Objective: Assess the usefulness of ⁶⁸Ga-PSMA PET/CT in the evaluation of suspected cases of prostate carcinoma (PCa).

Method: Patients with suspected PCa based on elevated serum prostate specific antigen (PSA), suspicious findings on per rectal examination or ultrasound abdomen were referred for ⁶⁸Ga-PSMA PET/CT scan. Whole body PET (vertex to mid thigh) with non contrast CT was acquired 1 hour after injection of ⁶⁸Ga-PSMA HBED-CC. Focal abnormal increased or diffuse intense tracer uptake in the prostate was taken as scan positive for PCa. Absence of focal abnormal increased tracer uptake in the prostate gland was taken as scan negative for PCa.

Results: 103 consecutive patients (Range: 48-90 years, median age of 68 years) with suspected PCa were included in the study. Serum PSA value ranged from 1.0 to 4156ng/mL with a median of 11.34ng/mL.  45 (44%) patients were scan negative for PCa. Among these four patients underwent transrectal ultrasound (TRUS) guided prostate biopsy and were all negative for PCa. Rest of the 41 patients biopsy was avoided and are on follow up with serial PSA monitoring and clinical examination. 58 (56%) patients were scan positive for PCa. Among them 13 (22%) patients did not undergo biopsy for various reasons. In the rest 45 patients who underwent TRUS guided biopsy, 39 (87%) patients were positive for malignancy. 6 (13%) patients biopsy was negative for malignancy. 12 (27%) out of the 45 patients showed uptake outside the prostate gland suggestive of metastases which included 8 cases with bone metastases.

Conclusion: ⁶⁸Ga-PSMA PET/CT is an excellent non invasive imaging tool in the evaluation of suspected cases of PCa. In scan negative patients it helped in avoiding immediate biopsy. In scan positive patients, it helped in targeting the biopsy sites and also completed the staging (metastatic) workup.