The Role of Ga-68-PSMA PET/CT in the Initial Staging of Prostate Cancer – A Single Center 4 Year Experience

João P Lima,1 João Carvalho,1 Vasco Quaresma,1 Edgar Tavares-da-Silva,1 Rodolfo Silva,2 Paulo Azinhais,2 Gracinda Costa,2 Arnaldo Figueiredo1 1Urology and Renal Transplantation Department, Coimbra University Hospital Center, Coimbra, Portugal; 2Nuclear Medicine Department, Coimbra University Hospital Centre, Coimbra, PortugalCorrespondence: João P LimaUrology and Renal Transplantation Department, Coimbra University Hospital Center, Praceta R. Prof. Mota Pinto, Coimbra, 3004-561, PortugalEmail joaopedrosolima@gmail.comBackground: Recommended imaging modalities for prostate cancer staging have disappointing sensitivities, whereas [68Ga]-PSMA PET/CT (PET-PSMA) shows promising sensitivities and specificities in the initial management of prostate cancer. Recent studies have revealed that a significant change of management when PET-PSMA was used, with favorable negative predictive values.Methods: In this retrospective study, we analyzed every PET-PSMA performed in our center for initial staging of intermediate and high-risk prostate cancer. Patients were divided into two groups based on whether imaging modalities other than PET-PSMA were performed. In patients submitted to radical prostatectomy, PET-PSMA findings were compared to histological analysis of the specimen.Results: PET-PSMA results of 57 patients were gathered, with 77.2% (n=44) having performed CT scan or bone scan (BS) prior to PET-PSMA. Prostate cancer management strategy was changed in 61.4% (n=27), when PET-PSMA was performed following CT and BS. BS and CT results were consistent with PET-PSMA in 43.2% and 44.8%, respectively. In 30 cases, a curative strategy was used based on PET-PSMA findings. PET-PSMA revealed a negative predictive value of 95.2% in 23 patients submitted to radical prostatectomy with bilateral pelvic lymphadenectomy. Prostate SUV values on preoperative PET-PSMA correlated with initial PSA, ISUP grade, PC risk staging and presence of extraprostatic lesions.Conclusions: PET-PSMA is a key element for prostate cancer staging and management, with high diagnostic accuracy. More prospective studies need to be implemented to determine its role as a first-line staging tool.Keywords: PET-CT, prostate cancer, specificity and sensitivity, metastasis, lymphatic metastases, bone metastase