Comparison of the Efficacy of 68Ga-PSMA-11 PET/CT and 68Ga-PSMA-11 PET/MRI for Prostate Cancer Staging: Protocol of a Single-Center Prospective Study

Background: Prostate cancer is the most common malignancy in men; thus, its diagnosis is of utmost importance. With the advancement of imaging techniques, many diagnostic methods have become available, the most novel being prostate-specific membrane antigen (PSMA) positron emission tomography (PET). The specificity and sensitivity of PSMA PET/computed tomography (CT) for the diagnosis of prostate cancer have already been recognized. Current research focuses on the utility of PSMA PET/magnetic resonance imaging (MRI); however, almost all studies to date are retrospective. Therefore, we designed a prospective study to explore the diagnostic and staging efficacy of PSMA PET/MRI for prostate cancer by head-to-head comparison with PSMA PET/CT. Methods: : The study population will include patients with intermediate- or high-risk prostate cancer who will undergo both PSMA PET/CT and PSMA PET/MRI with a single contrast injection, followed by robot-assisted radical prostatectomy or systemic treatment. The imaging findings will be compared with the postoperative pathological findings to evaluate the diagnostic efficacy of PSMA PET/MRI for in situ tumors, extracapsular extension, and seminal vesicle invasion. Discussion: By head-to-head comparing the efficacy of PSMA PET/CT and PSMA PET/MRI with the use of pathological findings as control, we intend to support the use of PSMA PET/MRI in the diagnosis of PCa and determine the most suitable target population in clinical practice. Trial registration: This study has been registered at Chinese Clinical Trial Registry (ChiCTR2100042373)on January 21, 2021.