Association of age with response to preoperative chemotherapy in patients with muscle-invasive bladder cancer.

Purpose: To assess the association of patient age with response to preoperative chemotherapy in patients with muscle-invasive bladder cancer (MIBC).
Materials and Methods: We analyzed data from 1105 patients with MIBC. Patients age was evaluated as continuous variable and stratified in quartiles. Pathologic objective response (pOR; ypT0-Ta-Tis-T1N0) and pathologic complete response (pCR; ypT0N0), as well survival outcomes were assessed. We used data of 395 patients from The Cancer Genome Atlas (TCGA) to investigate the prevalence of TCGA molecular subtypes and DNA damage repair (DDR) gene alterations according to patient age.
Results: pOR was achieved in 40% of patients. There was no difference in distribution of pOR or pCR between age quartiles. On univariable logistic regression analysis, patient age was not associated with pOR or pCR when evaluated as continuous variables or stratified in quartiles (all p > 0.3). Median follow-up was 18 months (IQR 6-37). On Cox regression and competing risk regression analyses, age was not associated with survival outcomes (all p > 0.05). In the TCGA cohort, patient with age ≤ 60 years has 7% less DDR gene mutations (p = 0.59). We found higher age distribution in patients with luminal (p < 0.001) and luminal infiltrated (p = 0.002) compared to those with luminal papillary subtype.
Conclusions: While younger patients may have less mutational tumor burden, our analysis failed to show an association of age with response to preoperative chemotherapy or survival outcomes. Therefore, the use of preoperative chemotherapy should be considered regardless of patient age.
(© 2021. The Author(s).)