Early-Stage Non-Small Cell Lung Cancer Stereotactic Body Radiation Therapy (SBRT) Outcomes in an Equal Access Military Setting.

Introduction Lung stereotactic body radiation therapy (SBRT) is a first-line treatment for early-stage lung cancer in non-surgical candidates or those who refuse surgery. We compared our institutional outcomes from a unique patient population with decreased barriers to care with a recently published prospective series. Materials and methods  We retrospectively reviewed all patients who received definitive lung SBRT at the Walter Reed National Military Medical Center from 2015 to 2020. All patients underwent a positron emission tomography-computed tomography (PET-CT) and all were presented at a multidisciplinary tumor board. Patients were treated on a Trubeam linear accelerator (LINAC)-based system with daily cone-beam CT. The results were qualitatively compared to outcomes from prospective studies including RTOG 0236 and RTOG 0618. Results A total of 105 patients with 114 lesions were included. Median age was 77 years and 54.7% had ≥ 40-pack year smoking history. 36.8% did not have pathologic confirmation. With a median follow-up of 24 months, three-year local control (LC), disease-free survival (DFS) and overall survival (OS) rates were 92.4%, 81.0%, and 80.0%, respectively. Rates of Grade 1 and 2 toxicity were 21.9% and 6.7% and no patients experienced Grade ≥ 3 toxicity. Conclusions In our military setting with universal coverage and routine multidisciplinary care, lung SBRT provides outcomes comparable to prospective studies conducted at high-volume academic centers. More than one-third of patients were treated empirically without pathologic confirmation of disease, demonstrating a difference between clinical trials and community practice. Further investigation is warranted to integrate multidisciplinary management and achieve equal access to care to bridge existing health disparities in the community setting.