MP36-20 POTENTIALS OF 68GA-PROSTATE SPECIFIC MEMBRANE ANTIGEN PET/CT FOR PRIMARY DIAGNOSIS OF PROSTATE CANCER

Abstract

Introduction & Objectives: The current study is designed to test the hypothesis that prostate biopsy using 68Ga-PSMA PET/Trans Rectal Ultrasound (TRUS)fusion images may have a clinical impact in the subset of patients with a high suspicion of prostate cancer (PCa), a previously negative biopsy and contraindications to or negative multiparametric MRI (mpMRI). Material(s) and Method(s): This prospective study was performed at a tertiary high volume Hospital in order to use 68Ga-PSMA PET/CT in a selected subgroup of patients for diagnosis of primary PCa: Men with persistently elevated PSA and/or PHI (prostate health index)suspicious for PCa, negative digital rectal examination, and at least one negative biopsy (Protocol ICH: MpMRI new-1_2018_emended). The cohort comprised patients with either an equivocal mpMRI (PIRADS v2. <0,001). ROC analysis performed for optimal cut-off points demonstrated that a SUVmax >5.4 and a SUVratio >2.2 could identify clinically significant PCa (GS>=7)with an accuracy of 85.9% and 91.5%, respectively. In the subset of patients who had already performed mpMRI, we found instead no correlation between PIRADS and lesions GS, SUVmax or SUVratio-to-background. Conclusion(s): Our study confirms and expands previous preliminary findings. In patients with a high suspicion of cancer, despite previously negative biopsy and/or mpMRI, 68Ga-PSMA PET/CT is capable to detect malignant lesions and identify with a high sensitivity clinically relevant PCa.Copyright © 2019 European Association of Urology. Published by Elsevier B.V. All rights reserved.