The long-term outcomes of Gleason grade groups 2 and 3 prostate cancer managed by active surveillance: Results from a large population-based cohort

Active surveillance (AS) is an accepted management strategy for low-risk prostate cancer (PCa), but its role in the management of favorable intermediate-risk PCa remains controversial. Most reports studying the role of AS for these men generally lack long-term followup and include small numbers of patients. Our objective was to report the outcomes of men diagnosed with Gleason grade groups (GGG) 2 and 3 PCa who were managed expectantly. Using administrative datasets and pathology reports, we identified all men who were diagnosed with GGG 2 and 3 PCa and managed expectantly between 2002 and 2011 in Ontario, Canada. Outcomes and associated factors were estimated using cumulative incidence function methods and multivariable Cox regression models, respectively. We identified 926 men who were managed expectantly (AS [n=374] or watchful waiting [n=552]). The eight-year cancer-specific survival was 94% and 89% for the AS and watchful waiting cohorts, respectively. Among AS men, 266 (71%) received treatment after a followup of approximately eight years. Cumulative AS discontinuation rates at one and five years were 30.5% and 65.1%, respectively. Expectant management of GGG 2 and 3 PCa may be an option for certain men. Notably for AS patients, the cancer-specific mortality at eight years was 6%, and over 65% of men underwent treatment within five years. Further studies are required to evaluate which patients, based on disease-specific features and competing health risks, would benefit the most from a conservative strategy.