First-Line Chemoimmunotherapy Plus Consolidative Thoracic Radiotherapy Significantly Improved Intrathoracic Control for Patients With Extensive-Stage Small Cell Lung Cancer

According to results from a retrospective analysis, consolidative thoracic radiotherapy following first-line treatment with chemoimmunotherapy improved intrathoracic control among patients with extensive-stage small cell lung cancer (ES-SCLC). 

“The CREST trial established the benefit of consolidative thoracic radiotherapy following first-line chemotherapy in [ES-SCLC], demonstrating improved 2-year overall survival,” stated Federico Monaca, MD, The Christie NHS Foundation Trust, Manchester, United Kingdom, and coauthors. “However, the role of [thoracic radiotherapy] in the chemoimmunotherapy era remains unclear, as [thoracic radiotherapy] was excluded from registrational trials.” 

In this study, researchers collected data from 336 patients treated with first-line chemoimmunotherapy with (n = 111) or without (n = 225) thoracic radiotherapy. Patients with no radiologic progression at first post-treatment assessment were included in this analysis. The primary end point was intrathoracic recurrence rate. Key secondary end points included progression-free survival (PFS) and overall survival (OS). 

At analysis, the intrathoracic radiologic progression rate was 40.5% in patients who received thoracic radiotherapy and 57.8% in patients who did not receive thoracic radiotherapy (P = .003). In patients with intrathoracic radiologic progression, 24.1% of patients experienced radiologic progression within the radiation field. Patients who underwent thoracic radiotherapy had improved PFS (hazard ratio [HR] 0.89; P = .363) and OS (HR 0.82; P = .142) compared to patients who did not undergo thoracic radiotherapy. 

Multivariate results identified the presence of baseline liver metastases and stable disease after chemoimmunotherapy as independent predictors of shorter PFS. Subgroup analysis results identified higher thoracic radiotherapy doses and no presence of liver metastases as independent predictors of longer PFS. 

“In this series, [thoracic radiotherapy] following [first-line chemoimmunotherapy] significantly improved intrathoracic control, although it did not translate into significantly better survival outcomes,” concluded Dr Monaca et al. “Prospective trials are warranted to evaluate the impact of [thoracic radiotherapy] on quality of life and survival.”

Source: 

Monaca F, Gomez-Randulfe I, Walls G, et al. Consolidation thoracic radiotherapy after chemoimmunotherapy in ES-SCLC: A multicentric retrospective analysis. Eur J Cancer. Published online: June 24, 2025. doi: 10.1016/j.ejca.2025.115592