Evaluation of Triplet Therapy Combined with Robot-Assisted Cytoreductive Prostatectomy for High-Volume Metastatic Prostate Cancer: a Multicentre Randomised Controlled Trial Protocol.

BACKGROUND:Prostate cancer (PCa) is the second most common cancer in men. For patients with high-volume metastatic PCa (mPCa) who are fit for docetaxel, a triplet therapy regimen consisting of androgen deprivation therapy (ADT), chemotherapy, and an androgen receptor pathway inhibitor (ARPI) is recommended. Adding local radiotherapy to triplet therapy has been shown to alleviate symptoms and reduce disease progression. However, the benefit of combining triplet therapy with local surgery remains unclear and warrants further investigation in the present study. STUDY DESIGN:This is an open-label, prospective, two-arm, multicentre, randomised controlled trial. ENDPOINTS:Primary endpoints are progression-free survival (PFS) and the 1-year PFS rate. Disease progression is defined as prostate-specific antigen (PSA) progression, radiological progression, or unequivocal clinical progression. Secondary endpoints include overall survival (OS) and health-related quality of life (HRQoL). PATIENTS AND METHODS:Patients aged 18-75 years with high-volume mPCa will receive ADT (triptorelin 15 mg every 3 months), four-six cycles of chemotherapy (docetaxel 75 mg/m2 every 3 weeks), and an ARPI (rezvilutamide 240 mg once daily). Patients achieving a PSA level ≤0.2 ng/mL and deemed suitable candidates for surgery will be enrolled. A total of 88 eligible patients will be randomised in a 1:1 ratio. The control group will continue treatment with triptorelin and rezvilutamide, while the experimental group will receive robot-assisted cytoreductive prostatectomy in addition to triptorelin and rezvilutamide. Baseline PSA levels will be recorded and re-examined at each chemotherapy cycle and every 3 months thereafter. Radiological evaluations will be performed every 6 months. Clinical progression will be assessed based on pain severity, performance status, and the need to initiate new anticancer therapy. HRQoL will be evaluated every 3 months. PFS and OS will be estimated using Kaplan-Meier curves and compared with the log-rank test. TRIAL REGISTRATION:Chinese Clinical Trial Registry: ChiCTR2600121819.