Risk of Becoming Lost to Follow-up During Active Surveillance for Prostate Cancer.

Active surveillance (AS) has emerged as the preferred management strategy for many men with prostate cancer (PC); however, insufficient longitudinal monitoring may increase the risk of poor outcomes. We sought to determine rates of patients becoming lost to follow-up (LTFU) and associated risk factors in a large AS cohort. The Michigan Urologic Surgery Improvement Collaborative (MUSIC) maintains a prospective registry of PC patients from 44 academic and community urology practices. Over a 6-yr period (2011-2017), we identified patients managed with AS. LTFU was defined as any 18-mo period where no pertinent surveillance testing was entered in the registry. With a median surveillance period of 32 mo, the estimated 2-yr LTFU-free probability calculated by Kaplan-Meier method was 90% (95% confidence interval [CI]=89-92%). Both African American race (hazard ratio [HR]: 2.77, 95% CI=1.81-4.24) and Charlson comorbidity index ≥1 (HR: 1.55, 95% CI=1.08-2.23) were independently associated with increased risk of LTFU. There was variability in rates of estimated 2-yr LTFU-free survival across MUSIC practices, ranging from 52% (95% CI=21-100%) to 99% (95% CI=97-100%), with a median of 96% (interquartile range: 94-98%), although this did not reach statistical significance (p=0.076). These data reveal opportunities for urology practices to identify systems to reduce rates of LTFU and improve the long-term safety of AS. PATIENT SUMMARY: With a median observation period of 32 mo, an estimated 10% of patients will be lost to follow-up at the 2 yr time point while on AS. African American men and generally unhealthy patients were at increased risk, and there was variability from one urology practice to another. There is ample opportunity to improve the quality of the performance of AS.