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

Abstract

5080 Background: Our initial phase I trial showed docetaxel to be a safe agent for intravesical therapy with no systemic absorption and minimal toxicity after 6 weekly instillations. In that trial, docetaxel appeared to show a 56% complete response (CR) but the durability was only 22% (no additional therapy) to 39% (CR with additional TURBT). Owing to this excellent initial response rate, a second group of patients were treated with a 6 week induction and then given monthly maintenance therapy with intravesical docetaxel for BCG refractory high-grade, non-muscle invasive bladder cancer (NMIBC). Methods: 13 patients with recurrent Ta (n=1), T1 (n=6), and Tis (n=6) TCC who failed at least one prior BCG treatment were treated. Induction therapy was administered to all 13 patients as 6 weekly instillations of 75mg intravesical docetaxel followed by single-dose monthly maintenance therapy for 9 additional instillations in 9 of the patients who experienced complete initial response. Initial response at 12 weeks from the start of induction therapy was evaluated by cystoscopy with biopsy and urine cytology. Follow-up consisted of quarterly cystoscopy with biopsy and cytology and periodic CT scans. Results: The median follow-up was 14.4 months for the entire cohort. Median duration of maintenance treatment was 9 months. 10/13 patients (77%) from the entire cohort had a complete initial response after induction, and 6/13 patients (46%) have remained disease-free in follow-up. Of those who failed, 6 patients underwent TURBT and one underwent cystectomy. 9/10 initial responders completed at least 3 doses of maintenance therapy to date, of whom 6/9 (67%) have remained recurrence-free. Conclusions: Monthly maintenance therapy with intravesical docetaxel appears to extend the durability of response to induction treatment for a select group of patients with BCG refractory high risk NMIBC and may decrease overall risk of recurrence in NMIBC. No significant financial relationships to disclose.