Shigeki Nagamachi MD, PhD, Presenter: Nothing to Disclose

Ryuichi Nishii MD, PhD, Abstract Co-Author: Nothing to Disclose

Youichi Mizutani, Abstract Co-Author: Nothing to Disclose

Tatefumi Sakae MD, Abstract Co-Author: Nothing to Disclose

Eiji Furukoji MD, PhD, Abstract Co-Author: Nothing to Disclose

Hideyuki Wakamatsu MD, Abstract Co-Author: Nothing to Disclose

Shozo Tamura MD, PhD, Abstract Co-Author: Nothing to Disclose

Diagnosis of biliary cancer using F-18 FDG PET/CT is sometimes difficult because of existence of FDG-negative cancer and some overlaps between FDG-positive benign and malignant lesions. Because of MRI's superiority in high tissue contrast resolution, the evaluation of boundary between biliary cancer and surrounding tissues may be suitable.  We compared the diagnostic ability of differentiating biliary lesions between F-18 FDG PET/MRI fusion image and PET/CT. In addition, we evaluated additional information obtained by F-18 FDG PET/MRI fusion image in diagnosing biliary cancer.  

Forty-seven biliary malignant tumors and 11 benign lesions were investigated. The image fusions were done retrospectively by F-18 FDG-PET and MRI T1,T2-weighted images on workstation. We calculated diagnostic ability (sensitivity, specificity, PPV, NPV and accuracy) for differential diagnosis and compared them between F-18 FDG PET/MRI and PET/CT. In addition, we analyzed additional information of F-18 FDG PET/MRI fusion images.

F-18 FDG PET/MRI fusion image showed better diagnostic capability compared with that of PET/CT in the differential diagnosis ( Table 1). FDG negative cancers were detected as high intensity lesions on MRI T2-weighted image. FDG positive inflammation was correctly diagnosed by MRI’s anatomical interpretation. As additional information, vessel invasion, dilatation of upper side bile-duct and cancer invasion along bile-duct were observed in almost one-third of cases by F-18 FDG PET/MRI -T2 fusion images.

F-18 FDG PET/MRI fusion image was more useful than PET/CT in differentiating biliary cancer from benign lesion and in evaluating cancer invasion to surrounding or internal tissues.

In differentiating biliary cancer from benign lesions, F-18 FDG PET/MRI fusion image is recommended as first choice.

Nagamachi, S, Nishii, R, Mizutani, Y, Sakae, T, Furukoji, E, Wakamatsu, H, Tamura, S, The Usefulness of F-18 FDG PET/MRI Fusion Images in Diagnosing Biliary Lesions.  Radiological Society of North America 2014 Scientific Assembly and Annual Meeting, - ,Chicago IL. http://archive.rsna.org/2014/14045644.html