ISMRM 23rd Annual Meeting & Exhibition • 30 May - 05 June 2015 • Toronto, Ontario, Canada

Electronic Poster Session • Cancer
3810 -3821 Cancer: Preclinical Studies of Animal Models
3822 -3824 Cancer: Clinical & Preclinical Studies on New Contrast Mechanisms
3825 -3833 Breast Cancer: Technical
3834 -3855 Cancer: Prostate Cancer
3856 -3870 Tumor Therapy Responses: Preclinical & Clinical (except Brain Tumor)
3871 -3871 Cancer: Other, Original Research
3872 -3876 Tumor Perfusion & Permeability Applications
3877 -3878 Cancer: Other Cancers
3879 -3893 Breast Cancer Clinical
3894 -3898 Cancer: Others

Note: The videos below are only the slides from each presentation. They do not have audio.


Tuesday 2 June 2015
Exhibition Hall 16:00 - 17:00

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3810.   1 Radiation induced hypoxia in TRAMP tumor detected using BOLD MRI - permission withheld
Yu-Chun Lin1, Gigin Lin1, Chun-Chieh Wang2, and Jiun-Jie Wang3
1Department of Diagnostic Radiology, Chang Gung Memorial Hospital, Linkou, Taiwan, Taiwan, 2Department of Radiation Oncology, Chang Gung Memorial Hospital, Linkou, Taiwan, 3Department of Medical Imaging and Radiological Sciences, Chang Gung University, Yaoyuan, Taiwan

This study monitored the changes of microvasculature and hypoxia after radiotherapy in TRAMP tumor using carbogen challenging BOLD MRI. A single dose irradiation was delivered in peripheral half of the tumor. The BOLD response to carbogen in the irradiated portion decreased compared with the non-irradiated portion. The immunohistochemistry images of CD31 and pimonidazole showed less hypoxia in the irradiated portion, while a trend of acute hypoxia in the non-irradiated region was noticed to shift to chronic hypoxia in the irradiated region. Carbogen-challenging BOLD MRI can be used to detect the hypoxic change within a tumor in response to radiotherapy

3811.   2 Biomarkers of Aggressive Breast Cancer Revealed by Combining Magnetic Resonance Spectroscopic Imaging and Mass Spectrometric Imaging - permission withheld
Lu Jiang1, Kamila Chughtai2, Tiffany Greenwood1, Zaver M. Bhujwalla1, Venu Raman1, Gert Eijkel2, Ron Heeren2, and Kristine Glunde1
1Department of Radiology, Johns Hopkins University School of Medic, BALTIMORE, MD, United States, 2FOM-Institute AMOLF, Amsterdam, Netherlands

The total choline (tCho) signal in magnetic resonance spectroscopic imaging (MRSI) of tumors is a potential biomarker of breast cancer aggressiveness and can be visualized in vivo by H1 MRSI tCho maps. Mass spectrometry imaging (MSI) of histologic tumor sections is able to detect thousands of biomolecules, including tryptic peptides from on-tissue digested proteins, from the tissue surface. We have investigated differentially regulated proteins in high- versus low-tCho regions in a human breast cancer model by combining in vivo MRSI with ex vivo MSI, which identified specific protein species that are spatially correlated with tCho.

3812.   3 In vivo Lactate T1 and T2 Relaxation Times in Preclinical Cancer Models – Absolute Quantification of Tumor Lactate
Ellen Ackerstaff1, H. Carl LeKaye1, Natalia Kruchevsky1, Kristen L. Zakian1, Nirilanto Ramamonjisoa1, Ekaterina Moroz1, Inna S. Serganova1, Ronald G. Blasberg1, and Jason A. Koutcher1
1Memorial Sloan Kettering Cancer Center, New York, NY, United States

Increased lactate has been associated with aggressive, treatment-resistant tumors. To quantify in vivo lactate from MR spectra acquired using lactate-editing, knowing in vivo lactate T1 and T2 relaxation times is essential. Preclinically, accurate in vivo T1 and T2 values are difficult to obtain and few are reported. We aim to fill this void. We found similar T1 and T2 values for two prostate cancer models, which were lower than previously reported values in other cancers. We now expand our studies to include more tumor models for our future research studying the role of lactate in tumor development, progression, and treatment response.

3813.   4 Comparison of APT- and NOE-CEST in rat glioma at 7 T– Potentials for tumor characterization and detection of tumor cell infiltration
Mona Salehi Ravesh1, Monika Huhndorf2, Amir Moussavi1, Kristin Koetz1, Judith Becker1, Kirsten Hattermann3, and Susann Boretius1
1Clinic of Radiology and Neuroradiology, Section Biomedical Imaging, Kiel, Schleswig-Holstein, Germany, 2Department of Radiology and Neuroradiology, Schleswig-Holstein, Germany, 3Christian-Albrechts-University of Kiel, Anatomical Institute, Schleswig-Holstein, Germany

Amide proton transfer (APT) and the Nuclear Overhauser Enhancement (NOE) have emerged as potential new imaging contrasts. Here we applied these techniques on a glioma model in rats. Maps of the magnetization transfer rate, both at -3.5 ppm and +3.5 ppm, revealed a reduction of the MTR in the tumor. NOE-CEST however revealed additional information about the tumor boundaries. Thus, NOE-CEST MRI may confer specific benefits in the detection and characterization of glioblastoma in patients.

3814.   5 cPLA2IVA inhibition in basal-like breast cancer: Reduced tumor growth with metabolic, vascular and gene expression changes
Hanna Maja Tunset1, Eugene Kim1, Jana Cebulla1, Muhammad Riyas Vettukattil1, Astrid Jullumstrř Feuerherm2, Berit Johansen 2, Tone Frost Bathen1, and Siver Andreas Moestue1
1MR Cancer Group, Department of Circulation and Medical Imaging, Norwegian University of Science and Technology, Trondheim, Norway, 2Avexxin AS, Department of Biology, Norwegian University of Science and Technology, Trondheim, Norway

The cPLA2IVA gene PLA2G4A is highly expressed in aggressive basal-like breast cancer (BLBC) and may be represent a new therapeutic target. 1H HR MAS MRS, µCT, and gene expression analysis were used to explore the effect of cPLA2IVA inhibition in BLBC xenografts. Treatment significantly inhibited tumor growth and induced early favorable metabolic changes (higher PCho, lower GPC), intermediate anti-angiogenic effects (smaller vessels, avascular regions), and late gene expression changes (up-regulated transcription and translation, possibly apoptosis). Thus, cPLA2IVA inhibition may represent a novel strategy for targeted treatment of BLBC

3815.   6 Spectroscopic imaging with hyperpolarized [1-13C]pyruvate shows an elevated lactate/pyruvate ratio in contrast enhancing and non-enhancing brain tumors of orthotopic patient-derived xenograft models of glioblastoma.
Richard Mair1,2, Alan Wright1, Kieren Allinson3, Tiago Rodrigues1, Colin Watts2, and Kevin Brindle1
1CRUK Cambridge Institute, University of Cambridge, Cambridge, Cambridgeshire, United Kingdom, 2Division of Neurosurgery, University of Cambridge, Cambridge, Cambridgeshire, United Kingdom, 3Department of Pathology, Cambridge University Hospitals NHS Foundation Trust, Cambridgeshire, United Kingdom

Glioblastoma is the most common human-primary-intracranial neoplasm and has the worst prognosis. Novel orthotopic patient-derived xenograft models that recapitulate the pathophysiological phenotype of the disease allow development of novel imaging modalities for downstream clinical applications in treatment planning and monitoring. We demonstrate that 13C magnetic resonance spectroscopic imaging with hyperpolarized [1-13C]pyruvate shows the presence of tumor through an elevated lactate/pyruvate ratio in both contrast enhancing and non-enhancing brain tumor lesions including areas where tumor is undetectable on T2weighted MRI but present on histology.

3816.   7 Magnetization transfer imaging in a mouse model of orthotopic pancreatic cancer
Amir Moussavi1, Kristin Koetz1, Sanjay Tiwari1, and Susann Boretius1
1Section Biomedical Imaging, Department of Radiology and Neuroradiology, Christian-Albrechts-University, Kiel, Germany

Pancreatic ductal adenocarcinoma (PDAC) is still among the most devastating types of cancer characterized by infiltrative growth often with extensive fibrosis, the latter being an important predictor of poor chemotherapy response. In an orthotopic mouse model of PDAC with variable degree of fibrosis, we established and evaluated in-vivo radial imaging with magnetization transfer weighting. MT saturation correcting the MT-weighted signal for signal amplitude and T1 relaxation allowed quantification of tumor associated desmoplasia. Transfer of these methods to humans may allow individualized adjustments of chemotherapy.

3817.   8 In vivo Monitoring of Enzyme Activity in a Transgenic Breast Cancer Model with Hyperpolarized C-13 Metabolic Activity Decomposition MRSI
Zihan Zhu1,2, Peter J. Shin1,2, Christine Leon Swisher3, Peder E.Z. Larson1,2, Hsin-Yu Chen1,2, Hong Shang1,2, Eugene Milshteyn1,2, Robert A. Bok1, Andrei Goga4, and Daniel B. Vigneron1,2
1Department of Radiology and Biomedical Imaging, University of California, San Francsico, San Francisco, CA, United States, 2UC Berkeley-UCSF Graduate Program in Bioengineering, San Francisco, CA, United States, 3Massachusetts General Hospital and Harvard Medical School, MA, United States, 4Department of Cell and Tissue Biology, University of California, San Francsico, San Francisco, CA, United States

Molecular imaging with hyperpolarized C-13 substrates provides valuable metabolic exchange information non-invasively. In this work, the dynamic Metabolic Activity Decomposition Stimulated-echo Acquisition Mode (MAD-STEAM) sequence was applied to a switchable oncogene-driven breast cancer mouse model. The results showed the feasibility of using MAD-STEAM to detect enzymatic activity changes within tumor and demonstrated its potential to monitor tumor progression and regression.

3818.   9 Multi-Parametric mpMRI to Characterize Brain and Bone Metastases in Disseminated Breast Cancer
Natalie Julie Serkova1, Diana M Cittelly1, Kendra M Huber1, and Carol A Sartorius1
1University of Colorado Anschutz Medical Center, Aurora, Colorado, United States

Non-invasive multiparametric mpMRI of multifocal metastatic breast cancer provides characteristic MRI signatures for brain versus bone lesions in a mouse model of disseminated breast cancer. Brain metastatic phenotype is characterized by low vascularity and cell density as revealed by low Ktrans and ADC values, respectively. In future, quantitative mpMRI end-points have potential to stratify patients into “smart” targeted treatment regimens based on a particular tumor radiologiocal profile.

3819.   10 Source-based nosologic imaging of response to therapy in pre-clinical glioblastoma
Sandra Ortega-Martorell1,2, Ivan Olier3, Teresa Delgado-Gońi4, Magdalena Ciezka2,5, Ana Paula Candiota2,5, Margarida Juliŕ-Sapé2,5, Martí Pumarola2,5, Paulo Lisboa1, and Carles Arús2,5
1Liverpool John Moores University, Liverpool, Merseyside, United Kingdom, 2Networking Research Center on Bioengineering, Biomaterials and Nanomedicine, CIBER-BBN, Cerdanyola del Vallčs, Spain, 3The University of Manchester, Manchester, United Kingdom, 4The Institute of Cancer Research, London, United Kingdom, 5Universitat Autňnoma de Barcelona, Cerdanyola del Vallčs, Spain

A source-based extraction method is shown to produce nosological images allowing convenient non-invasive tracking of preclinical GBM response to therapy. The source-based classifier was developed from a training set of 14 C57Bl/6 mice harbouring GL261 GBM and validated in a further independent set of 24 additional mice using comparison with post-sacrifice histopathology.

3820.   11 Evaluation of metronomic chemotherapy in a mouse model using DCE-MRI and DWI
Melanie Freed1,2, Kerryanne Winters1,2, Jin Zhang1,2, and Sungheon G. Kim1,2
1Center for Advanced Imaging Innovation and Research (CAI2R), Dept. Radiology, NYU School of Medicine, New York, NY, United States, 2Bernard and Irene Schwartz Center for Biomedical Imaging, Dept. Radiology, NYU School of Medicine, New York, NY, United States

Metronomic chemotherapy is a promising method that delivers chemotherapy in low, frequent doses and has been shown to demonstrate superior response over traditional chemotherapy in some cases. There is a need to develop mouse models and techniques for evaluating dose and scheduling of metronomic chemotherapy to optimize its usage and benefits. In this study, we investigate the use of DCE-MRI and DWI to evaluate metronomic chemotherapy of BALB/c mice with implanted 4T1 mouse mammary tumor cells. Our data suggests this may be a good model for advanced breast cancer and that ADC values may be sensitive to early therapy response.

