Chemoradiotherapy improves disease control in muscle-invasive bladder cancer

Chemotherapy with 5-fluorouracil (5FU) and mitomycin C (MMC), when combined with radiotherapy, leads to better locoregional control over a 10-year window in patients with muscle-invasive bladder cancer (MIBC), a recent study has found.

Researchers conducted a long-term follow-up of BC2001, the largest randomized trial of bladder-sparing treatment for MIBC, which enrolled 360 patients who received either radiotherapy alone (n=178) or chemoradiotherapy (n=182). The primary study outcome was locoregional control; secondary ones included toxicity, salvage cystectomy, and disease-free survival, among others.

Cox regression analysis revealed that chemoradiotherapy was significantly better than radiotherapy alone, reducing the risk of locoregional recurrence by almost 40 percent (hazard ratio [HR], 0.61, 95 percent confidence interval [CI], 0.43–0.86; p=0.004). The same was true for invasive locoregional control (HR, 0.55, 95 percent CI, 0.36–0.84; p=0.006).

In turn, the relative benefit of chemoradiotherapy also led to better disease-related outcomes, such as a lower 5-year rate of cystectomy (HR, 0.54, 95 percent CI, 0.31–0.95; p=0.034).

Survival outcomes were also better with chemoradiotherapy, though not significantly so: disease-free (HR, 0.78, 95 percent CI, 0.60–1.02; p=0.069), metastasis-free (HR, 0.78, 95 percent CI, 0.58–1.05; p=0.089), bladder cancer-specific (HR, 0.79, 95 percent CI, 0.59–1.06; p=0.11), and overall (HR, 0.88, 95 percent CI, 0.69–1.13; p=0.3) survival.

“This updated report from a large randomized trial with 10-year follow-up provides strong evidence for concurrent chemoradiotherapy using MMC and 5FU as a standard of care for patients opting for organ-preservation therapy for MIBC,” the researchers said. “These results support organ preservation as a valid alternative to radical cystectomy for this patient group.”