2418 - The Role of Radiotherapy in Unresectable Primary Pulmonary Sarcoma: A Multicenter Study
Presenter(s)
A. Liu1, X. Yin2, J. Wen3, J. Peng4, K. Zhao3, Z. Huang5, H. Feng6, and X. Meng7; 1School of Clinical Medicine, Shandong Second Medical University, Weifang, China, 2Department of Radiation Oncology, Shandong Cancer Hospital and Institute, Shandong First Medical University and Shandong Academy of Medical Sciences, Jinan, China, 3Shandong Cancer Hospital and Institute, Shandong First Medical University and Shandong Academy of Medical Sciences Department of Radiation Oncology, Jinan, Shandong, China, 4Department of Radiation Oncology, Shandong Cancer Hospital and Institute, Shandong First Medical University and Shandong Academy of Medical Sciences, Jinan, Shandong, China, 5Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan, China, 6Department of radiation oncology, The Affiliated Hospital of Qingdao University, Qingdao, China, 7Cheeloo College of Medicine, Shandong University, Jinan, Shandong, China
Purpose/Objective(s): Primary pulmonary sarcoma is a rare malignant tumor that lacks specific treatment options. In particular, for the evaluation of the efficacy of radiation therapy (RT), data on the effectiveness of RT are limited. This study aims to evaluate the efficacy of radiotherapy in the treatment of pulmonary sarcoma.
Materials/Methods: We retrospectively analyzed 47 non-surgical primary pulmonary sarcoma patients from three Chinese tertiary centers (2015–2023), stratified into RT (n=26) and non-RT (n=21) groups. In the RT group, 15 patients received definitive RT, while 11 received palliative RT. Systemic therapies included anthracycline-ifosfamide chemotherapy and chemotherapy combined with immunotherapy/targeted agents. Tumor response was assessed per RECIST 1.1, with local control defined as non-progression of irradiated lesions. Kaplan-Meier method was used for survival analysis
Results: The RT group demonstrated a significantly prolonged median progression-free survival (PFS) compared to the non-RT group (10.2 vs. 4.9 months, p=0.04). The ORR was 38.5% in the RT group, including 1 complete response (CR). In contrast, the non-RT group achieved an ORR of 28.6%, with no CR observed (p=0.42). Among 31 irradiated lesions with evaluable local control data, the local control rate was 88%. Additionally, patients in the RT group who received Anlotinib showed a better survival trend, with a median PFS of 12.1 months.
Conclusion: Radiotherapy significantly improves PFS and provides robust local tumor control in unresectable PPS, supporting its integration into multimodal management. Notably, 1 patient achieved CR after definitive RT, demonstrating the potential for durable remission in selected cases. While ORR differences were non-significant, the survival benefit and observed CR underscore RT’s role in delaying disease progression and inducing deep responses. Further studies are warranted to optimize RT dose-fractionation and validate synergies with targeted therapies like anlotinib.