3821.   12 Molecular MR imaging of micrometastasis of breast cancer
Zhuxian Zhou1, Mohammed Qutaish1, Zheng Han1, Rebecca Schur1, David Wilson1, and Zheng-Rong Lu1
1Department of Biomedical Engineering, Case Western Reserve University, Cleveland, Ohio, United States

We evaluated a targeted contrast agent CREKA-Tris(Gd-DOTA)3 for MR molecular imaging of breast cancer micrometastases.

Tuesday 2 June 2015
Exhibition Hall 16:00 - 17:00

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3822.   13 MRI-based measurement of tissue O2
Scott C. Beeman1, Ying-Bo Shui2, John A. Engelbach1, Joseph J.H. Ackerman1,3, and Joel R. Garbow1
1Radiology, Washington University, Saint Louis, Missouri, United States, 2Ophthalmology, Washington University, Saint Louis, Missouri, United States,3Chemistry, Washington University, Saint Louis, Missouri, United States

Diatomic oxygen (O2), as found dissolved in tissue, is a critical component in aerobic metabolism and a fundamental determinant of physiological functional status. Reliable, non-invasive methods for measuring tissue O2 content are lacking. We quantify the relaxivity of brain-tissue O2 and, subsequently, changes in brain-tissue oxygenation in healthy brain, radiation lesions, and tumor lesions. By quantifying the change in brain tissue oxygenation with MRI, we were able to differentiate tumor lesions from radiation necrosis lesions – two pathologies that have proven extremely difficult to differentiate with common radiological techniques.

3823.   14 In vivo MRI-based 3-D Printed Molds and Individualized Tissue Sectioning Apparatuses Improve MRI-Histopathologic Co-Registration in Brain Cancer Patients
Alexander E. Salmon1, Brian J. Pellatt2, Nikolai J. Mickevicius3, Elizabeth J. Cochran4, and Peter S. LaViolette5
1Neuroscience, Medical College of Wisconsin, Milwaukee, WI, United States, 2Medical College of Wisconsin, Milwaukee, WI, United States, 3Biophysics, Medical College of Wisconsin, Milwaukee, WI, United States, 4Pathology, Medical College of Wisconsin, Milwaukee, WI, United States, 5Radiology, Medical College of Wisconsin, Milwaukee, WI, United States

Precise co-registration of brain tissue and medical imaging is critical for validation of novel imaging biomarkers. Brain tissue distortion during fixation and traditional brain sectioning techniques may complicate co-registration. To prevent tissue distortion, a clinical MRI-based mesh mold was 3D-printed for use during fixation. To obtain representative axial cuts, an individualized tissue sectioning apparatus was designed from a high resolution clinical scan and the slice profile of 6.5mm images. After sectioning, consistency, and co-registration error was analyzed by AFNI. Using a layer resolution of 0.40mm, printing cost for each brain was approximately $61 and printing duration was approximately 38 hours.

3824.   15 Gadolinium-free extracellular MR contrast agent for tumor imaging - permission withheld
Joris Tchouala Nofiele1, Inga E Haedicke2, Yong Le Zhu2, Xiao-an Zhang2, and Hai-Ling Margaret Cheng1,3
1Hospital for Sick Children, Toronto, Ontario, Canada, 2Chemistry, University of Toronto, Toronto, Ontario, Canada, 3Institute of Biomaterials & Biomedical Engineering, University of Toronto, Toronto, Ontario, Canada

Contrast administration is integral to tumor diagnostic imaging, and gadolinium (Gd)-based contrast agents are the current approved standard for clinical workflow. However, a number of patients, particularly those with impaired kidney function, are exempt from the benefits of a contrast-enhanced examination. In this study, we investigate the potential of a recently described novel extracellular and renally filtered manganese porphyrin T1 agent for tumor imaging. Results in tumor-bearing rats demonstrate that the new agent, MnTCP, exhibits similar pharmacokinetics but provides consistently greater enhancement than Gd-DTPA. MnTCP can potentially provide contrast-enhanced MRI for tumor diagnosis in a broader patient base.

Tuesday 2 June 2015
Exhibition Hall 16:00 - 17:00

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3825.   16 Monitoring gas-induced haemodynamic changes in the breast with BOLD contrast
Tess Catherwood1, Andrew Patterson1, Martin Graves1, Reem Bedair1, Roie Manavaki1, Mary McLean2, John Griffiths2, and Fiona Gilbert1
1Radiology, Cambridge University Hospitals NHS Foundation Trust, Cambridge, Cambridgeshire, United Kingdom, 2Cancer Research UK Cambridge Institute, Cambridge, Cambridgeshire, United Kingdom

BOLD contrast MRI with hyperoxic gas challenge may provide a biomarker of breast tumour oxygenation and vascular function, with the potential to predict treatment response. This study measured the strength of BOLD response to ‘carbogen-light’ (2% CO2) interleaved with medical air and oxygen, compared to an all-air control, in six healthy volunteers. ‘Carbogen-light’ was effective in inducing a measurable BOLD effect with respect to background physiological noise, without the respiratory discomfort often reported with 5% CO2 mixtures. In general ‘carbogen-light’ versus oxygen induced a larger response, consistent with the opposing vasomodulatory effects of these two stimuli.

3826.   17 Quantitative assessment of procedure success in MR-guided breast biopsy exams
Xiaofeng Liu1, E Morris2, Robert Darrow1, and Ileana Hancu1
1GE Global Research, Niskayuna, NY, United States, 2Memorial Sloan Kettering Cancer Center, NY, United States

Many factors contribute to MR-guided breast biopsy procedure success or failure. Significantly, there is no immediate verification of specimen retrieval and no quantitative measures to indicate adequate removal of the enhancing lesion. This work demonstrates a tool enabling quantitative assessment of success of MR-guided breast biopsy. Results from 4 patients indicated that the ratio between volumes of the suspicious lesion and total tissue removed in a biopsy procedure averaged 52%, ranging from 4% to 99%. The availability of real time quantitative assessment of lesion removal, prior to procedure completion, should enable improved verification of lesion sampling.

3827.   18 Accurate Discrimination of Benign and Malignant Breast Cancer in Suspicious Tumors Based on Semi-Quantitative DCE-MRI Employing Support Vector Machine
Saeedeh Navaei Lavasani1,2, Masoomeh Gity3, Mahnaz Nabil1,4, Anahita Fathi Kazerooni1,2, and Hamidreza Saligheh Rad1,2
1Quantitative MR Imaging and Spectroscopy Group, Research Center for Molecular and Cellular Imaging, Tehran University of Medical Sciences, Tehran, Iran,2Department of Medical Physics and Biomedical Engineering, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran, 3Department of Radiology, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran, 4Department of Statistics, Tarbiat Modares University, Tehran, Iran

Dynamic Contrast Enhanced-Magnetic Resonance Imaging (DCE-MRI) is widely used as sensitive tool in breast tumor diagnosis. Interpretation of breast MRI requires focusing not only on morphologic changes, but also on the quantification of the areas with increased enhancement. In this setting, accurate selection of quantitative parameters and classification approach could result in reliable tumor differentiation. We propose an accurate approach, based on support vector machine classification of dynamic features of suspicious tumors within the breast to discriminate malignant or benign breast lesions.

3828.   19 Evaluation of Benign and High-Risk, Nonmalignant Breast Lesions, assessed as False-Positive at Contrast-Enhanced (CE) MRI using DW imaging and CE MR Imaging Features
Sunitha B Thakur1, Jung Hun Oh2, Milans Soledad2, Harini Veeraraghavan2, Merlin M Gnanasigamani2, Elizabeth J Sutton2, Joseph O Deasy2, and Elizabeth A Morris2
1Memorial Sloan Kettering Cancer Center, New York, NY, United States, 2Memorial Sloan Kettering Cancer Center, NY, United States

Lesions that are classified ‘high-risk’ typically require complete surgical excision; a procedure that is expensive and can cause anxiety and morbidity. Therefore, the ability to distinguish between lesions, especially to differentiate the high-risk benign group from other benign lesions would be extremely helpful in a clinical setting. We conducted this study in order to evaluate the imaging characteristics of non-malignant lesions and classify them using (i) apparent diffusion coefficient (ADC) values, (ii) morphological and (iii) texture-based image features derived from contrast enhanced magnetic resonance imaging. We used 3.0T MRI data from 111 women and found that lower ADC values appear to correlate with high-risk breast lesions. This study is useful because it probes the concept of distinguishing not just between malignant and benign lesions but goes further to classify benign lesions into subgroups that could be treated differently at the clinical level.

3829.   20 Accurate Segmentation of Breast Lesions Based on Wavelet Kinetics: Comparison with Semi-Quantitative Features
Saeedeh Navaei Lavasani1,2, Masoomeh Gity3, Anahita Fathi Kazerooni1,2, and Hamidreza Saligheh Rad1,2
1Quantitative MR Imaging and Spectroscopy Group, Research Center for Molecular and Cellular Imaging, Tehran University of Medical Sciences, Tehran, Iran,2Department of Medical Physics and Biomedical Engineering, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran, 3Department of Radiology, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran

Breast cancer is a significant public health problem in the world. Automatic and objective analysis of DCE-MRI studies can greatly assist the radiologist to gain accurate evaluation of tumor size, malignancy and perfusion in the surrounding tissues, which is essential in diagnosis. In this work, we proposed breast lesion segmentation by means of fuzzy c-means clustering technique using wavelet kinetic and semi-quantitative features, extracted from the pixel-based time-signal intensity curves.

3830.   21 Fast bilateral breast coverage with high spectral and spatial resolution (HiSS) MRI at 3T
Milica Medved1, William A Weiss1, Hiroyuki Abe1, Gillian M Newstead1, Olufunmilayo I Olopade2, Maryellen L Giger1, and Gregory S Karczmar1
1Department of Radiology, University of Chicago, Chicago, Illinois, United States, 2Department of Medicine, University of Chicago, Chicago, Illinois, United States

High spectral and spatial resolution (HiSS) MR imaging provides excellent diagnostic images of breast cancer even without the use of contrast agent. We report on a fast implementation of HiSS MRI using parallel imaging at 3T to achieve clinically feasible imaging times in < 2 mm3 voxels, with full bilateral coverage. Non-contrast HiSS MRI can be used to obtain images of lesions without artifacts resulting from contrast administration. In addition, spectral information obtained with HiSS MRI can be used to improve detection of small amounts of glandular tissue and improve breast density measurements in risk assessment studies.

3831.   22 Prediction of neoadjuvant therapy response using multiparametric MRI at 3T
Lenka Minarikova1, Wolfgang Bogner1, Katja Pinker-Domenig2, Thomas Helbich2, Siegfried Trattnig1, and Stephan Gruber1
1MRCE, Department of Biomedical Imaging and Image-guided Therapy, Medical University of Vienna, Vienna, Austria, 2Division of Molecular and Gender Imaging, Department of Biomedical Imaging and Image-guided Therapy, Medical University of Vienna, Vienna, Austria

Response prediction during neoadjuvant chemotherapy (NAC) should have an important role in therapy plan modifications, which would result in increase of disease-free survival. In our study we measured breast cancer patients in three time points: before, during and after the NAC, using DCE and DWI MRI at 3T to look for potentially better response prediction markers. Our results suggest that multiparametric data measured during the ongoing NAC correspond better with histopathologic outcome than data measured after NAC completion. However, mean ADC values alone didn’t show any outcome prediction ability.

3832.   23 Fat suppression techniques for high resolution breast DCE MRI at 7 tesla: a qualitative and quantitative comparison
Tijl A. van der Velden1, Alexander M. Th. Schmitz1, Kenneth G.A. Gilhuijs1, Wouter B. Veldhuis1, Peter R. Luijten1, Vincent O. Boer1, and Dennis W.J. Klomp1
1Radiology, University Medical Center Utrecht, Utrecht, Utrecht, Netherlands

Fat suppression is essential in high-resolution DCE-MRI of the breast. While chemical shift selective excitation (i.e. ProSet) is sensitive to magnetic field distortions, Dixon techniques may be sensitive to T2* effects due to their multi echo acquisition (ME-Dixon), or to motion when applied as multi acquisition (MA-Dixon). In this study, we investigated the efficiency of these fat suppression techniques at ultra-high resolutions obtained at 7 tesla. In ten healthy volunteers ProSet revealed structural details that were not observed with Dixon. Despite a non-uniform fat suppression of ProSet, the technique remains superior in CNR and time efficiency over other techniques.

