The Absolute Effect / Bladder Cancer / Medical
After induction BCG for high-risk NMIBC, does a low-frequency maintenance schedule of one BCG instillation every 3 months for 3 years reduce recurrence or progression compared with induction alone?
397 randomized patients with high-risk NMIBC: 195 to induction alone and 202 to induction plus maintenance. Induction was once weekly for 6 weeks.
At 5 years, relapse was 33.5% with induction alone versus 38.5% with maintenance: absolute difference +5.0 percentage points. HR for disease-free interval 0.83 (95% CI 0.61–1.13), p=0.20. Five-year progression was 16.0% versus 19.5%: +3.5 points; HR 0.79 (95% CI 0.50–1.26), p=0.30.
Because the randomized point estimates did not demonstrate benefit and the trial was not designed to establish superiority for a fixed-time absolute benefit, an NNT is not applicable.
Twenty patients stopped maintenance because of toxicity versus five in the induction-only group. Common local effects included frequency, dysuria and haematuria.
Three-monthly BCG maintenance for 3 years after induction did not reduce recurrence or progression in CUETO 98013. The result should not be generalized to other maintenance schedules such as the SWOG schedule.
CUETO 98013 informs the role of maintenance BCG after induction for high-risk non-muscle-invasive bladder cancer. Contemporary practice uses risk-adapted full-dose induction and maintenance where feasible, balancing recurrence/progression risk against toxicity, supply and patient tolerance; very-high-risk disease may warrant discussion of early cystectomy rather than repeatedly extending intravesical treatment.
CUETO 98013 primary/registry source ↗ · Current guideline guidance ↗