Assessing risk stratification in Bacillus Calmette-Guérin-treated high-grade Ta nonmuscle-invasive bladder cancer patients.

PURPOSE: According to European Association of Urology (EAU) guidelines, nonmuscle-invasive bladder cancer (NMIBC) is stratified by pathological stage and three clinical risk factors (age >70, size >3 cm, multiple lesions). High-grade (HG) Ta can be categorized as intermediate-risk (IR) or high-risk (HR). However, the 2021 EAU stratification is based on non-BCG-treated patients. This study investigated the predictive value of EAU risk groups and factors in TaHG treated with BCG.

METHODS

We retrospectively reviewed NMIBC patients treated with BCG from 2005 to 2022. Patients were stratified by EAU 2021 risk groups. The primary endpoint was HG recurrence-free survival (RFS).

RESULTS

Among 163 TaHG patients, 84 (54%) had one risk factor, 40 (23%) two, and 8 (4%) three. According to EAU 2021, 71% (115) were IR and 29% (48) HR. Median follow-up was 37 months (IQR 19-64). Three patients progressed to MIBC or M+. Three-year HG RFS was 84% (95% CI: 69-96), 80% (95% CI: 68-87), 83% (95% CI: 66-92), and 87% (95% CI: 38-98) for patients with 0, 1, 2, and 3 risk factors, respectively (P = 0.85). For IR and HR groups, 3-year HG RFS was 81% (95% CI: 76-90) and 84% (95% CI: 68-92) (P = 0.97). At Cox regression analysis, neither the number of risk factors nor HR classification was a predictor of HG recurrence (P = 0.9).

CONCLUSIONS

Progression to MIBC was rare in our real-world cohort of BCG-treated TaHG NMIBC, while HG recurrence rates mirrored those of T1HG cases. Neither the EAU 2021 risk groups nor individual clinical RFs predicted HG recurrence effectively. Development of recurrence-based risk models for TaHG NMIBC is therefore warranted.