Assessing oncological outcomes of bladder-sparing treatments in patients with BCG-unresponsive and BCG-exposed non-muscle-invasive bladder cancer.

BACKGROUND

A subset of non-muscle invasive bladder cancer (NMIBC) patients falls between BCG-naïve and BCG-unresponsive, leading to the introduction of the 'BCG-exposed' category. We assessed oncological outcomes in BCG-unresponsive and BCG-exposed patients undergoing bladder-sparing treatments (BST).

METHODS

This retrospective study included BCG-unresponsive and BCG-exposed patients who underwent BST with BCG or a shift to different intravesical chemotherapy. Patients undergoing early RC after BCG failure (N = 14) were excluded. Kaplan-Meier (KM) curves estimated HG recurrence-free survival (HG-RFS) and progression-free survival (PFS).

RESULTS

Among 541 patients treated with BCG from January 2005 to September 2022, 102 (19%) met inclusion criteria: 66 (65%) were classified as BCG-exposed according to IBCG criteria, 36 (35%) as BCG-unresponsive. Median follow-up from BCG-failure was 43 months (Interquartile range: 21-70). Forty-nine patients had a second HG-recurrence after BST. Of these, 8 patients progressed. No difference in KM curves was observed between the 2 groups for HG-RFS (P = 0.47) and PFS (P = 0.77). The 3-year HG-RFS after BCG treatment was 57% (95% CI: 43%-69%) for BCG-exposed and 39% (95% CI: 21%-57%) for BCG-unresponsive (HR: 1.24; 95% CI: 0.69-2.21, P = 0.47).

CONCLUSION

Our analysis revealed no significant differences in HG-recurrence or progression rates between BCG-exposed and BCG-unresponsive patients. Stage at the time of BCG failure recurrence, rather than the interval since the last BCG treatment, emerged as the primary factor in determining subsequent management strategies. Validation through larger-scale studies is warranted.