Real-world survival outcomes with first-line chemoimmunotherapy and biomarker analysis in extensive-stage small-cell lung cancer.

[PURPOSE] The approval of programmed death-ligand 1 (PD-L1) inhibitors in the first line of treatment has transformed the therapeutic landscape of extensive-stage small cell lung cancer (ES-SCLC); real-world (rw) evidence of clinical benefit is currently limited. In this study, we investigated the rw efficacy of first-line chemoimmunotherapy and the role of potential biomarkers.

[METHODS/PATIENTS] We retrospectively assessed patients with SCLC receiving first-line chemoimmunotherapy at Sotiria Thoracic Diseases Hospital of Athens, Athens, Greece. Kaplan-Meier curves were used to calculate real-world progression-free survival (rwPFS) and real-world overall survival (rwOS). Cox proportional hazards regression analysis was utilized to identify associations between patient characteristics and outcomes.

[RESULTS] 188 patients were included. Median rwPFS was 6.5 months (95% CI 5.8-7.1 months) and median rwOS was 11.2 months (95% CI 9.1-12.0 months). rwOS was higher in the atezolizumab group compared with the durvalumab group (median, 12.0 vs 9.2 months; hazard ratio [HR], 1.51; 95% CI 1.06-2.15; p = 0.02), similar results were observed for rwPFS (median, 6.5 vs. 6.0 months, HR, 1.55; 95% CI 1.10-2.16; p = 0.01). In multivariate analysis, the difference between atezolizumab and durvalumab was not statistically significant, while lung, bone and liver metastases, ECOG PS, LDH and NLR were associated with an increased risk of death. Associations were utilized for the generation of a novel prognostic score with good discriminatory power (C-statistic: 0.73).

[CONCLUSIONS] Real-world efficacy of first-line chemoimmunotherapy in patients with ES-SCLC is comparable to randomized trials. The association between prognostic scores and survival outcomes in ES-SCLC should be explored in prospective studies.Query.