Yang Li, Canhua Liang, Ziwei Feng, Shaohuan Lu, Guangzhao Wang, Guangyi Meng
Patients diagnosed during the immunotherapy era showed improved survival compared with those diagnosed during the pre-immunotherapy era. Socio-economic and geographical factors also play a critical role in prognosis, suggesting that personalized treatment strategies are essential for optimal patient outcomes.
BACKGROUND: Extensive-stage small cell lung cancer (ES-SCLC) is a highly aggressive malignancy with limited treatment options. Immune checkpoint inhibitors (ICIs) have marked the beginning of the immunotherapy era for SCLC. However, population-level survival trends following the introduction of immunotherapy remain unclear.
METHODS: We conducted a retrospective study using Surveillance, Epidemiology, and End Results (SEER) data from 2015 to 2021 to analyze survival outcomes in ES-SCLC patients before (2015-2017) and after (2019-2021) the introduction of ICIs. We employed propensity score matching (PSM) to adjust for confounding factors and used Cox regression models to identify prognostic factors. Kaplan-Meier analysis and log-rank tests were used to assess overall survival (OS) and cancer-specific survival (CSS).
RESULTS: A total of 7,214 patients were included. After PSM, patients diagnosed in the 2019-2021 cohort demonstrated significantly improved survival compared with those diagnosed in the 2015-2017 cohort. The median overall survival (mOS) improved from 4.0 months [95% confidence interval (CI): 4.0-4.0] in the pre-immunotherapy era to 5.0 months (95% CI: 4.0-5.0) in the post-immunotherapy era [hazard ratio (HR) =0.849, 95% CI: 0.800-0.902; P<0.001], indicating that patients diagnosed during the immunotherapy era experienced better survival than those diagnosed during the pre-immunotherapy era. Marital status, geographical area, and metastasis sites were identified as significant prognostic factors. Notably, brain metastasis did not significantly affect survival, likely due to advancements in treatment.
CONCLUSIONS: Patients diagnosed during the immunotherapy era showed improved survival compared with those diagnosed during the pre-immunotherapy era. Socio-economic and geographical factors also play a critical role in prognosis, suggesting that personalized treatment strategies are essential for optimal patient outcomes.