International multicentre study examining selection criteria for active surveillance in men undergoing radical prostatectomy

BACKGROUND: The controversies concerning possible overtreatment of prostate cancer, highlighted by debate over PSA screening, have highlighted active surveillance (AS) as an alternative management option for appropriate men. Regional differences in the underlying prevalence of PSA testing may alter the pre-test probability for high-risk disease, which can potentially interfere with the performance of selection criteria for AS. In a multicentre study from three different countries, we examine men who were initially suitable for AS according to the Toronto and Prostate Cancer Research International: Active Surveillance (PRIAS) criteria, that underwent radical prostatectomy (RP) in regards to: 1. the proportion of pathological reclassification(Gleason score >= 7, >= pT3 disease), 2. predictors of high-risk disease, 3. create a predictive model to assist with selection of men suitable for AS. METHODS: From three centres in the United Kingdom, Canada and Australia, data on men who underwent RP were retrospectively reviewed (n = 2329). Multivariable logistic regression was performed to identify predictors of high-risk disease. A nomogram was generated by logistic regression analysis, and performance characterised by receiver operating characteristic curves. RESULTS: For men suitable for AS according to the Toronto (n 800) and PRIAS (410) criteria, the rates for upgrading were 50.6, 42.7%, and upstaging 17.6, 12.4%, respectively. Significant predictors of high-risk disease were: Toronto criteria: increasing age, cT2 disease, centre of diagnosis and number of positive cores. PRIAS criteria: increasing PSA and cT2 disease. Cambridge had a high pT3a rate (26 vs 12%). To assist selection of men in the United Kingdom for AS, from the Cambridge data, we generated a nomogram predicting high-risk features in patients who meet the Toronto criteria (AUC of 0.72). CONCLUSION: The proportion of pathological reclassification in our cohort was higher than previously reported. Care must be used when applying the AS criteria generated from one population to another. With more stringent selection criteria, there is less reclassification but also fewer men who may benefit from AS. British Journal of Cancer (2012) 107, 1467-1473. doi:10.1038/bjc.2012.400 www.bjcancer.com Published online 4 October 2012 (C) 2012 Cancer Research UK