Predictors of Gleason score concordance after radical prostatectomy: A SEER analysis.

Abstract

e17146 Background: Discrepancies between clinical Gleason score (cGS) and pathological Gleason score (pGS) can alter prostate cancer prognosis and management. This study aims to quantify the concordance between cGS and pGS by identifying independent preoperative predictors of pathological upgrading and downgrading in a large population-based cohort. Methods: A retrospective cohort analysis was performed using the Surveillance, Epidemiology, and End Results (SEER) database on 59,567 men diagnosed with prostate adenocarcinoma between 2018-2022, who underwent radical prostatectomy with complete clinical and pathological data. The primary outcome was concordance between cGS and pGS. A multinomial logistic regression was performed to determine predictors of Gleason score upgrading and downgrading. Covariates included age, race/ethnicity, preoperative PSA, clinical T-stage, time to treatment, cGS, and the percent of positive biopsy cores. Results: Overall, 70.1% of patients had concordant GS, while 16.1% were upgraded and 13.8% were downgraded. Agreement between cGS and pGS was moderate (weighted kappa = 0.507). Among cGS 6 tumors, 67.0% were upgraded, while 57.5% of cGS 8 tumors were downgraded. In contrast, cGS 7 demonstrated the highest concordance rate of 90.5%. Upgrading was significantly associated with increasing preoperative PSA levels (OR 1.02 per ng/mL; p < 0.001) and prolonged interval from diagnosis to treatment (OR 1.03 per month; p < 0.001). Compared to Non-Hispanic White patients, Hispanic patients demonstrated a 12% increased odds of upgrading (OR 1.12; p = 0.011), while Non-Hispanic Black patients showed a 10% decreased likelihood (OR 0.90; p = 0.016). Downgrading was most strongly predicted by higher initial cGS (OR 5.23; p < 0.001) and lower clinical T-stage (T1-T3 versus T4; p < 0.001). Specifically, clinical T2 disease showed the highest likelihood of downgrading relative to T4 disease (OR 3.49; p < 0.001). Conclusions: Biopsy results often underestimate prostate cancer severity, with nearly one in six patients harboring more aggressive disease than initially detected, while high-risk clinical scores often overestimated pathological severity. These findings underscore the need for accurate risk stratification to avoid both undertreatment in high-risk groups and potential overtreatment in those with overestimated risk.