EORTC Risk Model to Predict Progression in Patients with Non-Muscle-Invasive Bladder Cancer: Is It Safe to Use in Clinical Practice?

Purpose To evaluate the validation of European Organization for Research and Treatment of Cancer (EORTC) risk tables to predict progression in Brazilian patients with non-muscle-invasive bladder cancer (NMIBC). Patients and Methods Two hundred five consecutively and prospectively selected patients with NMIBC who underwent transurethral resection were analyzed during 12 years. Six parameters were analyzed: tumor grade, size, and number, pT stage, previous recurrence rate, and carcinoma-in-situ. Time to progression, risk score, and progression probabilities were calculated and compared to probabilities obtained from the EORTC model. The C index was calculated, and accuracy was analyzed for external validation. Results A total of 152 patients had complete follow-up data, 36 died, and 17 were lost to follow-up. One hundred thirty-seven patients had primary tumors and 68 had recurrent tumors. Progression to muscle-invasive disease occurred in 42 patients (20.5%). Significant characteristics related to progression were male gender, pT1 stage, lesion size ≥ 3 cm, high grade of disease, and no combined intravesical therapy. Mean time to progression was 26.9 months; the 1-year progression rate was 3.4% and the 5-year rate was 19.1%. The C index was 0.86 at 1 year and 0.78 at 5 years. For calibration, 1- and 5-year progression rates were lower than the values predicted by EORTC risk tables, mainly in high-risk groups. Although the EORTC model overestimated the short- and long-term risk of progression, an overlapping of the confidence intervals between both populations was detected. Conclusion The EORTC model successfully stratified progression risks in a Brazilian cohort, although it overestimated progression rates. This scoring system is useful in predicting progression of NMIBC; however, updating new risk markers is essential to improve risk classification and prediction of progression.