Impact of Tumor Stage on Oncologic Outcomes of High-grade Bacillus Calmette-Guérin Unresponsive Non-muscle-invasive Bladder Cancer Undergoing Bladder-sparing Therapies.

Abstract

Background and objective: Current data on bacillus Calmette-Guérin (BCG)-unresponsive non-muscle-invasive bladder cancer (NMIBC) do not differentiate outcomes by clinical stage. The purpose of this study is to investigate the role of tumor stage in oncologic outcomes in BCG-unresponsive NMIBC undergoing bladder-sparing therapies.

Methods: Demographic and outcome data for patients with BCG-unresponsive NMIBC were reviewed at ten institutions. The Kaplan-Meier method was used to determine survival differences between the T1 ± carcinoma in situ (CIS), Ta alone, and CIS ± Ta groups. Exploratory analyses were conducted as follows: (1) T1 alone versus Ta alone versus CIS ± T1/Ta and (2) T1/Ta alone versus CIS ± T1/Ta.

Key findings and limitations: Among 401 patients, 137 (34%) were T1 ± CIS, 104 (26%) Ta alone, and 160 (40%) CIS ± Ta. Disease progression (p < 0.001), metastasis (p < 0.001), and bladder cancer mortality (p = 0.009) were increased in the T1 ± CIS group versus the Ta alone and CIS ± Ta groups. Cystectomy occurred most often in the CIS ± Ta and T1 groups (p = 0.002). Similar increases were noted in progression (p < 0.001), metastasis (p < 0.001), and bladder cancer mortality (p = 0.004) in T1 alone patients versus the Ta alone and CIS ± T1/Ta groups. There were no differences in outcomes between the T1 alone and T1 + CIS groups. No significant differences in metastasis, bladder cancer mortality, or all-cause mortality were noted when comparing papillary disease only with any CIS. The primary limitation of this study is likely a selection bias due to the retrospective nature of the cohort.

Conclusions and clinical implications: Presence of T1 disease is generally associated with worse oncologic outcomes compared with Ta or CIS. T1 and Ta should not be grouped together during comparison with CIS. Radical cystectomy appears largely driven by the presence of CIS.