Gleason Grading of Prostatic Carcinoma

Introduction

Dr. Donald F. Gleason, in collaboration with The Veterans Administration Cooperative Research Group, devised and, in 1966, first published the prostatic carcinoma grading system which bears his name.

The Gleason grading system gained increasing acceptance during the 1980's and, in 1993, it was recommended by a WHO Consensus Conference on prostatic carcinoma. Today, it is the most commonly used grading system for prostatic carcinoma worldwide. Multiple studies have confirmed that Gleason grade is a very powerful prognostic factor, both for the prediction of the natural history of prostatic carcinoma and for the assessment of the risk of recurrence after total prostatectomy or radiotherapy.

Few formal efforts have been made to teach the Gleason grading system, despite its wide-spread use. Further, with increasing experience over the years, some of the criteria for Gleason grading have evolved from those initially described. It is not surprising, therefore, that there are concerns about interobserver reproducibility of the system. It has been recently shown that interobserver reproducibility is strongly correlated with having learned Gleason grading at a meeting or a course and that it can be significantly improved by formal educational efforts.

The purpose of this website is to improve pathologists' knowledge of, and facility with, Gleason grading. In addition to presenting the classical Gleason patterns, it emphasizes problem areas including undergrading, cribriform and fused gland histology, histology "borderline" between Gleason grades, and grading prostatic carcinoma variants. treatment effects, prognostic significance, correlations between Gleason grade of core biopsies and subsequent prostatectomies, and studies of interobserver reproducibility are presented, as well as possible ways to report Gleason grades in sets of needle biopsies.