Prognostic G leason grade grouping: data based on the modified G leason scoring system

What's known on the subject? and What does the study add? The G leason scoring system is a well‐established predictor of pathological stage and oncological outcomes for men with prostate cancer. Modifications throughout the last few decades – most recently by the I nternational S ociety of U rological P athology ( ISUP ) in 2005 – have attempted to improve the correlation between biopsy and radical prostatectomy G leason sum and better stratify patients to predict clinical outcomes. Based on these clinical outcomes and the excellent prognosis for patients with low G leason scores, we recommend G leason grades incorporating a prognostic grade grouping which accurately reflect prognosis and are clearly understood by physicians and patients alike. Objective To investigate pathological and short‐term outcomes since the most recent G leason system modifications by the I nternational S ociety of U rological P athology ( ISUP ) in an attempt to divide the current G leason grading system into prognostically accurate G leason grade groups. Patients and Methods We queried the J ohns H opkins R adical P rostatectomy D atabase (1982–2011), approved by the institutional review board, for men undergoing radical prostatectomy ( RP ) without a tertiary pattern since 2004 and identified 7869 men. Multivariable models were created using preoperative and postoperative variables; prognostic grade group ( G leason grade ≤6; 3 + 4; 4 + 3; 8; 9–10) was among the strongest predictors of biochemical recurrence‐free ( BFS ) survival. Results Significant differences were noted among the G leason grade groups at biopsy; differences were noted in the race, PSA level, clinical stage, number of positive cores at biopsy and the maximum percentage of positive cores among the G leason grade groups at RP . With a median (range) follow‐up of 2 (1–7) years, 5‐year BFS rates for men with G leason grade ≤6, 3 + 4, 4 + 3, 8 and 9–10 tumours at biopsy were 94.6, 82.7, 65.1, 63.1 and 34.5%, respectively ( P < 0.001 for trend); and 96.6, 88.1, 69.7, 63.7 and 34.5%, respectively ( P < 0.001), based on RP pathology. Conclusions The 2005 ISUP modifications to the G leason grading system for prostate carcinoma accurately categorize patients by pathological findings and short‐term biochemical outcomes but, while retaining the essence of the G leason system, there is a need for a change in its reporting to more closely reflect tumour behaviour. We propose reporting G leason grades, including prognostic grade groups which accurately reflect prognosis as follows: Gleason score ≤6 (prognostic grade group I); Gleason score 3+4=7 (prognostic grade group II); Gleason score 4+3=7 (prognostic grade group III); Gleason score 4+4=8 (prognostic grade group (IV); and Gleason score 9–10 (prognostic grade group (V). </jats:list-i