enhancement on DCE-MRI with Breast Cancer Risk
Alana R. Amarosa1, Sungheon Kim1, Amy Melsaether1, Jason McKellop1, Melanie Moccaldi1, and Linda Moy1
1Radiology, NYU School of Medicine, New York, New York, United States

 
The purpose of this study is to investigate whether the amount of fibroglandular tissue on MRI and background parenchymal enhancement are associated with breast cancer risk. This retrospective study included 36 BRCA mutation carriers and 40 controls who underwent MRI-guided biopsy for an enhancing lesion. When comparing signal percent enhancement for pre- and post-menopausal BRCA carriers, we found a significant difference (p=0.04). Also, menopausal BRCA carriers had higher early enhancement rate than pre-menopausal BRCA carriers. No such difference was found between pre- and post-menopausal control groups. These findings substantiate our hypothesis that breast cancer risk is associated with breast density.

 
1474.   Feasibility of contrast-enhanced and high resolution MR-imaging in patients with suspicious breast lesions at 7 Tesla.
Bertine L. Stehouwer1, Dennis W.J. Klomp1, Peter R. Luijten1, Karel A.F. Houwert2, Paul J. van Diest3, Willem P.Th.M. Mali1, Maurice A.A.J. van den Bosch1, and Wouter B. Veldhuis1
1Radiology, University Medical Center, Utrecht, Utrecht, Netherlands, 2Radiology, Zuwe Hofpoort Hospital, Woerden, Utrecht, Netherlands, 3Pathology, University Medical Center, Utrecht, Utrecht, Netherlands

 
Eighteen patients with 21 biopsied breast lesions were imaged at 7T. The protocol included a dynamic series consisting of 7 consecutive 3D T1-weighted turbo field echo sequences and ultra-high resolution imaging with a 0.45x0.57x0.45mm3 acquisition matrix. All 21 malignant lesions were scored according the BI-RADS-MRI criteria by two radiologists, independently, using the dynamic series. Subsequent ultra-high resolution imaging increased reader confidence in n=13 and=9 for the separate radiologists and changed interpretation in n=3 and n=5 cases for the radiologists. Overall, we showed the feasibility of clinical 7T CE breast MRI, and its amenability to BI-RADS-MRI conform analysis.

 
1475.   Population Variability of Susceptibility-Induced B0 Field in Bilateral Breast MRI
Seung-Kyun Lee1, and Ileana Hancu1
1GE Global Research, Niskayuna, NY, United States

 
Susceptibility-induced B0 field in bilateral breast was calculated in thirteen healthy volunteers based on segmented anatomical images at 3 T. For each volunteer, nine axial B0 maps were fitted with spherical harmonics up to the third order, and population variability was investigated. Common features in the susceptibility-induced B0 gradient were identified and the effectiveness of higher order shim was evaluated.

 
1476.   Dynamic analysis of breast lesions: Can we use the wash-in phase instead of the wash-out phase?
Ritse M Mann1, Roel DM Mus1, Christian Geppert2, Cindy PM Frentz1, Nico Karssemeijer1, Henkjan Huisman1, and Bram Platel1,3
1Radiology, Radboud University Nijmegen Medical Centre, Nijmegen, Gld, Netherlands, 2Oncology, Siemens Healthcare, Erlangen, Germany, 3Fraunhofer MEVIS, Bremen, Germany

 
Initial maximum slope of enhancement as derived from ultrafast TWIST images acquired during contrast inflow provides a strong discriminator between benign and malignant disease that outperforms classic 3-timepoint analysis. By using a fixed grid of relative enhancement versus time curve types can be defined that can be easily implemented in current radiological practice.

 
1477.   Clinical evaluation of 3D diffusion-weighted breast imaging with dual echo steady state (DESS)
Kristin Granlund1,2, Jafi Lipson1, Jennifer Kao1, Debra Ikeda1, Brian Hargreaves1, and Bruce Daniel1
1Radiology, Stanford University, Stanford, California, United States, 2Electrical Engineering, Stanford University, Stanford, California, United States

 
The DESS sequence has been proposed to acquire 3D high-resolution, low-distortion diffusion-weighted images in reasonable scan times. In this abstract, we have three radiologists evaluate images acquired with DCE, DWI, and DESS sequences. Radiologists evaluated the visibility of lesions, the image sharpness, the lesion margin, rim signal, and internal setpa. We found that DESS highlighted more lesions than DWI, had better image quality, which made morphology easier to assess.

 
1478.   Feasibility of extracting quantitative arterial input functions from descending aorta in breast DCE MRI studies
Dennis Lai Hong Cheong1,2, Bingwen Zheng1, Bo Zhang1,3, Soo Chin Lee4,5, and Thian Chor Ng1,6
1Clinical Imaging Research Center, A*STAR & National University of Singapore, 117456, Singapore, 2Neuroradiology Department, National Neuroscience Institute, 308433, Singapore, 3Quantitative Image Processing Group, SBIC/A*STAR, 138671, Singapore, 4Department of Haematology-Oncology, National University Health System, 119074, Singapore, 5Cancer Science Institute, 117456, Singapore, 6Department of Radiology, National University of Singapore, 119074, Singapore
 
Individually measured arterial input functions (AIF) are critical for quantitative DCE MRI studies. Typical field of view (FOV) for breast DCE MRI do not cover major artery supplying the breast. We explored the feasibility of including the descending aorta in the FOV by using an additional surface coil placed on the back of patients for better proximity in positioning for direct measurements of AIF from the aorta. However, there are serious blood inflow effects at the descending aorta where blood flow is fast. Nevertheless, inflow effect is avoidable by extracting AIF at a more distal end along the aorta.

 
1479.   Accuracy of Longest Diameter Measurements of Ductal Carcinoma in Situ: a Comparison Study Between MRI and X-ray Mammography
Martin D Pickles1, Peter Gibbs1, and Lindsay W Turnbull1
1Centre for MR Investigations, University of Hull, Hull, East Yorkshire, United Kingdom

 
Re-operation rates post breast conserving surgery for DCIS pose a significant healthcare burden. Accurate estimation of DCIS extent should minimize re-operation rates. The aim of this study was to compare the accuracy of DCIS extent measurements from both x-ray mammography and MRI. Thirty-one participants underwent both x-ray mammography and MR assessment of DCIS. Measurements from both imaging modalities were compared to histopathology findings via Bland Altman plot methodology. MR estimates of DCIS extent were demonstrated to be more accurate than x-ray mammography and were less affected by certain histopathological features such as grade and necrosis.

 
1480.   MR relaxometry of silicone breast implants at 3.0T
Daniel M Krainak1, Brain Garra2, and Sunder S Rajan1
1CDRH/OSEL/DP, U.S. Food & Drug Administration, Silver Spring, MD, United States, 2CDRH/OSEL/DIAM, U.S. Food & Drug Administration, Silver Spring, MD, United States

 
We measured T1 and T2 relaxation times of silicone breast implants and phantom materials that may mimic breast tissue at 3 Tesla. The characterization of the relaxivities of silicone breast implants provides the opportunity for improved pulse sequence design for the diagnosis of implant rupture, leak, deformity, or degradation. To the authors’ knowledge, this is the first report of MR relaxations times (T1 and T2) for silicone breast implants at 3 Tesla.

 
1481.   High Resolution Breast MRI: Comparison of Coils in Patients with Breast Lesions
Anderson Nnewihe1, Bruce L Daniel1, Jafi Lipson1, Catherine Moran1, and Brian A Hargreaves1
1Radiology, Stanford University, Stanford, California, United States

 
The purpose of this study was to assess the potential diagnostic impact of very high-resolution breast MRI scans with a newly designed, fitted coil array versus lower resolution scans with a standard commercially available array. Preliminary results show better depiction of lesion morphology with the high resolution, but because the cases were clearly BIRADS 5, there was no difference in the diagnosis between the two resolutions. A wider range of cases is necessary to assess the diagnostic benefits of high-resolution breast MRI and further studies are underway.

 
1482.   TRICKS Based DCE-MRI: a Potential Route to Both High Spatial and High Temporal Resolution Breast Dynamic Datasets
Martin D Pickles1, Peter Gibbs1, Ersin Bayram2, and Lindsay W Turnbull1
1Centre for MR Investigations, University of Hull, Hull, East Yorkshire, United Kingdom, 2GE Healthcare, Waukesha, WI, United States

 
High temporal and high spatial resolution images are usually mutually exclusive. In this work, we demonstrate proof of principle, that both high spatial and temporal resolution DCE-MRI images can be acquired by utilising time resolved imaging of contrast kinetics (TRICKS). A pulse sequence was developed that combined TRICKS with a breast optimised 3D T1W gradient echo sequence. The resulting sequence was successfully acquired in multiple patients on a 3.0T scanner resulting in high spatial (1.0x1.0x1.4mm) and high temporal (10 second) resolution images. This work has demonstrated the ability to acquire both high spatial and high temporal resolution breast DCE-MRI datasets.

 
1483.   The use of texture analysis in the grading of breast cancer on MR images: preliminary findings
Shelley Waugh1,2, Richard Lerski1,2, Luc Bidaut2, and Alastair Thompson2,3
1Medical Physics, Ninewells Hospital, Dundee, Angus, United Kingdom, 2University of Dundee, Dundee, United Kingdom, 3Department of Surgery, Ninewells Hospital, Dundee, United Kingdom

 
This study considers the use of texture analysis in the grading of the two most common types of breast cancer- invasive ductal and infiltrative lobular cancers. It was believed that the underlying histological nature of cancer growth patterns used for staging would also result in textural features on MR imaging that could potentially allow classification between grades using computer-based texture analysis methods. Our preliminary results show classification between grades 1, 2 and 3 of invasive ductal cancer is possible and reliable, as is classification between grades 2 and 3 of lobular cancer. The co-occurrence matrix produced the best classification accuracy.

 
1484.   Evaluation of Bilateral Breasts Response to the Hormonal Fluctuation of Menstrual Cycle Using 3D MRI
Jeon-Hor Chen1,2, Siwa Chan3, Dah-Cherng Yeh4, Chih-Chen Kuo2, Jocelyn Lu1, Peter Fu1, MuQing Lin1, Orhan Nalcioglu1, and Min-Ying Lydia Su1
1Center for Functional Onco-Imaging, Department of Radiological Science, University of California, Irvine, California, United States, 2Department of Radiology, China Medical University Hospital, Taichung, Taiwan, 3Department of Radiology, Taichung Veterans General Hospital, Taichung, Taiwan, 4Department of Surgery, Taichung Veterans General Hospital, Taichung, Taiwan

 
Functional breast symmetry is less known. In this study we used 3D MRI to investigate how the bilateral breast tissues of healthy women respond to the hormonal fluctuations during a menstrual cycle. Twenty-four healthy premenopausal Asian women were studied. The obtained CV and maximal percent difference of FV in the left and the right breast of all subjects were compared. The results demonstrate that during the MC, the CV of the fibroglandular tissue volume measured from the left and the right breasts shows a strong correlation (r > 0.7), so as the maximal changes of FV. The fluctuations of the morphological parameters between the left and the right breasts were not significantly different. Since most of breast cancers occur unilaterally, it would be interesting to investigate whether the functional response of tissues in bilateral breasts to hormonal stimulation is associated with different risks in developing cancer.

