OBJECTIVES: A better understanding of the clinical and economic burden of ES-SCLC across lines of treatment is required. We investigated baseline characteristics, treatment patterns, HCRU, real-world overall survival (rwOS), and time-to-next treatment or death (TTNT/D) of patients with ES-SCLC in Alberta, Canada.

METHODS: A retrospective, observational study leveraging administrative databases and a cancer registry was conducted. Eligible patients were aged 18 years+, had a diagnosis of SCLC between January 2012 and December 2021, and initiated first-line systemic anti-cancer therapy before 30 June 2022. TNM stage IV disease at diagnosis was considered a proxy for de novo ES-SCLC, limited stage disease at diagnosis was classified as recurrent ES-SCLC based on subsequent treatment >1 year after primary treatment.

RESULTS: 1,171 patients were included; 51.0% were male, mean age was 67.3 years. Mean time-to-treatment initiation from diagnosis was 25 days for 1^st line (1L), 301 days for 2^nd line (2L) and 548 days for 3^rd line (3L). Of 1,171 patients initiating 1L treatment, 312 (26.6%) and 71 (6.1%) received 2L and 3L treatment, respectively. In 1L, 83.7% of patients received platinum+etoposide (PE), the rest received etoposide or atezolizumab/durvalumab + PE. In 2L, 58.7% received PE, 14.1% received cyclophosphamide + doxorubicin + vincristine (CAV), the rest received etoposide, topotecan or irinotecan. In 3L, 29.6% received CAV, 23.9% received PE, and 19.7% received topotecan. During 1L treatment, patients spent 17.7 days hospitalized, had 10.1 cancer physician visits, 3.9 cycles of systemic therapy, and 10.7 days of radiation therapy, on average. Median rwOS was 7.8 months, 6.8 months, and 4.1 months in 1L, 2L, and 3L respectively. Median TTNT/D was 6.8 months, 5.5 months, and 3.9 months in 1L, 2L, and 3L respectively.

CONCLUSIONS: HCRU for ES-SCLC is high, and clinical outcomes worsen with each subsequent line of treatment; patients in later lines have the highest unmet need.