Twice daily irradiation increases locoregional control in patients with medically inoperable or surgically unresectable stage II-IIIB non-small-cell lung cancer

Purpose: To evaluate the effect of q.d. or b.i.d. radiotherapy (RT) on the outcome of patients with locally advanced non-small-cell lung cancer. Methods and Materials: We retrospectively reviewed the outcome of 261 patients with medically inoperable or surgically unresectable Stage II-IIIB non-small-cell lung cancer, who were treated with combined modality cisplatin-based chemotherapy and RT. Chemotherapy was administered either sequentially or concurrently with thoracic RT. The median follow-up was 18 months (range 2-92). Treatment groups included sequential chemotherapy and q.d. RT (n = 109), concurrent chemotherapy and q.d. RT (n = 48), and concurrent chemotherapy and b.i.d. RT (n = 104). Of the 261 patients, 97% had a Karnofsky performance score ≥80, and 86.2% had ≤5% weight loss in the 3 months before diagnosis; 66.7% had nonsquamous cell histologic features. All but 8 patients had Stage IIIA-B disease. Results: The 2- and 5-year locoregional control rate was 42.4% and 25.7% for the q.d. group and 70.6% and 45.8% for the b.i.d. group, respectively (p = 0.0001). The 2- and 5-year disease-free survival rate was 26.7% and 6.5% for the q.d. group and 39.6% and 27.3% for the b.i.d. group, respectively (p = 0.0114). The corresponding overall survival rates were 35.9% and 9.4% for the q.d. group and 38.7% and 26.1% for the b.i.d. group. No difference was found in the rate of distant metastasis between the 2 groups. Multivariate analysis indicated that b.i.d. RT was a favorable prognostic factor for locoregional control and disease-free survival. Conclusion: RT b.i.d. significantly improved locoregional control and disease-free survival compared with RT q.d. in patients with Stage IIIA-B non-small-cell lung cancer.