2436 - Impact of Hepatic Radiotherapy on Survival Outcomes in Small Cell Lung Cancer Patients with Liver Metastases: A Retrospective Study
Presenter(s)
X. Liu1,2, Y. Li2, L. Jiang2, X. Li2, X. Wang2, H. Zhao2, L. Kong2, K. Zhao2, and X. Meng1,2; 1Cheeloo College of Medicine, Shandong University, 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
Purpose/Objective(s): Small cell lung cancer (SCLC) is an aggressive malignancy characterized by early metastatic spread, with hepatic metastases observed in 30%-40% of patients at initial diagnosis. SCLC patients with liver metastasis have the worst prognosis (median overall survival typically <8 months). Emerging evidence in oligometastatic solid tumors suggests that consolidative local therapy can improve survival, yet the role of liver-directed radiotherapy (RT) in SCLC remains undefined. This study aimed to evaluate the clinical benefits of liver-directed RT in SCLC patients with hepatic metastases.
Materials/Methods: We conducted a retrospective analysis of 258 SCLC patients with liver metastases treated between 2019 and 2024. The experimental group (n=129) received stereotactic body radiotherapy (SBRT) or conventional fractionated RT to hepatic lesions, while the control group (n=129) received systemic therapy alone. Propensity score matching balanced baseline characteristics (age, gender, ECOG performance status, previous treatment). Survival outcomes were analyzed using Kaplan-Meier methods and Cox regression models.
Results: The experimental group demonstrated significantly improved median overall survival (OS) (12.63 vs. 5.23 months, p<0.0001, HR = 0.41, 95% CI: 0.31–0.54) compared to controls. The 1-year OS rates for the two cohorts were 50.96% and 17.74%(p<0.0001), respectively. Multivariate analysis confirmed liver RT as an independent predictor for OS (HR 0.36, 95% CI 0.27-0.48). Among 115 patients who underwent post-radiotherapy liver function monitoring, 43 cases (37.4%) exhibited Grade 1 hypoalbuminemia, 11 cases (9.6%) developed Grade 1 transaminase elevation, and 8 cases (7.0%) presented Grade 1 hyperbilirubinemia, as defined by the Common Terminology Criteria for Adverse Events (CTCAE, version 5.0). All biochemical abnormalities did not necessitate treatment discontinuation.
Conclusion: In this retrospective analysis, liver-directed radiotherapy demonstrated a clinically meaningful survival advantage and safety in ES-SCLC patients with hepatic metastases, offering a median OS advantage of 7.4 months. These findings suggest that integrating localized RT into multidisciplinary management may benefit select patients, and prospective validation through randomized trials is urgently needed for further validation.