 
1485.   Dynamic contrast-enhanced MRI of the breast at 7T and 3T; initial results of an intra-individual comparison of BI-RADS-MRI lesion assessment.
Bertine L. Stehouwer1, Dennis W.J. Klomp1, Peter R. Luijten1, Willem P.Th.M. Mali1, Maurice A.A.J. van den Bosch1, and Wouter B. Veldhuis1
1Radiology, University Medical Center, Utrecht, Utrecht, Netherlands

 
The purpose was to intra-individually compare BI-RADS-MRI assessment on 7T and 3T dynamic contrast-enhanced Breast MRI. Six patients with breast cancer were imaged on both field strengths. Two radiologists scored all exams. Image quality was scored to be at least sufficient for both field strengths. An inter-observer variability in the application of BI-RADS descriptors was observed. However, this did however not affect final assessment category, which was scored as at least suspicious in all cases.

 
1486.   Repeatability of magnetization transfer ratio measurements in the healthy breast at 3T
Lori R. Arlinghaus1,2, Richard D. Dortch1,2, Jennifer G. Whisenant1,2, Gregory D. Ayers3, Adrienne N. Dula1,2, Seth A. Smith1,2, and Thomas E. Yankeelov1,2
1Institute of Imaging Science, Vanderbilt University, Nashville, TN, United States, 2Department of Radiology and Radiological Sciences, Vanderbilt University, Nashville, TN, United States, 3Department of Biostatistics, Vanderbilt University, Nashville, TN, United States

 
Magnetization transfer (MT) imaging is sensitive to changes in the macromolecular content of tissue and is, therefore, gaining increased attention as a noninvasive approach to probe the complex tumor environment in cancer. The amount of magnetization transfer between macromolecules and the surrounding free water in tissue can be quantified by the MT ratio (MTR). In this study, we explore the repeatability of MTR measurements in the breast fibroglandular tissue of healthy controls at 3T to serve as a benchmark for future longitudinal studies of breast cancer treatment.

 
1487.   Changes in breast tumor perfusion during neoadjuvant chemotherapy: quantitative MRI in a clinical protocol
David A. Broadbent1, Daniel J. Wilson1, Nisha Sharma2, Barbara J. Dall2, Sarah E. Bacon1, Steven P. Sourbron3, and David L. Buckley3
1Medical Physics & Engineering, Leeds Teaching Hospitals NHS Trust, Leeds, West Yorkshire, United Kingdom, 2Radiology, Leeds Teaching Hospitals NHS Trust, Leeds, West Yorkshire, United Kingdom, 3Division of Medical Physics, University of Leeds, Leeds, West Yorkshire, United Kingdom

 
The introduction of quantitative MRI into clinical routine has often been hampered by the need to change and compromise clinical protocols. Here we show how quantitative data can be obtained with minimal interference in the case of DCE-MRI of the breast following neoadjuvant chemotherapy (NAC). Twenty patients were studied before and after 2 cycles of NAC. All studies were reported in the normal way with the addition of estimates of tumor perfusion, blood volume, capillary permeability and interstitial volume. Tumor perfusion decreased in responders more than in non-responders with no significant changes in the other parameters.

 
1488.   A New Strategy for Consistent Uniform Fat Suppression in Breast MR Imaging
Martin D Pickles1, Peter Gibbs1, Ersin Bayram2, Jessica Buzek2, Zhenghui Zhang2, and Lindsay W Turnbull1
1Centre for MR Investigations, University of Hull, Hull, East Yorkshire, United Kingdom, 2GE Healthcare, Waukesha, WI, United States

 
CHESS and spectrally selective inversion recovery fat nulling techniques are sensitive to B0 and B1 inhomogeneities which results in inconsistent non uniform fat suppression. The aim of this work is to develop a more robust fat suppression. By combining a Shinnar-Le Roux spectral spatial pulse with an Adiabatic SPectral-selective Inversion Recovery (ASPIR) pulse B1 insensitive water-only excitation was achieved. Dual shim volumes were employed to reduce B0 sensitivity. Traditional and spectral spatial ASPIR fat suppression techniques were acquired in multiple patients. In all cases, spectral spatial ASPIR fat suppression was deemed superior to the traditional method by a breast radiologist.

 
1489.   Validating lesion washout volume fraction as a biomarker for improving suspicious breast lesion characterization
Jie Huang1, Sarah Schafer1, Lori Hoisington1, and Gerald Aben1
1Department of Radiology, Michigan State University, East Lansing, MI, United States

 
This study validated lesion washout volume fraction as an MRI biomarker for improving the characterization of suspicious contrast-enhancing breast lesions. Using a sample consisting of 94 contrast-enhanced lesions with histopathology reports, the study found that the washout volume fraction was significantly larger for the malignant tumors than the benign lesions, reflecting the hypervascularity associated with tumor angiogenesis. It provides an additional MRI biomarker for improving the characterization of suspicious contrast-enhancing breast lesions, and the biomarker has the potential to improve the computer-based assessment in breast MRI.

 
1490.   Dual Echo Steady State Quantitative T2-mapping in the Breast
Catherine Judith Moran1, Kristin L Granlund1,2, Bruce L Daniel1, Bragi Sveinsson1,2, Ernesto Staroswiecki1,2, Marcus T Alley1, and Brian A Hargreaves1
1Radiology, Stanford University, Stanford, CA, United States, 2Electrical Engineering, Stanford University, Stanford, CA, United States

 
Dual echo steady state (DESS) acquisitions can be utilized to acquire high-resolution, quantitative T2 maps in clinically feasible scan times, thus facilitating investigation of T2 properties of in vivo tissues. In this work we present the results of an initial investigation of DESS quantitative T2 mapping in the breast. DESS T2 maps are assessed in normal, benign and malignant in vivo breast tissue and measured T2 values are compared to those previously reported for tissues in the breast.

 
1491.   Development of a T2 Weighted 3D CUBE Inversion Recovery Fat Nulled Sequence for Breast Imaging
Martin D Pickles1, Peter Gibbs1, Ersin Bayram2, Donglai Huo2, and Lindsay W Turnbull1
1Centre for MR Investigations, University of Hull, Hull, East Yorkshire, United Kingdom, 2GE Healthcare, Waukesha, WI, United States

 
While the sensitivity of breast MRI is high the specificity is somewhat lower. T2W sequences help to increase the specificity of breast MR. The aim of this work was to develop a 3D T2W fat nulled sequence. Additionally, by substituting the traditional CHESS fat nulling pulse with an IR technique improved fat nulling was anticipated. By combining a 3D CUBE FSE sequence with an IR pulse bilateral sagittal images of the breast (5min20sec with a 0.875x0.875x2.4mm voxel size) were obtained. The potential of the sequence was observed in the robust fat nulled high spatial resolution images obtained in 10 datasets.

 
1492.   In-vivo water, fat and silicone separation using a fast multi-echo TSE acquisition
Karl-Heinz Herrmann1, Tim Sprenger1, Werner A Kaiser2, and Jürgen R Reichenbach1
1IDIR I, Medical Physics Group, Jena University Hospital, Jena, Germany, 2IDIR I, Jena University Hospital, Jena, Germany

 
A fast multi-echo TSE sequence is proposed for Dixon based water, fat and silicone separation. The sequence acquires 5 echoes, using bipolar gradients, within each refocusing interval. To correct the phase errors introduced by the bipolar readouts, the central k-space line is acquired for each echo in two additional refocusing intervals after the imaging echo train. There the readout gradients in the second interval are inverted to provide phase calibration data. The spectral separation was performed with a region-growing stabilized VARPRO implementation. One in-vivo dataset of a patient is shown and the separation proved robust against the B0 inhomogeneities present in the patient.

 
1493.   High B1 dutycycle in bilateral breast imaging at 7T
Michel G.M. Italiaander1, Peter J. Nijholt1, Oliver Kraff2, Alexander Raaijmakers1, Bertine Stehouwer1, Peter R. Luijten1, and Dennis W.J. Klomp1
1Imaging division, University Medical Center, Utrecht, Utrecht, Netherlands, 2Erwin L. Hahn Institute for MRI, University Duisburg-Essen, Essen, Germany

 
Detection and staging of breast cancer can benefit from increased SNR that is potentially available at high magnetic fields like 7T. However, as strong T1 weighting in CE-MRI is required, a high density of strong flip angles need to be applied, that generally will be limited due to SAR constrains. Therefore we propose the use of efficient quadrature surface arrays to maximize CE-MRI efficiency at 7T in bilateral breast imaging while remaining within SAR guidelines. The relatively uniform CE-MRI sensitivity in both breasts, and very strong T1 weighting is demonstrated in a volunteer and in a patient with breast cancer.

 
1494.   Differentiation of Benign from Malignant Non-Mass-Like-Enhancement in BRCA 1 Mutation Carriers Using Quantitative Kinetic Analysis
Alana R. Amarosa1, Linda Moy1, Amy Melsaether1, Jason McKellop1, Melanie Moccaldi1, Jin Zhang1, and Sungheon Kim1
1Radiology, NYU School of Medicine, New York, New York, United States

 
The purpose of this study was to investigate the ability of quantitative kinetic analysis to identify malignant enhancing lesions on MRI in BRCA1 patients. In this retrospective study, we included 27 BRCA1 mutation carriers who underwent MRI guided biopsy. A linear principal component analysis (PCA) transformation was used to measure background parenchymal enhancement (BPE). Percent enhancement (PE) and early enhancement rate (S23) were measured in both lesion and BPE. PE and S23 for BPE were compared to those for malignant and benign lesions. Using our quantitative analysis, we found PE to be helpful in distinguishing between benign and malignant lesions.

 
1495.   Peak Enhancement and Time to Peak Enhancement May Differentiate Mammographically and Sonographically Occult Breast Malignancies from Normal Enhancing Breast Parenchyma
Amy Melsaether1, Nathaniel Margolis1, Alana R. Amarosa1, Melanie Moccaldi1, Samantha Heller1, Sungheon Kim1, and Linda Moy1
1Radiology, NYU School of Medicine, New York, New York, United States

 
Dynamic contrast enhanced breast MRI can detect breast cancers that are occult on mammography and sonography. The enhancement pattern of such cancers relative to breast parenchyma has never been quantified. We compared 21 mammographically and sonographically occult breast cancers to control areas of parenchyma. In malignant lesions compared to controls, there was a shorter time to peak and a greater peak enhancement, but no significant difference in signal enhancement ratio. Our findings suggest that time to peak and peak enhancement can help differentiate benign breast parenchyma from otherwise occult malignant lesions, possibly reducing the need for biopsy.

