Chemoradiation for muscle-invasive bladder cancer using 5-fluorouracil versus capecitabine: A nationwide cohort study

Oral capecitabine and intravenous 5-fluorouracil (5-FU) are both used as a radiosensitizer in chemoradiotherapy (CRT). A capecitabine-based regimen is more convenient for both patients and healthcare professionals. Since large comparative studies are lacking, we compared toxicity, overall survival (OS) and disease-free survival (DFS) between both CRT-regimens in patients with muscle-invasive bladder cancer (MIBC).

All patients diagnosed with non-metastatic MIBC between November 2017-November 2019 were consecutively included in the BlaZIB study. Data on patient, tumor, treatment characteristics and toxicity were prospectively collected from the medical files. From this cohort, all patients with cT2-4aN0-2/xM0/x, treated with capecitabine or 5-FU-based CRT were included in the current study. Toxicity in both groups was compared using Fisher-exact tests. Propensity score-based inverse probability treatment weighting (IPTW) was applied to correct for baseline differences between groups. IPTW-adjusted Kaplan-Meier OS and DFS curves were compared using log-rank tests.

Of the 222 included patients, 111 (50%) were treated with 5-FU and 111 (50%) with capecitabine. Curative CRT was completed according to treatment plan in 77% of patients in the capecitabine-based group and 62% of the 5-FU group (p = 0.06). Adverse events (14 vs 21%, p = 0.29), 2-year OS (73% vs 61%, p = 0.07) and 2-year DFS (56% vs 50%, p = 0.50) did not differ significantly between groups.

Chemoradiotherapy with capecitabine and MMC is associated with a similar toxicity profile compared to 5-FU plus MMC and no difference in survival was found. Capecitabine-based CRT, as a more patient-friendly schedule, may be considered as an alternative to a 5-FU-based regimen.