Comparison of clinical outcomes between upgraded pathologic Gleason score 3 + 4 and non-upgraded 3 + 4 prostate cancer among patients who are candidates for active surveillance.

PURPOSE

To clarify differences patients with pathological GS (pGS) 3 + 4 according to biopsy Gleason score (bGS) after radical prostatectomy (RP) among candidates for active surveillance.

METHODS

Between January 2006 and June 2014, 619 patients who met Royal Marsden criteria and had a pGS 3 + 4 after RP were identified. Patients were stratified into two groups according to bGS: Group A (n = 430) with bGS (3 + 3) and Group B (n = 189) with bGS 7 (3 + 4). Pathological outcomes were compared between the two groups, and the impact of bGS on adverse pathological outcomes was analyzed by logistic regression and biochemical recurrence (BCR)-free survival compared by log-rank test and the Cox proportional hazards model.

RESULTS

The patients in Group B had a higher rate of extracapsular extension (ECE), seminal vesicle invasion and positive surgical margins than those in Group A (p < 0.001, p = 0.005, p = 0.046, respectively). In univariate and multivariate, bGS was significantly associated with ECE [odds ratio (OR) 2.615, p < 0.001; OR 1.769, p < 0.001]. In Kaplan-Meier analysis, BCR-free survival rate was higher in Group A than in Group B (log rank, p = 0.037). In multivariable Cox regression, maximum percentage of core involvement were strongly associated with BCR [hazard ratio (HR) 1.773 (1.248-2.519), p = 0.001].

CONCLUSIONS

pGS 3 + 4 was associated with heterogeneous pathologic and biochemical outcomes according to bGS. Patients with pGS 3 + 4 upgraded from bGS 3 + 3 had more favorable pathological outcomes and biochemical survival outcomes than those with bGS 3 + 4.