Positron emission tomography (PET) with fluorodeoxyglucose F18 (18 F-FDG) is useful for detecting malignancies, but benign lesions occasionally have false-positive 18 F-FDG uptake. Here, we report the cases of five postmenopausal women with solid ovarian tumors suspected to be ovarian cancer on magnetic resonance imaging and 18 F-FDG uptake. Mean age of the five patients was 57 years (range, 53-65 years). Average early standardized uptake value (SUV) of 18 F-FDG was 5.76 (range, 2.2-12.0) and delayed SUV was 6.56 (range, 2.4-13.8). In all five patients, frozen section diagnosis at surgery was thecoma, and bilateral salpingo-oophorectomy was performed. On immunohistochemistry, immunoreactive glucose transporter 5 (GLUT5) expression was detected in thecoma tissues. This case shows that thecoma sometimes has positive 18 F-FDG uptake on positron emission tomography-computed tomography (PET-CT), indicating the need for caution regarding false-positive PET-CT in patients with benign solid ovarian tumor.
Keywords: glucose transporter 5; positron emission tomography-computed tomography; thecoma.
© 2016 Japan Society of Obstetrics and Gynecology.