Adherence to active surveillance monitoring among Medicare beneficiaries with prostate cancer

Objectives To evaluate adherence to recommended active surveillance (AS) monitoring among Medicare beneficiaries with low-risk or favorable intermediate-risk prostate cancer and assess changes in adherence over time. Methods We conducted a population-based cohort study using Surveillance, Epidemiology, and End Results–Medicare data from 2012 through 2020. Men aged 65 years or older with low-risk or favorable intermediate-risk prostate cancer managed with AS were included. Adherence during the first 3 years after diagnosis was assessed using claims-based measures of prostate-specific antigen (PSA) testing and repeat biopsy among patients who remained under surveillance. Temporal trends were evaluated by year of diagnosis. Results The first-year analysis included 11,597 patients; 9,533 and 7,476 remained under surveillance at 2 and 3 years, respectively. Overall, 45.3% met the monitoring criteria in year 1, compared with 12.5% through year 2 and 10.7% through year 3. When the repeat-biopsy requirement was excluded, adherence was 31.7% through year 2 and 24.7% through year 3. Using a less stringent definition of at least 1 PSA test annually, adherence was 79.1% in year 1, 29.8% through year 2, and 30.8% through year 3. Adherence remained low across diagnosis years; no significant temporal trends were observed under the primary adherence definition. Conclusions Adherence to recommended AS monitoring among Medicare beneficiaries remained low, with no significant temporal improvement under the primary adherence definition despite increasing adoption of AS. Strategies are needed to improve longitudinal monitoring as becomes more widely used.