3833.   24 Statistical Assessment of Diffusion Weighted Signal Decay in Breast Cancer Tumors at 3T: Mono-exponential or Bi-exponential?
Jing Yuan1, Gladys G. Lo2, Oi Lei Wong1, Helen H.L. Chan2, Abby Y. Ding1, Ting Ting Wong3, and Polly S.Y. Cheung3
1Medical Physics and Research Department, Hong Kong Sanatorium & Hospital, Happy Valley, Hong Kong, China, 2Department of Diagnostic & Interventional Radiology, Hong Kong Sanatorium & Hospital, Happy Valley, Hong Kong, China, 3Breast Care Center, Hong Kong Sanatorium & Hospital, Happy Valley, Hong Kong, China

This study prompts to rigorously assess and statistically compare DWI signal fitting in malignant breast tumor by using mono-exponential ADC model and bi-exponential intra-voxel incoherent motion (IVIM) model via F-test. ROI-averaged analysis showed that more tumors (n=24) were significantly better fitted by bi-exponential than by mono-exponential models (n=14). In contrast, voxel-wise analysis showed that more voxels presented mono-exponential DWI signal decay in tumors. With clinically achievable SNR, IVIM-MRI should be helpful for ROI-averaged DWI fitting to characterize tumor microvascularity while voxel-wise IVIM values should be carefully interpreted with caution due to possible inaccuracy and high uncertainty.

Tuesday 2 June 2015
Exhibition Hall 16:00 - 17:00

  Computer #  
3834.   
25 Impact of Temporal Resolution on Diagnostic Performance of Quantitative DCE-MRI of Prostate Cancer: Evaluation using a Novel Golden-Angle Radial Compressed-Sensing Sequence and Single Contrast Injection
Nainesh Parikh1, Justin Ream1, Tobias Block2, Weisheng Xu3, Hersh Chandarana1, Li Feng2, Samir Taneja4, and Andrew Rosenkrantz1
1Radiology, NYU School of Medicine, New York, NY, United States, 2Radiology, Center for Advanced Imaging Innovation and Research NYU School of Medicine, New York, NY, United States, 3Pathology, NYU School of Medicine, New York, NY, United States, 4Urologic Oncology, NYU School of Medicine, New York, NY, United States

We used a novel DCE-MRI sequence [Golden-angle RAdial Sparse Parallel (GRASP)] that employees compressed sensing and continuous radial acquisition to retrospectively reconstruct prostate DCE-MRI data obtained after a single contrast injection at temporal resolutions varying between approximately 1 and 10 seconds. The temporal resolution did not impact diagnostic performance of quantitative DCE metrics for tumor detection.

3835.   26 Unsupervised quality control of prostate MRSI using Non Negative Matrix Factorization
Nassim Tayari1, Anca R. Croitor Sava2, Diana M. Sima2, Sabine Van Huffel2, and Arend Heerschap1
1Department of Radiology and Nuclear Medicine, Radboud University Medical Center, Nijmegen, Netherlands, 2Department of Electrical Engineering, Katholieke Universiteit Leuven, Leuven, Belgium

An automated quality control algorithm plays an important role in automation of the analysis of MRSI data of the prostate cancer patients. In this work we present an automated unsupervised quality control algorithm for 3D 1H MRSI data sets. The method is based on feature extraction using Non Negative Matrix Factorization(NNMF). Consensus decisions of spectral quality judged by four experts is used as a Gold Standard for performance evaluation showing that the algorithm can separate good quality from bad quality spectra with 90% sensitivity and 90% specificity.

3836.   27 Development of Quantitative Multi-Parametric MRI Models for Prostate Cancer Assessment using Registered Correlative Pathology
Gregory J. Metzger1, Chaitanya Kalavagunta1, Stephen C Schmechel2, Patrick J. Bolan1, Badrinath Konety3, Benjamin Spilseth4, Christopher A. Warlick3, and Joseph S. Koopmeiners5
1Center for Magnetic Resonance Research, University of Minnesota, Minneapolis, MN, United States, 2Department of Pathology, University of Washington, Washington, United States, 3Department of Urologic Surgery, University of Minnesota, Minneapolis, MN, United States, 4Department of Radiology, University of Minnesota, Minneapolis, MN, United States, 5Division of Biostatistics, University of Minnesota, Minneapolis, MN, United States

A process is presented for generating critical correlative pathology for developing predictive models from voxel-wise mpMRI data based on mapping regions of disease from assembles pathology to in vivo MRI. The models generated from this novel data show improved performance over single quantitative MRI parameters for detection. The generation of composite biomarker maps has the potential to improve the use of mpMRI in the management of prostate cancer by providing a quantitative means to assess and monitor disease.

3837.   28 Computer Aided Quantitative Analysis of T2-Weighted prostate MR Images
Kai Zhao1, Chengyan Wang2, Juan Hu1, Xiaodong Zhang1, Jue Zhang2, and Xiaoying Wang1
1Department of Radiology, Peking University First Hospital, Beijing, Beijing, China, 2College of Engineering, Peking University, Beijing, Beijing, China

We extract 12 quantitative features from the T2 weighted images of prostate cancer and non-cancer by CAD, within the central gland and peripheral zone of the prostate, respectively.You can find out which feature can differ cancer from non-cancer better and the different feature weight of each feature in our research. This could be widely used and help us in the prostate cancer diagnosis.

3838.   29 Intraprostatic Lipid Spectroscopic Imaging of the Prostate Cancer
Xin Li1, Jackilen Shannon1, Mark G Garzotto1,2, Chris Amling1, William J Woodward1, George Thomas1, Elizabeth Dacey1,2, Xiaohua Wang1,2, Paige Farris1, Wesley Stoller2, Ann Martinez Acevedo1, Amy Palma1, Manoj K Sammi1, William D Rooney1, Fergus V Coakley1, and Jonathan Q Purnell1
1Oregon Health & Science University, Portland, Oregon, United States, 2Portland VA Medical Center, Portland, Oregon, United States

The lipogenic fatty acid synthase (FAS) is responsible for de novo fatty acid and triglyceride synthesis in tissue. Recently, FAS has been characterized as an oncogene and its overexpression is reported in several cancers which include that of the prostate. The altered lipid deposition of cancerous tissue thus can potentially be an independent biomarker for cancer aggressiveness monitoring. In this work, MR spectroscopic imaging (MRSI) is used to quantify prostatic lipid concentration for prostate cancer.

3839.   30 Zone Specific ADC + DCE-MRI Composite Maps to Aid in the Detection and Evaluation of Prostate Cancer
Naira Muradyan1, Osama Elbuluk2, Baris Turkbey2, Sandeep Sankineni2, Maria J Merino3, Senthil Periaswamy1, Marcelino Bernardo2, Francois Cornud4, and Peter L Choyke2
1iCAD, Inc., Nashua, NH, United States, 2Molecular Imaging Program, NCI, NIH, Bethesda, MD, United States, 3Laboratory of Pathology, NCI, NIH, Bethesda, MD, United States, 4Tourville Imaging Centre, Paris, France

This study describes a combined analysis method of Diffusion Weighted and Dynamic Contrast Enhanced MRI for prostate imaging, which minimizes the need for separate evaluation of these sequences. Images of 105 patients from two sites were used retrospectively to develop and test the prostate zone-specific composite colormaps, showing better accuracy than standalone Apparent Diffusion Coefficient outcome. Such objective display of combined information, which could be easily added to routine imaging, may be useful for lesion visualization, evaluation and minimizing reader variability during multiparametric prostate imaging.

3840.   31 Performance of High b-Value DWI in identifying high risk prostate cancer patients
Francesca Mertan1,2, Harsh K Agarwal2,3, Sandeep Sankineni2, Marcelino Bernardo2,4, Dagane Daar2,4, Maria Merino2, Bradford Wood2, Peter Pinto2, Peter L Choyke2, and Baris Turkbey2
1Grove City College, Grove City, PA, United States, 2National Institutes of Health, Bethesda, MD, United States, 3Philips Research NA, Briarcliff Manor, New York, United States, 4Leidos Biomedical Research Inc., Frederic National Laboratory for Cancer Research, Frederick, MD, United States

ADC maps have been shown to detect and stage prostate cancer. However, at high b-value (b>800mm/s2) DWI signal from tumor tissue does not follow the mono-exponential diffusion decay. Therefore high b-value DWI is typically accessed as part of prostate MRI reading. In this abstract we have shown that the performance of high b-value DWI to detect high risk prostate cancer patients improves with the increase in b-value and its performance did not change significantly with the increase in data acquisition time from 23msec to 102msec for b≥0s/mm2 DWI. High b-value DWI also performed better than ADC from b≤750s/mm2.

3841.   32 Hyperpolarized Lactate Production Correlates with Gleason Grade in Patient-Derived Tissues of Prostate Cancer
Renuka Sriram1, Mark Van Criekinge1, Justin DeLos Santos1, Daniel B Vigneron1, Robert Bok1, Donna Peehl2, Kayvan Rahimi Keshari3, and John Kurhanewicz1
1University of California, San Francisco, San Francisco, CA, United States, 2Stanford University, CA, United States, 3Memorial Sloan Kettering Cancer Center, New York, United States

The goal of the current study was to correlate hyperpolarized lactate with the pathologic grade of prostate cancer using living human prostate tissue slices (TSCs) obtained at surgery in a MR compatible 3D tissue culture bioreactor. TSCs obtained from 38 radical prostatectomy patients were studied after injection of hyperpolarized pyruvate and demonstrated that in addition to increased lactate production, high grade prostate cancer had significantly higher lactate efflux. Knowledge of significant extracellular HP lactate in aggressive prostate cancer will be useful for improving interpretation of the in vivo HP signals and interrogated using diffusion weighted HP 13C MR approaches.

3842.   33 Development of a Screening MRI Protocol for the Detection of Prostate Cancer: Initial Experience
Shivani Pahwa1, Robert Abouassaly2, Yun Jiang3, Karin Herrmann4,5, Raj Paspulati5,6, William Tabayoyong7, Soham Shah7, Brian Minnillo7, Gregory MacLennan7, Mark Griswold1,8, Lee Ponsky5,9, and Vikas Gulani5,10
1Radiology, Case Western Reserve University, Cleveland, Ohio, United States, 2University Hospitals, Ohio, United States, 3Biomedical Engineering, Case Western Reserve University, Cleveland, Ohio, United States, 4Radiology, University Hospitals, Ohio, United States, 5CWRU School of Medicine, Ohio, United States, 6UH Case Medical Center, Ohio, United States, 7Urology, University Hospitals, Ohio, United States, 8Biomedical Engineering, Case Western Reserve University, Ohio, United States, 9Urology, UH Case Medical Center, Ohio, United States, 10Radiology, UH Case Medical Center, Ohio, United States

Serum PSA measurement and digital rectal examination (DRE) are the current standards of care for detection of prostate cancer. However, the performance of these methods as screening tools has been criticized because they over diagnose a large number of patients with clinically insignificant disease, adding to a significant morbidity for the patient without improving the outcome. We propose a novel, short non-contrast imaging protocol as a secondary screening tool that helps direct targeted biopsies on suspicious lesions. Our preliminary experience indicated that this strategy increases the accuracy of detecting clinically significant disease, and improves risk stratification for biopsy.

3843.   34 Small Field-of-view single-shot EPI-DWI of the prostate: Evaluation of spatially-tailored two-dimensional radiofrequency excitation pulses
Daniel Hausmann1, Nils Rathmann1, Metin Sertdemir1, Philipp Riffel1, Anja Weidner1, Stephan Kannengiesser2, John N. Morelli3, Stefan O. Schoenberg1, and Ulrike I. Attenberger1
1Institute of Clinical Radiology and Nuclear Medicine, University Medical Center Mannheim, Medical Faculty Mannheim, University of Heidelberg, Germany, Mannheim, Baden-Württemberg, Germany, 2MR Applications Development, Siemens Healthcare, Erlangen, Germany, 3Department of Radiology, St. John’s Medical Center, Tulsa, Oklahoma, United States

The use of spatially-tailored, two-dimensional radiofrequency (RF) excitation pulses in single-shot echo-planar imaging (EPI), combined with a decreased FOV in the phase-encoding direction, results in a reduced amount of k-space acquisition lines, which shortens the EPI echo train length (ETL) and reduces susceptibility artifacts without an increase in acquisition time. Zoomed EPI leads to significant improvements in image quality and artifacts as well as image blur reduction improving prostate DWI and enabling accurate fusion with conventional sequences.

