Refining Active Surveillance Eligibility in Intermediate-risk Non-muscle-invasive Bladder Cancer: The Impact of Time to First Recurrence

The International Bladder Cancer Group (IBCG) scoring system has been proposed for identifying patients suitable for active surveillance (AS) within the intermediate-risk (IR) non–muscle-invasive bladder cancer (NMIBC) population. Given that early recurrence has been associated with higher progression rates, we aimed to assess whether better integration of recurrence-free survival (RFS) into the IBCG risk stratification may further improve AS eligibility criteria. We retrospectively identified 241 recurrent IR-NMIBC patients (during the period 2013–2022) who were eligible for AS at the time of the first transurethral resection of a bladder tumor. Kaplan-Meier and multivariable Cox regression analyses evaluated the impact of IBCG risk factors and recurrence timing in predicting high-grade (HG) progression-free survival (PFS), while discrimination was assessed using Harrell's concordance index (C-index). Patients who recurred within 6 mo had significantly worse PFS than those with recurrence at >12 mo from diagnosis (3-yr PFS: 42% vs 74%, p = 0.007), while no difference in progression rates were observed for recurrence between 6 and 12 mo or at >12 mo. At a multivariable analysis, RFS was independently associated with HG progression and outperformed the IBCG risk group in predictive accuracy (C-index 0.78 vs 0.70). Integration of both factors in the model resulted in the highest performance (C-index 0.79). The time to first recurrence adds prognostic information beyond the IBCG criteria when selecting IR-NMIBC patients eligible for AS. Patients recurring within 6 mo should not be considered for surveillance, while those with later recurrences may remain eligible if no more than one IBCG risk factor is present. Prospective validation of the AS criteria in the IR cohort at each recurrence will further help refine patients’ selection and follow-up. Patient summary: In this study, we looked at patients with bladder cancer who might be monitored (active surveillance) without immediate treatment. We found that if the cancer comes back within 6 mo, there is a higher chance that it will become more aggressive.