Active Surveillance for Localized Prostate Cancer: Nationwide Observational Study.

The objective of this study was to investigate nationwide survival outcomes in men with localized prostate cancer managed on active surveillance. A total of 936 men with localized prostate cancer were initiated on active surveillance in Denmark in 2002 to 2012. Kaplan-Meier estimated curative treatment-free, hormonal therapy-free, castration resistant prostate cancer-free and cause specific survival was calculated. Prostate cancer was classified as very low risk in 223 men, low risk in 436, intermediate risk in 259 (87% were at favorable intermediate risk) and high risk in 18. Median followup was 7.5 years (IQR 6.1-9.1). Kaplan-Meier estimated 10-year curative treatment-free survival was 62.8% (95% CI 59.1-66.3), 10-year hormonal therapy-free survival was 92.2% (95% CI 89.2-94.4), 10-year castration resistant prostate cancer-free survival was 97.2% (95% CI 95.3-98.4) and 10-year cause specific survival was 99.6% (95% CI 98.6-99.9). Compared to men with low risk prostate cancer, those with intermediate risk prostate cancer had higher curative treatment-free survival (69% vs 56%, p = 0.008), lower hormonal therapy-free survival (88% vs 95%, p = 0.005) and similar castration resistant prostate cancer-free survival (95% vs 99%, p = 0.17). In this nationwide cohort 10-year cause specific survival was similar to that in prospective active surveillance cohorts. Our study supports the use of active surveillance in men with localized prostate cancer, including men with favorable intermediate risk characteristics.