Objectives: Discordance between the Gleason score (GS) on needle biopsy (NB) and the GS of the radical prostatectomy (RP) specimen is a common finding. The objective of this study was to evaluate the prognostic significance of these discrepancies with respect to outcomes following RP.
Methods: In the study, 6625 men treated by RP were categorized as having NB=RP (68.8%), NB<RP (25.0%) or NB>RP (6.2%) GS, and stratified for analyses into RP GS groups. The Kaplan-Meier method was used to analyze differences in biochemical recurrence-free survival (BRFS), and multivariate Cox analyses were performed to estimate the independent relative risk of progression associated with GS discrepancies.
Results: Across multiple RP GS strata (3+4, 7, 8, 8-10), patients with a lower NB GS experienced significantly better BRFS than patients with equal NB and RP GS (all p<0.05). NB<RP GS was independently associated with better (pooled HR, 0.76, p=0.001) BRFS, within and across RP GS strata. Similarly, patients with NB>RP GS had poorer BRFS than patients with NB=RP GS across multiple RP GS strata (< or =3+3, 3+4, 7; all p<0.05). NB>RP GS was independently associated with worse (pooled HR, 1.91, p<0.001) BRFS probabilities, within and across RP GS strata.
Conclusions: Our data suggest that the GS of the NB adds additional prognostic value to the RP GS in a consistent manner that may be applicable to strategies of risk stratification and patient counseling after surgery.