A Prospective Clinical Study Based on USTC Diagnostic Model and PSMA/PET-CT for Direct Radical Prostatectomy in Some Patients with First Negative Biopsy

Research design This is a prospective, single-center, single-arm, open-label clinical study conducted at the First Affiliated Hospital of the University of Science and Technology of China. Patients with no contraindications to surgery and who meet enrollment criteria will be included in the study. Subsequently, the investigators will recommend that these patients be treated again for PI-RADS≥4, first negative prostate puncture, high-risk group of USTC diagnostic model, and PSMA PET/CT positive patients. Laparoscopic radical prostatectomy (LRP) was directly performed. Transperineal targeted prostate biopsy was performed if intraoperative freeze pathology indicated prostate cancer, then LRP was performed; intraoperative freeze pathology indicated benign prostate biopsy, then transperineal prostate biopsy was performed.

The diagnostic efficacy of USTC diagnostic model combined with PSMA PET/CT was evaluated according to the pathological results of LRP postoperative specimens or prostate biopsy specimens, and whether such patients can directly undergo radical prostatectomy without repeated puncture was also discussed. Before surgery, patients and their families should be fully informed of the surgical risks, the necessity of pathologic confirmation of prostate biopsy, the possibility of benign prostate lesions, and other alternative treatments, including active monitoring, radiotherapy, and focal therapy.

Screening and registration This study consisted of a prostate cancer diagnostic model and a tandem examination of 18F-Prostate-specific membrane antigen 1007 positron emission tomography/computed tomography (18F-PSMA-1007 PET/CT).

For patients with PI-RADS≥4 and negative prostate puncture for the first time, the prostate magnetic resonance score was re-evaluated three months later. For patients with PI-RADS still ≥4, the serum prostate-specific antigen (PSA) test and multi-parameter magnetic resonance imaging (mpMRI) were completed. Prostate-specific antigen density (PSAD) and Prostate Imaging Reporting and Data System version 2.1 (PI-RADS v2.1) score information were obtained. Then through online diagnosis chart (website: https://ustcprostatecancerprediction.shinyapps.io/dynnomapp/) patients with clinically significant probability of the risk of prostate cancer (csPCa). When the csPCa prediction probability is equal to or greater than 0.60, 18F-PSMA-1007 PET/CT is used for further diagnosis. If a patient is still considered to have csPCa after an 18F-PSMA-1007 PET/CT examination, the investigators define this as a positive result. These patients met our study criteria. Notably, patients with a predicted probability of less than 0.60 will no longer receive 18F-PSMA-1007 PET/CT, and patients with a risk probability equal to or greater than 0.60 but negative 18F-PSMA-1007 PET/CT will not meet the inclusion criteria.