Real-world treatment practices in patients with muscle invasive bladder cancer (MIBC) treated in Alberta, Canada.

e16596 Background: Contemporary real-world data on treatment practices for patients with localized bladder cancer is limited. In this study we examined treatment patterns for patients diagnosed with de novo MIBC in Alberta. In addition, we evaluated the impact of patient demographics on treatment selection. Methods: We conducted a retrospective, observational cohort study of patients diagnosed with de novo MIBC between 2010-2022 using population-level administrative databases. Data sources included Alberta Cancer Registry, Vital Statistics, Pharmaceutical Information Network, Health Practitioner Claims, Discharge Abstract Database and National Ambulatory Care Report System databases. De novo MIBC was defined as initial presentation of UC with stage T2-T4, N0-N3, and M0 urothelial bladder cancer. Patients were followed from diagnosis to last known contact with the healthcare system, end of 2021, or death. Treatment patterns were descriptively summarized with stratified analyses performed according to treatment. Kaplan-Meier technique was used to estimate median overall survival (OS). Results: Overall, 1,292 de novo MIBC patients were identified: 76% male, mean age of 73 years. Overall, 50.3% of underwent a radical cystectomy (RC), 9% received chemoradiotherapy, 3.6% chemotherapy only, 12% radiation only, and 25% did not receive active treatment. Of those receiving RC (n=651), 51% received perioperative chemotherapy. Overall, 43.5% of the cohort received neoadjuvant systemic therapy with 12.6% receiving adjuvant systemic therapy. Stratification by treatment revealed most patients receiving radiation or no treatment were >75 years (86% and 73%, respectively) with a Charlson comorbidity index (CCI) ≥1 (64% and 67% respectively). The majority of patients receiving RC or chemoradiotherapy were ≤75 year (77% and 63%) with a CCI=0 (61% and 53%).Median OS was 26 months from MIBC diagnosis and differed by treatment group: 83.3 months for RC with perioperative chemo, 42.4 months for RC w/o chemotherapy, 24.8 months for chemotherapy + radiation, 16.2 months for chemotherapy alone, 8.6 months for no therapy and 7 months for radiation alone. Conclusions: This real-world cohort of de novo MIBC demonstrates a significant use of definitive surgical care (50%) compared to chemoradiotherapy (9%) with over one third of patients not receiving curative intent treatment. Notably, 40% of patients received neoadjuvant systemic therapy, aligning to current guideline recommended treatment strategies. Variations in care were found as treatment modalities differed considerably based on patient characteristics. While this likely reflects appropriate clinical care, selection biases limit accurate conclusions regarding efficacy. These data highlight the need to better understand drivers for treatment selection in MIBC given potential influence on outcomes.