Radiation pneumonitis after repeat stereotactic body radiation therapy for early-stage non-small cell lung cancer: A case series of two patients

Abstract

Introduction: Stereotactic body radiation therapy (SBRT) is a well-established treatment option for patients with early-stage non-small cell lung cancer (NSCLC). We retrospectively identified 82 patients with early-stage NSCLC treated with SBRT at our institution between November 2009 and September 2019. Among these patients, two developed local recurrence or new primary lung cancer and lung metastasis or new primary lung cancer, respectively, and were treated with repeat SBRT. We herein report a case series of two patients with radiation pneumonitis after repeat SBRT. Case Series: Case A was an 80-year-old woman diagnosed with stage I (T1aN0M0) squamous cell carcinoma. She received initial SBRT at an irradiation dose of 48 Gy in 4 fractions at the isocenter. Two years and three months after initial SBRT, the patient was clinically diagnosed with post-SBRT local recurrence or primary lung cancer and, thus, was treated with repeat SBRT at an irradiation dose of 60 Gy in 10 fractions. Six months later, the patient developed grade 5 radiation pneumonitis. Case B was an 89-year-old man diagnosed with stage I (T1cN0M0) adenocarcinoma. He received initial SBRT at an irradiation dose of 48 Gy in 4 fractions at the isocenter. Three years and six months after initial SBRT, the patient was clinically diagnosed with post-SBRT lung metastasis or primary lung cancer and, thus, was treated with repeat SBRT at an irradiation dose of 50 Gy in 4 fractions. Six months later, the patient developed grade 3 radiation pneumonitis. Conclusion: Caution is needed when performing repeat SBRT.