 
1496.   Peak Enhancement of up to 1.0cm Breast Masses May Help Differentiate Cancers from Benign Entities
Amy Melsaether1, Alana R. Amarosa1, Nathaniel Margolis1, Melanie Moccaldi1, Samantha Heller1, Sungheon Kim1, and Linda Moy1
1Radiology, NYU School of Medicine, New York, New York, United States

 
Malignant breast masses measuring up to 1.0cm are frequently occult on conventional imaging and demonstrate overlapping morphology with benign entities on dynamic contrast enhanced MRI. We therefore investigated whether kinetic markers including time to peak enhancement, peak enhancement, and signal enhancement ratio (SER) can be used to separate these malignancies from benign findings. Thirty up to 1.0cm masses and foci were analyzed for these variables using DynaCAD. Results demonstrate a trend towards increased peak enhancement in malignant masses and suggest benign biopsies could be decreased by establishing a minimum enhancement threshold for biopsy.

 
1497.   Detection of breast micro-calcifications at high-field MRI.
Bertine L. Stehouwer1, Hendrik de Leeuw2, Peter R. Seevinck2, Fredy Visser1,3, Peter R. Luijten1, Dennis W.J. Klomp1, Paul J. van Diest4, Chris J.G. Bakker2, and Wouter B. Veldhuis1
1Radiology, University Medical Center, Utrecht, Utrecht, Netherlands, 2Image Sciences Institute, University Medical Center, Utrecht, Netherlands, 3Philips Healthcare, Best, Netherlands, 4Pathology, University Medical Center, Utrecht, Utrecht, Netherlands

 
We investigated the ability of high-field MRI to detect breast micro-calcifications in a phantom and ex-vivo set-up by exploiting susceptibility differences between calcifications and glandular tissue. Magnitude images depicted several field disturbances, but were clearly distorted by B1-inhomogeneities and, moreover, did not allow characterization of the field inhomogeneities. Phase derivative images were not hampered by B1-inhomogeneities and showed a high sensitivity for detecting the characteristic six-lobed blooming pattern which is seen in case of calcifications. The calcifications were confirmed by CT and mammography, respectively. This study shows the feasibility of the detection of breast micro-calcifications using high-field MRI.

 
1498.   Consistency of Breast Density Measured in Four Different MR Scanners
Jeon-Hor Chen1,2, Siwa Chan3, Dah-Cherng Yeh4, Chin-Kai Chang2, Li-Kuang Chen1, Wei-Fan Pan2, MuQing Lin1, Orhan Nalcioglu1, and Min-Ying Lydia Su1
1Center for Functional Onco-Imaging, Department of Radiological Science, University of California, Irvine, California, United States, 2Department of Radiology, China Medical University Hospital, Taichung, Taiwan, 3Department of Radiology, Taichung Veterans General Hospital, Taichung, Taiwan, 4Department of Surgery, Taichung Veterans General Hospital, Taichung, Taiwan

 
For assessing the association between MRI-based density and cancer risk, a large dataset is required and combining MRI from multiple centers is the only feasible way to achieve this goal. The purpose of this work is to compare the measurement consistency of breast volume, fibroglandular tissue volume and percent density using 4 different MR scanners. Thirty-four healthy Asian female subjects were studied at two 1.5T and two 3T scanners. The correlation of FV between each pair of two MR scanners was very high, with all R2 ≥ 0.99. For some cases, however, the measurement variation was high, which was due to a large difference of one scanner compared to the other three scanners. The results show that when MR pulse sequences are optimized, and a well-developed segmentation method is used, consistent density parameters from the same women can be obtained on images acquired using different MR scanners. The positioning difference may account for some variation, and further optimization work may be developed to minimize its impact.

 
1499.   Accelerated DCE Breast Imaging with Isotropic Spatial Resolution and a Small Temporal Footprint
Leah C Henze-Bancroft1, Frederick Kelcz2, Kevin M Johnson3, and Walter F Block1,3
1Department of Biomedical Engineering, University of Wisconsin - Madison, Madison, WI, United States, 2Department of Radiology, University of Wisconsin - Madison, Madison, WI, United States, 3Department of Medical Physics, University of Wisconsin - Madison, Madison, WI, United States

 
We present initial results of our attempt to determine whether a tight temporal footprint (15 s) and spatial resolution (1 mm isotropic) can better characterize heterogeneously enhancing lesions in the breast. Eight volunteers underwent a standard clinical DCE and a rapid 3D radial (VIPR) SPGR DCE over two days of scanning. The 3D-VIPR SPGR method was able to provide good visualization of a lesion in three orthogonal reformats displaying heterogeneous enhancement as well as good depiction of the margin enhancement. To date this method has only been used on unilateral exams but should be expandable to bilateral imaging.
 
Traditional Poster Session - Cancer

Prostate
Click on to view the abstract pdf. Click on to view the poster (Not all posters are available for viewing.)
 
Wednesday 9 May 2012
Exhibition Hall  10:00 - 12:00

1500.   1H MRSI for in vivo lactate detection in prostate cancer
Thiele Kobus1, Jack Van Asten1, Alan Wright1, Arend Heerschap1, and Tom Scheenen1
1Radiology, Radboud University Nijmegen Medical Centre, Nijmegen, Gelderland, Netherlands

 
In this study the use of 1H MRSI for the detection of lactate in the prostate was evaluated with the use of a semi-LASER sequence. No convincing lactate signal was detected in patients with highly aggressive prostate cancer. The minimal detectable lactate level was determined and estimated to be around 3 mM.

 
1501.   Quantification of prostate metabolites at 3 T using water as the internal reference
Jan Weis1, Francisco Ortiz-Nieto1, and Håkan Ahlström1
1Department of Radiology, Uppsala University Hospital, Uppsala, Sweden

 
Metabolite concentrations may be helpful in monitoring treatment efficacy, and relapse probability associated with prostate cancer. Single-voxel spectroscopy of the prostate at 3 T with surface coil was performed. Metabolite-to-unsuppressed water spectral intensity ratios of healthy volunteers and patients with biopsy-proven prostate cancer were determined with an LCModel. Mean normalized spectra, LCModel fits, and absolute concentrations of Cho, Cr, and Cit were computed for normal volunteers and cancer patients.

 
1502.   Contrast Agent-Free High Resolution MRI for Prostate Cancer Detection Using a Two Compartment Inversion Recovery (TCIR) Technique.
Patrik Zamecnik1, Grzegorz Bauman2, Julien Dinkel1,3, Heinz-Peter Schlemmer1, and Thomas Gaass4
1Radiology, German Cancer Research Center (DKFZ), Heidelberg, Germany, 2Department of Medical Physics, German Cancer Research Center (DKFZ), Heidelberg, Germany,3Department of Radiology, Massachusetts General Hospital, Boston, Germany, 4Zentralinstitut für Medizintechnik, Technische Universität München, Garching, Germany

 
Validation of the feasibility of TCIR (two compartment inversion recovery) contrast agent-free approach for prostate cancer detection by comparison with the standard T2w, DCE- and DWI-sequences. Using the TCIR technique it was possible to generate good quality high-resolution maps of the fractional blood volume in the prostate without using a contrast agent. TCIR has a high potential for prostate cancer detection because of its high spatial resolution and sensitivity, first of all in patients, which cannot be examined using contrast media.

 
1503.   Deformable Registration for Recovering Image Distortions in DWI MRI of the Prostate at 3T
Andriy Fedorov1, Luis Ibanez2, Kemal Tuncali1, Robert V Mulkern1,3, William M Wells1, Clare Tempany4, and Fiona Fennessy1
1Department of Radiology, Brigham and Women's Hospital, Boston, MA, United States, 2Kitware Inc, Clifton Park, NY, United States, 3Department of Radiology, Children's Hospital, Boston, MA, United States, 4Brigham and Women's Hospital, Boston, MA, United States

 
There is strong evidence of the value in using multiparametric MRI (mpMRI) to characterize prostate cancer. However, quantitative analysis of mpMRI is challenging due to the differences in resolution and acquisition-related distortions, which are particularly strong while imaging prostate using endorectal coil placed in air-filled balloon at 3T. Herein we propose a non-rigid registration approach fine-tuned to compensate for such artifacts by incorporating the prior knowledge about the nature of the distortion into the method. We evaluate the robustness and accuracy of the approach, and employ it to quantify distortions present in the DWI MRI of the prostate.

 
1504.   In-vivo 3T and ex-vivo 7T Diffusion Tensor Imaging of Prostate Cancer - Correlation With Histology
Carlos Felipe Uribe Munoz1,2, Edward C Jones3, Silvia D. Chang4, Larry Goldenberg5,6, and Piotr Kozlowski2,5
1Physics & Astronomy, University of British Columbia, Vancouver, British Columbia, Canada, 2MRI Research Centre, University of British Columbia, Vancouver, British Columbia, Canada, 3Pathology and Laboratory Medicine, University of British Columbia, Vancouver, British Columbia, Canada, 4Radiology, University of British Columbia, Vancouver, British Columbia, Canada, 5Vancouver Prostate Centre, Vancouver, British Columbia, Canada, 6Urological Sciences, University of British Columbia, Vancouver, British Columbia, Canada

 
Diffusion Tensor Imaging (DTI) has been applied in prostate cancer diagnosis. It has been well accepted that water apparent diffusion coefficient (ADC) has a lower value in tumours than in healthy prostatic tissue, while fractional anisotropy (FA) has been reported to be higher, lower, and unchanged. Histology slices were registered with in-vivo and ex-vivo DTI images, and average values of ADC and FA were calculated for certain regions of interest. No significant differences in FA between normal peripheral zone and prostatic carcinoma were found suggesting that FA is not likely to contribute to diagnostic capabilities of DTI in prostate cancer.

 
1505.   Correlating prospective and histology-matched ADC histograms with extra-capsular extension in prostate cancer
Edward M Lawrence1, Tristan Barrett1, Andrew N Priest1, Vincent J Gnanapragasam2, Ferdia A Gallagher1, Andrew J Patterson1, Anne Warren3, and Evis Sala1
1Clinical MRI Unit, Addenbrooke's Hospital, Cambridge, United Kingdom, 2Urology, Addenbrooke's Hospital, Cambridge, United Kingdom, 3Histopathology, Addenbrooke's Hospital, Cambridge, United Kingdom

 
1506.   Assessing Prostate Cancer Growth with Citrate Measured by Intact Tissue Proton Magnetic Resonance Spectroscopy
Rosa Rossling1, Rene Dittrich1, Emily Decelle2, Chin-Lee Wu2, W Scott McDougal2, and Leo L Cheng2
1Charité Universitätsmedizin, Berlin, Germany, 2Massachusetts General Hospital, Boston, MA, United States

 
Implementation of PSA testing has increased the number of early diagnosed cases of prostate cancer. This shift in diagnosis necessitates the evolution of pathology and other biomolecular markers to identify and categorize early stages of the disease. In previous studies, citrate has been identified as a potential marker for malignancy and aggressiveness. Here we correlate citrate levels with PSA velocity, PSA density, percent free PSA, which we are using as surrogate markers for PCa growth and aggressiveness.

