Clinical Outcomes of Single Dose Stereotactic Radiotherapy for Lung Metastases

IntroductionStereotactic body radiation therapy is an emerging noninvasive technique for the treatment of oligometastatic cancer. The use of small numbers of large doses achieve a high percentage of local control. The aim of this study was to evaluate the efficacy and tolerability of SBRT for the treatment of lung metastases in a cohort of patients treated between 2008 and 2012 at our institution.Patients and MethodsA total of 66 patients with oligometastatic lung tumors (single pulmonary nodules in 40 patients; 61%) were included in the study. SBRT was performed with a stereotactic body frame and a 3-D conformal technique. Forty-nine central tumors received 23 Gy in a single fraction and 54 peripheral tumors received a dose of 30 Gy in a single fraction. The primary end point was local control; secondary end points were survival and toxicity.ResultsMedian follow-up was 15 months (range, 3-45 months). Local control rates at 1 and 2 years were 89.1% and 82.1%, overall survival rates were 76.4% and 31.2%, cancer-specific survival rates were 78.5% and 35.4%, and progression-free survival rates were 53.9% and 22%, respectively. Median survival time was 12 months, and median progression-free survival time was 10 months. Toxicity profiles were good, with 2 cases of Grade 3 toxicity (pneumonitis).ConclusionSBRT is an effective and safe local treatment option for patients with lung metastases, although it remains investigational; longer follow-up to confirm results is required.