Study on optimizing treatment decisions for patients with suspected prostate cancer using one-stop combined whole-body PSMA PET/CT and local PET/mpMRI imaging

Objective To evaluate the value of whole-body prostate specific membrane antigen (PSMA) PET/CT combined with local multi-parametric magnetic resonance imaging (mpMRI) (referred to as PSMA combined imaging) in optimizing therapeutic decision-making for patients with clinically suspected prostate cancer (PCa).

Methods The clinical, imaging, and histopathological examination data of 110 patients with suspected PCa who underwent PSMA combined imaging at the First Affiliated Hospital of Guangzhou Medical University from April to November 2024 were collected for a observational retrospective cohort study. The patients were aged (73.0±7.4) years. Patients with local PCa without distant metastasis who were excluded by PSMA combined imaging underwent radical prostatectomy (RP). The postoperative histopathological examination results of patients who underwent RP were used as the "gold standard" to compare the accuracy rates of PSMA combined imaging and mpMRI in the diagnosis of PCa T staging and N staging. All patients underwent collective film review and treatment decision-making by a multi-disciplinary PCa diagnosis and treatment team. The accuracy rates of PSMA combined imaging and mpMRI in diagnosing PCa staging were compared using the exact McNemar test.

Results Among the 110 suspected PCa patients, 4 patients (3.6%) were diagnosed as benign prostatic hyperplasia based on the results of PSMA combined imaging and preoperative puncture biopsy. The remaining 106 cases (96.4%) were clinically significant PCa (csPCa). Among the 106 csPCa patients, 40 patients (37.7%, 40/106) did not change their original treatment plans and underwent RP after PSMA combined imaging. The remaining 66 patients (62.3%, 66/106) adjusted their treatment plans. Among them, 41 patients (38.7%, 41/106) were transferred to systemic treatment due to the discovery of distant metastasis, while the remaining 25 patients (23.6%, 25/106) underwent neoadjuvant endocrine therapy before RP due to the elevation of tumor T and N staging. The accuracy rate of PSMA combined imaging for T staging in PCa patients (62.5% (25/40) vs. 45.0% (18/40), χ²=4.000, P=0.020) and the accuracy rate of N staging (80.0% (32/40) vs. 67.5% (27/40)) were higher than those of mpMRI (χ²=2.286, P=0.131).

Conclusions Compared to mpMRI, PSMA combined imaging has altered the clinical treatment decisions for 62.3% of PCa patients; PSMA combined imaging can significantly improve the accuracy rate of T and N staging in csPCa patients, providing a basis for individualized precision diagnosis and treatment.