Clinical Significance of Incidental FDG Uptake in the Prostate Gland Detected by PET/CT

1452 Objectives It is known that 18F-fluorodeoxyglucose (FDG) uptake in prostate cancer is varying degrees, but the value of FDG positron emission tomography/computed tomography (PET/CT) for detecting prostate cancer is unknown. We aimed that investigate the clinical value of incidental prostate FDG uptake on PET/CT scan. Methods We reviewed 6128 male patients who underwent FDG-PET/CT scans from 2007 to 2014 and selected cases that reported hypermetabolic lesions in the prostate gland. The patients who have prior history of prostate carcinoma or prostate surgery were excluded from study. We have analyzed the correlation between PET/CT findings and serum prostate-specific antigen (PSA) levels, imaging studies (USG), urological examinations and biopsy. Results Incidental FDG uptake of the prostate gland was observed in 79 patients (1.3 %). 16 patients were excluded due to inadequate clinical data, 63 patients were included for further analysis. Prostate biopsies were performed in 12 patients, and prostate cancer was diagnosed in 8 of them. In 51 patients that have normal serum PSA levels, were considered to be no malignancy in the prostate gland. The patients were divided into two groups as malignant and benign. The mean SUVmax values of the malignant and benign groups were 4.4±2.3 and 4.0±1.0 respectively, and the difference was not significantly between the two groups. In 6 patients with prostate cancer, FDG uptake was observed focally in the peripheral zone of the prostate glands. There was no significant correlation between the SUVmax and the PSA levels in all patients. Conclusions Incidental FDG uptake in the prostate gland is a rare condition, but a substantial portion of which is associated with the cancer. Benign and malignant lesions of the prostate gland in FDG PET/CT imaging could not be reliably distinguished. On the other hand, the peripheral focally FDG uptake of prostate glands should be further examined with other clinical and labaratory evaluations.