Extraprostatic extension (EPE) of prostatic carcinoma: is its proximity to the surgical margin or Gleason score important?

Abstract

To examine the association between histopathological factors of extraprostatic prostate cancer and outcome. Patients with extraprostatic extension (EPE) without positive margins, seminal vesicle or lymph node involvement were analysed from a consecutive radical prostatectomy cohort of 1136 (2002-2006) for: (i) distance of EPE from the margin; (ii) Gleason score of the EPE; and (iii) extent of EPE. Log-rank, Kaplan-Meier, and Cox regression analyses were performed. The study included 194 pT3a, pN0, R0 patients with a median follow-up of 5.4 years, with 37 (19%) patients experiencing biochemical relapse (BCR). On univariable analysis, patients with a Gleason score of ≥8 in the extraprostatic portion showed increased incidence of BCR compared with those with Gleason scores of ≤7 (P = 0.03). The proximity of the EPE to the margin (0.01-7.5 mm) did not correlate with BCR. On multivariable analysis, the extent of EPE, the Gleason score of the dominant nodule or of the EPE portion did not correlate with BCR. Data from this study using current International Society of Urological Pathology Gleason scoring and EPE criteria indicate that close proximity of EPE to the margin is not associated with recurrence. Gleason score ≥8 within EPE is associated with an increased BCR risk on univariable analysis, but larger studies are required to confirm whether extensive Gleason pattern 4 in an EPE indicates increased risk in an otherwise overall Gleason score 7 cancer.