Context: In 2005, the International Society of Urologic Pathology consensus conference recommended that men with biopsy Gleason score 3 + 4 or 4 + 3 prostate cancer and tertiary pattern 5 should have their cancer classified as Gleason score 8 or 9, respectively. Yet, the management of men with Gleason score 7 vs 8 or 9 prostate cancer differs.
Objective: To compare the prognostic significance of Gleason score 7 with tertiary grade 5 vs other Gleason scores with respect to time to prostate-specific antigen (PSA) failure in men with prostate cancer.
Design, setting, and patients: From 1989 to 2005, 2370 men with clinical tumor category 1c to 3b, node-negative, and nonmetastatic prostate cancer underwent definitive therapy with surgery or radiation therapy with or without hormonal therapy. A pathologist with expertise in genitourinary cancers assigned Gleason scores to the prostate needle biopsy specimens. Cox regression was used to assess whether a significant association existed between the presence of tertiary grade 5 in men with Gleason score 7 disease and time to recurrence compared with men with Gleason score 7 without tertiary grade 5, Gleason score 5 to 6, or 8 to 10 disease, adjusting for known prognostic factors and treatment.
Main outcome measure: Time to PSA failure.
Results: Men with Gleason score 7 and tertiary grade 5 disease had a significantly shorter time to PSA failure than men with 7 without tertiary grade 5 (median time, 5.0 vs 6.7 years, respectively; adjusted hazard ratio (HR), 0.56; 95% confidence interval [CI], 0.32-0.97; P = .04) or score of 6 or less (median time, 15.4 years; adjusted HR, 0.24; 95% CI, 0.13-0.43; P < .001). However, a significant difference was not observed when these men were compared with men with Gleason score 8 to 10 disease (median time, 5.1 years; adjusted HR, 0.96; 95% CI, 0.54-1.71; P = .90).
Conclusion: In this study population, men with prostate cancer having biopsy Gleason score 7 and tertiary grade 5 had a higher risk of PSA-failure when compared with men with Gleason score 7 without tertiary grade 5 and had a comparable risk with men with Gleason score 8 to 10.