Murat Alp Oztek^1,2, Stephen R Bowen², Savannah C Partridge¹, Daniel S Hippe¹, William T. Yuh¹, Aaron S Nelson³, Simon S Lo², Elaine Y Lee⁴, Eric Leung⁵, John C Grecula⁶, Matthew Harkenrider⁷, Michael V Knopp⁶, Wei Wu¹, and Nina A Mayr^2
1Radiology, University of Washington, Seattle, WA, United States, ²Radiation Oncology, University of Washington, Seattle, WA, United States, ³MIM Software, Beachwood, OH, United States, ⁴Radiology, The University of Hong Kong, Hong Kong, Hong Kong, ⁵Sunnybrook Health Sciences Centre, University of Toronto, Toronto, ON, Canada, ⁶Ohio State University, Columbus, OH, United States, ⁷Loyola University, Chicago, IL, United States

DCE, ADC and ¹⁸FDG PET/CT radiomics parameters, obtained simultaneously before, early during and midway during ongoing radiation/chemotherapy correlate with tumor response and particularly mortality, and can serve as early predictors of treatment outcome in advanced cervical cancer.  Longitudinal development of functional heterogeneity may be a sensitive measure reflecting responsiveness of individual tumors to a specific cytotoxic treatment regimen.  Particularly the persistence of skewness of the dynamic contrast enhancement within the tumor volume predicted cancer mortality.  Functional radiomics assessment may help address the unmet need for a patient- and treatment-specific early indicator of tumor responsiveness and survival. 

Rakesh Shiradkar¹, Ruyuan Zuo¹, Amr Mahran², Lin Li¹, Britt Conroy^2,3, Lee Ponsky^2,3, Sree Harsha Tirumani^2,3, and Anant Madabhushi^1
1Case Western Reserve University, Cleveland, OH, United States, ²UH Cleveland Medical Center, Cleveland, OH, United States, ³Case Western Reserve University School of Medicine, Cleveland, OH, United States

Serial MRI allows for non-invasive monitoring of prostate cancer patients on Active Surveillance (AS). However, repeat biopsies continue to be defacto standard for AS monitoring due to limitations of MRI. In this study, we sought to compute delta changes in radiomic features on serial bi-parametric MRI and evaluate their associations with biopsy upgrading. We observed that delta radiomic features that quantify underlying spatial, gradient based heterogeneity were associated with biopsy upgrading. On univariable and multivariable analysis with routine clinical variables, we observed that none of the clinical variables were significant while delta radiomic classifier predictions were significant and independently predictive.

Chongpeng Sun^1,2, Shiyang Wang^1,3, Aritrick Chatterjee¹, Milica Medved¹, Scott Eggener⁴, Gregory S Karczmar¹, and Aytekin Oto^1
1Radiology, University of Chicago, Chicago, IL, United States, ²Radiology, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, China, ³Medical Physics, University of Missouri, Columbia, MO, United States, ⁴Urology, University of Chicago, Chicago, IL, United States

This study evaluated the utility of T2*-weighted (T2*W) MRI for intra-operative identification of ablation zone extent during focal laser ablation (FLA) of prostate cancer. Ablation zone ROI sizes and contrast-to-background ratio (CBR) were calculated on T2*W and apparent diffusion coefficient (ADC) maps and compared to those in the reference standard subtracted contrast-enhanced T1-weighted (sceT1W) images. CBRs on T2*W (TE=32,63 ms) did not differ significantly from those in sceT1W, and ROI sizes in T2*W (TE=63 ms) and sceT1W were well-correlated and differed by only 15%. Therefore, T2*W MRI with long TE visualizes post-procedure ablation zone comparably to contrast-enhanced T1W MRI.

Gabriel Addio Nketiah¹, Léo Pallas², Adrian L Breto ³, Radka Stoyanova³, Mattijs Elschot ¹, and Tone F. Bathen^1,4
1Circulation and Medical Imaging, Norwegian University of Science and Technology, Trondheim, Norway, ²Department of Digital Science, CPE Lyon, Lyon, Norway, ³Sylvester Comprehensive Cancer Center, University of Miami, Miami, FL, United States, ⁴Clinic of Radiology and Nuclear Medicine, St. Olavs University Hospital, Trondheim, Norway

The utility of multiparametric (mp) versus biparametric (bp) MRI protocol in prostate cancer diagnosis has been compared in several large studies, but mainly using manual qualitative evaluation. In this study we employed machine learning models to investigate the added value of DCE (i.e. mpMRI) in predicting significant cancer foci in pre-biopsy MR images. Whereas both protocols had comparable results in the whole prostate and transition zone analyses, we found mpMRI model to be more useful in the peripheral zone, where significant differences (p < 0.05) were found for all performance measures i.e. area under the curve, accuracy, sensitivity and specificity. 

