Stereotactic Body Radiotherapy for Medically Inoperable Malignant Lung Tumor with Respiratory Gating: A Retrospective Observational Study from Tertiary Cancer Center

A BSTRACT Background: In early-stage non-small-cell lung cancer (NSCLC) and oligometastatic lung disease, surgical resection is the standard of the treatment. For those medically inoperable diseases, the current standard of care is stereotactic body radiotherapy (SBRT). Indian data regarding the actual outcome of both treated with SBRT are limited. Objective: The study aims to describe the demographic and treatment characteristics of patients with early-stage NSCLC and oligometastatic lung disease and assess the outcomes of patients treated with SBRT. Materials and Methods: This retrospective observational study involves patients with medically inoperable early-stage NSCLC and oligometastatic lung disease treated with SBRT at our hospital from January 2015 to December 2023. Data were captured from the electronic medical records of the hospital-based cancer registry, and progression-free survival (PFS) and overall survival (OS) were calculated using the Statistical Package for the Social Sciences software. Results: We included 18 patients in this study. Of 18 patients, 11 patients had Stage 1 medically inoperable early-stage non-small-cell lung (NSCL), and seven patients had medically inoperable oligometastatic lung disease. In early stage medically inoperable NSCL at a median follow-up of 17 months, 2-year local control was 88.9%. The 2-year PFS was 58.3%, and the 2-year OS was 61.7%. Only one patient had radiation acute pneumonitis, which was managed conservatively. No late toxicity was observed. In medically inoperable oligometastatic patients, at a median follow-up of 19 months, 2-year local control is 53.3%. The 2-year PFS was 34.3%, and the 2-year OS was 47.6%. No acute or late toxicity was observed in these patients. Conclusion: Our study shows that lung SBRT for both patients who are medically inoperable with primary NSCL and oligometastatic lung disease is effective and provides reasonable local control and OS in a real-world scenario.