Gleason 6 Prostate Cancer: Predictors of Upgrading in a High-Volume Turkish Tertiary Center

Gleason score 6 prostate cancer is generally considered a low-risk disease; however, pathological upgrading after radical prostatectomy remains frequent and clinically relevant. Reliable preoperative predictors are needed to improve risk stratification and treatment decision-making, particularly in populations with limited access to advanced imaging.

We retrospectively analyzed 338 patients with biopsy-confirmed Gleason score 6 prostate adenocarcinoma who underwent radical prostatectomy between 2013 and 2025 at a tertiary referral center in Turkey. Clinical, biopsy, and imaging variables were assessed. Independent predictors of upgrading were identified using multivariable logistic regression analysis, and model performance was evaluated using receiver operating characteristic (ROC) curve analysis.

Gleason score upgrading occurred in 193 patients (57.1%). Patients with upgrading had significantly higher PSA levels, higher PSA density values, and smaller prostate volumes (all p<0.05). Adverse pathological features, including extracapsular extension, seminal vesicle invasion, and positive surgical margins, were more frequent in the upgraded group (all p<0.01). PSA density (OR 40.07 per 1 unit increase, p=0.001) and age (OR 1.05 per 1 year increase, p=0.016) were identified as independent predictors of upgrading. A PSA density cut-off value of 0.125 yielded a sensitivity of 69.9% and a specificity of 48.3% (AUC=0.622).

Gleason score upgrading is common among patients with biopsy Gleason 6 prostate cancer. PSA density and age were independently associated with pathological upgrading, whereas traditional biopsy tumor burden parameters appeared to have limited predictive value. Although a PSA density threshold of 0.125 demonstrated only modest discriminative ability, PSA density may provide additional information as an adjunct to preoperative risk assessment among surgically treated patients.