(325) Treatment patterns and disease recurrence among patients with high-risk non–muscle-invasive bladder cancer with carcinoma in situ who are unresponsive to Bacillus Calmette-Guérin treatment: A real-world analysis using SEER-Medicare data

Background: : Bacillus Calmette-Guérin (BCG) has been the standard of care for high-risk non–muscle-invasive bladder cancer (HR-NMIBC) for nearly five decades; however, up to 50% of patients become unresponsive to BCG. Among patients who are BCG-unresponsive HR-NMIBC with carcinoma in situ (CIS), there is limited data on recurrence and next treatments received.

Objective: : To describe real-world treatment patterns and disease recurrence among patients with BCG-unresponsive HR-NMIBC with CIS receiving bladder-sparing treatment.

Methods: : This retrospective longitudinal cohort study used SEER-Medicare Data (01/01/2007–12/31/2020) to identify patients aged ≥65 years with BCG-unresponsive HR-NMIBC with CIS (± papillary disease). Patients were considered BCG-unresponsive if they received guideline-recommended treatment within 365 days of BCG discontinuation after adequate induction (≥5 installations in 70 days) and maintenance (≥2 installations within 180 days). Disease recurrence (i.e., claim for transurethral resection of bladder tumor, biopsy, intravesical or systemic chemotherapy, radiotherapy, radical cystectomy, pembrolizumab, progression to MIBC or metastatic cancer, or bladder cancer-related death) for patients initiating intravesical chemotherapy or pembrolizumab as next treatment was described using Kaplan–Meier (KM) analyses.

Results: : Among 1,700 patients with HR-NMIBC with CIS receiving adequate BCG induction and maintenance, 193 (11%) received another guideline-recommended treatment within 365 days after BCG discontinuation and were considered BCG-unresponsive (mean age 74 years, 81% male, 93% White race, mean Quan-CCI 1.4, 29% history of smoking). Most (64%) received another intravesical chemotherapy as their next treatment after BCG discontinuation (mitomycin [64%], valrubicin [15%], gemcitabine [12%]); 4% received pembrolizumab. Among patients initiating intravesical chemotherapy or pembrolizumab as next treatment, median time to recurrence was 3.4 months (95% confidence interval: 2.9, 4.6). KM rates of recurrence were 45% at 3 months, 65% at 6 months, 75% at 12 months, 83% at 24 months, and 90% at 36 months.

Conclusions: : Patients with HR-NMIBC with CIS have limited options following BCG unresponsiveness and among those who are BCG-unresponsive, most received bladder-sparing treatments (i.e., intravesical chemotherapy or pembrolizumab), with 75% experiencing disease recurrence within one year. These findings underscore a significant unmet need for more effective bladder-sparing treatments for patients who are BCG-unresponsive HR-NMIBC with CIS.

Sponsorship:: Johnson & Johnson