Integrating tertiary Gleason pattern 5 into the ISUP grading system improves prediction of biochemical recurrence in radical prostatectomy patients

Although the presence of tertiary Gleason pattern 5 is reportedly related to unfavorable prostate cancer characteristics, few data are available regarding the effects of tertiary Gleason pattern 5 on the new ISUP (International Society of Urological Pathology) grading system in radical prostatectomy patients. In this study, we evaluated the effect of tertiary Gleason pattern 5 on biochemical recurrence following radical prostatectomy in patients with prostate cancer. We retrospectively evaluated 1000 patients with prostate cancer who underwent radical prostatectomy. The ISUP Grades were as follows: Grade 1, 16.3%; Grade 2, 48.1% (with tertiary Gleason pattern 5, 8.0% and without tertiary Gleason pattern 5, 40.1%); Grade 3, 21.9% (with tertiary Gleason pattern 5, 9.1% and without tertiary Gleason pattern 5, 12.8%); Grade 4, 3.9%; and Grade 5, 9.8%. Biochemical recurrence-free survival differed significantly among the five groups (Grade 1–5) (P