Real-World Study Confirms Survival Benefit of First-Line Chemoimmunotherapy in Extensive-Stage Small Cell Lung Cancer

Clinical Summary:

• Design/Population: This retrospective real-world study compared first-line chemoimmunotherapy with platinum-based chemotherapy and non-platinum chemotherapy in patients with newly diagnosed extensive-stage small cell lung cancer (ES-SCLC).

• Key Outcomes: Chemoimmunotherapy significantly improved overall and progression-free survival compared with platinum-based chemotherapy. Thoracic and brain radiotherapy were independently associated with improved survival, and immune-related adverse events correlated with more favorable clinical outcomes.

• Clinical Relevance: These findings support first-line chemoimmunotherapy as the preferred treatment approach for ES-SCLC in routine clinical practice and suggest that consolidative radiotherapy may further improve outcomes.

Results from a real-world study demonstrated that first-line chemoimmunotherapy significantly improved overall survival (OS) and progression-free survival (PFS) compared with chemotherapy alone in patients with extensive-stage small cell lung cancer (ES-SCLC), supporting the role of multimodal treatment strategies in routine clinical practice.

“Phase 3 studies have shown significantly improved [OS] with the addition of PD-L1 inhibitors to platinum-based chemotherapy, establishing chemoimmunotherapy as the new first-line standard,” stated Kyriaki Dimitriou, MD, Heidelberg University Hospital, Heidelberg, Germany, and coauthors. “This study investigates the real-world efficacy of [chemoimmunotherapy] compared to alternative first-line regimens in patients with ES-SCLC.”

In this retrospective analysis, investigators evaluated 904 patients with newly diagnosed ES-SCLC treated between 2010 and 2022. Patients received first-line chemoimmunotherapy (n = 203), platinum-based chemotherapy (n = 530), or non-platinum chemotherapy (n = 171). The primary end points were OS and PFS. Secondary analyses evaluated the impact of thoracic radiotherapy, brain radiotherapy, and immune-related adverse events.

Median OS was 10.2 months with chemoimmunotherapy, 9.4 months with platinum-based chemotherapy, and 3.6 months with non-platinum chemotherapy (P < .001). Median PFS was 5.3 months, 5.6 months, and 2.6 months, respectively (P < .001).

Compared with platinum-based chemotherapy, chemoimmunotherapy significantly reduced the risk of death (hazard ratio [HR], 0.73; 95% confidence interval [CI], 0.62 to 0.87; P < .001) and disease progression (HR, 0.79; 95% CI, 0.67 to 0.93; P = .006). Non-platinum chemotherapy was associated with significantly worse outcomes, more than doubling the risk of both death (HR, 2.19; 95% CI, 1.84 to 2.61; P < .001) and disease progression (HR, 2.28; 95% CI, 1.91 to 2.72; P < .001).

Thoracic radiotherapy was independently associated with improved OS (HR, 0.57; 95% CI, 0.48 to 0.69; P < .001) and PFS (HR, 0.59; 95% CI, 0.49 to 0.70; P < .001). Among patients with brain metastases, brain radiotherapy was also independently associated with improved OS (HR, 0.47; 95% CI, 0.35 to 0.65; P < .001), although baseline brain metastases alone were not independently prognostic.

Immune-related adverse events occurred in 21.7% of patients treated with chemoimmunotherapy and resulted in treatment discontinuation in 28 patients. Development of immune-related adverse events was independently associated with longer OS (HR, 0.67; 95% CI, 0.46 to 0.97; P = .032) and PFS (HR, 0.68; 95% CI, 0.47 to 0.95; P = .035). Importantly, discontinuation of immunotherapy because of immune-related adverse events did not adversely affect survival.

“Chemoimmunotherapy confers a clear OS advantage over conventional chemotherapy in real-world ES-SCLC,” concluded Dr Dimitriou et al. “Our results further highlight the critical importance of multimodal treatments, including brain and thoracic radiotherapy, in further enhancing patient outcomes.”

Source:

Dimitriou K, Shi S, Marginenau A, et al. Chemoimmunotherapy versus chemotherapy for extensive-stage small cell lung cancer in the real-world setting: Retrospective study of 904 patients. Clin Lung Cancer. Published online: June 23, 2026. doi: 10.1016/j.cllc.2026.06.004