Does protocol heterogeneity in active surveillance influence clinical outcomes? Insights from a multicenter prostate cancer cohort.

Abstract

Purpose: Active surveillance (AS) is recommended for men with low-risk prostate cancer, but institutional variability exists in eligibility criteria, confirmatory biopsy policies, and monitoring schedules. This study assessed whether protocol heterogeneity influences surveillance duration, treatment transition, and surgical pathology outcomes.

Materials and methods: We retrospectively reviewed 232 men who initiated AS between 2014 and 2016 at three institutions with distinct protocols: Hospital A (Gleason Grade Group [GGG] 1-2, prostate-specific antigen [PSA] <15 ng/mL, confirmatory biopsy only if clinically indicated), Hospital B (GGG 1-2 within core limits, PSA <20 ng/mL, biennial biopsy), and Hospital C (GGG 1 within core limits, one confirmatory biopsy within 1-2 years, then biopsy if clinically indicated). Kaplan-Meier and Cox regression assessed AS continuation and treatment transition, while final GGG and pathologic stage were compared among men undergoing radical prostatectomy (RP).

Results: Median AS duration was 38.5 months. Five-year AS retention differed significantly: 53.2% (Hospital A), 79.8% (Hospital B), and 59.1% (Hospital C). Treatment transition occurred in 23.2%, 18.1%, and 44.0% of patients, respectively (p=0.003). Hospital B showed the lowest hazard of transition (hazard ratio [HR] 0.49 vs. Hospital A), whereas Hospital C had a higher hazard for RP (HR 1.87 vs. Hospital A). Final GGG and stage did not differ among RP specimens.

Conclusions: Institutional heterogeneity in AS protocols significantly influenced surveillance duration and treatment timing but not adverse pathology. Flexibility in protocol design may be acceptable if supported by confirmatory biopsy and risk-adapted monitoring, underscoring the need for evidence-based standardization.