Jeremiah W Sanders¹, Steven J Frank², Aradhana M Venkatesan³, Tharakeswara K Bathala³, Chad Tang², Rajat J Kudchadker⁴, Teresa L Bruno², Mark D Pagel⁵, and Jingfei Ma^1
1Imaging Physics, University of Texas MD Anderson Cancer Center, Houston, TX, United States, ²Radiation Oncology, University of Texas MD Anderson Cancer Center, Houston, TX, United States, ³Diagnostic Radiology, University of Texas MD Anderson Cancer Center, Houston, TX, United States, ⁴Radiation Physics, University of Texas MD Anderson Cancer Center, Houston, TX, United States, ⁵Cancer Systems Imaging, University of Texas MD Anderson Cancer Center, Houston, TX, United States

Parallel imaging and compressed sensing (PICS) techniques have demonstrated the ability to accelerate MRI acquisitions in a number of clinical MRI protocols. For postimplant prostate brachytherapy MRI, an endorectal coil (ERC) is currently used to achieve images of sufficient signal-to-noise ratio (SNR) for postimplant quality assessment. Previously we retrospectively demonstrated the feasibility of using PICS to accelerate postimplant prostate brachytherapy MRI. In this work, we prospectively demonstrate that combining PICS with fully balanced steady-state free precession MRI enables high resolution and high SNR images of the prostate without an ERC.

Aritrick Chatterjee¹, Xiaobing Fan¹, Ambereen Yousuf¹, Tatjana Antic², Gregory Karczmar¹, and Aytekin Oto^1
1Department of Radiology, University of Chicago, Chicago, IL, United States, ²Department of Pathology, University of Chicago, Chicago, IL, United States

This study investigates whether quantitative MRI of the prostate reveals differences between ethnicities that can affect diagnosis. This study shows that the different ethnicities, specifically AAs and CAs have different quantitative MRI values that affects the utility of MRI in the diagnosis of PCa. Different thresholds are needed for PCa diagnosis for different ethnicities. Despite more high grade lesions in AA, the ADC and T2 for lesions in AA were nominally higher than in CA. DCE-MRI significantly improves differentiation of PCa from benign tissue in AA, due to significantly higher cancer signal enhancement rate in AA compared to CA.

Lan Zhang¹, Xin Li¹, Ping Han¹, and Fan Yang^1
1Radiology, Union Hospital, Tongji Medical College,Huazhong University of Science and Technology, Wuhan, China

 We speculate that APT value may be a useful biomarker for assessing rectal pathological characteristics, which could have a potential impact on the clinical therapeutic strategies for patients. We have established a baseline for the APT values in rectal cancer, which was shown significantly correlated with pathologic features (eg. tumor grade and Ki-67 index).

Ling Li¹, Yingjie Mei², Zhaoxian Yan³, Jieping Feng³, Bo Liu³, and Xian Liu^3
1Guangzhou University of Chinese Medicine; The second Affiliated hospital of Guangzhou University of Chinese Medicine;, Guangzhou, China, ²Clinical Science,Philips Healthcare;, Shanghai, China, ³Radiology, The second Affiliated hospital of Guangzhou University of Chinese Medicine, Guangzhou, China

The Accurate preoperative staging and grading are significant on the treatment of protocol selection rectal adenocarcinoma. As a new molecular MR imaging technique, APT imaging could provide information that correlates with tumor cell proliferation. In this study, the capability of APT in differentiating WHO grades and pathologic stages of rectal adenocarcinoma was investigated and compared with DWI. The results show that APT value have a significantly positive correlation with the stage and grade of the rectal adenocarcinoma, and the prognosis factor Ki67.

Xiangchun Liu¹, Yu Fu¹, Yan Guo², Kan He¹, Qi Yang¹, and Huimao Zhang^1
1The First Hospital of Jilin University, changchun, China, ²GE Healthcare, beijing, China

Perineural invasion (PNI), defined by tumor invasion of nervous structures and nerve sheaths, which is thought an independent predictor of outcome in rectal cancer. However, for a radiologist, neither MRI nor CT can reliably evaluate PNI. Radiomics is an emerging and effective method for quantitative analysis and prediction using big data of medical imaging. Therefore, this study aims to develop and validate a radiomics prediction model based on MRI and CT for the preoperative prediction of PNI in rectal cancer. The results indicated that excellent diagnostic performance can be yielded with such multi-modal radiomics.

