BCG-refractory vs. BCG-relapsing non-muscle-invasive bladder cancer: a prospective cohort outcomes study

Patients with recurrent or persistent high-grade non-muscle-invasive bladder cancer after bacille Calmette-Guérin (BCG) therapy are termed "BCG failures." We hypothesize that BCG-refractory patients who fail to respond to BCG have worse outcomes after bladder-sparing treatments compared with BCG-relapsing patients whose tumors recur after at least a 6-month disease-free interval.

We screened 32 patients who had failed BCG therapy for eligibility in a multicenter investigational trial. BCG-refractory patients received instillations of a mycobacterial cell wall-DNA complex extract. BCG-relapsing patients were treated with additional BCG or other intravesical agents. Both groups of patients were followed prospectively with transurethral biopsy after 6 months, and cystoscopy every 3 to 6 months for more than 2 years. Median follow-up time for all patients was 53 months (range: 24-72 mo).

Seventeen patients were classified as BCG refractory and 15 patients defined BCG relapsing. Recurrence-free median survival time was 10 months for BCG-refractory patients receiving mycobacterial cell wall-DNA complex vs. 23 months for BCG-relapsing patients who received another induction course of BCG therapy (P = 0.002). Progression-free survival time was 18 months for BCG-refractory vs. 52 months for BCG-relapsing patients (P = 0.001). Of the 17 BCG-refractory patients, 8 (47%) have died vs. 3 (20%) of the 15 BCG-relapsing patients.

BCG-refractory and BCG-relapsing categories differentiate BCG-failed patients into high-and lower-risk prognostic groups that may be useful in guiding treatment strategies.