 
1507.   Combination of MR spectroscopic and diffusion weighted imaging of the prostate for the prediction of tumor aggressiveness
Gregor Thörmer1, Josephin Otto1, Christian Schröder1, Nikita Garnov1, Martin Reiss-Zimmermann1, Lars-Christian Horn2, Minh Do3, Jens-Uwe Stolzenburg3, Michael Moche1, Thomas Kahn1, and Harald Busse1
1Dept. of Diagnostic and Interventional Radiology, Leipzig University Hospital, Leipzig, Saxony, Germany, 2Institute of Pathology, Division of Breast, Urogenital and Perinatal Pathology, University of Leipzig, Leipzig, 3Dept. of Urology, Leipzig University Hospital, Leipzig, Saxony, Germany

 
Active surveillance (AS) is currently discussed as an alternative to radical therapy for patients with low-risk prostate cancer. This option requires an accurate and reproducible technique to monitor the progress of the disease. Transrectal ultrasound-guided biopsy is only moderately suited because of its invasive nature and a substantial amount (40%) of undergrading. Multiparametric MRI, on the other hand, can provide quantitative parameters of tissue function that may help to assess cancer aggressiveness. This preliminary work evaluates the predictive value of combined DWI and MR spectroscopic parameters to discriminate indolent from aggressive carcinoma.

 
1508.   Metabolomic characterization of human prostate cancer with intact tissue MRS
Rosa Rossling1, Johannes Kurth1, Emily Decelle2, Chin-Lee Wu2, W Scott McDougal2, and Leo L Cheng2
1Charité Universitätsmedizin, Berlin, Germany, 2Massachusetts General Hospital, Boston, MA, United States

 
A 2005 publication on the investigations of human prostate cancer metabolomics led to two major conclusions that metabolomic profiles can differentiate tissue specimens with and without cancer glands, as well as patient pathological stages. However, this study only proposed the metabolomic structure from the analysis of a training cohort and did not evaluate another independent testing cohort. In this study we followed the concepts of previous report and analyzed tissue samples from prostate cancer patients with constructions of training and testing cohorts.

 
1509.   Machine learning for target selection in MR-guided prostate biopsy: A preliminary study
Mehdi Moradi1, Andriy Fedorov1, William M Wells1, Kemal Tuncali1, Sandeep N Gupta2, Fiona M Fennessy1, and Clare M Tempany1
1Radiology, Brigham and Women's Hospital - A Teaching Affiliate of Harvard Medical School, Boston, MA, United States, 2GE Global Research Center, Niskayuna, NY

 
We propose to use machine learning to enhance the process of target selection for 3T MR-guided transperineal prostate biopsy. Support vector machine and Gaussian classifiers with different combinations of diffusion and DCE MRI are examined. Training is performed on data from 13 prostatectomy cases with histologically confirmed cancer in the peripheral zone. The trained classifier was used to determine the outcome of in ten PZ biopsy samples from five patients. The Bayesian classifier with ADC as the only feature resulted in the ROC area of 0.964 in leave-one-patient-out cross-validation on the training dataset. The outcomes of eight of the ten biopsies, including all three cancer samples, were correctly determined.

 
1510.   Value of magnetic resonance imaging for the local staging of prostate cancer at 3 T
Josephin Otto1, Gregor Thörmer1, Matthias Seiwerts1, Jochen Fuchs1, Nikita Garnov1, Lars-Christian Horn2, Harald Busse1, Thomas Kahn1, and Michael Moche1
1Department of Diagnostic and Interventional Radiology, University Hospital, Leipzig, Saxony, Germany, 2Institute of Pathology, University Hospital, Leipzig, Saxony, Germany

 
Prostate cancer is characterized by a high incidence but relatively low mortality. Disease prediction, risk stratification and therapeutical decision of histopathologically confirmed prostate cancer are commonly obtained by nomograms, which have a relatively low predictive value. Multiparametric MRI, in contrast, can provide detailed information of unilateral or bilateral extracapsular extension and seminal vesicle invasion, which is important for patients selected for nerve-sparing surgery. The high specificities and relatively high sensitivities observed here suggest that 3 T MRI with an endorectal coil is a suitable diagnostic tool for the local staging of prostate cancer.

 
1511.   Assessment of Biexponential T1 decay in prostate tissue.
Tryggve Holck Storås1, and Kjell-Inge Gjesdal2
1Intervention Centre, Oslo University Hospital, Oslo, Norway, Norway, 2Sunnmøre MR-klinikk, Ålesund, Norway, Norway

 
Prostate tissues have been shown to exhibit multiexponential T2 and ADC decay. In this paper we used a multiecho interleaved SE and IR technique to assess T1 and T2 values of the two compartments. We found a long T1 component of about 3000 ms and a short T1 component of about 1200ms.

 
1512.   Software tool for the simultaneous display and automated analysis of multiparametric MRI data of the prostate
Harald Busse1, Josephin Otto1, Gregor Thörmer1, Nikita Garnov1, Thomas Kahn1, and Michael Moche1
1Diagnostic and Interventional Radiology Department, Leipzig University Hospital, Leipzig, Germany

 
A multiparametric MRI examination of the prostate typically generates a large number of individual images (over 500) and MR spectra (several hundreds). Analysis and review of these data can be a laborious and time-consuming procedure for the radiologist. This work describes and evaluate a non-commercial software solution for the analysis and simultaneous display of data from T2-weighted, diffusion-weighted, dynamic contrast-enhanced (DCE) and chemical shift imaging (CSI). Besides an automated calculation of semiquantitative DCE parameter maps, the tool also allows for a transparent overlay of selected low-error metabolite ratios from CSI data analyzed with a well-established spectroscopy software (LCModel).

 
1513.   Comparisons of prostate cancer tissue metabolic intensities and metabolomic profiles from African American and Caucasian patients
Emily Decelle1, Phillip Knape2, Chin-Lee Wu1, W Scott McDougal1, and Leo L Cheng1
1Massachusetts General Hospital, Boston, MA, United States, 2Charité Universitätsmedizin, Berlin, Germany

 
Prostate cancer exhibits a racial disparity such that African American men have a significantly higher incidence and mortality rate than Caucasian men. The possible ethological or biological factors responsible for these differences remain unknown but may reveal much about the disease that has become the most frequently diagnosed cancer in men. In this study, we compare tissue metabolic intensities and the metabolomic profiles of prostate cancer from African American patients with those from matched Caucasian patients in order to expose metabolic similarities and differences between the two patient populations.

 
1514.   Dynamic contrast enhanced MR imaging for the assessment of prostate cancer aggressiveness at 3T
Eline Vos1, Geert Litjens1, Thiele Kobus1, Thomas Hambrock1, Christina Hulsbergen-Van de Kaa2, Henkjan Huisman1, and Tom Scheenen1
1Radiology, Radboud University Nijmegen Medical Center, Nijmegen, Netherlands, 2Pathology, Radboud University Nijmegen Medical Center, Nijmegen, Netherlands

 
Dynamic contrast enhanced MR imaging for retrospective assessment of prostate cancer aggressiveness was explored in fifty-one patients at 3T with histopathological Gleason scores of resected prostates as the gold standard. Calibration for pharmacokinetic modeling was done by using non-cancer peripheral zone tissue to estimate patient-specific arterial input functions. For semi-quantitative parameters LateWash and Relative Enhancement there was a significant difference between low aggressive and high aggressive prostate cancer in the peripheral zone. For quantitative parameters Ktrans, Kep and Ve there was no correlation with aggressiveness, however, they showed significant difference between non-cancer tissue and prostate cancer for the peripheral zone

 
1515.   Visualization of prostate fibromuscular stromal matrix using ex-vivo high-resolution DTI tractography
Nyoman D. Kurniawan1, Gary Cowin1, Paul Sved2, Geoffery Watson3, and Roger Bourne4
1Centre for Advanced Imaging, University of Queensland, Brisbane, Queensland, Australia, 2Department of Urology, Royal Prince Alfred Hospital, The University of Sydney, Sydney, New South Wales, Australia, 3Department of Anatomical Pathology, Royal Prince Alfred Hospital, University of Sydney, Sydney, New South Wales, Australia, 4Discipline of Medical Radiation Sciences, Faculty of Health Sciences, The University of Sydney, Sydney, New South Wales, Australia

 
16.4T high-resolution diffusion tensor imaging (DTI) of fixed prostate cancer biopsy has revealed distinct microscopic diffusion environments and tissue architecture consistent with that seen on light microscopy. In this study, we present a new methodology for the visualization of fibromuscular stromal matrix from a prostate biopsy using high-resolution DTI-tractography.

 
1516.   The Initial Clinical Application of Arterial Spin Labeling Perfusion MRI in Prostate Cancer
Wenchao Cai1, Feiyu Li1, 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

 
Introduction:Pulsed arterial spin labeling (PASL) MRI is a non-invasive imaging tool capable of quantitatively measuring the microvascular perfusion characteristics of tissue. Purpose:We applied the PASL technique to detect the prostate cancer and to compare the differences blood flow(BF) values between the malignant and normal prostate peripheral zones. Methods:Six patients with pathologically confirmed prostate cancer were recruited to undergo the PASL examination with different invertion time(TI 1000/1200/1400/1600msec).Results: The mean BFs determined by PASL MRI with different TI in the prostate cancer were significantly higher than those in noncancerous regions (P<0.05, Paired T-test).Conclusion: This study demonstrates that PASL sequence can be used to evaluate the difference of BF value between cancer and noncancerous tissue in prostate.

 
1517.   A Comparative Study of High-Resolution vs. Conventional Diffusion-Weighted Imaging of the Prostate at 3T
Maysam Jafar1, Sharon Giles2, Veronica Morgan2, and Nandita deSouza3
1Clinical Magnetic Resonance, Institute of Cancer Research, London, Surrey, United Kingdom, 2Clinical Magnetic Resonance, Royal Marsden NHS Foundation Trust, London, United Kingdom, 3Clinical Magnetic Resonance, Institute of Cancer Research and Royal Marsden NHS Foundation Trust, London, United Kingdom

 
In prostate cancer DWI is additionally proving useful as a predictive biomarker of disease aggressiveness but severe artefacts and low resolution can hamper accurate quantification and reduce value of the biomarker particularly where suspected lesions are <1cm2. High-resolution DWI techniques potentially improve detection of small lesions, but suffer from reduced SNR compared to conventional techniques. The purpose of this study therefore was to investigate the differences in estimated ADC values in normal prostate and prostate cancer derived from a conventional diffusion-weighted protocol vs. a high-resolution protocol.
 
