ESTRO 2025 - Abstract Book

S1303

Clinical - Lung

ESTRO 2025

Conclusion: The findings of this retrospective study indicate that RA Dmax may influence overall survival in patients receiving PORT. Restricting the RA Dmax dose to under 43.6 Gy and omitting elective nodal irradiation may improve survival outcomes in this patient population.

Keywords: Lung cancer, PORT, cardiac substructures

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Mini-Oral A Randomized , Phase II Study of Primary Tumor Radiotherapy for Non-Small Cell lung Cancer with Malignant Pleural Effusion （ NCT 03987087 ） Qingsong Li, Weiwei Ouyang, Shengfa Su, Zhu Ma, Yichao Geng, Cheng Hu, Wengang Yang, Xiaxia Chen, Yinxiang Hu, Bing Lu Department of Thoracic Oncology, Affiliated Hospital of Guizhou Medical University, guiyang, China Purpose/Objective: The impact of primary tumour radiotherapy for non-small-cell lung cancer (NSCLC) with malignant pleural effusion (MPE)(MPE-NSCLC) is unclear. The purpose of this research was to assess the efficacy and safety of primary tumor radiotherapy in patients with MPE-NSCLC. Material/Methods: We conducted a prospective, phase II clinical trial enrolling MPE-NSCLC patients. Systemic drug treatment is prescribed according to authoritative guidelines ， including targeted therapy ， systemic chemotherapy ， immunotherapy ， and so on.Intrathoracic chemotherapy with cisplatin (80-100 mg/m2, every 21-28 days) was permitted but not mandatory for any patient. Radiotherapy to metastatic lesions was appropriate for any patient, depending on clinical necessity ， such as ， brain metastasis ， bone metastasis with cancer pain ,and so on. After MPE was limited through treatment ， patients were randomized in a 1:1 ratio to receive systemic drug treatment plus primary tumor radiotherapy （ Arm A ） or systemic drug treatment without primary tumor radiotherapy （ Arm B ） . The primary endpoint was progression-free survival （ PFS ） .The Kaplan-Meier method was used for survival analysis and the log-rank test was used for between-group analysis.This study is registered with ClinicalTrials.gov, number NCT03987087 ） .

Results: