4610 Background: Despite the increasing number of available treatment options, metastatic urothelial cancer (mUC) remains a challenging disease, characterized by high mortality and substantial rates of undertreatment worldwide. In this study, we aimed to describe treatment patterns and survival among patients with mUC in France. Methods: This retrospective study included adult patients with incident mUC between January 2017 and December 2023. The overall study cohort was divided into two subcohorts: treated, defined as initiating any systemic treatment within 120 days after index date and untreated (defined as not initiating any treatment within 120 days after index date). The index date was defined as diagnosis (first recorded ICD-10 code for metastasis) or start of systemic anticancer treatment. Overall survival (OS) was estimated using Kaplan-Meier method, calculated from the index date for the overall cohort and untreated subcohort, and from the initiation of first line (1L) treatment for the treated subcohort. Baseline characteristics including sex, age, and age-adjusted Charlson Comorbidity index (CCI) were compared between treated and untreated subcohorts using χ2 and Wilcoxon tests. Results: The study included 24,912 patients, male (77.8%), mean (SD) age was 75 (11) yrs, and median (IQR) age-adjusted CCI was 4 (2-5). Median (IQR) follow-up was 2.5 (1-10) months. Mortality was 90.8%, primarily due to malignant tumors (88.6%) among the recorded causes of death. Overall, 1L treatment was initiated in 10,562 pts (42.4%), with increasing annual rates from 2017 (38%) to 2023 (47%). Chemotherapy was the predominant 1L treatment (75.4%) followed by immune-oncology (IO) agents (24.5%). Of 7,960 pts receiving 1L chemotherapy, 4,193 (53%) did not receive any further treatment, and 2,184 (27%) patients received chemotherapy, 1,359 (17%) IO, and 224 (3%) antibody-drug conjugates in second line. Mean (SD) time from index date to 1L initiation was 18 (25) days and mean (SD) duration of 1L was 101 (155) days. Median OS was 2.5 (95% CI 2.4-2.6), 7.6 (7.4-7.8) and 1.1 (1.1-1.1) months for the overall cohort, treated and untreated subcohorts, respectively. It decreased with higher CCI scores: from 3.99 months for patients with CCI 0 to 1.54 months for those with CCI ≥5. Sex, age and CCI were significantly different between treated and untreated patients (p<0.0001). Conclusions: This nationwide population-based study showed that more than half of patients with mUC treated in real-world clinical practice in France did not receive 1L systemic treatment. Untreated individuals were mainly elderly, male, comorbid, and experienced poor survival. These findings underscore the importance of the early utilization and optimization of available therapies to improve outcomes, especially among untreated patients with mUC.
Barthelemy et al. (2026) studied this question.