Thesis (Ph.D)-Cairo University,2022.

Bibliography: p. 206-233.

Our prospective study included 131 male patients who were referred to our center from March 2020 till March 2022 with proven biochemical recurrent prostatic adenocarcinoma. The patients’ data and images were analyzed for the rate of detection of recurrence based on PROMISE criteria. Also, correlation between serum PSA level and detection rate of PSMA PET/CT was analyzed. Moreover, the PSMA PET/CT was evaluated in relation to the Gleason score (ISUP groups) whenever available and to ADT within 6 months before the scan. Results: The overall detection rate was 102/131 patients (77.8 %). There was positive relation between serum PSA before the scan and the positivity of PSMA PET/CT. Patients were subdivided according to their serum PSA level before the scan in to 5 groups as: <0.2 ng/ml, 0.2-0.5 ng/ml, >0.5-3 ng/ml, >3- 10 ng/ml and >10 ng/ml where the detection rates were 53.3%, 64.3%, 80.4%, 91.3% and 94.7% respectively. The most common sites of recurrence were operative bed/ radiated prostate, pelvic lymph nodes, osseous deposits, retro-peritoneal lymph nodes and visceral deposits. The pathology reports/results were available in 62 patients and our study revealed no relation between positivity of PSMA PET/CT and ISUP pathological groups as well as ADT 6 months prior to the scan. We found that a cutoff value for serum PSA level to differentiate between positive PSMA PET/CT scan from a negative one to be >0.73 ng/ml.