Analysis of age influence on oncological results and toxicity of BCG immunotherapy in non-muscle invasive bladder cancer

Purpose The aim of this study was to analyse the influence of age on the treatment outcome and toxicity in patients with T1HG non-muscle invasive bladder cancers treated with BCG immunotherapy. Methods Data from 637 patients with primary T1HG bladder cancer who were treated between 1986 and 2016 in two academic centres were retrospectively reviewed. Median follow-up was 57 months. Patients were divided into two groups: younger (< 70 years old) and older (≥ 70 years old). Additional analyses in subgroups of older (> 75 and > 80) patients were performed. Log-rank test, Cox regression analysis, and propensity score matching were performed to compare the groups. Results There were 389 patients below and 248 patients above or equal 70 years old. Recurrence-free, progression-free, and cancer-specific survival rates did not differ significantly between younger and older patients. Recurrence-free survival for younger and older patients were 55.4% vs 52.9%, progression-free survival 75.9% vs 76.6%, and cancer-specific survival were 87.5% vs 89.9% (all p > 0.05). Differences in the oldest subgroups also did not reach statistical significance. In both regression analysis and propensity score matching, no statistically significant associations of age with any of analysed end-points were found. Finally, there were no statistically significant differences between younger and older group in terms of moderate and severe complications occurrence (47.6% vs. 44.5%; p > 0.05) Conclusions It was shown that increasing age was not associated with BCG immunotherapy oncological outcomes, or with BCG toxicity in T1HG non-muscle invasive bladder cancer.