Postoperative radiotherapy increases locoregional control of patients with stage IIIA non-small-cell lung cancer treated with induction chemotherapy followed by surgery

Purpose: To determine the effectiveness of postoperative radiotherapy (RT) in patients with Stage IIB and Stage IIIA non-small-cell lung cancer (NSCLC) treated with induction chemotherapy followed by surgery. Methods and Materials: We retrospectively reviewed the treatment records of 98 patients (58 men and 40 women; median age 61 years, range 31-91) with Stage IIB and Stage IIIA NSCLC who were treated with induction chemotherapy followed by surgery at our institution between January 1990 and December 2000. Patients were grouped by treatment (chemotherapy/surgery alone vs. chemotherapy/surgery/RT), by disease stage and nodal classification. The rates of local control (LC), disease-specific survival, disease-free survival, and overall survival (OS) were calculated using the Kaplan-Meier method. Results: Of the 98 patients, 40 had Stage IIB and 58 had Stage IIIA. The clinical disease stage and N stage were significantly greater in those patients who underwent RT than in those who did not; however, no statistically significant differences were identified in the additional characteristics between those receiving and not receiving RT within each stage or nodal group. The overall 5-year actuarial LC rate was 81% in the RT group and 54% in the chemotherapy/surgery-alone group (p = 0.07). Postoperative RT significantly improved the 5-year LC rate in patients with Stage IIIA disease (from 35% to 82%, p = 0.01). Postoperative RT did not significantly improve the 5-year OS rate (30% with RT vs. 49% without) for all patients or for patients with Stage IIIA disease. The disease-specific survival and disease-free survival rates did not differ between the treatment groups. Patients who responded to induction chemotherapy had a significantly greater 5-year OS rate (49%) than did those with stable or progressive disease (22%, p = 0.003). Conclusion: Postoperative RT in patients with Stage IIIA NSCLC treated with induction chemotherapy followed by surgery significantly improved LC without improving OS. Significantly improved survival was observed in all patients who responded to induction chemotherapy compared with those with stable or progressive disease.