Li Zhao¹, Hongmei Zhang¹, Lizhi Xie ², and Xinming Zhao^1
1Diagnostic Radiology, Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China, ²MR Research, GE Healthcare, Beijing, China

The aim of this study was to evaluate the feasibility of quantitative synthetic magnetic resonance imaging (SyMRI)-derived histogram of the primary tumor for predicting the regional lymph node (LN) metastasis in patients with rectal cancer (RC). Our study indicated that histogram parameters of primary tumor on T1 mapping and T2 mapping were associated with regional LN status in RC. Moreover, the combination of the quantitative SyMRI parameters, pathological extramural venous invasion (EMVI), and maximum tumor diameter may significantly improve the predictive performance of LN metastasis.

Yongjian Zhu¹, Ying Li¹, Jun Jiang¹, Yutao Zhou¹, Liming Jiang¹, Liyan Xue², and Lizhi Xie^3
1Department of Imaging Diagnosis, National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China, ²Department of Pathology, National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China, ³GE healthcare, China, Beijing, China

Extramural vascular invasion (EMVI) has been found as an independent risk factor for recurrence and distant metastasis in patients with gastric cancer. Dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) and diffusion weighted imaging (DWI) has been applied in diagnosis of different cancers. In this study, we research into the value of DCE-MRI parameters and ADC in predicting EMVI and the prognostic significant. It was found that K^trans, V_e and ADC are independent predictors of pathological EMVI in LAGC, and MRI-predicted EMVI (mrEMVI) confirmed to be a poor prognosis predictor in terms of 2-year recurrence-free survival (RFS).

Alexandra W. Acher¹, TJ Colgan¹, Yuxin Zhang¹, Krisztian Kovacs², Jitka Starekova¹, Victoria Rendell³, Daniel E. Abbott³, Erin Brooks², Rashmi Agni², Emily Winslow⁴, and Scott B. Reeder^5
1Department of Radiology, University of Wisconsin, Madison, WI, United States, ²Department of Pathology, University of Wisconsin, Madison, WI, United States, ³Department of Surgery, University of Wisconsin, Madison, WI, United States, ⁴Department of Surgery, Georgetown University, Washington DC, MD, United States, ⁵Department of Radiology and Department of Medical Physics, University of Wisconsin, Madison, WI, United States

The purpose of this study was to develop a protocol for use of a previously validated radiologic-histologic correlation device to evaluate the pancreas with ex vivo MRI. Precise radiologic-histologic correlation of pancreatic anatomy was achieved in cadaveric pancreas specimens. The final protocol will be applied to co-localize pancreas cancer margins radiologically and histologically, as well as nodal burden in pancreaticoduodenectomy specimens.

Yoshiharu Ohno^1,2, Masao Yui³, Daisuke Takenaka⁴, Yoshimori Kassai³, Kazuhiro Murayama¹, and Takeshi Yoshikawa^2
1Radiology, Fujita Health University School of Medicine, Toyoake, Japan, ²Radiology, Kobe University Graduate School of Medicine, Kobe, Japan, ³Canon Medical Systems Corporation, Otawara, Japan, ⁴Diagnostic Radiology, Hyogo Cancer Center, Akashi, Japan

No report has been found to compare the capability of pulmonary MR imaging with UTE for nodule detection and Lung-RADS classification as compared with low-dose CT (LDCT) and standard-dose CT (SDCT).  We hypothesized that pulmonary MR imaging with UTE has a similar potential to detect pulmonary nodules and evaluate Lung-RADS classification as well as LDCT and SDCT.  The purpose of this study was to compare the capability of pulmonary MR imaging with UTE for lung nodule detection and evaluation of Lung-RADS classification with LDCT and SDCT. 

Nan Zhang¹, Qingwei Song¹, Lina Zhang¹, Ailian Liu¹, Haonan Zhang¹, Yu Song¹, Liangjie Lin², Jiazheng Wang², and Zhiwei Shen^2
1The First Affiliated Hospital of Dalian Medical University, Dalian, China, ²Philips Healthcare, Beijing, China

Amide proton transfer (APT) imaging is based on the chemical exchange between free bulk water protons and the amide protons (-NH) of endogenous mobile proteins and peptides in tissue. Previous studies have shown that APT-weighted (APTw) MRI could noninvasively identify and differentiate tumors in brain, head and neck etc. This study aims to explore the feasibility of APTw-MRI in characteristics and discrimination of premenopausal malignant and benign breast tumors.The results show that the APTw MR imaging efficiency of diagnosis of premenopausal breast tumors were 0.904.