Use of stereotactic body radiation therapy for medically inoperable multiple primary lung cancer

Introduction: To review outcomes of medically inoperable patients treated with stereotactic body radiation therapy (SBRT) for multiple primary lung cancer (MPLC). Methods: We retrospectively reviewed the charts of 10 patients (21 lesions) treated with SBRT for synchronous (seven), metachronous (one) or synchronous/metachronous lung cancers. All patients were male, medically inoperable and had a median age of 66 years. Eight patients had bilateral disease and two had unilateral disease. All patients had a histological diagnosis in at least one of the two lesions and four patients (44.4%) had both lesions biopsied. There were 18 T1 lesions and three T2 lesions. SBRT was in three fractions of 20 Gy or five fractions of 11–12 Gy to each lesion. Results: Mean and median follow up were 18.8 and 15.5 months, respectively. At analysis, six patients (60.0%) are alive, and five of these living patients (83.3%) have no evidence of disease recurrence or progression. Four patients (44.4%) developed distant metastatic disease. Twenty lesions (95.2%) achieved in-field local control. No patients experienced acute pulmonary complications and only two patients (22.2%) experienced late grade I lung toxicity as per the Radiation Therapy Oncology Group toxicity criteria. Conclusion: SBRT for MPLC in medically inoperable patients is a safe, feasible and effective treatment approach.