Long-term outcomes after salvage radiotherapy for postoperative locoregionally recurrent non-small-cell lung cancer

PURPOSE: The outcomes and toxicities of locoregionally recurrent non-small-cell lung cancer (NSCLC) patients treated with curative radiotherapy were evaluated in the modern era. MATERIALS AND METHODS: Fifty-seven patients receiving radical radiotherapy for locoregionally recurrent NSCLC without distant metastasis after surgery from 2004 to 2014 were reviewed. Forty-two patients were treated with concurrent chemoradiotherapy (CCRT), and 15 patients with radiotherapy alone. The median radiation dose was 66 Gy (range, 45 to 70 Gy). Lung function change after radiotherapy was evaluated by comparing pulmonary function tests before and at 1, 6, and 12 months after radiotherapy. RESULTS: Median follow-up was 53.6 months (range, 12.0 to 107.5 months) among the survivors. The median overall survival (OS) and progression-free survival (PFS) were 54.8 months (range, 3.0 to 116.9 months) and 12.2 months (range, 0.8 to 100.2 months), respectively. Multivariate analyses revealed that single locoregional recurrence focus and use of concurrent chemotherapy were significant prognostic factors for OS (p = 0.048 and p = 0.001, respectively) and PFS (p = 0.002 and p = 0.026, respectively). There was no significant change in predicted forced expiratory volume in one second after radiotherapy. Although diffusing lung capacity for carbon monoxide decreased significantly at 1 month after radiotherapy (p < 0.001), it recovered to pretreatment levels within 12 months. Acute grade 3 radiation pneumonitis and esophagitis were observed in 3 and 2 patients, respectively. There was no chronic complication observed in all patients. CONCLUSION: Salvage radiotherapy showed good survival outcomes without severe complications in postoperative locoregionally recurrent NSCLC patients. A single locoregional recurrent focus and the use of CCRT chemotherapy were associated with improved survival. CCRT should be considered as a salvage treatment in patients with good prognostic factors.