Gleason Pattern 4 Tumor Volume Predicts Both Adverse Pathology, PSA Recurrence

Background: International Society of Urological Pathology (ISUP) Gleason Grade Groups 2 and 3 are determined by the relative proportions of patterns 3 and 4. Pattern 3 has been shown not to metastasize. However, a patient with a single 1 mm focus entirely pattern 4 is classified as GG4, while a patient with 4 mm of pattern 3 and 3 mm of pattern 4 is classified as GG2 in spite of having a greater amount of pattern 4 than the first patient. So the classification of patients into GG2 and GG3 and even GG4 (for select patients) may not be the best way of risk stratification for these patients with intermediate-risk prostate cancer. Objective: To determine if the volume of pattern 4 disease is more strongly associated with adverse pathology and recurrence than ISUP Grade Group classification. A second objective was to determine whether prostate-specific antigen (PSA) levels are determined by pattern 4 volume. Design: Retrospective analysis of a single Italian radical prostatectomy database more...