3844.   35 The ADC ratio of tumour to normal prostate as a robust method for quantifying diffusion weighted imaging of the prostate - permission withheld
Tristan Barrett1, Andrew N Priest2, Edward M Lawrence1, Debra Goldman3, Vincent J. Gnanapragasam4, Evis Sala5, and Ferdia A. Gallagher1
1Radiology, Cambridge University Hospitals, Cambridge, Cambridgeshire, United Kingdom, 2Cambridge University Hospitals, Cambridge, Cambridgeshire, United Kingdom, 3Department of Epidemiology and Biostatistics, Memorial Sloan Kettering Cancer Center, New York, New York, United States, 4Urology, Cambridge University Hospitals, Cambridge, Cambridgeshire, United Kingdom, 5Radiology, Memorial Sloan Kettering Cancer Center, New York, New York, United States

We investigate the ability of apparent diffusion coefficient (ADC) ratios of tumour-to-normal prostate to improve concordance between ADC values obtained from different b-value combinations within the same patients. Whole gland histopathology was used as a gold-standard. Concordance correlation between different b-value combinations was higher for ADC ratios compared to absolute ADC values. ADC maps incorporating a b-0 value demonstrated greater variability for both ratio and absolute values, likely relating to pseudo-perfusion effects. ADC ratios showed stronger inverse relationships to Gleason grade than absolute values. ADC ratios may therefore provide a more robust means of assessing restricted diffusion in the prostate.

3845.   36 Investigation of reduced FOV CEST in probing prostate cancer
Chunmei Li1, Bing Wu2, and Min Chen1
1Beijing Hospital, Beijing, Beijing, China, 2GE healthcare China, Beijing, Beijing, China

We investigate the use of a novel reduced FOV CEST method that allows us to zoom in the prostate region that helps delineating the tumor region from the benign region and improves accuracy in grading using CEST. The use of reduced FOV CEST in prostate was validated by comparing the APT map and MTRasym to those obtained using normal CEST, highly consistent results were obtained despite its lower intrinsic SNR. Reduced FOV CEST has the advantage of revealing the heterogeneity of the prostate, which may be difficult due to the constrained portion of the prostate region in normal FOV image.

3846.   37 Prostate Diffusion Distortion Correction with Restriction Spectrum Imaging
Rebecca Rakow-Penner1, Nathan White1, Daniel Margolis2, J. Kellogg Parsons3, Natalie Schenker-Ahmed1, Joshua Kuperman1, Hauke Bartsch1, Hyung Choi2, William Bradley1, Ahmed Shabaik4, Jiaoti Huang5, Michael Liss6, Leonard Marks7, Christopher Kane3, Robert Reiter7, Steven Raman2, David Karow1, and Anders Dale1
1Radiology, University of California San Diego, San Diego, CA, United States, 2Radiology, University of California Los Angeles, Los Angeles, California, United States, 3Urology, University of California San Diego, San Diego, CA, United States, 4Pathology, University of California San Diego, San Diego, CA, United States, 5Pathology, University of California Los Angeles, Los Angeles, CA, United States, 6Urology, University of Texas Health Science Center San Antonio, San Antonio, TX, United States, 7Urology, University of California Los Angeles, Los Angeles, CA, United States

Distortion maps were generated to reflect the offset of the collected data versus the corrected data.

3847.   38 Discriminating low-grade from high-grade peripheral zone prostate cancer by multiparametric MRI: a multicenter study
Marnix C. Maas1, Geert J.S. Litjens1,2, Alan J. Wright3, Masoom A. Haider4, Katarzyna J. Macura5, Kirsten M. Selnćs6, Daniel J.A. Margolis7, Thomas Helbich8, Berthold Kiefer9, Jurgen J. Fütterer1, and Tom W.J. Scheenen1
1Radiology and Nuclear Medicine, Radboud University Medical Center, Nijmegen, GLD, Netherlands, 2Pathology, Radboud University Medical Center, Nijmegen, GLD, Netherlands, 3Cancer Research UK Cambridge Institute, University of Cambridge, Cambridge, United Kingdom, 4Sunnybrook Health Sciences Center, University of Toronto, Toronto, ON, Canada, 5Russel H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University, Baltimore, MD, United States, 6Department of Circulation and Medical Imaging, Norwegian University of Science and Technology, Trondheim, Norway, 7Radiology, UCLA David Geffen School of Medicine, Los Angeles, CA, United States, 8Biomedical Imaging and Image-guided Therapy, Medical University Vienna - General Hospital Vienna, Vienna, Austria, 9Siemens AG Healthcare, Erlangen, Germany

This study investigates the ability of multiparametric MRI (mpMRI) including DWI, 1H-MRSI and DCE-MRI to discriminate low-grade from higher-grade peripheral zone (PZ) prostate cancer in a multi-center setting, using whole-mount section histopathology as the gold standard. Guided by histology and blinded to functional imaging, ROIs were defined on T2w imaging in PZ tumors in 39 patients from 5 centers, and transferred to functional parameter maps. ROC analysis resulted in areas under the curve of 0.80±0.13 for ADC and 0.83±0.15 for a multivariate model including both ADC and MRSI. Multicenter mpMRI can yield good separation between low and higher grade PZ tumors.

3848.   39 Quantitative differentiation of prostate cancer from normal peripheral zone using Magnetic Resonance Fingerprinting (MRF) and Diffusion Mapping
Chaitra Badve1, Alice Yu2, Shivani Pahwa3, Matthew Rogers2, Yun Jiang4, Yiying Liu5, Mark Schluchter5, Lee Ponsky6,7, Mark Griswold4, and Vikas Gulani1,3
1Radiology, University Hospitals, Cleveland, Ohio, United States, 2School of Medicine, Case Western Reserve University, Cleveland, Ohio, United States,3Radiology, Case Western Reserve University, Cleveland, Ohio, United States, 4Biomedical Engineering, Case Western Reserve University, Cleveland, Ohio, United States, 5Biostatistics, Case Western Reserve University, Cleveland, Ohio, United States, 6Urology, University Hospitals, Cleveland, Ohio, United States,7Urology, Case Western Reserve University, Cleveland, Ohio, United States

Magnetic resonance fingerprinting (MRF) was acquired in patients with clinical suspicion of prostate cancer. After diagnoses were confirmed by pathology, T1 and T2 values from MRF were used with ADC values to retrospectively separate malignancy from normal peripheral zone (NPZ). All MR parameters showed significant difference between prostate cancer and NPZ. Furthermore, T2 and ADC used in conjunction had a high discriminatory power (AUC = 0.996). Further research is needed to determine the robustness of using T2 and ADC to identify prostate cancer prospectively, and to explore the possibly utility of T1 in identifying malignancy.

3849.   40 Evaluation of the diagnostic differentiation of prostate cancer from benign prostate hyperplasia using Intra-voxel incoherent motion MR imaging
Meiyu Sun1, Ailian Liu1, Ye Li1, Lihua Chen1, Qingwei Song1, Bin Xu1, and Ziheng Zhang2
1the first affiliated hospital of Dalian Medical University, Dalian, Liaoning, China, 2GE healthcare China, Beijing, China

The MR imaging of prostate cancer (PCa) was undistinguishable from that of benign prostatic hyperplasia (BPH) on conventional T2WI and dynamic contrast enhancement imaging. In this study, intravoxel incoherent motion (IVIM) DWI were performed to investigate the diffusion and perfusion features of PCa and BPH, and to evaluate the relationship of the parameters, standard ADC, slow ADC, fast ADC and fraction of fast ADC, as well as their sensitivity and specificity in diagnosis. It was demonstrated standard ADC and slow ADC from IVIM MRI maybe a significant MRI biomarkers to differentiate PCa from BPH with satisfying sensitivity and specificity.

3850.   41 The role of multiparametric MRI in detection of prostate cancer in patients with total serum prostate specific antigen levels of 4-10 ng/mL: a prospective cohort study
Rui Wang1, Juan Hu1, Yuanyuan Jiang1, and Xiaoying Wang1
1Radiology, Peking university first hospital, Beijing, Beijing, China

In patients with PSA levels of 4-10 ng/mL, it is difficult to distinguish prostate cancer (PCa) from prostatitis. So our study is to evaluate the role of multiparametric MRI (mp-MRI) in detection of PCa and prediction of PCa incidence in patients with total PSA levels of 4¨C10 ng/mL by a prospective cohort study. Mp-MRI showed excellent area under the ROC curve, suggesting obviously clinically relevant predictive characteristics. Furthermore, with 137 months of follow-up, higher score of mp-MRI was proved to be significantly associated with a greater risk of detection rate of PCa.

3851.   42 Saturation duration and power optimization for APT MRI of prostate cancer
Harsh K Agarwal1,2, Jochen Keupp3, Marcelino Bernardo2, Baris Turkbey2, and Peter L Choyke2
1Philips Research NA, Briarcliff Manor, New York, United States, 2National Institutes of Health, Bethesda, MD, United States, 3Philips Research Laboratories, Hamburg, Germany

Amide proton transfer (APT) MRI has been shown to localize and stage prostate. However there are multiple parameters such as saturation power and saturation duration that affect the APT MRI contrast. In this abstract we have shown that MTR asymmetry increased with the decrease in the pulse duration. Also the peak of MTR asymmetry shifted with the change in saturation power. However spurious MTR was observed over prostate especially in peripheral zone which could be due to the incoherent motion such as rectal spasm.

3852.   43 Correlation between diameter of prostate cancer foci on multiparametric prostate MRI and whole mount histopathology: Stratified by PI-RADS and Gleason Score
Pooria Khoshnoodi1, Nelly Tan1, Daniel J. A. Margolis1, Wei-Chan Lin1, Somrach Thamtorawat1, David Y. Lu2, Jiaoti Huang2, Robert E. Reiter3, and Steven S. Raman1
1Radiology, University of California, Los Angeles, Los Angeles, California, United States, 2Pathology, University of California, Los Angeles, Los Angeles, California, United States, 3Urology, University of California, Los Angeles, Los Angeles, California, United States

Multiparametric magnetic resonance imaging (MP-MRI) is used more frequently to detect and evaluate prostate cancer (CaP). We studied the size of the tumor prior to surgery on MP-MRI and its correlation with the actual size of tumor on pathology after prostatectomy. This correlation was stratified by overall PI-RADS suspecious score on multiparametric MRI and also Gleason Score at histopathology.

3853.   44 Diagnostic accuracy of NaF PET-MRI in differentiating bone metastases from benign bone lesions in metastatic prostate cancer.
Taylor Stone1 and Luis Beltran2
1New York University, New York, NY, United States, 2New York University, NY, United States

NaF PET-MRI as a hybrid imaging study shows higher specificity, sensitivity, and overall accuracy than bone scintigraphy, PET or MRI in isolation in differentiating between metastatic and benign bone lesions. Accurately defining the number of lesions has important treatment implications as prostate cancer treatment is generally based on disease burden.

3854.   45 Combined MR Volumetry and Diffusion Weighted imaging to better predict clinically significant prostate cancer on MRI/Ultrasound fused guided biopsy?
Stephanie Nougaret1, Nicola L Robertson1, Evis Sala1, Hedvik Hricak1, Behfar Ehdaie2, and Hebert A Vargas1
1Radiology department, Memorial Sloan Kettering Cancer Center, New York, NY, United States, 2Urology department, Memorial Sloan Kettering Cancer Center, New York, NY, United States

To evaluate the combined efficacy of MR Volumetry and Diffusion Weighted Imaging (DWI), in the detection of clinically significant prostate cancer using MRI-US fusion biopsy. This preliminary study demonstrates the potential added predictive value of using tumor volumetry in combination with DWI, in the diagnosis of clinically significant prostate cancer using MRI-US fusion biopsy. Furthermore, it evaluates the feasibility of quantitative assessment in tumor burden.

