Role of Radiation Therapy in the Combined-Modality Treatment of Patients With Extensive Disease Small-Cell Lung Cancer: A Randomized Study

PURPOSE: To investigate the efficacy and toxicity of cisplatin/etoposide (PE) chemotherapy (CHT) with or without accelerated hyperfractionated radiation therapy (ACC HFX RT) and concurrent daily carboplatin/etoposide (CE) in patients with extensive-disease small-cell lung cancer. PATIENTS AND METHODS: A total of 210 patients were treated with three cycles of standard PE. Patients with a complete response (CR) at both the local and distant levels (CR/CR) or a partial response (PR) at the local level and CR at the distant level (PR/CR) received either thoracic ACC HFX RT with 54 Gy in 36 fractions over 18 treatment days in combination with CE followed by two cycles of PE (group 1, n = 55) or an additional four cycles of PE (group 2, n = 54). Patients who experienced less response were treated nonrandomly (groups 3, 4, and 5). All patients with a CR at the distant level received prophylactic cranial irradiation. RESULTS: For 206 assessable patients, the median survival time (MST) was 9 months and the 5-year survival rate was 3.4%. Patients in group 1 had significantly better survival rates than those in group 2 (MST, 17 v 11 months; 5-year survival rate, 9.1% v 3.7%, respectively; P = .041). Local control was also better in group 1, but the difference was only marginally not significant (P = .062). There was no difference in distant metastasis-free survival between groups 1 and 2. Acute high-grade toxicity was higher in group 2 than in group 1. CONCLUSION: The addition of ACC HFX RT to the treatment of the most favorable subset of patients led to improved survival over that obtained with CHT alone.