Real-life nationwide characteristics and outcomes of small cell lung cancer over the last 20 years: Impact of immunotherapy on overall survival in a real-life setting

Abstract

Background: The KBP studies are real-life nationwide, prospective, multicenter cohort studies of patients diagnosed with primary lung cancer that have been conducted in French non-academic public hospitals each decade since 2000.

Methods: Patients were analyzed in three prospective cohorts using the same methodology. In this study, we describe and compare the characteristics and outcomes of patients with small cell lung cancer (SCLC), with a focus on treatments in the 2020 cohort.

Findings: 8999 patients with lung cancer were included in the 2020 cohort, of whom 1137 had SCLC. From 2000 to 2010 and 2020, the proportion of patients with SCLC decreased from 16.4 % to 13.5 % and 12.6 % respectively. Between 2000 and 2020, the proportion of women increased from 15.5 % to 35.7 %. 15.4 % of patients with SCLC had limited-stage (LS) disease and 84.6 % of patients had extensive-stage (ES) disease. The 1-year overall survival (OS) rate for all patients with SCLC increased from 34.4 % in 2000 to 38.4 % in 2020. For ES-SCLC, multivariate analysis weighted with "entropy balancing" by including age, sex, performance status, number of metastatic sites, and brain metastases indicated an improvement in median OS from 8.1 months in patients receiving chemotherapy only to 11.1 months in patients receiving chemotherapy plus immunotherapy (HR 0.62, p < 0.001).

Interpretation: The proportion with SCLC has decreased over time, but the proportion of women has increased. The 1-year OS rates have improved over 20 years. The KBP-2020 cohort suggests a benefit of immunotherapy on OS in patients with ES-SCLC in the real-life setting.

Keywords: Chemoradiotherapy; Chemotherapy; Immunotherapy; Non-academic public hospital; Radiotherapy; Real-world data; Small cell lung cancer.