Perioperative chemotherapy use and related outcomes in muscle-invasive bladder cancer in Australia

Objectives

To explore Australian data on perioperative chemotherapy use and associated outcomes in muscle-invasive bladder cancer (MIBC).

Subjects and Methods

An observational study of patients with MIBC treated with neoadjuvant chemotherapy, adjuvant chemotherapy or surgery alone was conducted using data from BLADDA, a multicentre Australian urothelial cancer registry. Pathological response to neoadjuvant chemotherapy and its effect on event-free survival (EFS) and overall survival (OS) were determined. EFS and OS in patients who underwent neoadjuvant chemotherapy, adjuvant chemotherapy or surgery alone were compared using univariate and multivariable proportional hazards regression.

Results

From 2018 to 2024, 259 patients enrolled in the BLADDA registry met inclusion criteria, of which 45% received neoadjuvant chemotherapy, 23% received adjuvant chemotherapy, 1.2% received both neoadjuvant and adjuvant chemotherapy and 31% underwent surgery only. The proportion of patients treated with neoadjuvant chemotherapy increased over time. A total of 21 of 67 (31%) evaluable subjects achieved a pathological complete response, which was associated with improved EFS and OS. Excluding patients who received both neoadjuvant and adjuvant chemotherapy, the EFS hazard ratio (HR) was 0.43 (95% confidence interval [CI] 0.29–0.65, p < 0.001) for neoadjuvant chemotherapy and 0.59 (95% CI 0.38–0.94, p = 0.03) for adjuvant chemotherapy compared to surgery alone. Neoadjuvant chemotherapy was associated with prolonged OS in the univariate analysis (HR 0.43, 95% CI 0.26–0.73, p = 0.002) but not in the multivariable analysis (HR 0.59, 95% CI 0.32–1.08, p = 0.09). OS was not improved with adjuvant chemotherapy (unadjusted HR 0.76, 95% CI 0.44–1.31, p = 0.3; adjusted HR 0.86, 95% CI 0.46–1.60, p = 0.6).

Conclusion

Neoadjuvant chemotherapy use for MIBC in Australia has increased over the past decade, but it remains underutilised. This has important implications as perioperative chemo-immunotherapy emerges as a standard of care. Although a clear impact on survival in the overall population was not observed, this was potentially due to the limited sample size.