DEPROMP Trial: The additive value of PSMA-PET/CT-guided biopsy for prostate cancer management in biopsy naïve men – study protocol for a randomized controlled trial

Abstract

Abstract Background: Primary objective: To determine the proportion of men with suspected prostate cancer (PCA) in whom the management plans are changed by additive Gallium-68 prostate-specific membrane antigen positron emission tomography/computed tomography (PSMA-PET/CT) guided prostate biopsy (PET-TB) in combination with standard of care (SOC) using systematic (SB) and multiparametric magnetic resonance imaging guided biopsy (MR-TB) compared with SOC alone. Major secondary objectives: To determine the additive value of the combined approach of SB + MR-TB + PET-TB (PET/MR-TB) for detecting clinically significant PCA (csPCA) compared to SOC; to determine sensitivity, specificity, positive and negative predictive value and diagnostic accuracy of imaging techniques, respective imaging classification systems and each biopsy method; to compare preoperatively defined tumor burden and biomarker expression and pathological tumor extent in prostate specimens. Methods: The DEPROMP study is a prospective, open-label, interventional investigator initiated trial. Risk stratification and management plans after PET/MR-TB are conducted randomized and blinded by different evaluation teams of experienced urologists based on histopathological analysis, imaging information: one including all results of the PET/MR-TB and one excluding the additional information gained by PSMA-PET/CT guided biopsy. The power calculation was centered on pilot data and we will recruit up to 230 biopsy-naïve men who will undergo PET/MR-TB for suspected PCA. Conduct and reporting of MRI and PSMA-PET/CT will be performed in a blinded fashion. Discussion: The DEPROMP trial will be the first to evaluate the clinically relevant effects of the use of PSMA-PET/CT in patients with suspected PCA compared to current SOC. The study will provide prospective data to determine the diagnostic yields of additional PET-TB in men with suspected PCA and the impact on treatment plans in terms of intra- and intermodal changes. The results will allow a comparative analysis of risk stratification by each biopsy method, including a performance analysis of the corresponding rating systems. This will reveal potential intermethod and pre- and postoperative discordances of tumor stage and grading, providing the opportunity to critically asses the need for multiple biopsies. Trail registration:The study was registered in the German Clinical Study Register (DRKS 00024134) on January 26, 2021. www.drks.de/drks_web/navigate.do?navigationId=trial.HTML&TRIAL_ID=DRKS00024134