Traditional Poster Session - Cancer

Cancer Models - Novel Contrast
Click on to view the abstract pdf. Click on to view the poster (Not all posters are available for viewing.)
 
Wednesday 9 May 2012
Exhibition Hall  10:00 - 12:00

1518.   Evaluation of Melanoma Xenograft through Chemical Exchange Saturation Transfer Imaging: A Preliminary Report
Mohammad Haris1, Kavindra Nath2, Anup Singh1, Kejia Cai1, David S Nelson2, Dennis B Leeper3, Hari Hariharan1, Jerry D Glickson2, and Ravinder Reddy1
1Radiology, University of Pennsylvania, Philadelphia, Pennsylvania, United States, 2Molecular Imaging Lab, University of Pennsylvania, 3Radiation Oncology, Thomas Jefferson University Hospitals

 
In this preliminary study, we explored the chemical saturation transfer effect from amino acids particularly glutamate and alanine present in the mouse model of melanoma and image them at high spatial resolution and discuss the potential significance of using this method in the management of human melanoma.

 
1519.   Magnetization Transfer MRI in Pancreatic Cancer Xenograft Models
Weiguo Li1, Zhuoli Zhang1, Jodi Nicolai1, Guang-Yu Yang2, Reed Omary1, and Andrew Larson1
1Radiology, Northwestern University, Chicago, IL, United States, 2Pathology, Northwestern University, Chicago, IL, United States

 
Magnetization transfer (MT) MRI measurements were performed in 3 pancreatic ductal adenocarcinoma (PDAC) mouse xenograft models. For each of 28 PDAC xenografts, magnetization transfer ratios (MTR) were calculated and compared to histologic fibrosis levels from reference standard trichrome staining. MTR measurements were well correlated to quantitative fibrosis levels (r = 0.69, P = 0.01). Results indicated that MTR measurements offer the potential to serve as a valuable in vivo biomarker of desmoplasia in PDAC.

 
1520.   Look-Locker Arterial Spin Labelling (ASL) of Liver Metastases
Rajiv Ramasawmy1,2, Simon Walker-Samuel1, Adrienne Campbell1, Sean P Johnson2, Jack Wells1, Rosamund B Pedley2, and Mark F Lythgoe1
1UCL Centre for Advanced Biomedical Imaging, Division of Medicine and Institute of Child Health, University College London, London, United Kingdom, 2Cancer Institute, University College London, London, United Kingdom

 
Vascular targeting therapies induce acute changes in tumour perfusion, and imaging biomarkers of response are of particular interest in the clinic. We present a novel use of a respiratory-triggered flow-sensitive alternating inversion recovery (FAIR) Look-Locker arterial spin labelling (ASL) technique to measure perfusion within orthotopic liver metastases. Perfusion within the metastases was measured to be significantly lower than in normal liver tissue. We argue that this technique is suitable for follow-up and repeated measurements to track patient response as it does not require injected contrast agents.

 
1521.   Quantification of Necrosis in Animal Tumor Model using K-Means Clustering of ADC
Louisa Bokacheva1, Khushali Kotedia1,2, Megan Reese1, Carl Le1, Jason Koutcher1,3, and Sean Carlin1,3
1Department of Medical Physics, Memorial Sloan-Kettering Cancer Center, New York, New York, United States, 2Baylor College of Medicine, Houston, Texas, United States,3Department of Radiology, Memorial Sloan-Kettering Cancer Center, New York, New York, United States

 
Six athymic nu/nu rats bearing HT29 human colorectal xenograft tumors (700 mm3) were imaged at 7 T twice and diffusion-weighted images were acquired at five b-values between 0 and 900 s/mm2. After imaging, rats were sacrificed, tumors were excised and histologically analyzed to determine the necrotic fraction. ADC voxel maps were calculated using monoexponential equation. K-means clustering was applied to the ADC data pooled from all tumors and ADC maps were segmented into two clusters: (1) viable and (2) necrotic. The threshold ADC value between clusters was found to be 0.88x10-3 mm2/s. The fractional area of the necrotic cluster 2 correlated well with the histological necrotic fraction (R2 = 0.91), although for half of the tumors, necrotic fraction was slightly overestimated. The spatial agreement between the cluster maps and histological necrotic areas was better for tumors with larger contiguous necrotic areas than for tumors with multiple small necrotic regions.

 
1522.   Mapping of Oxygen By Imaging Lipids relaxation Enhancement (MOBILE) in experimental tumor models: comparison with R2*, R1 H2O, and OxyLite fiber optic probes.
Benedicte F Jordan1, Julie Magat1, Elif Ozel1, Florence Colliez1, Anne-Catherine Fruytier1, Valerie Marchand1, Lionel Mignion1, Caroline Bouzin2, Olivier Feron2, and Bernard Gallez1
1Biomedical Magnetic Resonance Group, Université Catholique de Louvain, Brussels, Belgium, 2Pole of Pharmacotherapy, Université Catholique de Louvain, Brussels, Belgium

 
There is a critical need for methods able to monitor dynamically and noninvasively tumor oxygenation. The purpose of the current work was to compare the MOBILE technique, a method developed to map variations in oxygenation based on the changes in the relaxation properties of the tissue lipids by exploiting the higher solubility property of oxygen in lipids than in water, with R2*, R1 H2O, and simultaneous quantitative oxygen measurements using fluorescence quenching fiber optic probes. Changes in tumor oxygenation were induced by an hyperoxic breathing challenge in order to determine correlations between the response assessed using each technique.

 
1523.   Diagnostic Value of R2* in identifying ALK mutations in transgenic murine models of neuroblastoma
Laura Glass1,2, Yann Jamin1, Rani George3, Louis Chesler2, and Simon P Robinson1
1CRUK and ESPRC Cancer Imaging Centre, The Institute of Cancer Research, Sutton, London, United Kingdom, 2Paediatric Oncology, The Institute of Cancer Research, Sutton, London, United Kingdom, 3Pediatric Oncology, Harvard University School of Medicine, Dana Faber Cancer Institute, Boston, MA, United States

 
Neuroblastoma is the most common extra-cranial solid tumour of infancy. It is well established that MCYN amplified patients are strongly correlated with a poor prognosis and increased likelihood of disease relapse. More recently, patients with ALK mutated cases of neuroblastoma have been associated with a very poor prognosis and an ultra-high risk of disease relapse. This study uses R2* to identify the presence of an ALK mutation in transgenic murine models. If this phenomenon translates to clinical situation, multi-gradient echo sequences could be incorporated into diagnostic scanning in neuroblastoma to stratify patients for targeted therapy.

 
1524.   Evaluation of MR Imaging Biomarkers of the Diffuse Infiltrative Phenotype in Orthotopic Brain Tumours
Jessica K. R. Boult1, Lara Perryman2,3, Alexa Jury2,3, Gary Box3, Paola Porcari1,4, Sergey Popov2,3, Suzanne A. Eccles3, Chris Jones2,3, and Simon P. Robinson1
1CRUK and EPSRC Cancer Imaging Centre, The Institute of Cancer Research and Royal Marsden NHS Foundation Trust, Sutton, Surrey, United Kingdom, 2Division of Molecular Pathology, The Institute of Cancer Research, Sutton, Surrey, United Kingdom, 3CRUK Cancer Therapeutics Unit, The Institute of Cancer Research, Sutton, Surrey, United Kingdom, 4Physics Department, Sapienza University of Rome, Rome, Italy

 
Delineation of diffuse infiltrative gliomas, in which the blood brain barrier remains intact, using conventional Gd-DTPA-enhanced MRI can be problematic. We aimed to develop a model of diffuse infiltrative brain tumours and to interrogate it using a multiparametric MRI approach. Primary paediatric glioblastoma xenografts presented with a diffuse growth pattern, clinically relevant observations on T2-weighted and FLAIR images, and demonstrated no signal change following Gd-DTPA or USPIO administration. Areas of invasion in MDA-MB-231 tumours in the brain correlated with regions of low fBV and Gd-DTPA-induced Capital Greek DeltaR1. These tumours represent an ideal platform for evaluating novel therapeutics targeted towards invasive disease.
 
Traditional Poster Session - Cancer

Cancer Models - DCE
Click on to view the abstract pdf. Click on to view the poster (Not all posters are available for viewing.)
 
Wednesday 9 May 2012
Exhibition Hall  10:00 - 12:00

1525.   A new Reference Agent Model for DCE-MRI that exploits selective detection of two 19F MRI contrast agents
Julio Cárdenas-Rodríguez1, Christy M Howison2, Terry O Matsunaga3, and Mark D. Pagel4
1Chemistry and Biochemistry, TheUniversity of Arizona Cancer Center, University of Arizona, Tucson, AZ - Arizona, United States, 2Arizona Research Labs, University of Arizona, Tucson, Arizona, United States, 3Radiology, University of Arizona, Tucson, Arizona, United States, 4Departments of Biomedical Engineering, Chemistry and Biochemistry, The University of Arizona Cancer, University of Arizona, Tucson, Arizona, United States

 
The Reference Region Model has been proposed as an alternative method for evaluating DCE-MRI results without requiring an AIF, yet this method cannot account for changes in blood flow and hematocrit that affect the evaluation of vascular permeability. Instead of comparing DCE of a single contrast agent in two tissues, we propose a new model that compares two contrast agents in a single tissue, termed the Reference Agent Model. This report describes the selective detection of two 19F contrast agents in vivo under dynamic and multislice conditions, and opens the possibility of estimating the relative permeability of two CA because this new model is independent of blood flow and hematocrit.

 
1526.   
The assessment of cellular packing heterogeneity in brain tumors using DSC-MRI
Natenael Semmineh1, and C. Chad Quarles1
1Institute of Imaging Science, Vanderbilt University, Nashville, TN, United States

 
The use of DSC-MRI in brain tumors is known to be influenced by contrast agent extravasation, which can result in additional extravascular T1 and T2 * effects well after the contrast agent initial bolus has passed through tissue. By separating and quantifying these T1 and T2 * effects in the period of time after the contrast agent’s first pass we propose that a new metric, termed the extravascular susceptibility calibration factor (Ke), can be derived and used to assess cellular packing heterogeneity. In this study we demonstrate that Ke may be used to differentiate between tumor types with varying cellular features.

