Estimating the risks and benefits of Active Surveillance protocols for Prostate Cancer: A microsimulation study

To estimate the increase in prostate cancer mortality (PCM) and the reduction in overtreatment resulting from different Active Surveillance (AS) protocols, compared to treating men immediately.

We use a microsimulation model (MISCAN-Prostate), with natural history based on ERSPC data. We estimate probabilities of referral to radical treatment while on AS, depending on disease stage, with data from John Hopkins AS cohort. We sample 10 million men representative of the US population and we project the effects of applying AS protocols differing by time between biopsies, compared to treating men immediately.

AS with yearly follow-up biopsies for low-risk patients (≤ T2a-stage and Gleason 6) increases the probability of PCM to 2.6% (1% increase) and reduces overtreatment from 2.5% to 2.1% (18.4% reduction). With biopsies every three years after the first year, PCM increases by 2.3% and overtreatment reduces from 2.5% to 1.9% (30.3% reduction). Including intermediate-risk men (> T2a-stage or Gleason 3+4) in AS increases PCM by 2.7% and reduces overtreatment from 2.5% to 2.0% (23.1% reduction). These results may not apply to African-American men.

Offering AS for low-risk patients is relatively safe. Increasing the biopsy interval from yearly to up to every 3 years after the first year, will significantly reduce overtreatment among low-risk men, with limited PCM risk. This article is protected by copyright. All rights reserved.

BJU international. 2016 May 25 [Epub ahead of print]

Tiago M de Carvalho, Eveline A M Heijnsdijk, Harry J de Koning

Department of Public Health, Erasmus Medical Center, Rotterdam, The Netherlands., Department of Public Health, Erasmus Medical Center, Rotterdam, The Netherlands., Department of Public Health, Erasmus Medical Center, Rotterdam, The Netherlands.