3855.   46 Clinical Application of 3D High Resolution Multi-shot Diffusion-Weighted MRI in Prostate Cancer Patients undergoing Active Surveillance Protocol for Low-Risk Prostate Cancer
Christopher Nguyen1,2, Ali-Reza Sharif-Afshar3, Zhaoyang Fan1, Sidney Wilson2, Xiaoming Bi4, Lucas Payor5, Rola Saouaf5, Hyung Kim3, and Debiao Li1,2
1Biomedical Imaging Research Institute, Cedars Sinai Medical Center, Los Angeles, CA, United States, 2Bioengineering, University of California Los Angeles, Los Angeles, CA, United States, 3Surgery / Urology, Cedars-Sinai Medical Center, Los Angeles, CA, United States, 4Siemens Healthcare, Los Angeles, CA, United States, 5Radiology, Cedars-Sinai Medical Center, Los Angeles, CA, United States

In a small group of prostate cancer patients undergoing active surveillance (AS-PC) patients, a recently developed novel 3D diffusion-prepared multi-shot balanced steady-state free precession technique demonstrated improved suspicious low risk prostate cancer lesion detection compared with single-shot diffusion-weighted echo planar imaging (SS-DW-EPI). We conducted a follow-up study in a significantly larger cohort to further investigate the clinical impact of the proposed technique. The proposed technique continued to yield significantly better lesion detection of biopsy-confirmed lesions compared with SS-DW-EPI. By improving lesion detection, the proposed technique may allow DW MRI to potentially monitor low-risk prostate cancer lesions in AS-PC.

Tuesday 2 June 2015
Exhibition Hall 16:00 - 17:00

  Computer #  
3856.   49 Constrained multi-agent tracer-kinetic modeling to assess tumor vascular changes induced by DMXAA treatment
Igor Jacobs1, Stefanie Hectors1, Gustav Strijkers1,2, Klaas Nicolay1, and Matthias Schabel3,4
1Biomedical NMR, Department of Biomedical Engineering, Eindhoven University of Technology, Eindhoven, Netherlands, 2Biomedical Engineering and Physics, Academic Medical Center, University of Amsterdam, Amsterdam, Netherlands, 3Advanced Imaging Research Center, Oregon Health and Science University, Portland, Oregon, United States, 4Utah Center for Advanced Imaging Research, University of Utah, Salt Lake City, Utah, United States

Accurate evaluation of antivascular tumor therapies requires detailed analysis of vascular alterations. We have recently proposed a novel multi-agent tracer-kinetic modeling approach for DCE-MRI, which allows simultaneous and self-consistent assessment of blood flow and permeability within one imaging session. In the present study, we have applied this approach to evaluate DMXAA treatment. An early increase in extraction fraction of the dendrimer-based contrast agents and reduced blood flow were simultaneously observed, thereby identifying increased permeability as the main mechanism of DMXAA-induced vascular shutdown, in agreement with literature. This demonstrates the potential of the multi-agent approach to assess therapy-induced vascular changes.

3857.   50 Micro-vascular effects of photodynamic therapy in tumors evaluated with dynamic contrast-enhanced MRI
Tom Schreurs1,2, Stefanie Hectors1, Igor Jacobs1, Holger Grüll1,3, Gustav Strijkers1,2, and Klaas Nicolay1
1Biomedical Engineering, Eindhoven University of Technology, Eindhoven, Netherlands, 2Biomedical Engineering and Physics, Academic Medical Center, Amsterdam, Netherlands, 3Oncology Solutions, Philips Research, Eindhoven, Netherlands

Micro-vascular effects of photodynamic therapy (PDT) were assessed using Dynamic Contrast Enhanced (DCE) MRI in a mouse tumor model. PDT is an emerging cancer therapy based on a light-activated drug. DCE-MRI showed that tumors were almost completely perfused before PDT, but partly non-perfused after 1 hour and largely non-perfused after 24 hours. The results clearly indicated PDT-induced vascular occlusion. Remaining enhanced regions coincided with tumor recurrences. This work shows that DCE-MRI has large potential to monitor PDT efficacy, early after treatment.

3858.   51 Multiparametric MRI analysis for the evaluation of MR-guided High Intensity Focused Ultrasound treatment
Stefanie Hectors1, Igor Jacobs1, Edwin Heijman2, Jochen Keupp3, Monique Berben2, Gustav Strijkers1,4, Holger Grüll1,2, and Klaas Nicolay1
1Biomedical NMR, Department of Biomedical Engineering, Eindhoven University of Technology, Eindhoven, Netherlands, 2Oncology Solutions, Philips Research Europe, Eindhoven, Netherlands, 3Tomographic Imaging Systems, Philips Research Europe, Hamburg, Germany, 4Biomedical Engineering and Physics, Academic Medical Center, University of Amsterdam, Amsterdam, Netherlands

A multiparametric MRI protocol, consisting of quantitative T1, T2, ADC, amide proton transfer (APT) and T measurements, was used to evaluate MR-guided HIFU treatment of subcutaneous rat tumors. K-means clustering was performed on the multiparametric data using all different combinations (feature vectors) of MRI parameters. For feature vector {ADC, APTw signal} a strong correlation (r=0.92) between histology-derived and clustering-derived non-viable tumor fractions was observed, which was higher than correlations between histology-derived non-viable fractions and HIFU-treated fractions derived from MR thermometry and dynamic contrast-enhanced MRI. In conclusion, our data demonstrate that a multiparametric MR analysis can accurately identify HIFU-treated tumor tissue.

3859.   52 Prediction of Treatment Response and Tumor Recurrence Using MR Elastography - permission withheld
Kay Pepin1, Steven Ansell2, Richard L Ehman3, and Kiaran McGee3
1Graduate School, Mayo Clinic, Rochester, Minnesota, United States, 2Hematology, Mayo Clinic, Minnesota, United States, 3Radiology, Mayo Clinic, Minnesota, United States

Change in tumor mechanical properties measured using MR Elastography may be a biomarker of response to chemotherapy. The ability to determine failure to therapy is a critical function of an imaging biomarker. The results of this animal study demonstrate that MRE is sensitive to an increase in tumor stiffness prior to an increase in tumor volume. Similarly, change in tumor shear stiffness is dose-dependent; the higher the chemotherapy dose the greater the subsequent decrease in tumor stiffness. These results suggest that MRE-derived shear stiffness measurements reflect the observed response to chemotherapy.

3860.   53 Metabolic Imaging of Early Tumor Therapy
Charles S. Springer1,2, Xin Li3, Mohan L. Jayatilake4, Martin M. Pike2,3, William D. Rooney3, Rosalie C. Sears2,5, and Wei Huang2,3
1Advanced Imaging Research Center, Oregon Health & Science University, Portland, Or, United States, 2Knight Cancer Institute, Oregon Health & Science University, Portland, Oregon, United States, 3Advanced Imaging Research Center, Oregon Health & Science University, Portland, Oregon, United States,4Radiography and Radiotherapy, University of Peradeniya, Peradeniya, Peradeniya, Sri Lanka, 5Molecular and Medical Genetics, Oregon Health & Science University, Portland, Oregon, United States

Normally, DCE-MRI estimates vascular parameters, Ktrans and vp. However, shutter-speed analysis allows determination of cellular, metabolic parameters, kio and vi. The kio quantity tracks cell membrane Na+,K+-ATPase activity. Exemplified with human and murine breast cancers, we show that these enable the discrimination of cytotoxic and targeted therapies in their early actions.

3861.   54 Immunocytokine facilitation of natural killer cells accumulation in tumors
Naomi S. Sta Maria1, Samuel R. Barnes1, David Colcher2, Andrew A. Raubitschek2, and Russell E. Jacobs1
1Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, United States, 2Cancer Immunotherapeutics & Tumor Immunology, City of Hope, Duarte, CA, United States

We investigated whether the priming of tumors with immunocytokines can potentiate the accumulation of adoptive human natural killer cells labeled with ferumoxytol, an FDA-approved USPIO, in tumors. We used T2* weighted multi-gradient echo to generate parametric R2* maps of the tumors in NOD-scid-gamma-null mice with human colorectal adenocarcinoma cells, LS-174T.luc. Mice were differentiated into control or immunocytokine treated groups and were imaged pre and post (5hr and 10hr) injection of NK cells. Pretreated mice showed significant increases in tumor R2* values at the 10hr time point. MRI can be used to assess efficacy of adoptive NK cell transfer.

3862.   55 Whole body mDixon MRI in multiple myeloma: Quantitative derived parameters changes following chemotherapy
Arash Latifoltojar1, Margaret Hall-Craggs2, Alan Bainbridge2, Stuart Taylor3, Kwee Yong3, Neil Rabin2, Matthew Benger2, Liam Watson2, Michelle Siu2, and Shonit Punwani3
1University College London, London, London, United Kingdom, 2University College London Hospital, London, United Kingdom, 3University College London, London, United Kingdom

Whole body anatomical and functional MRI is being increasingly used for initial assessment and treatment response monitoring in patients with multiple myeloma. The replacement of the normal fatty marrow cells by neoplastic cells in multiple myeloma and its changes following therapy could be explored, using quantitative derive parameters from MR imaging. In this study we investigated the changes in quantitative derived parameters from whole body mDixon changes following therapy in patients with multiple myeloma.

3863.   56 DCE-MRI kinetic model and curve pattern analyses for predicting response and survivals in osteosarcoma patients
Junyu Guo1 and Wilburn E. Reddick1
1Radiological Sciences, St Jude Children's Research Hospital, Memphis, TN, United States

This study investigated two DCE-MRI data analysis methods for evaluating response to treatment and prognosis of event-free-survival (EFS) and overall-survival in 42 patients with osteosarcoma. In two methods, eight parameters and their absolute-difference (ABD) between two neighboring time points were assessed for the role of predicting clinical results. Three ABD parameters before week5 could potentially predict response. The CPA parameter lower case Greek betalower case Greek tau on Day5 is the potential prognostic factor for EFS. Four ABD parameters before week5 are potential prognostic factors for overall-survival. All results show that two DCE-MRI analysis methods could provide valuable predictive information for clinical outcomes.

3864.   57 Predicting Response to Sunitinib Second-line Therapy in Gastrointestinal Stromal Tumors Using Non-Gaussian Diffusion MRI
Yi Sui1,2, Lei Tang3, Kejia Cai2,4, Shun-Yu Gao3, Frederick C. Damen2,4, Ying-Shi Sun3, and Xiaohong Joe Zhou2,5
1Bioengineering, University of Illinois at Chicago, Chicago, IL, United States, 2Center for MR Research, University of Illinois Hospital & Health Sciences System, Chicago, IL, United States, 3Radiology, Peking University Cancer Hospital & Institute, Beijing, China, 4Radiology, University of Illinois Hospital & Health Sciences System, Chicago, IL, United States, 5Departments of Radiology, Neurosurgery and Bioengineering, University of Illinois Hospital & Health Sciences System, Chicago, IL, United States

Sunitinib offers a second line treatment to gastrointestinal stromal tumor (GIST) patients with imatinib-resistant progressive lesions. Prediction of the treatment response is crucial for achieving optimal outcomes. We used a non-Gaussian diffusion model, known as the fractional order calculus model (FROC), to assess the early response to sunitinib treatment in imatinib-resistant GIST lesions. Our results showed that the FROC model outperformed the conventional means of using tumor size in predicting tumor response at as early as 2 weeks after receiving sunitinib treatment. This study suggests that non-Gaussian diffusion imaging can provide timely information to evaluate sunitinib targeted therapy of GIST.

3865.   58 DCE-MRI Assessment of Soft-Tissue Sarcoma Response to Preoperative Therapy
Wei Huang1, Megan L Holtorf1, Aneela Afzal1, Yiyi Chen1, Brooke R Beckett1, and Christopher W Ryan1
1Oregon Health & Science University, Portland, OR, United States

Twenty patients with extremity soft-tissue sarcoma who underwent preoperative chemoradiotherapy consented to research DCE-MRI, performed before, after one cycle of chemotherapy, and after completion of therapy before surgery. Ktrans and kep at baseline, after one cycle of therapy, and percent change were much better than RECIST tumor size measurement for early prediction of therapy response. Post-therapy Ktrans, ve, and kep were negatively correlated with necrosis percentage (NP) of the surgical specimen. No significant relationship was observed between post-therapy RECIST and NP.

3866.   59 Feasibility of performing weekly intravoxel incoherent motion DW-MRI and monitoring anatomical and functional changes in nasopharynx tumors during chemoradiation therapy - permission withheld
Yonggang Lu1, Nancy Lee1, Vaois Hatzoglou1, Nadeem Riaz1, Joseph O. Deasy1, and Amita Shukla-Dave1
1Memorial Sloan-Kettering Cancer Center, NEW YORK, New York, United States

Our aim is to identify imaging biomarkers predictive of treatment response in nasopharyngeal cancer for personalizing radiotherapy. A total of 37 weekly intravoxel incoherent motion DW-MRI studies were performed on 5 patients to assess early chemoradiation treatment response. The results demonstrated that chemoradiation treatment led to a decrease of tumor volumes in all 5 patients and an increase of diffusion and perfusion metrics in 4 patients. One patient had tumor infiltration of the muscle and the diffusion metric remained unchanged in this patient during treatment. The study concludes that diffusion and perfusion metrics are potential imaging biomarkers of tumor response.