 
1527.   Limitation of DCE-MRI in Xenograft Model Study
Septian Hartono1, Tong San Koh2, Quan Sing Ng2, Richard Ong2, Hung The Huynh2, Sidney Yu3, Sotirios Bisdas4, Laurent Martarello5, and Choon Hua Thng2
1Nanyang Technological University, Singapore, Singapore, 2National Cancer Centre, Singapore, Singapore, 3Singapore General Hospital, Singapore, 4Eberhard Karls University, Tübingen, Germany, 5F. Hoffmann-La Roche, Switzerland

 
DCE-MRI has been used extensively in preclinical and clinical trials as a biomarker of drug effect. It is commonly assumed that a decrease in blood volume and blood flow is related to drug effect. This study examines the pitfall of such an assumption and illustrates decrease in perfused blood volume in untreated tumor as derived by DCE-MRI

 
1528.   Delayed bolus arrival time with high molecular weight contrast agent, an indicator of necrosis
Kelly C McPhee1, Jennifer HE Baker1,2, Katayoun Saatchi3, Urs O Häfeli3, and Stefan A Reinsberg1
1Physics and Astronomy, University of British Columbia, Vancouver, BC, Canada, 2Radiation Biology Unit, BC Cancer Research Centre, Vancouver, BC, Canada, 3Faculty of Pharmaceutical Sciences, University of British Columbia, Vancouver, BC, Canada

 
The bolus arrival time (BAT) is the time at which signal enhancement commences, following the injection of a contrast agent. Two MRI studies were performed one day apart, the first using Bayer Healthcare’s Gadovist, and the second with a high-molecular-weight contrast agent, Hyperbranched polyglycerol (HPG) derivatized with p-NH2-benzyl-DOTA. The BAT maps for the same tumour are compared to corresponding whole tumour histology sections showing necrotic and healthy tissue. Areas where BAT is delayed relative to surrounding tissue match necrotic areas in histology, with longer delays in the BAT of HPG-Gd than Gadovist. Thus, BAT is not only an important input parameter for pharmacokinetic modelling, but also a reproducible, phenomenological parameter in its own right.

 
1529.   A Six-Fold Throughput Improvement For Preclinical Cancer Studies
Marc S Ramirez1, Yunyun Chen2, Stephen Y Lai2, and James A Bankson1
1Imaging Physics, The University of Texas M.D. Anderson Cancer Center, Houston, TX, United States, 2Head & Neck Surgery, The University of Texas M.D. Anderson Cancer Center, Houston, TX, United States

 
To promote the use of MRI for preclinical evaluation of experimental cancer therapies, cost should be reduced, scanner access should increase, and more animals should be scanned near a common longitudinal time point. A 20-coil array system permits a combination of multi-animal and parallel imaging accelerations to substantially improve the throughput of a preclinical DCE-MRI study of a thyroid tumor model compared to that which can be achieved with a commercially-available single-mouse hardware setup. A comparison of throughput, image quality, and consistency of resulting pharmacokinetic parameters are described. Furthermore, the logistics of simultaneously preparing and monitoring five animals are discussed.

 
1530.   Dynamic Contrast Enhanced MRI at 7T in a Rat Model of Cerebral Glioma: Data Analysis and Model Selection
James Russell Ewing1, Madhava Aryal2, Hassan Farhad Bagher-Ebadian1, Swayamprava Panda3, Kishor Karki1, Nagaraja Tavarekere4, Glauber Cabral5, Joseph Fenstermacher4, and Tom Mikkelsen1
1Neurology, Henry Ford Hospital, Detroit, Michigan, United States, 2Physics, Oakland University, Rochester Hills, Michigan, United States, 3Neurology, Henry Ford Hospital, Detroit, United States, 4Anesthesiology, Henry Ford Hospital, Detroit, Michigan, United States, 5Neurology, Henry Ford Hospital, Detroit, m, United States

 
In DCE studies in a rat model of cerebral glioma, test-retest variability is examined when a Model Selection paradigm is employed

 
1531.   Investigating the Repeatability of Quantitative DCE-MRI in Mice
Stephanie L. Barnes1,2, Jennifer G. Whisenant2,3, Gregory D. Ayers4, and Thomas E. Yankeelov1,2
1Radiology and Radiological Sciences, Vanderbilt University, Nashville, TN, United States, 2Institute of Imaging Sciences, Vanderbilt University, Nashville, TN, United States,3Chemical and Physical Biology, Vanderbilt University, Nashville, TN, United States, 4Cancer Biostatistics, Vanderbilt University, Nashville, TN, United States

 
MRI techniques have been developed that have the potential to evaluate the response of tumors to treatment in a more sensitive manner than physical change in tumor size. However, confident implementation of these methods for tumor evaluation requires knowledge of their repeatability. The focus of this work is the evaluation of the repeatability of DCE-MRI in mice. Both 1282 and 642 acquisition matrices were evaluated, with 642 consistently demonstrating higher repeatability. Specifically in the 642 case, a statistically significant change in Ktrans and ve for a group of 12 mice is 7.3% and 3.9%, respectively.

 
1532.   A quantitative MRI multi-parametric assay of colorectal cancer in APC Δ468 mice
Zhuoli Zhang1, Weiguo Li1, Nichole R Blatner2, Kristen Dennis2, Daniele Procissi1, Khashayarsha Khazaie2,3, and Andrew C Larson1,4
1Radiology, Northwestern University, Chicago, IL, United States, 2Medicine, Northwestern University, Chicago, IL, United States, 3R. Lurie Comprehensive Cancer Center, Northwestern University, Chicago, IL, United States, 4Biomedical Engineering, Northwestern University, Evanston, IL, United States

 
The mouse model of hereditary intestinal cancer based on haploinsufficiency of the adenomatous polyposis coli gene (APCΔ468) has been widely validated for studying the pathophysiology and carcinogenesis of human disease in pre-clinical research settings. By providing a organ specific (colon) tumor it offers the opportunity to test new therapies and observe tumor progression and response in a “realistic” tissue microenvironment. In this study, we investigated the ability to use MR techniques to 1) rapidly and reliably detect colorectal tumors in the transgenic APCΔ468 mouse model and 2) identify tumor-specific and potentially therapeutically relevant imaging biomarkers.
 
Traditional Poster Session - Cancer

Cancer Models - Therapy Response
Click on to view the abstract pdf. Click on to view the poster (Not all posters are available for viewing.)
 
Wednesday 9 May 2012
Exhibition Hall  10:00 - 12:00

1533.   The functional diffusion map provides early prediction of recurrence in a glioma model following radiotherapy
Benjamin Lemasson1, Stefanie Galbán2, Fei Li1, Kevin Heist1, Alnawaz Rehemtulla1,2, Craig Galbán1, and Brian Ross1
1Radiology, University of Michigan, Ann Arbor, Michigan, United States, 2Radiation Oncology, University of Michigan, Ann Arbor, Michigan, United States

 
The goal of this study was to evaluate the functional diffusion map (fDM) as a biomarker of tumor recurrence on an animal-by-animal basis following different doses of radiation (1G, 2G and 4G) on a genetically engineered murine GBM model. Tumor size and fDM were monitor daily for a week and then every two days. We observed a large inter- and intra-group variability of time-to-recurrence. The maximum fDMrADC+ values measured during radiation therapy was correlated strongly to time-to-recurrence (R2=0.85). fDMrADC+ technique may serve as a biomarker of tumor recurrence that is insensitive to the response heterogeneity typically observed in GBM.

 
1534.   Assessing XL184 treatment in metastatic prostate cancer to the bone by diffusion mri
Jean-Christophe Brisset1, Benjamin A Hoff1, Stefanie Galbán2, Benjamin Lemasson1, Alnawaz Rehemtulla2, Craig J Galbán1, and Brian D Ross1
1Department of Radiology, University of Michigan, Ann Arbor, Michigan, United States, 2Department of Oncology, University of Michigan, Ann Arbor, Michigan, United States

 
Molecularly targeted therapies are seen as alternatives to chemotherapy in treating cancer. Although promising, typical volumetric based approaches for response assessment prove inadequate for targeted agents. This study aims to determine the effectiveness of DW-MRI at assessing response to an oral kinase inhibitor, Cabozantinib, after one week of treatment in a prostate bone metastasis model. We observed a significant increase in tumor ADC values following treatment by Cabozantinib, which correlated with the reduction in tumor growth rate. These results demonstrate the potential of quantitative ADC maps for assessing tumor response early following treatment completion.

 
1535.   Differential response to radiotherapy in a mouse xenograft model with half-field irradiation detected by combined DCE and BOLD MRI
Yu-Chun Lin1,2, Chun-Chieh Wang3, Yi-Ping Lin3, Yun-Han Lin4, and Jiun-Jie Wang5
1Department of Diagnostic Radiology, Chang Gung Memorial Hospital, Linkou, Taiwan, Taiwan, 2Department of Electrical Engineering, Chang Gung University, Taoyuan, Taiwan, Taiwan, 3Department of Radiation Oncology, Chang Gung Memorial Hospital, 4Molecular Imaging Center, Chung Gung Memorial Hospital, 5Department of Medical Imaging and Radiological Sciences, Chang Gung University

 
Transgenic adenocarcinoma of the mouse prostate (TRAMP)-C1 tumors were irradiated on half of the tumor. Treatment response was assessed by using DCE and BOLD MRI on the 6th day after radiotherapy. Results showed that the Giant cell formed on the irradiated portion of the tumor. The irradiated area showed increased Ktrans and reduced BOLD response to carbogen breathing as compared with those at non-irradiated area. The reduced BOLD response to carbogen is related to the decreased microvascular density, which was evidenced by immunohistochemistry.

 
1536.   A Spatially Resolved Evaluation of Radiation Induced Metabolic Response in Normal and Malignant Liver with 3D 31P MRSI
Scott Jones1,2, Anshuman Panda1,2, Higinia Cardenes3, James Fletcher2, Gary Hutchins2, 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, IN, United States, 3Department of Radiation Oncology, Indiana University School of Medicine, Indianapolis, IN, United States

 
The purpose of this study is to evaluate the diagnostic and/or prognostic value of 3D 31P MRSI to assess a spatially resolved early metabolic response to ionizing radiation in both healthy and malignant liver tissue. A 3D 31P MRSI protocol using a dual-tuned 1H/31P 8-channel phased array liver coil was used to obtain 31P metabolic information throughout the whole human liver at 3.0T. 31P MRSI data from patients with hepatocellular cancer acquired before and 24 hours after undergoing stereotactic body radiotherapy are presented and show clear differential metabolic responses to radiation between healthy and malignant tissue.

