PD26-03: Sequential Intravesical Gemcitabine and Docetaxel for BCG-Naïve High-Risk Non-Muscle Invasive Bladder Cancer

Ian M. McElree*, Ryan L. Steinberg, Alexander C. Martin, Jordan Richards, Sarah L. Mott, Paul T. Gellhaus, Kenneth G. Nepple, Michael A. O'Donnell, Vignesh T. Packiam, Iowa City, IA

Introduction: Bacillus Calmette-Guerin (BCG) is currently recommended as adjuvant therapy following complete transurethral resection of bladder tumor (TURBT) for high-risk non-muscle invasive bladder cancer (NMIBC). However, production shortages have precluded BCG in many urologic practices. In response to the BCG shortage, Gem/Doce has been utilized at our institution in the BCG-naïve setting. We report the outcomes of patients with high-risk BCG-naïve NMIBC treated with Gem/Doce.

Methods: We retrospectively reviewed all patients with BCG-naïve high-risk NMIBC treated with Gem/Doce from May 2013 through April 2021. Patients received 6 weekly intravesical instillations of sequential 1 gram gemcitabine and 37.5 mg docetaxel after complete TURBT. Monthly maintenance of 2 years was initiated if disease free at first follow-up. The primary outcome was recurrence-free survival (RFS). Recurrence was defined as tumor relapse in the bladder or prostatic urethra. Progression was defined as T-stage increase or development of muscle invasive or metastatic disease. Survival was assessed with the Kaplan-Meier method, indexed from the first Gem/Doce instillation (p < 0.05).

Results: One hundred seven patients with median follow-up of 15 months (IQR 8-26 months) were included in the analysis. There were 47 with any CIS, 55 with T1 disease, and 7 with micropapillary variant histology. Four patients did not complete a full induction cycle due to hematuria (3) and severe frequency/nocturia (1). RFS was 89%, 85%, and 82% at 6, 12, and 24 months, respectively (Figure 1). No difference in RFS was seen in patients with or without CIS (p=0.42). No patients had disease progression. One patient underwent cystectomy due to end-stage lower urinary tract symptoms (final pathology pTisN0). No patients died of bladder cancer. Overall survival was 84% at 24 months. 46 patients reported any symptoms during treatment, commonly urinary frequency/urgency (36%), hematuria (11%), and dysuria (8%).

Conclusions: In a large cohort of high-risk, BCG-naïve NMIBC patients, Gem/Doce showed excellent efficacy and durability (82% 2-year RFS). Prospective comparative analysis of Gem/Doce in BCG-naïve populations is warranted.

Source of Funding: This work was supported by the John & Carol Walter Family Foundation and the Carver College of Medicine.