Predictors of Pathologic Progression on Biopsy Among Men on Active Surveillance for Localized Prostate Cancer: The Value of the Pattern of Surveillance Biopsies

Abstract

BackgroundA better understanding of the independent predictors of disease progression for prostate cancer (PCa) patients is needed to improve the selection of ideal candidates for active surveillance (AS) and refine the surveillance regimen. ObjectiveTo examine the association of clinical and pathologic characteristics, as well as patterns of surveillance biopsy results, with the risk of progression in men on AS. Design, setting, and participantsThe retrospective study consisted of men with PCa who were on AS in the prospectively maintained University of California, San Francisco, institutional database from 1996 to 2011. Strict criteria for AS were prostate-specific antigen (PSA) ≤10 ng/ml, clinical stage T1 or T2, biopsy Gleason grade 6, <33% positive cores, and <50% tumor in any single core. Men were then categorized based on results of their confirmatory surveillance biopsy. Outcome measurements and statistical analysisDisease progression was defined as an increase in Gleason grade and/or biopsy volume beyond prespecified cut points. Serial biopsy patterns over the course of surveillance were stratified by confirmatory biopsy findings: negative, positive without progression, and positive with progression. Multivariable logistic regression models were used to evaluate predictors of progression during AS. Results and limitationsA total of 465 men met inclusion criteria (median follow-up: 51 mo). Of these men, 23% had negative confirmatory biopsies. Only 3% of the men (1 of 30) progressed by the fourth surveillance biopsy following a biopsy pattern of negative confirmatory and negative third biopsy findings. Negative confirmatory biopsy and lower PSA density (both p<0.01) were independently associated with decreased odds of biopsy progression at 3 yr. The main limitation of this study is its observational nature. ConclusionsThe patterns of surveillance biopsy results yield additional important information in AS. Negative confirmatory biopsy and PSA density are important independent predictors of progression on AS and may be used to better counsel men opting for AS.