 
1537.   Identification of High Intensity Focused Ultrasound treated tumor tissue using a multiparametric MRI protocol and ISODATA analysis
Stefanie J.C.G. Hectors1, Igor Jacobs1, Gustav J. Strijkers1, and Klaas Nicolay1
1Biomedical NMR, Department of Biomedical Engineering, Eindhoven University of Technology, Eindhoven, Netherlands

 
To advance the clinical application of HIFU treatment of malignant tumors, a time-efficient multislice multiparametric MRI protocol, consisting of quantification of T1, T2, ADC and MTR, was developed. Image clustering techniques were used to differentiate non-treated and HIFU-treated tumor tissue. Results showed that after HIFU ablation, a region emerged in which pixels were assigned to clusters identified as HIFU-treated tumor tissue. MRI parameter values in this region were significantly different from parameter values in tissue identified as non-treated tumor tissue. Furthermore, a strong correlation was observed between MRI-derived HIFU-treated tumor tissue fractions and histologically derived non-viable tumor tissue fractions.

 
1538.   False-Negative MRI Biomarkers of Tumour Response to Targeted Cancer Therapeutics
Jessica K.R. Boult1, Yann Jamin1, Vivien Jacobs2, Lesley D. Gilmour1, Simon Walker-Samuel1, Jane Halliday2, Paul Elvin2, Anderson J. Ryan2, John C. Waterton2, and Simon P. Robinson1
1CRUK and EPSRC Cancer Imaging Centre, Division of Radiotherapy and Imaging, The Institute of Cancer Research and Royal Marsden NHS Foundation Trust, Sutton, Surrey, United Kingdom, 2AstraZeneca, Alderley Park, Cheshire, United Kingdom

 
The use of pharmacodynamic biomarkers, including imaging biomarkers, is now desirable for the evaluation of novel molecularly targeted therapeutics in oncology. Before their deployment in clinical trials, such imaging biomarkers require evaluation. Here we describe two preclinical studies in which emerging MRI biomarkers were correlated with histology to assess tumour response to Src kinase or VEGFR2 inhibition. In both studies, treatment resulted in pathological target inhibition, but the corresponding imaging biomarkers failed to show the anticipated change. Reporting of such negative preclinical imaging biomarker responses is informative for clinical trial design.

 
1539.   Dose-dependent effects of Bevacizumab in human HCC xenografts
Septian Hartono1,2, Tong San Koh1,2, Quan Sing Ng2, Richard Ong2, Hung The Huynh2, Sidney Yu3, Sotirios Bisdas4, Laurent Martarello5, and Choon Hua Thng2
1Nanyang Technological University, Singapore, Singapore, 2National Cancer Centre, Singapore, Singapore, 3Singapore General Hospital, Singapore, 4Eberhard Karls University, Tübingen, Germany, 5F. Hoffmann-La Roche, Switzerland

 
We aim to determine if DCE MRI is a sensitive enough technique to detect changes in fractional intravascular volume and blood flow after administration of a single dose of bevacizumab. The results showed that the effects of bevacizumab are dose-related. A more gradual drop of blood volume was observed in group treated with bevacizumab 1mg/kg. On the other hand, a steep drop of blood volume was observed in group treated with bevacizumab 10mg/kg. The results suggested potential of DCE MRI as a sensitive biomarker of microvascular density.

 
1540.   Evaluation of Anticancer-drug Efficacy in Tumor-bearing Rat by Using 19F/1H-MRI
Yosuke Otake1, Koji Hirata1, Yoshihisa Soutome1, and Yoshitaka Bito1
1Hitachi, Ltd., Central Research Laboratory, Kokubunji, Tokyo, Japan

 
A method for evaluating efficacy of 19F-containing drugs on the basis of an image of active metabolites obtained by 19F-MRI and a k-means class map of tumor status obtained by 1H-MRI was developed. This method was used to evaluate the drug efficacy of a 5-FU in a tumor-bearing rat. The obtained image of active metabolites and the k-means map of the rat were evaluated by using binary classification. The binary-classification result shows the regions of positive effect and negative effect of the 5-FU in the rat. The developed method will therefore be a powerful tool for pharmacokinetics and pharmacodynamics research.

 
1541.   Regression of Glioma Tumor Growth in a F98 Rat Glioma Model by the Nitrone, OKN-007
Rheal A. Towner1, David L. Gillespie2, Debra Saunders1, Osama Abdullah3, Edward W. Hsu4, Andrea Schwager5, and Randy L. Jensen2
1Advanced Magnetic Resonance Center, Oklahoma Medical Research Foundation, Oklahoma City, OK, United States, 2Huntsman Cancer Institute, University of Utah, Salt Lake City, UT, United States, 3Bioengineering, University of Utah, Salt Lake City, UT, 4Bioengineering, University of Utah, Salt Lake City, UT, United States, 5Interdepartmental Program in Neuroscience, University of Utah, Salt Lake City, UT, United States

 
Magnetic resonance imaging and spectroscopy was used to follow the regression of rat F98 gliomas following treatment with the nitrone compound, OKN-007. Following MR and bioluminescence image detection of F98 gliomas, OKN-007 (administered orally) was found to decrease tumor growth. MR spectroscopy analysis (metabolite/tCr (total creatine) peak area ratios, and LCModel) indicated F98 glioma-induced alterations in tumor metabolites (tCho (total choline), tCr, NAA (N-acetyl aspartate), Lip1.3 (methylene hydrogens in lipid acyl groups), Lip5.3 (olefinic hydrogens in unsaturated lipid acyl groups)), were found to revert back to normal levels following OKN-007 treatment. OKN-007 may be considered as a promising therapeutic addition or alternative for the treatment of human gliomas.

 
1542.   NMR Metabolomic and LIBS elemental profiling of anticancer herbal formulation
Rama Jayasundar1, Gaurav Sharma1, Shyam S Chauhan2, and Thirumurty Velpandian3
1Department of NMR and MRI, All India Institute of Medical Sciences, New Delhi, India, 2Department of Biochemistry, All India Institute of Medical Sciences, New Delhi, India,3Department of Occular Pharmacology, All India Institute of Medical Sciences, New Delhi, Delhi, India

 
The study evaluated the metabolic profiling, elemental analysis and anticancer potential on four polyherbal formulations namely KG, VK, MK and GTK using NMR, LIBS and MTT assay, respectively. Antioxident potential of formulations was carried out using FRAP assay. Amongst four formulations maximum cytotoxicity was observed for KG (IC50 22.48 lower case Greek mug/ml)followed by MK (IC50 27.58 lower case Greek mug/ml). Using FRAP assay maximum antioxidant potential was achieved for VK (17.0 lower case Greek muM Fe++g-1) amongst four. KG and MK formulations were selected for characterization through NMR Spectroscopy, which revealed the chemical indentification of metabolites to explore pharmacological action. LIBS data supports antioxident properties of formulations.

 
1543.   Combined Look-Locker arterial spin labeling (ASL) and intrinsic R2*susceptibility response to vascular disruption in a clinically relevant liver metastatic model of colorectal carcinoma
Sean Peter Johnson1, Rajiv Ramasawmy2, Adrienne Campbell2, Mathew Robson1, Mario Mazzantini1, Vineeth Rajkumar1, Barbara Pedley1, Mark Lythgoe2, and Simon Walker-Samuel2
1Cancer Institute, UCL, London, United Kingdom, 2Centre for Advanced Biomedical Imaging, UCL, London, United Kingdom

 
Liver metastases are the major cause of mortality in patients with colorectal carcinoma (CRC). The vascular disrupting agent OXi4503 has been tested in phase I clinical trials of metastatic disease with R2* recommended as a biomarker of response. R2* response however may not accurately reflect response to treatment exclusively. Arterial spin labeling (ASL) is able to assess changes in tumour perfusion. We show that in a clinically relevant liver metastatic model of CRC (n=10 metastases) acquisition of combined R2* and ASL at baseline and 90min following 40mg/kg OXi4503 i.v. is more adequate at assessing response to treatment.
 
Traditional Poster Session - Cancer

Cancer - Cells
Click on to view the abstract pdf. Click on to view the poster (Not all posters are available for viewing.)
 
Wednesday 9 May 2012
Exhibition Hall  10:00 - 12:00

1544.   Chemical Exchange Saturation Transfer (CEST)-MRI detects free choline in breast cancer cells
Jannie P Wijnen*1,2, Kannie WY Chan*1,3, Peter CM van Zijl1,4, Michael T McMahon**1,4, and Kristine Glunde**1
1Russell H. Morgan Department of Radiology and Radiological Sciences, Johns Hopkins University School of Medicine, Baltimore, MD, United States, 2Department of Radiology, University Medical Centre Utrecht, Utrecht, Netherlands, 3Cellular Imaging Section and Vascular Biology Program, Institute for Cell Engineering, Baltimore, MD, United States,4F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, MD, United States

 
Magnetic Resonance Spectroscopy (MRS) detects high levels of total choline-containing metabolites (tCho) in malignant cancers, which is important for cancer diagnosis and therapy. 1H MRS measures the tCho levels, but cannot resolve the overlapping signals of free choline (Cho), PC, and GPC that the tCho signal consists of. To develop novel imaging approaches with high molecular specificity, we have explored Chemical Exchange Saturation Transfer (CEST) to monitor exchangeable protons of phospholipid metabolites. The CEST contrast at 1.2 ppm correlated with the Cho level measured by high-resolution MRS in cell extracts, and could be used to assess malignancy in breast cancers. *Authors contributed equally ** Authors share the corresponding authorship

 
1545.   siRNA-mediated silencing of the glycerophosphocholine phosphodiesterase GDPD5 in breast cancer cells
Maria Dung Cao1, Lu Jiang2, Tiffany R. Greenwood2, Balaji Krishnamachary2, Zaver M. Bhujwalla2, Ingrid S. Gribbestad1, and Kristine Glunde2
1Department of Circulation and Medical Imaging, Norwegian University of Science and Technology (NTNU), Trondheim, Norway, 2Russell H. Morgan Department of Radiology and Radiological Sciences, The Johns Hopkins University School of Medicine, Baltimore, Maryland, United States

 
We previously demonstrated that the glycerophosphocholine phosphodiesterase (GPC-PDE) encoded by GDPD5 is partially responsible for the relatively low glycerophosphocholine (GPC) levels in human breast tumor samples, and that it is associated with cancer malignancy. Here we transiently silenced GDPD5 in human breast cancer cells using siRNA. Magnetic resonance spectroscopy revealed increased GPC levels following GDPD5 silencing, suggesting that GDPD5 catalyzes the degradation of GPC in human breast cancer cells. Total choline and phosphocholine levels increased in highly malignant MDA-MB-231 cells, but not in weakly malignant MCF-7 cells upon GDPD5 silencing, indicating different roles of GDPD5 in these two cell lines.

