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.