Association of magnitude of cancer of the prostate risk assessment score change following biopsy gleason upgrade during prostate cancer active surveillance with adverse pathology at prostatectomy.

Abstract

76 Background: The occurrence of pathologic upgrading in men with prostate cancer (PCa) managed with active surveillance (AS) is a cause for concern and may prompt treatment; however the degree to which upgrading impacts further risk status is unclear. We evaluated the association between the Cancer of the Prostate Risk Assessment (CAPRA) score and adverse pathological outcomes following biopsy Gleason upgrading in men with PCa on AS. Methods: We retrospectively evaluated men with low and intermediate risk PCa managed with AS at our institution between 1993 and 2013 who received a minimum of two biopsies. We assessed change in CAPRA score between initial diagnosis and Gleason upgrade at repeat biopsy. Among patients proceeding to radical prostatectomy, multivariate models incorporating CAPRA change and reclassified CAPRA score were constructed to evaluate factors associated with adverse pathology and time to treatment. Results: We identified 312 men with PCa on AS who experienced pathologic upgrade on surveillance biopsy at a median of 24 months (IQR 12-47) and at a median age of 65.7 years (IQR 61-71). The median CAPRA score at diagnosis was 1 (IQR 1-2), and median change at upgrade was +2 (IQR 1-3). 196 patients (63.0%) were reclassified to higher CAPRA scores at upgrade, while 108 (34.7%) had CAPRA classification that remained unchanged. Seven (2.3%) patients had a decrease in CAPRA risk category after biopsy upgrade. In a multivariate logistic regression model, reclassification to high CAPRA risk category at upgrade was significantly associated with adverse pathology at RP (OR=21.34, 95% CI 2.58-176.57, p=0.0097). Conclusions: Recalculated CAPRA score following biopsy Gleason upgrade during AS is a strongly associated with adverse surgical pathology among treated patients. This finding supports the role of refined risk reassessment in men with PCa on AS, particularly in those experiencing upgrading on subsequent biopsy.