 
1546.   Lentiviral choline kinase shRNA transduction of cells and tumors in vivo regulates breast cancer stem cell markers CD44 and ABCG2
Balaji Krishnamachary1, Marie-France Penet1, Mayur M Gadiya1, Noriko Mori1, Yelena Mironchik1, kristine glunde1, and Zaver M Bhujwalla1
1Radiology, JHU ICMIC Program, The Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University, Baltimore, Maryland, United States

 
Synopsis: Stem-like breast cancer cells (SBCCs) are drug resistant, invasive, and likely to lead to recurrence and repopulation. High CD44 adhesion molecule expression and high expression of the drug transporter ABCG2 are two markers associated with populations enriched with SBCCs. Altered choline metabolism is one of the hallmarks of cancer. Cancers typically exhibit elevated phosphocholine mostly due to increased choline kinase expression and activity. Here we have examined the relationship between choline kinase and these two markers of SBCCs. Downregulating choline kinase expression resulted in decreased CD44 and ABCG2. These studies provide insight into potential metabolic targeting of SBCCs.
 
Traditional Poster Session - Cancer

Cancer - Others
Click on to view the abstract pdf. Click on to view the poster (Not all posters are available for viewing.)
 
Wednesday 9 May 2012
Exhibition Hall  10:00 - 12:00

1547.   The Utility of 3D DCE-MRI for Assessing Treatment Response in Oesophageal Cancer
Caleb Roberts1, Geoff J Parker1, Ahmad Mirza2, Andrew Jackson3, Yvonne Watson1, Susan Cheung1, Giovanni Buonaccorsi1, and Josephine H Naish1
1Biomedical Imaging Institute, The University of Manchester, Manchester, Greater Manchester, United Kingdom, 2Departments of Gastrointestinal Surgery and Histopathology, University Hospital of South Manchester, Manchester, Greater Manchester, United Kingdom, 3Clinical Oncology, University Hospitals Southampton NHS Foundation Trust, Southampton, Hampshire, United Kingdom

 
There is a need to develop imaging methods that can assess treatment response and help individualise therapy in patients with oesophageal cancer. We explore the utility of dynamic contrast-enhanced MRI in a pilot study of 5 patients with oesophageal cancer. Each patient underwent two 3D DCE-MRI scans, each separated by a course of radical chemo radiotherapy. All patients showed significant treatment response demonstrated by changes in post-treatment pharmacokinetic parameters. We have successfully applied 3D DCE-MRI in oesophageal cancer and demonstrated its potential to assess treatment response.

 
1548.   Improving the accuracy of DCE-MRI-based prediction of bevacizumab- and FOLFOX6-induced CRC liver metastasis shrinkage
Saada A M Abujarada1,2, James P B O'Connor1,3, and Chris J Rose1,2
1University of Manchester Biomedical Imaging Institute, Manchester, Greater Manchester, United Kingdom, 2University of Manchester Academic Health Science Centre, Manchester, Greater Manchester, United Kingdom, 3Department of Radiology, Christie Hospital NHS Trust, Manchester, Greater Manchester, United Kingdom

 
MRI-derived biomarkers, measured before treatment, may predict tumor response. Such research tends to use linear regression that may overlook differences in biomarker reliability (interscan repeatability). Where reliability is considered, it is often quantified separately to the regression task, rather than within the same conceptual framework. We describe a novel nonlinear model that explicitly models biomarker reliability and compare its predictions to those from a linear errors-in-variables model in a study of liver metastases treated with bevacizumab and FOLFOX6. While the median prediction error of the methods is equal, our method makes substantially fewer large errors.

 
1549.   Multi-modality imaging in the prediction of response to systemic treatment in colorectal cancer: Preliminary results
E.G.W. ter Voert1, L. Heijmen2, C.J.A. Punt2, A. Heerschap1, and H.W.M. van Laarhoven2
1Radiology, Radboud University Nijmegen Medical Centre, Nijmegen, Gelderland, Netherlands, 2Medical Oncology, Radboud University Nijmegen Medical Centre, Nijmegen, Gelderland, Netherlands

 
Fifty percent of the patients with colorectal cancer develop distant metastases, mainly in the liver. Early response monitoring is desirable as only a subset of patients responds to the potentially toxic and expensive systemic treatment. The aim of this study is to predict response to systemic treatment in patients with colorectal liver metastases using pre-treatment measurements of the apparent diffusion coefficient (ADC) and the T2*. The preliminary results indicate, after analyzing 79 lesions in 25 patients, that high pre-treatment ADC values and possibly low pre-treatment T2* values in tumor tissue predict good treatment outcome.

 
1550.   ACCURACY OF MRI IN PREDICTION OF TRANSMURAL INVASION AND TUMOUR-FREE RESECTION MARGIN IN RECTAL CANCER
Peter Brotchie1,2, and Shalini Amukotuwa1
1MRI, Geelong Hospital, Geelong, Victoria, Australia, 2Radiology, University of Melbourne, Melbourne, Victoria, Australia

 
Local recurrence is a major obstacle in curative surgery for rectal carcinoma. The main factor affecting local recurrence is tumour involvement of the circumferential resection margin (CRM). If CRM is involved a long-course of chemoradiotherapy is given to reduce local recurrence rates. If not, a short-course of neoadjuvant radiotherapy decreases local recurrence in patients with transmural invasion of tumour. For these reasons, accurate pre-operative identification of transmural invasion and CRM involvement is needed. Rectal MRIs were performed on 101 consecutive patients with histologically proven rectal adenocarcinoma. Histopathologically, transmural invasion (T3 or T4) was present in 29 of 51 (T1 or T2) tumours and absent in 22 of 51. 25 of the 29 tumours with transmural invasion were correctly identified with 4 false negatives. 19 of the 22 tumours without transmural invasion were correctly identified with 3 false positives (Accuracy: 86%, Sens: 86%, Spec: 86 %, PPV: 89%, NPV: 83 %). Histopathologically CRM was involved in 7 of 48 tumours and not involved in 41 of 48 tumours. With MRI, CRM involvement was correctly identified in 7 of 7 cases and correctly identified as absent in 37 with 4 false positives (Sens 100%, Spec 90%, PPV 64%, NPV 100%).
 
Traditional Poster Session - Cancer

Cancer Models - Metabolism & Spectroscopy
Click on to view the abstract pdf. Click on to view the poster (Not all posters are available for viewing.)
 
Wednesday 9 May 2012
Exhibition Hall  10:00 - 12:00

1552.   Metabolic Imaging of Hepatocellular Carcinoma in HBsAg transgenic Mouse Model Treated With Aflatoxin B1: a New Biomarker
Jadegoud Yaligar1, Wei W Teoh2, Swee Shean Lee1, Kanaga Sabapathy2, Philip William Kuchel1, and S. Sendhil Velan1
1Laboratory of Molecular Imaging, Singapore Bioimaging Consortium, Singapore, Singapore, Singapore, 2Laboratory of Molecular Carcinogenesis, National Cancer Center, Sinapore, Singapore, Singapore

 
Aflatoxin-B1 and hepatitis-B virus are the most common etiological factors associated with high incidence of hepatocellular carcinoma (HCC) in Asia. Epidemiological studies have also suggested a strong correlation between AFB1 exposure and a signature mutation on the tumor suppressor gene, p53. We have investigated the HCC model that closely mimics human HCC, induced by expression of the Hepatitis surface antigen as a transgene from the albumin promoter (HBsAg) after treatment with AFB. We performed in vivo MRI/MRS and in-vitro MAS experiments and analyzed longitudinal changes of diffusion and tissue biochemistry. We detected carnitine for the first time, to our knowledge, in HCC tumors of HBsAg mice. Therefore relatively high concentrations of carnitine may be a biomarker for the early detection of HCC.

 
1553.   MRI and Spectroscopy for Characterization of Primary Human Mutant IDH1 (IDH1-R132H) Glioblastoma Xenografts
Yanping Sun1, Shakti Ramkissoon2, Matthew A Theisen2, Amy S Freund3, Kristen L Jones1, Marika Hayashi2, Juan Wang1, Keith Ligon2, and Andrew L Kung1,4
1Lurie Family Imaging Center, Dana-Farber Cancer Institute, Boston, MA, United States, 2Center for Molecular Oncologic Pathology, Dana-Farber Cancer Institute, 3Bruker BioSpin Corp., Billerica, 4Pediatric Oncology, Children’s Hospital, Boston

 
Mutations in isocitrate dehydrogenase (IDH1/2) and excessive production of the 2-hydroxyglutarate (2HG) have been found in low grade gliomas and secondary glioblastomas (GBMs). In this study, we developed an intracranial xenograft GBM model harboring the IDH1-R132H mutation. MRI showed that T1 and T2 in tumor were higher, while tumor perfusion was lower, than normal tissue. 1D and 2D MRS demonstrated the presence of 2HG in IDH tumor but absent in control tumor. The tumor was characterized as a densely cellular glial neoplasm composed of large pleomorphic cells, which were positive by immunohistochemistry for the mutant form of IDH1

 
1554.   Glioma cells overexpressing isocitrate dehydrogenase 1 (IDH1) mutation produce 2-hydroxy glutaric acid detectable in vivo
Jelena Lazovic1, Horacio Soto2, David Piccioni2, Arthur Chou2, Sichen Li2, Robert Prins2, Linda Liau2, Timothy Cloughesy2, Albert Lai2, and Whitney Pope3
1Radiology, University of California, Los Angeles, CA, United States, 2University of California, 3Radiology, University of California, Los Angeles

 
The presence of isocitrate dehydrogenase 1 (IDH1) R132 mutation in gliomas including secondary glioblastoma is associated with more favorable outcome and increased overall survival compared to patients with functional IDH1. The aim of this study was to investigate metabolic changes and tumor growth rates in U87 glioma cells transformed to express mutated IDH1-R132. We found IDH1-R132 overexpression to be associated with an increase in tumor growth rate. Metabolic changes associated with the IDH1-R132 mutation included elevated levels of 2-hydroxyglutaric acid and reduced glutamate levels.

 
1555.   Compartmental modelling of regional tumour glucose pharmacokinetics with quantitative glucoseCEST
Simon Walker-Samuel1, Rajiv Ramasawmy1, Francisco Torrealdea2, Marilena Rega2, Peter Johnson3, Vineeth Rajkumar3, Simon Richardson1, Dave Thomas2, Barbara Pedley3, Xavier Golay2, and Mark F. Lythgoe1
1Centre for Advanced Biomedical Imaging, University College London, London, United Kingdom, 2Institute of Neurology, University College London, United Kingdom, 3Cancer Institute, University College London, United Kingdom

 
GlucoseCEST has been shown to allow the detection of exogenously administered, unlabelled glucose in tumours and we have recently extended this technique to quantify glucose concentration in vivo. In turn, this has enabled us to perform pharmacokinetic modelling of regional tumour glucose uptake. This provided estimates of the rate of glucose extravasation from blood plasma and the fractional volume accessible to glucose, using blood plasma glucose measurements from direct blood sampling. The current study is a proof-of-principle demonstration and the results open the possibility for applying more complex multi-compartmental analysis to measure regional tumour glucose metabolism.