3867.   60 The diagnostic performance of hybrid FDG-PET/MR compared to FDG-PET/CT in adult lymphoma patients
Alexander R Guimaraes1,2, Wendy Atkinson3, Ephraim Hochberg4, Jeremy Abramson5, Onofrio Catalano2, Bruce R Rosen2, and Ciprian Catana2
1Radiology, Oregon Health Sciences University, Portland, OR, United States, 2Radiology, Martinos Center for Biomedical imaging, Charlestown, MA, United States,3Radiology, Martinos Center for Biomedical imaging, Charlesown, MA, United States, 4Medicine, Massachusetts General Hospital, Boston, MA, United States,5Medicine, Massachusetts General Hospital, MA, United States

FDG-PET/CT has become an essential tool in the initial staging of Hodgkin lymphoma and aggressive non-Hodgkin lymphomas. In select histologies, early interim PET/CT has also shown to be a strong independent predictor of outcome. Hybrid PET/MR imaging is a novel imaging modality that offers improved soft tissue contrast, conspicuity of bone marrow infiltration, diffusion weighted imaging, and lower radiation dose: all factors that could have dramatic impact in the management of lymphoma. The overarching goal of this work was to test the hypothesis that PET/MRI offers an equivalent qualitative and quantitative imaging staging algorithm to PET/CT, but with decreased-risk of late radiation-associated toxicities.

3868.   61 Spontaneous R2* Fluctuations for Non-Invasive Detection of Cyclic Hypoxia in Head and Neck Squamous Cell Carcinoma Xenografts
Rafal Panek1, Lauren C.J. Baker2, Liam Welsh1, Carol Box2, Suzanne A. Eccles2, Kate L. Newbold1, Kevin J. Harrington1, Maria A. Schmidt1, Martin O. Leach1, and Simon P. Robinson2
1Royal Marsden NHS FT and Institute of Cancer Research, Sutton, Surrey, United Kingdom, 2Institute of Cancer Research, Sutton, Surrey, United Kingdom

The importance of acutely hypoxic tumour cells, resulting from intermittent tumour blood flow, on tumour progression and radioresistance is recognised. The potential of continuous intrinsic susceptibility MRI measurements of tumour R2* to non-invasively detect acute, cyclic hypoxia through changes in the oxy/deoxyhaemoglobin ratio has been previously demonstrated. In this study we have tested the feasibility of measuring spontaneous fluctuations in tumour R2* to identify regions with varying erythrocyte or plasma channels flow in head and neck squamous cell carcinoma xenografts on a clinical 3T platform. Additionally, hyperoxia-induced Capital Greek Delta R2* and tissue histology were used to spatially confirm hypoxic and perfused tumour regions.

3869.   62 Effects of Acquisition Time Variation on DCE-MRI Prediction of Breast Cancer Therapy Response
Andy J Kaempf1, Yiyi Chen1, Alina Tudorica1, Stephen Y-C Chui1, Arpana Naik1, Karen Y Oh1, Nicole Roy1, Megan L Troxell1, Aneela Afzal1, Megan L Holtorf1, Mohan Jayatilake1, and Wei Huang1
1Oregon Health & Science University, Portland, OR, United States

DCE-MRI data with ~10 min acquisition time were collected from 14 breast cancer patients (15 primary tumors) who received neoadjuvant chemotherapy (NACT). Data points were dropped incrementally from the far end of DCE time course to simulate ~9, 8, 7, and 6 min acquisition time. The original and simulated data were subjected to standard and shutter-speed model pharmacokinetic analyses. The results suggest 8 min acquisition time is needed to retain the Ktrans and kep abilities as early predictors of therapy response.

3870.   63 Effects of AIF Variations on DCE-MRI Prediction of Breast Cancer Therapy Response
Aneela Afzal1, Alina Tudorica1, Yiyi Chen1, Stephen Y-C Chui1, Arpana Naik1, Megan L Troxell1, Kathleen A Kemmer1, Karen Y Oh1, Nicole Roy1, Megan L Holtorf1, Xin Li1, and Wei Huang1
1Oregon Health & Science University, Portland, OR, United States

Breast DCE-MRI data from 29 patients at baseline and after one cycle of neoadjuvant chemotherapy were analyzed using pharmacokinetic (PK) modeling and three different arterial input functions (AIFs). Despite considerable AIF-caused PK parameter variations (except for the Tau_i parameter), several PK parameters after 1 cycle of therapy and their percent changes remained good to excellent early predictors of pathologic response.

Tuesday 2 June 2015
Exhibition Hall 16:00 - 17:00

  Computer #  
3871.   64 Using UTE images for bone/air segmentation: applications for radiation therapy - permission withheld
Weili Zheng1, Joshua P. Kim1, Indrin J. Chetty1, and Carri K. Glide-Hurst1
1Radiation Oncology, Henry Ford Health System, Detroit, Michigan, United States

Accurate bone segmentation is essential for the generation of (i) electron density maps needed for dose calculation in MR-only radiotherapy treatment planning (RTP) and (ii) MR-based attenuation correction maps in hybrid PET/MRI systems. While UTE sequences improve the visualization of tissues with short T2 such as cortical bone (1), efficient and robust segmentation of bone and air remains a significant challenge (2). To address this need, we introduce an application that uses a novel hybrid magnitude and phase UTE approach to differentiate tissue types, facilitate accurate segmentation, and generate synthetic CTs (synCTs) for the brain.

Tuesday 2 June 2015
Exhibition Hall 16:00 - 17:00

  Computer #  
3872.   65 Evaluating sources of uncertainty on DCE-MRI parameter estimates when using different AIFs
Mihaela Rata1, Matthew R Orton1, Christina Messiou1, Helen Young2, Nandita de Souza1, David J Collins1, and Martin O Leach1
1Radiotherapy and Imaging Department, CR-UK and EPSRC Cancer Imaging Centre, Institute of Cancer Research and Royal Marsden Hospital, Sutton, Surrey, United Kingdom, 2Early Clinical Development, AstraZeneca, Macclesfield, Cheshire, United Kingdom

Dynamic contrast-enhanced (DCE) MRI method is a technique employed in the assessment of tumour response to novel antiangiogenic therapy. Pharmacokinetic modelling of such data requires a reliable measure of the arterial input function (AIF) in order to obtain robust estimates of physiological parameters characterising tumour properties. This study explore the impact on Ktrans estimate of various sources of uncertainty affecting a MR-DCE acquisition. Three experiments were performed to separate sources of uncertainties. The best CoV of measured Ktrans is still obtained when using a population AIF. A perfect measure of AIF may yet improve a Ktrans repeatability up to 10%.

3873.   66 Classical and Knowledge-Based Pharmacokinetic Model Selection Techniques in Analysis of Dynamic Contrast Enhanced MRI Studies: Performance and Bias Comparison
Hassan Bagher-Ebadian1,2, Mohammadreza Mohammadian-Behbahani3,4, Azimeh Noorizadeh Vahed Dehkordi3,5, James R Ewing2,6, Alireza Kamali-Asl3, Siamak P Nejad-Davarani7, Hamed Moradi8, Stephen Brown2,9, Brent Griffith10, Ali S Arbab11, Tom Mikkelsen12, Lisa Scarpace12, and Hamid Soltanian-Zadeh1,13
1Radiology and Research Administration, Henry Ford Hospital, Detroit, Michigan, United States, 2Physics, Oakland University, Rochester, Michigan, United States,3Nuclear Engineering, Shahid Beheshti University, Tehran, Iran, 4Nuclear Engineering, Amir-Kabir University of Technology, Tehran, Iran, 5Nuclear Engineering, Najaf Abad Branch, Islamic Azad University, Isfahan, Iran, 6Neurology, Henry Ford Hospital, Detroit, Michigan, United States, 7Neurology, Henry Ford Hospital, Michigan, Iran, 8Nuclear Engineering, Shiraz University, Shiraz, Fars, Iran, 9Radiation Oncology, Henry Ford Hospital, Detroit, Michigan, United States,10Radiology, Henry Ford Hospital, Detroit, Michigan, United States, 11GRU Cancer Center, Georgia Regents University, Atlanta, Georgia, United States,12Neurosurgery, Henry Ford Hospital, Detroit, Michigan, United States, 13CIPCE, School of Electrical and Computer Engineering, University of Tehran, Tehran, Iran

Given Dynamic-Contrast-Enhanced MRI data, accurate estimation of Pharmacokinetic (PK) parameters strongly relies on appropriate selection of the best PK model to fit the data. This study investigates the impact of different classical and adaptive MS technique such as F-Statistic (F-test), Akaike-Information-Criterion (AIC), Bayesian-Information-Criterion (BIC), Log-Likelihood-Ratio (LLR) and Artificial Neural Network (ANN) on estimation of vascular permeability parameters. Results imply that ANN generates significantly less-biased estimates of PK parameters compared to other techniques while both the LLR and BIC methods outperform the other classical MS techniques, the ANN, LLR and BIC are the best candidates for PK analysis of DCE-MRI data.

3874.   67 Dynamic Contrast Enhanced Magnetic Resonance Imaging Evaluates Therapeutic Mechanism of nab-Paclitaxel in Pancreatic Cancer Patient Derived Xenograft Mouse Models.
Hyunki Kim1, Sharon Samuel1, Marie Warren1, Guihua Zhai1, William Grizzle1, Denise Oelschlager1, Pedro Lopez-Casas2, Manuel Hidalgo2, Joy Kovar3, Kurt Zinn1, and Donald Buchsbaum1
1University of Alabama at Birmingham, Birmingham, AL, United States, 2Spanish National Cancer Research Center, Madrid, Spain, 3LI-COR Biosciences, Nebraska, United States

Dynamic contrast enhanced magnetic resonance imaging (DCE-MRI) was employed to identify the therapeutic mechanism of nab-paclitaxel in pancreatic cancer patient derived xenograft mouse models. DCE-MRI demonstrated that nab-paclitaxel did not significantly increase the microvascular perfusion in tumor xenografts for 3 weeks of nab-paclitaxel treatment, although gemcitabine did. Also, histologic analysis showed that tumor stroma was not significantly reduced by nab-paclitaxel, but high tumor retention of fluorophore labeled nab-paclitaxel was observed. Therefore the significant clinical benefits of nab-paclitaxel may result from its effective delivery into tumors in pancreatic cancer.

3875.   68 Dynamic Contrast Enhanced MRI Detection of a Central Defect in Clear Cell Renal Cell Carcinoma Correlates with a Tumor Scar and Lower Tumor Proliferation Rate
Yue Zhang1, Payal Kapur2,3, Qing Yuan1, Ananth Madhuranthakam1,4, Ingrid Carvo5, Sabina Signoretti5, Ivan Dimitrov6, Yin Xi1, Katherine Wicks1, Jeffrey Cadeddu1,3, Vitaly Margulis3, James Brugarolas7,8, and Ivan Pedrosa1,4
1Radiology, University of Texas Southwestern Medical Center, Dallas, Texas, United States, 2Pathology, University of Texas Southwestern Medical Center, Dallas, Texas, United States, 3Urology, University of Texas Southwestern Medical Center, Dallas, Texas, United States, 4Advanced Imaging Research Center, University of Texas Southwestern Medical Center, Dallas, Texas, United States, 5Pathology, Brigham and Women’s Hospital, Boston, Massachusetts, United States, 6Philips Medical Systems, Cleveland, Ohio, United States, 7Internal Medicine, University of Texas Southwestern Medical Center, Dallas, Texas, United States,8Developmental Biology, University of Texas Southwestern Medical Center, Dallas, Texas, United States

The purpose was to investigate if the central non-enhancing defect seen commonly on contrast-enhanced MRI in clear cell renal cell carcinoma (ccRCC) correlates with coagulation necrosis at histopathology in the same tumor, a known poor prognostic feature for these tumors. We found that non-enhancing defects in ccRCC represent tumor scars instead of coagulative necrosis. Ki-67 staining revealed significantly lower cell proliferation rate for RCC with scar than that for those without scar. We hypothesize that this scar is the result of rapid enlargement of the tumor leading to a central infarct and may be formed during a subsequent reparative phase.

