3682 - Efficacy and Safety of Various Regimens in Small Cell Lung Cancer Patients Who Progressed from Limited Stage to Extensive Stage
Presenter(s)
M. Yu1, X. Liu2, Z. Wei3, W. Cui3, Y. Li3, K. Zhao3, Y. Chen4, H. Zhao2, and X. Meng5; 1Shandong Cancer Hospital and Institute, Shandong First Medical University, Shandong Academy of Medical Sciences, Department of Radiation Oncology, Jinan, Shandong, China, 2Shandong Cancer Hospital and Institute, Shandong First Medical University and Shandong Academy of Medical Sciences Department of Radiation Oncology, Jinan, Shandong, China, 3Cancer Center, Shandong University, Department of Radiation Oncology, Shandong Cancer Hospital and Institute, Shandong First Medical University and Shandong Academy of Medical Sciences, Jinan, Shandong, China, 4Department of Radiation Oncology, Shandong Cancer Hospital and Institute, Shandong First Medical University and Shandong Academy of Medical Sciences, Jinan, China, 5Shandong Cancer Hospital and Institute, Shandong First Medical University, Shandong Academy of Medical Sciences, Department of Radiation Oncology,, Jinan, Shandong, China
Purpose/Objective(s): There is a lack of research on patients with limited-stage small cell lung cancer (LS-SCLC) that had progressed to extensive stage. This study aimed to evaluate the efficacy and safety of various regimens in patients with LS-SCLC who had progressed to extensive-stage small cell lung cancer (ES-SCLC).
Materials/Methods: This study retrospectively analyzed the patients with LS-SCLC that had progressed to extensive stage after receiving standard chemoradiotherapy. Univariate and multivariate analyses were performed to identify the prognostic factors. The primary endpoints were progression-free survival (PFS) and overall survival (OS). Secondary study endpoints were adverse reactions.
Results: A total of 378 patients enrolled from January 1, 2018, through December 1, 2024, were divided into two groups: the immunotherapy group (45.8%) and the non-immunotherapy group (54.2%). Patients who achieved CR/PR during limited-stage treatment had longer OS (14.8 months vs. 11.2 months, HR=0.71, 95%CI 0.54-0.92, p<0.05) and PFS (5.8 months vs. 4.9 months, HR=0.76, 95%CI 0.59-0.97, p<0.05) than those with SD/PD. Treatment regimens containing platinum-based drugs (EP/EC) during the extensive stage were superior to those without platinum-based drugs (17.1 months vs. 11.7 months, HR=0.70, 95%CI 0.53-0.91, p<0.05). The median overall survival (mOS) and the median progression-free survival (mPFS) in the immunotherapy group were longer than those in the non-immunotherapy group (16.1 months vs. 11.9 months, HR=0.61, 95%CI 0.47-0.78, p<0.05; 5.4 months vs. 5.1 months, HR=0.72, 95%CI 0.57-0.91, p<0.05, respectively). Immunotherapy combined regimens demonstrated clinical benefit in patients with treatment-free interval (TFI) < 6 months (14.9 months vs. 10.0 months, HR=0.62, 95%CI 0.46-0.83, p<0.05). The EP/EC regimen showed significant benefit only in the TFI = 3 months subgroup (17.7 months vs. 12.5 months, HR=0.64, 95%CI 0.45-0.90, p<0.05), with no benefit observed in the TFI < 3 months subgroup. The immunotherapy group exhibited a higher overall incidence of elevated ALT/AST levels and thyroid dysfunction compared to the non-immunotherapy group.
Conclusion: Our findings indicate that combined immunotherapy regimens significantly prolong survival in patients with small cell lung cancer progressing from the limited stage to the extensive stage. Furthermore, achieving CR/PR during limited stage treatment and the use of platinum-based therapy in the extensive stage were both associated with improved prognosis.