Objectives: Gleason score 7, in different proportions of grades 3 and 4, is the score most frequently assigned to prostate cancer in our radical prostatectomy specimens (RPSs). We correlated the major grade component of score 7 tumors with clinicopathologic parameters and disease-free survival.
Methods: All Gleason score 7 RPSs were classified as having a major grade of 3 or 4 carcinoma. The two groups were compared according to patient age, race, serum prostate-specific antigen (PSA) level, clinical and pathologic stage, tumor volume, and biochemical recurrence.
Results: Of the 534 patients analyzed, 356 and 178 had major grade 3 or 4 tumors, respectively. Compared with patients with 3+4 tumors, those with 4+3 had significantly more advanced clinical and pathologic stages, larger tumor volume, higher preoperative PSA levels, and older age and a higher proportion were African American (P <0.05 for all above parameters). With a mean follow-up of 34.6 months, patients with 3+4 tumors experienced lower rates of PSA recurrence than did those with 4+3 tumors (P = 0.0021). Furthermore, for the subset of patients with organ-confined disease, multivariable analysis that included race, age, clinical stage, preoperative PSA level, tumor volume, and major grade component found only the latter to be a significant predictor of recurrence, with patients who had major grade 4 component tumors experiencing a higher incidence of PSA recurrence than those with major grade 3 tumors (P = 0.012).
Conclusions: The major grade 4 component in Gleason score 7 carcinoma indicates a higher likelihood of biochemical recurrence, particularly for the increasing proportion of patients with organ-confined disease after radical prostatectomy.