MP13-17 THE EFFECT OF STAGING WITH 68GA-PSMA PET/CT IMAGING ON CLINICAL DECISION FOR TREATMENT PROTOCOL OF HIGH RISK PROSTATE CANCER PATIENTS

Abstract

INTRODUCTION AND OBJECTIVE: Staging in high risk prostate cancer patients (Gleason score >7, PSA >20 ng/mL, clinical stage T2c – 3a) with 68Ga-PSMA PET/CT is useful for detecting metastatic disease especially valuable for oligometastatic disease. It has shown to change the treatment protocol in patients with biochemical recurrence (BCR) however, there is still less data with the patients for recently diagnosed prostate cancer or staging. METHODS: Recently diagnosed prostate cancer patients suspected with metastatic disease, additionally patients with findings either Gleason score of higher than 7 or higher PSA values were included in our study. Fifty-seven patients with prostate cancer were scanned for staging. Between 3,6-5,5 mCi 68Ga-PSMA was injected. Patients were scanned 60 minutes after injection. Images were evaluated by two nuclear medicine specialists. Furthermore, two different urologists separately evaluated all patients for treatment protocol. First, the evaluation is done without PSMA PET/CT results and for second evaluation they have been given the results of the PSMA scans. RESULTS: Patient ages were between 36-86 years and mean PSA value was 152 (4,1-1957 ng/ml). All Gleason scores were higher than 7, except seven patients who had PSA values of >20ng/ml. 45% of the patients had positive findings for lymph node metastases; 28% of the patients had distant metastasis. Between 41% and 50% of changing rates were calculated for the treatment protocols after PSMA scan results. CONCLUSIONS: Several studies have already revealed the use of 68Ga-PSMA PET/CT in prostate cancer with the suspect of BCR. However, there is still debate about the use of PSMA imaging in staging prostate cancer patients. The patients in our series showed the contribution of PSMA imaging is not negligible with the change rates of 41-50% in treatment protocol. However further discussion with higher patient numbers is needed for the cost-effectiveness. Source of Funding: The authors declare no source of funding.