Does the extent of extraprostatic extension at radical prostatectomy predict outcome?—a systematic review and meta-analysis

Abstract

Extraprostatic extension (EPE) of prostate cancer is usually reported as either focal (F-EPE) or established (E-EPE), but data on the implication for outcomes of this subdivision are conflicting and no systematic review (SR) evaluating this exists. This SR aims to address this gap in the literature, focusing on the impact of F-EPE and E-EPE on outcome in radical prostatectomy (RP) patients. Searches on Embase, Medline(R), and Pubmed databases were conducted. Studies were included if they investigated the extent of EPE in RP patients and correlated this with defined outcomes (biochemical recurrence [BCR], death, metastasis). Quality was assessed using the Newcastle-Ottawa Scale. A random effects model was used for studies reporting hazard ratios (EPE extent and biochemical recurrence). 24 studies, including 49,187 men, were included. Six studies were of high quality. 20 studies reported how they measured EPE. 13 studies reported that the extent of EPE was associated significantly with BCR. Meta-analysis showed there was a significant correlation between BCR and both F-EPE and E-EPE when compared to organ-confined disease; no significant difference was found between F-EPE and E-EPE. This is the only SR to investigate the extent of EPE on outcomes after RP. EPE alone predicts outcome, but the value of subdivision by extent could not be demonstrated. Comparisons are limited due to variability in EPE assessment and in the methods used to report outcomes in the literature. Further work to standardize EPE reporting methods, in larger cohorts, may be helpful to resolve remaining questions.