Prospective Evaluation of Selection Criteria for Active Surveillance in Japanese Patients with Stage T1cN0M0 Prostate Cancer

Objective: Selection criteria for active surveillance (AS) program of localized prostate cancer remain to be standardized. The purpose was to evaluate the validity of selection criteria and investigate the feasibility of this AS program. Methods: Patients meeting the criteria (i) stage T1cNOMO, (ii) age 50-80, (iii) serum prostate-specific antigen (PSA) 2y', which was defined as the proportion of patients who showed PSADT assessed at 6 months >2 years out of all the patients who chose AS. Point estimate of '%PSADT > 2y' was expected to be >80%. Results: One hundred and eighteen patients opted for AS and 16 chose immediate treatment at enrollment. PSADT for the initial 6 months based on four measurements could be assessed in 106 patients. Intent-to-treat analysis of'%PSADT > 2y' was 71.2% (84/118, 95% Cl: 62.1-79.2). Pathological progression rate at 1-year re-biopsy was 33%. Fifty-four (46%) patients remained on AS for maximal observation of 54 months. General health-related QOL in patients undergoing AS was not impaired. Conclusions: The primary endpoint, '%PSADT > 2y', did not meet the pre-specified decision criteria. Further prospective study with revised program and endpoint is needed.