Outcomes of Active Surveillance after Initial Surveillance Prostate Biopsy

Purpose We analyzed the rates of disease reclassification at initial and subsequent surveillance prostate biopsy as well as the treatment outcomes of deferred therapy among men on active surveillance for prostate cancer. Materials and Methods From a prospective database we identified 300 men on active surveillance who had undergone initial surveillance prostate biopsy, with or without confirmatory biopsy, within 1 year of diagnosis. Of these men 261 (87%) were classified as having NCCN very low or low risk disease at diagnosis. Disease reclassification on active surveillance was defined as the presence of 50% or more positive cores and/or surveillance prostate biopsy Gleason score upgrading. Patients with type I disease reclassification included those with any surveillance prostate biopsy Gleason score upgrading, while patients with type II reclassification had to have primary Gleason pattern 4-5 disease on surveillance prostate biopsy. Outcomes after initial surveillance prostate biopsy were evaluated using actuarial analyses. Results At the time of initial surveillance prostate biopsy 49 (16%) and 19 (6%) patients had type I and type II disease reclassification, respectively. Those who underwent confirmatory biopsy had significantly reduced rates of type I (9% vs 23%, p=0.001) and type II (3% vs 9%, p=0.01) reclassification at initial surveillance prostate biopsy. For the 251 patients without disease reclassification at initial surveillance prostate biopsy the 2-year rates of subsequent type I and II reclassification were 17% (95% CI 0–24) and 3% (95% CI 0.1–7), respectively. For the 93 patients who received deferred therapy the 5-year biochemical progression-free probability was 89% (95% CI 79–98), including 95%, 82% and 70% among those without, and those with type I and type II disease reclassification, respectively. Conclusions Patients on active surveillance with stable disease at the time of initial surveillance prostate biopsy may be appropriate candidates for less intensive surveillance prostate biopsy schedules.