Radical thoracic radiotherapy may provide favorable outcomes for stage IV non‐small cell lung cancer

BACKGROUND: This study investigates the outcome of synchronous stage IV non‐small cell lung cancer (NSCLC) patients who received radical thoracic radiotherapy (TRT). METHODS: We retrospectively reviewed the charts of stage IV NSCLC patients treated with TRT between January 2007 and December 2011. Radiotherapy was considered radical if it was the primary therapy with non‐symptom driven intent, or consolidation therapy after initial chemotherapy and the biologically equivalent dose ≥53 Gy halted disease progression. The patients' demographics, disease characteristics, and treatment parameters were uniformly collected. RESULTS: Eighty‐one patients were irradiated with radical intent, including 52% with more than five metastatic lesions. The minimum follow‐up was 31.5 months for survivors. The median overall survival (OS) was 20.8 months, with three and four‐year OS rates of 23% and 18%, respectively. The median progression‐free survival (PFS) was 8.2 months, with one and two‐year PFS rates of 23% and 9%, respectively. Partial response (PR) after TRT and administration of targeted therapy were predictive of longer OS. The factors associated with favorable PFS included earlier local tunor node stage, absence of concurrent chemotherapy, and post‐TRT PR. No correlation was found between the number of metastatic lesions and survival outcome. Incidences of grade ≥2 toxicities in the lung and esophagus were 9% and 26%, respectively. CONCLUSIONS: Radical TRT may result in advantageous outcomes for selected stage IV NSCLC patients, regardless of the number of metastatic foci. Patients who achieved post‐TRT PR attained the best outcomes.