3876.   69 Measurements of Spontaneous R2* Fluctuations for Acute Hypoxia Detection in Head and Neck Cancer
Rafal Panek1, Liam Welsh1, Maria A. Schmidt1, Kate L. Newbold1, Kee Wong1, Angela M. Riddell1, Dow-Mu Koh1, Alex Dunlop1, Dualta Mcquaid1, Shreerang A. Bhide1, Kevin J. Harrington2, Christopher M. Nutting2, Georgina Hopkinson3, Cheryl Richardson3, Simon P. Robinson4, and Martin O. Leach1
1Royal Marsden NHS FT and Institute of Cancer Research, Sutton, Surrey, United Kingdom, 2Royal Marsden NHS FT and Institute of Cancer Research, London, United Kingdom, 3Royal Marsden NHS FT, London, United Kingdom, 4Institute of Cancer Research, Sutton, Surrey, United Kingdom

In this study we tested the feasibility of measuring spontaneous fluctuations in the transverse relaxation rate, R2*, to identify regions with intermittent erythrocyte and plasma flow, and hence oscillating oxygen delivery, in patients with advanced squamous cell carcinoma of the head and neck. Non-random fluctuations were detected in parts of lymph nodes with low Ktrans and R2* values, often in the vicinity, but not in the centre, of necrotic nodal core, suggesting the presence of fluctuating blood oxygen levels, which could be caused by an insufficient or intermittent blood delivery.

Tuesday 2 June 2015
Exhibition Hall 16:00 - 17:00

  Computer #  
3877.   70 Evaluation of Renal Masses using Multiparametric MRI: Correlation with Histopathology
Durgesh Kumar Dwivedi1,2, Girdhar Singh Bora3, Rajeev Kumar3, Sanjay Sharma4, Sanjay Thulkar4, Siddhartha Datta Gupta5, and Naranamangalam Raghunathan Jagannathan2
1Radiodiagnosis, King George's Medical University, Lucknow, U.P., India, 2NMR & MRI Facility, All India Institute of Medical Sciences, New Delhi, Delhi, India,3Urology, All India Institute of Medical Sciences, New Delhi, Delhi, India, 4Radiodiagnosis, All India Institute of Medical Sciences, New Delhi, Delhi, India,5Pathology, All India Institute of Medical Sciences, New Delhi, Delhi, India

RCC is a heterogeneous disease and therapy relies on accurate histologically subtype of tumors. mpMRI have shown its potential in diagnosing various malignancies. We studied RCC lesions using MRS and DW-MRI. MRS showed increased signal to noise ratio in mobile lipids in RCC and the resonance at 5.4 ppm was significantly higher in RCC. ADC was significantly decreased in RCC as compared to normal kidney. mpMRI could reliably differentiate malignant tissue from normal kidney parenchyma.

3878.   71 Multi-parametric whole body MRI in paediatric lymphoma; A comparison with reference standard PET-CT
Arash Latifoltojar1, Paul Humphries2, Stuart Taylor3, Ananth Shankar2, Stephen Daw2, and Shonit Punwani3
1University College London, London, London, United Kingdom, 2University College London Hospital, London, United Kingdom, 3University College London, London, United Kingdom

Positron emission tomography remains gold standard imaging for initial investigation and monitoring treatment response in paediatric lymphoma despite associated radiation exposure risk factors. Whole body MRI (WBMRI) provides a non-ionising alternative imaging modality for assessment of this group of patients. Anatomical and functional imaging such as diffusion weighted imaging can be implemented in WBMRI protocols for a comprehensive assessment of different aspects of suspected malignancy. In this work we investigated the diagnostic performance of whole body anatomical and functional imaging compared to reference standard PET-CT.

Tuesday 2 June 2015
Exhibition Hall 16:00 - 17:00

  Computer #  
3879.   73 Clinical Evaluation of TWIST DIXON Sequence with Flexible View Sharing for Breast DCE MRI: Can Initial Uptake Phase Provide Accurate Diagnosis
Yuan Le1, Hal D Kipfer1, Shadie S Majidi1, Brian Dale2, Marcel Dominik Nickel3, Randall Kroeker2, Elisabeth Weiland3, and Chen Lin1
1Radiology and Imaging Science, Indiana University School of Medicine, Indianapolis, IN, United States, 2Siemens Medical Solutions, NC, United States, 3Siemens Healthcare, Erlangen, Bavaria, Germany

A modified Time-resolved angiography With Stochastic Trajectories (TWIST) sequence with flexible view sharing and dual-echo DIXON was evaluated in clinical breast DCE-MRI for its capability of measuring initial uptake phase with fast acquisitions in addition to providing high resolution peak- and post-contrast images. A good correlation between the results based on the maximum slope of the signal enhancement in the initial phase and that based on the standard protocol was found, indicating a potential of shortening the breast MRI scan time and in turn a lowering of the breast MRI cost with this new technique.

3880.   74 Assessment of the correlation between ADC values and Oncotype DX score in estrogen-receptor positive, lymph node negative, breast cancers
Sunitha B Thakur1, Manuela Durando2, Milans Soledad3, Elizabeth J Sutton2, Dilip Giri2, and Elizabeth A Morris2
1Memorial Sloan Kettering Cancer Center, New York, NY, United States, 2Memorial Sloan Kettering Cancer Center, NY, United States, 3Memorial Sloan Kettering Cancer Center, New YORK, NY, United States

Preliminary studies have attempted to evaluate Apparent Diffusion Coefficient (ADC) values for its potential prognostic utility. However the impact of ADC on prognosis remains to be clearly defined. This study was conducted with the goal of determining whether there exists a correlation between ADC values and Oncotype Dx scores in estrogen-receptor positive and lymph node negative breast cancers. We found that mean ADC values were higher in Oncotype DX score stratified low risk cancers than in intermediate risk cancers. Our data at 3.0T MRI suggests that lower ADC values correlate with a higher Oncotype DX score and consequently, an increased risk of recurrence.

3881.   75 Multi-parametric Longitudinal Study for the Evaluation of Tumor Heterogeneity in Breast Cancer Patients Using Simultaneous MRSI & DWI Techniques
Naranamangalam R Jagannathan1, Khushbu Agarwal1, Uma Sharma1, Smriti Hari2, Vurthaluru Seenu3, and Rajinder Parshad3
1Department of NMR & MRI Facility, All India Institute of Medical Sciences, New Delhi, Delhi, India, 2Department of Radiodiagnosis, All India Institute of Medical Sciences, New Delhi, Delhi, India, 3Department of Surgical Disciplines, All India Institute of Medical Sciences, New Delhi, Delhi, India

ChoSNR and ADC were measured from same voxels in different breast tumor regions (solid tumor, necrosis and margin) prior to and after III NACT in 11 LABC patients (6 clinical responders and 5 non-responders). In responders, increased ChoSNR with decreased ADC of solid tumor was observed after therapy. ChoSNR decreased significantly with no ADC change at tumor margin. At necrosis no change in ChoSNR or ADC was seen. In non-responders ChoSNR and ADC did not change in tumor regions. Positive Pearson correlation between ChoSNR and ADC change signifies combined utility of both techniques simultaneously in therapeutic management of breast cancer.

3882.   76 Implementation of Multiparametric Magnetic Resonance Imaging with High-Resolution Dynamic Contrast-Enhanced and Diffusion-Weighted Magnetic Resonance Imaging at 7T Improves the Assessment of Breast Tumors: A Feasibility Study
Katja Pinker1, Pascal Baltzer1, Wolfgang Bogner2, Doris Leithner1, Siegfried Trattnig2, Olgica Zaric2, Peter Dubsky3, Rupert Bartsch4, Zsuzsanna Bago-Horvath3, Stephan Gruber2, Michael Weber1, and Thomas H Helbich1
1Dept. of Biomedical Imaging and Image-guided Therapy, Division of Molecular and Gender Imaging, Medical University of Vienna, Vienna, Austria, 2Dept. of Biomedical Imaging and Image-guided Therapy, MR Centre of Excellence, Medical University of Vienna, Vienna, Vienna, Austria, 3Dept. of Surgery, Medical University of Vienna, Vienna, Austria, 4Dept. of Internal Medicine, Division of Oncology, Medical University of Vienna, Vienna, Austria

The clinical use of multiparametric MR imaging at 7T is feasible with good or excellent image quality. Multiparametric MR imaging of the breast with DCE MR imaging and DWI at 7T seems to have the potential to diagnose breast cancer with high diagnostic accuracy (AUC 0.941). Multiparametric MR imaging of the breast with DCE MR imaging and DWI at 7T improves specificity as compared to interpretation of DCE MRI alone (p=0.031). Multiparametric MR imaging of the breast with DCE MR imaging and DWI at 7T can avoid unnecessary breast biopsies recommended with DCE MR imaging, in our series in 6/8 (75%, p=0.031) of benign breast tumors.

3883.   77 Registration of Multiparametic Breast MRI
Lawrence Kenning1, Martin Pickles1, and Lindsay Turnbull1
1Centre for MR Investigations, Hull York Medical School at University of Hull, Hull, United Kingdom

Motion during breast MR examination can degrade DCE data and cause spatial mismatches between sequences. Data acquired from 19 patients was retrospectively corrected using rigid and non-rigid schemes. For the DCE series, mean coefficients of variation were found to be 45.2±3.9%, 40.0±3.1% and 35.7±2.5% for the original data, rigid motion corrected data and the non-rigid motion corrected data. Non-rigid registration between MR series was successfully applied to all patients and showed good visual agreement. The global 4D registration methodology enables researchers and clinicians to contour single volume of interests that can be used to simultaneously interrogate multiple breast MR series.

3884.   78 Multi-parametric MRI in evaluating pre-and post-menopausal ER positive breast cancer
Elizabeth O'Flynn1, David Collins1, James D'Arcy1, Maria Schmidt1, and Nandita deSouza1
1CRUK Cancer Imaging Centre, The Institute of Cancer Research, Sutton, Surrey, United Kingdom

The purpose of this study was to compare multiparametric MRI parameters of ER positive tumours in pre- and postmenopausal women to assess any differences in tumour functional characteristics and to establish which parameter correlated significantly with response as defined by tumor volume reduction.In premenopausal women with ER positive breast cancer, tumors were larger and more vascular than in postmenopausal women. A rise in the ve correlated significantly with volume reduction in premenopausal women; no specific parameter correlated with response in postmenopausal women.

3885.   79 Assessment of Pathologic Complete Response of Breast Cancer with Different Molecular Subtypes after Neoadjuvant Chemotherapy with Dynamic Contrast-enhanced MR Imaging
Yuan Jiang1, Naishan Qin1, Xiaoying Wang1, and Li Guo1
1Radiology Department, Peking University First Hospital, Beijing, Beijing, China

Different molecular subtypes of breast cancer respond differently to neoadjuvant chemotherapy. Patients who achieve pathologic complete response (pCR) have better prognosis than non-pCR. In our study, semi-quantitative analysis of dynamic contrast-enhanced (DCE) MR Imaging between pCR and non-pCR was performed in four types of breast cancer (Luminal A, Luminal B, HER2+ and Triples negative), and our results showed that DCE-MR Imaging could become the potential predictor of pCR to NAC in breast cancer with Luminal B and Triples negative types. Maybe further study should be performed based on molecular subtypes of breast cancer.

3886.   80 Optimization of Quantitative MRI Background Parenchymal Enhancement Metrics to Predict Breast Cancer Risk
Cheng-Liang Liu1, Savannah C Partridge1, Diana L Lam1, Constance D Lehman1, and Habib Rahbar1
1Department of Radiology, University of Washington, Seattle, Washington, United States

Background parenchymal enhancement (BPE) on MRI has been proposed to be a biomarker of breast cancer risk. We sought to develop an optimal method to measure BPE quantitatively for breast cancer risk assessment. By measuring various BPE metrics at enhancement thresholds ranging from 5-100% in a case-control (n=36), we found that quantitative BPE measures are higher in women who developed breast cancer than in controls, with a 70% enhancement threshold for BPE area providing the highest accuracy for predicting risk. Our findings suggest quantitative BPE measures can assess breast cancer risk, potentially allowing individualized screening and prevention strategies.

