Cruciferous vegetables help avert recurrence in NMIBC patients on BCG

Higher consumption of raw cruciferous vegetables appears to reduce the risk of recurrence in nonmuscle-invasive bladder cancer (NMIBC) patients treated with induction bacillus Calmette-Guérin (BCG), suggests a study.

Researchers obtained self-reported cruciferous vegetable intake, estimated isothiocyanate intake, and urinary isothiocyanate metabolites from 1,158 patients with incident NMIBC in the prospective Be-Well Study. They calculated hazard ratios (HRs) from Cox proportional hazards regression models for risk of first recurrences and random effects Cox shared frailty models for multiple recurrences.

Of the patients, 343 (30 percent) had a recurrence over a median follow-up of 23 months. Treatment with mitomycin C (MMC) and BCG resulted in reduced risks of first recurrence (MMC: HR, 0.58, 95 percent confidence interval [CI], 0.46‒0.73; BCG: HR, 0.66, 95 percent CI, 0.49‒0.88) and multiple recurrences (MMC: HR, 0.55, 95 percent CI, 0.44‒0.68; BCG: HR, 0.72, 95 percent CI, 0.55‒0.95).

Notably, patients on BCG and had high intake (>2.4 servings/month) of raw cruciferous vegetables had lower risks of recurrence (HR, 0.56, 95 percent CI, 0.36‒0.86; p=0.02 for interaction) and multiple recurrences (HR, 0.51, 95 percent CI, 0.34‒0.77; p<0.001 for interaction).

No change was noted in the inverse association between MMC therapy and recurrence risk.

“NMIBC has high recurrence rates and is often treated with MMC and BCG,” the researchers said. “Their efficacy relies on phase 2 enzyme metabolism and immune response activation, respectively.”