A single-institution experience with induction and maintenance intravesical docetaxel in the management of non-muscle-invasive bladder cancer refractory to bacille Calmette-Guerin therapy

OBJECTIVE To analyse the durability of response for patients with non-muscle-invasive bladder cancer (NMIBC) refractory to bacille Calmette-Guerin (BCG) therapy and treated with intravesical docetaxel in a combined induction and maintenance regimen. PATIENTS AND METHODS A previous phase I trial showed docetaxel to be safe for intravesical therapy, with no systemic absorption and minimal toxicity after six weekly instillations for patients with BCG-refractory NMIBC. In that trial, docetaxel gave a 56% complete response (CR) rate at 12 weeks, but the durability was only 22%. Thus a second group of patients was treated with a 6-week induction and then given monthly maintenance therapy with intravesical docetaxel. Thirteen patients with BCG-refractory Ta, T1, or Tis transitional cell carcinoma were treated. Induction therapy was administered as six weekly intravesical instillations of 75 mg followed by single-dose monthly maintenance therapy for nine additional instillations in patients who had a CR. The initial response at 12 weeks from the start of induction therapy was evaluated by cystoscopy with biopsy, and urine cytology. The follow-up consisted of quarterly cystoscopy with biopsy and cytology, and periodic imaging. RESULTS The median follow-up was 13 months; 10 of 13 patients had a CR after induction, and six have remained disease-free during the follow-up. Of those in who the treatment failed, six had transurethral resection of the tumour and one a cystectomy. All 10 initial responders completed at least three instillations of maintenance therapy to date (median nine instillations), of whom six have remained recurrence-free. CONCLUSION Monthly maintenance therapy with intravesical docetaxel appears to extend the durability of response to induction treatment for a selected group of patients with BCG-refractory NMIBC, and might decrease the overall risk of recurrence in high-risk NMIBC.