Purpose: Previously, Seoul National University (SNU) prostate cancer (PC) stage calculator was developed to predict the pathological stage of clinically localized PC after radical prostatectomy (RP) in Korean men. We evaluated its generalizability and compared their clinical values with 2013 Partin tables by Korean multicenter cohort.
Materials and Methods: Evaluated cohort consisted of 2,607 patients who had clinical stages T1c-T3a PC and were treated with RP at 14 institutions in Korea. After excluding 262 cases with prior hormone or radiation therapy and 604 cases with missing data, 1,741 cases were analyzed. Predictive accuracy was evaluated using the area under the receiver operating characteristic curve (AUC). The agreement between the predicted values with observed outcome was assessed with calibration plot. SNU PC stage calculator was compared with 2013 Partin tables applying to this cohort using DeLong method and decision curve analysis.
Results: The accuracies of SNU PC stage calculator was all higher than those of 2013 Partin tables to predict organ-confined disease (0.755 vs. 0.711, p<0.001), extraprostatic extension (0.743 vs. 0.665, p<0.001), seminal vesicle invasion (0.833 vs. 0.764, p<0.001), and lymph node metastasis (0.842 vs 0.760, p=0.019). The observed outcomes were well calibrated with their predicted values by the calculator. Decision curve analyses demonstrated higher net benefits of SNU PC stage calculator compared with 2013 Partin tables.
Conclusions: SNU PC stage calculator has been proved their generalizability among Korean population. Its clinical usefulness for Korean men was higher than 2013 Partin tables developed using Western cohort.