3887.   81 Clinical Utility of Sequential DWI in Studying Tumor Margins as an aid to Breast Conservation Surgery
Naranamangalam R Jagannathan1, Khushbu Agarwal1, Rani G Sah1, Uma Sharma1, Smriti Hari2, Vurthaluru Seenu3, and Rajinder Parshad3
1Department of NMR & MRI Facility, All India Institute of Medical Sciences, New Delhi, Delhi, India, 2Department of Radiodiagnosis, All India Institute of Medical Sciences, New Delhi, Delhi, India, 3Department of Surgical Disciplines, All India Institute of Medical Sciences, New Delhi, Delhi, India

ADC were measured at whole tumor (WT), and from five geographical zones from inside tumor margin (IM) in a layerwise manner to outside tumor margin III (OM1, OM2, OM3) and intra-tumoral necrotic domains (Nec) sequentially i.e., prior to (Tp0), after I (Tp1) and III (Tp3) neoadjuvant chemotherapy (NACT) in 36 breast cancer patients. A significant increase in ADC was seen for WT and IM, while it decreased at OM1 compared to OM2 and OM3 at Tp3. The change in ADC of WT and nec after therapy showed positive Pearson correlation. Results indicated the utility of DWI in breast conservation surgery.

3888.   82 Evaluation of the Efficiency of DTI Anisotropy Indices to Detect Breast Cancer
Edna Furman-Haran1, Dov Grobgeld2, Noam Nissan2, Myra Feinberg-Shapiro3, Tania Zehavi3, Zvi Kaufman3, and Hadassa Degani2
1Department of Biological Services, The Weizmann Institute of Science, Rehovot, Israel, 2Department of Biological Regulation, The Weizmann Institute of Science, Rehovot, Israel, 3Meir Medical Center, Kfar Saba, Israel

DTI tracks the water diffusion in different directions and thereby allows characterizing breast microstructures with restricted diffusion, revealing their organization in vector/ellipsoid-maps and parametric-maps of anisotropy-indices, derived from the diffusion tensor eigenvectors and eigenvalues, respectively. The study evaluates of the various anisotropy-indices investigating their ability to detect breast cancer. The results indicate that the commonly used normalized anisotropy-indices fail to differentiate cancer from normal tissue, while the un-normalized maximal anisotropy index is significantly lower in cancer as compared to normal tissue and can be efficiently used for detecting breast cancer in conjunction with the reduction in the diffusion coefficients.

3889.   83 A Preliminary Study of Diffusion Kurtosis Imaging for Assessment of Breast Lesions
Shiteng Suo1, Fang Cheng1, He Wang2, Jia Hua1, and Jianrong Xu1
1Department of Radiology, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China, China, 2Philips Research Chinia, Shanghai, China, China

In the study, the preliminary results showed that the water diffusion followed a non-Gaussian behavior by using diffusion kurtosis imaging (DKI) in breast lesions. The malignant tumors tended to have a restricted diffusion pattern and an increased K value compared to fibroadenoma. With the capability to quantify the deviation from Gaussian distribution, the K value may give insight into the microstructure complexity in vivo.

3890.   84 Improved Diagnostic Performance of 3T Breast MRI using Perfusion-Adjusted ADC Values
Niloufar Fozouni1, Cheng-Liang Liu1, Habib Rahbar1, Constance D Lehman1, and Savannah C Partridge1
1Department of Radiology, University of Washington, Seattle, Washington, United States

Diffusion-weighted imaging (DWI) holds potential for reducing false positives on conventional breast MRI based on differences in apparent diffusion coefficient (ADC) values between benign and malignant lesions. However, standard DWI approaches can result in ADC values strongly influenced by perfusion, potentially increasing overlap in ADC between pathologies. In this study, we found that separation of perfusion and diffusion-weighted components of lesion ADC measures using a simplified approach can improve diagnostic performance. Furthermore, we found that a multiparametric combination of DWI and DCE features can provide more accurate assessment of suspicious MRI-detected breast lesions.

3891.   85 Intravoxel incoherent motion MRI may reveal microvascular variation of fibroglandular tissues in breast cancer
Jing Yuan1, Gladys G. Lo2, Oi Lei Wong1, Helen H.L. Chan2, Abby Y. Ding1, Ting Ting Wong3, and Polly S.Y. Cheung3
1Medical Physics and Research Department, Hong Kong Sanatorium & Hospital, Happy Valley, Hong Kong, China, 2Department of Diagnostic & Interventional Radiology, Hong Kong Sanatorium & Hospital, Happy Valley, Hong Kong, China, 3Breast Care Center, Hong Kong Sanatorium & Hospital, Happy Valley, Hong Kong, China

This study aims to investigate the micro-vascularity of fibroglandular tissues (FGTs) in breast cancer (BC) using intravoxel incoherent motion (IVIM) MRI. 21 histology-confirmed patients received IVIM-MRI at 3T. True diffusion D, pseudo-diffusion D*, pseudo-diffusion fraction f and ADC in ipsilateral and contralateral breast FGTs were compared. Results show that FGT D* and f in the ipsilateral tumor-bearing breast were higher than those in the contralateral breast (D*: 24.96ˇÓ9.37ˇŃ10-3mm2/s v.s. 19.98ˇÓ9.37ˇŃ10-3mm2/s; f: 0.123ˇÓ0.034 v.s. 0.109ˇÓ0.030), with D* being significant (p=0.033). FGT microvascular variation revealed by IVIM-MRI may potentially be used for breast cancer risk assessment, characterization and/or prognosis

3892.   86 Intralesional Characteristics of Correlated 18-Fluorodeoxyglucose PET and Intravoxel Incoherent Motion Parameters in Locally Advanced Breast Cancer
Jason Ostenson1, Linda Moy1, Sungheon G. Kim1, Amy Melsaether1, Komal Jhaveri2, Christian Geppert3, David Faul3, Francisco Esteva2, Sylvia Adams2, Freya Schnabel4, Kimberly Jackson1, Joon Lee1, Christopher Glielmi3, Gene Young Cho1,5, Thorsten Feiweier6, and Eric E. Sigmund1
1Department of Radiology, NYU Langone Medical Center, New York, NY, United States, 2Perlmutter Cancer Center, NYU Langone Medical Center, New York, NY, United States, 3Siemens Medical Solutions, New York, NY, United States, 4Department of Surgery, NYU Langone Medical Center, New York, NY, United States,5Sackler Institute of Graduate Biomedical Sciences, NYU School of Medicine, New York, NY, United States, 6Siemens AG, Erlangen, Germany

Simultaneously acquired diffusion weighted imaging and 18-fluorodeoxyglucose(FDG)-PET are employed to explore the relationship between glucose avidity, diffusion, and perfusion in breast cancer. Intravoxel incoherent motion metrics are calculated and combined with correlated FDG-PET standard uptake values (SUV) for all voxels in 16 histopathologically proven breast cancer lesions. Two-dimensional histograms and Pearson’s correlations are used to define three lesion types. Each lesion’s voxels are separated into three groups according to their SUV, diffusion, and perfusion fraction. The results yield insight into the heterogeneity of the tumor microenvironment and show significant correlations with estrogen receptor expression and a cellular proliferation marker (Ki-67).

3893.   87 Initial results of the Application of a Modified TWIST Sequence with Flexible View Sharing in Breast DCE-MRI
Yuan Le1, Hal D Kipfer1, Marcel Dominik Nickel2, Randall Kroeker3, Stephanie P Holz1, Elisabeth Weiland2, and Chen Lin1
1Radiology and Imaging Science, Indiana University School of Medicine, Indianapolis, IN, United States, 2Siemens Healthcare, Erlangen, Bavaria, Germany,3Siemens Medical Solutions, NC, United States

Time-resolved angiography With Stochastic Trajectories (TWIST) Sequence was modified with flexible TWIST view sharing and flexible echo time Dixon for the acquisition of images with high and flexible spatial and temporal resolution as well as uniform fat suppression. Our initial experience shows that it provides potentially valuable information on early tumor enhancement characteristics while maintaining excellent image quality at post-contrast enhancement in breast DCE-MRI, allowing more optimized spatial and temporal resolution in clinical breast imaging.

Tuesday 2 June 2015
Exhibition Hall 16:00 - 17:00

  Computer #  
3894.   88 2HG Metabolic Profiling Analysis based on 13C-NMR Spectroscopy with Stable13C-labeled Isotope - permission withheld
Hyeon-Man Baek1,2, Youngjae Jeon1, Jooyun Kim1, and Mirim Bang1
1Center for MR Research, Korea Basic Science Institute, Ochang, Chungbuk, Korea, 2Department of Bio-Analytical Science, University of Science & Technology, Daejeon, Chungnam, Korea

The aim of this study was two-fold: first, to investigate the metabolic profiling analysis based on 13C-NMR spectroscopy with stable 13C-labeled isotope, and second, to demonstrate whether 2HG labeling from [U-13C]glucose substrate feeding could be detected in IDH1 or 2 mutated cells.The analysis of 1H- and 13C-NMR spectra of the cell extracts showed a significant increase in the concentration of the 2HG in IDH mutated cells, but not in IDH wild type and mutant IDH cells with low transfection efficiency.

3895.   89 Evaluation of PET/MR and DWI in malignant lymphoma: initial results in 17 patients
Chiara Giraudo1, Michael Weber1, Markus Raderer2, Georgios Karanikas1, and Marius Erik Mayerhoefer1
1Departments of Biomedical Imaging and Image-guided Therapy, Medical University of Vienna, Vienna, Austria, 2Internal Medicine I, Medical University of Vienna, Vienna, Austria

This study was performed to assess the diagnostic value of PET/MR and DWI in the evaluation of nodal and extranodal lymphoma. PET/MR is an emerging hybrid technique that has already demonstrated very good results for the diagnosis of malignancies in different anatomical districts but up to now, only few data are available in the literature about its application on patients affected by lymphoma. Our initial results demonstrated that, for both nodal and extranodal disease, PET/MR is a highly promising technique and DWI confirmed to be an essential tool to improve the diagnostic work-up of this heterogeneous cancer group.

3896.   90 Automated Planning of Scan Geometry in Follow-up Prostate MRI Examinations
Peter Mazurkewitz1, Daniel Bystrov1, Peter Koken1, Torbjoern Vik1, and Julien Sénégas1
1Philips Research Laboratories, Hamburg, Germany

In this work, we present a robust and accurate method for the automated planning of scan geometry in follow-up prostate exams. In order to better cope with the specific challenges of prostate MR exams, where high-resolution scans with small FOV generally need to be planned, the rigid registration method presented recently was adapted by using an image based organ detection as initialization of the registration algorithm. This step ensures a robust and stable registration. This new approach was evaluated retrospectively on volunteer data and tested on a commercial MRI system.

3897.   91 DCE-MRI of prostate cancer: perfusion quantification with Tofts model vs. shutter-speed model. Initial experience.
Cecilia Besa1, Guido Jajamovich2, Adnan Ali3, Wei Huang4, Kenneth Haines5, Ash Tewari3, and Bachir Taouli6
1Radiology, Icahn School of Medicine at Mount Sinai, New York, NY, United States, 2icahn School of Medicine at Mount Sinai, NY, United States, 3Urology, Icahn School of Medicine at Mount Sinai, NY, United States, 4Radiology, Oregon Health & Science University, Portland, OR, United States, 5Pathology, Icahn School of Medicine at Mount Sinai, NY, United States, 6Icahn School of Medicine at Mount Sinai, New York, NY, United States

Synopsis: The purpose of this study was to evaluate the value of quantitative diffusion weighted imaging (DWI) and dynamic contrast enhanced (CE) MRI in predicting histopathologic characteristics of liver metastatic neuroendocrine tumors (NET). We found that neuroendocrine carcinoma (G3) liver metastases had significantly lower ADC values and higher arterial enhancement rate (ER) than Grade 1 and 2 NETs. In addition, significant negative correlation was observed between ADC and ER and mitotic count and Ki-67% labeling index. DWI with ADC quantification and CE-MRI may be useful for predicting tumor grade in metastatic hepatic NET.

3898.   92 The Effect of Groupwise Elastic Registration in Discrimination of Benign and Malignant Ovarian Cancers by Pharmacokinetic Parameters
Elaheh Kia1,2, Anahita Fathi Kazerooni1,2, Saeedeh Navaei Lavasani1,2, Alireza Ahmadian2, and Hamidreza Saligheh Rad1,2
1Quantitative MR Imaging and Spectroscopy Group, Research Center for Molecular and Cellular Imaging, Tehran University of Medical Sciences, Tehran, Iran,2Department of Medical Physics and Biomedical Engineering, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran

Dynamic contrast enhanced MRI (DCE-MRI) has shown to be promising for quantitative assessment of complex ovarian cancers. Quantification of DCE-MR images could be affected by motion artifacts and intensity inhomogeneity induced by bias fields. Proper selection of a registration algorithm could impact the outcome of this problem. In this work, we proposed an efficient non-rigid registration method in a group-wise setting to non-rigidly align DCE-MR images to reliable quantification of ovarian masses.