Aim: To develop a modified risk stratification scheme for localized prostate cancer incorporating percent of positive cores (PPC).
Methods: SEER database was accessed for eligible patients. Assessment of the prognostic value of PPC was conducted in a multivariate Cox regression model. A modified risk stratification scheme was proposed.
Results: In a multivariate model, higher PPC was associated with worse cancer-specific survival (p < 0.0001). A modified risk-stratification scheme was proposed incorporating PPC. Concordance index was evaluated and the results were: D'Amico model: 0.782 (SE: 0.014; 95% CI: 0.755-0.810); modified model: 0.809 (SE: <0.001; 95% CI: 0.781-0.837).
Conclusion: Integration of PPC into the risk stratification model for localized prostate cancer improves its performance.
Keywords: localized disease; positive cores; prognosis; prostate carcinoma.