Outcome Differences Between Subgroups of Favorable Intermediate Risk Prostate Cancer After Radical Prostatectomy

Area of Science:

• Urology
• Oncology
• Cancer Research

Background:

• Prostate cancer Grade Group 1 (GG1) is typically low-risk, but D'Amico criteria classify GG1 tumors with prostate-specific antigen (PSA) 10-20 ng/mL as intermediate risk (IR).
• This classification suggests potential heterogeneity within GG1 tumors regarding metastatic potential.

Purpose of the Study:

• To evaluate oncologic outcomes in patients with GG1 tumors exhibiting intermediate-risk features after prostatectomy.
• To investigate the heterogeneity of GG1 tumors within the intermediate-risk spectrum.

Main Methods:

• Retrospective analysis of 2703 patients undergoing robot-assisted radical prostatectomy (RARP) between July 2003 and June 2023.
• Patients were categorized into GG1-FIR (GG1 with PSA 10-20 ng/mL) and GG2-FIR (GG2 as the sole IR feature).
• Comparison of overall survival (OS), biochemical recurrence-free survival (BCRFS), time to radiotherapy, and pathological outcomes using Kaplan-Meier and Cox models.

Main Results:

• Of 553 patients meeting FIR criteria, 103 were GG1-FIR and 450 were GG2-FIR.
• No significant differences in long-term OS (15-year: 62.2% vs. 69.5%) or BCRFS (15-year: 84.2% vs. 81.2%) were observed between GG1-FIR and GG2-FIR groups.
• Pathological outcomes, including upstaging (24.3% vs. 30.4%) and nodal positivity (3.3% vs. 2.1%), were comparable.
• Sensitivity analysis showed GG1-FIR had similar OS but worse BCRFS compared to a low-risk cohort.

Conclusions:

• Patients with FIR prostate tumors demonstrate similar long-term oncologic outcomes following RARP.
• GG1 tumors exhibit varied behavior based on PSA levels; high PSA in GG1 tumors correlates with outcomes similar to clinically significant prostate cancer.