Comparison of biochemical recurrence-free survival after radical prostatectomy among men in active surveillance following grade reclassification and men newly diagnosed with similar grade disease.

Abstract

117 Background: Stakeholders in a Patient-Centered Outcomes Research grant questioned the clinical implications of biopsy grade reclassification (GR) while on active surveillance (AS). Methods: We conducted a retrospective analysis of men undergoing radical prostatectomy (RP) from 1995-2015 at Johns Hopkins and identified 4 groups; 76 men in AS underwent RP following GR from Gleason score (GS) 6 to GS 7(3+4) [grade group 2], 2947 men underwent immediate radical prostatectomy (IRP) following a diagnosis of grade group 2, 122 men in AS underwent RP following GR to GS ≥ 7(3+4) [grade groups ≥ 2], and 4433 men underwent IRP following a diagnosis of grade groups ≥ 2. Biochemical recurrence free survival (bRFS) was the outcome of interest that was assessed using Kaplan Meir curves and a multivariate Cox regression model. Results: Men on AS had a higher proportion of low volume cancer (p <0.001; p <0.001) as compared to the IRP groups for both biopsy grade group 2 and biopsy grade groups ≥ 2, respectively. On the Kaplan Meier curve, bRFS was higher for men in the AS cohort compared to IRP group for both biopsy grade group 2 (p = 0.071) and for biopsy grade groups ≥ 2 (p = 0.046). However, on the multivariate Cox model adjusting for age at treatment, cancer volume, and PSAD, the difference in bRFS between the AS and IRP group was no longer significant; HR = 0.61 (95% CI, 0.23 to 1.67) for biopsy grade 2, HR = 0.77 (95% CI, 0.41 to 1.46) for biopsy grades ≥ 2. Conclusions: AS patients that are reclassified to grade group 2 and those reclassified to grade group 2 or above have a higher chance of bRFS after treatment as compared to those undergoing IRP with similar grades. This could help inform decisions regarding the risk of entering an AS program. [Table: see text]