Phase II trial of hyperfractionated accelerated radiation therapy for nonresectable non-small-cell lung cancer: Results of Eastern Cooperative Oncology Group 4593

Purpose: To assess the feasibility, toxicity, and efficacy of hyperfractionated accelerated radiation therapy (HART) for non-small-cell lung cancer (NSCLC). Patients and Methods: Thirty patients from six institutions with stage IlIa or IIIB NSCLC were enrolled between November 1993 and August 1995. Radiation therapy (total dose, 57.6 Gy in 36 fractions) was delivered over 15 days with the use of three daily fractions with a 4- hour interval between fractions and an 8-hour interval between on-cord fields. Patients were not treated on weekends. Results: Twenty-eight patients (93%) completed radiation therapy. Treatment-related toxicities of grade 3 or greater included esophagitis in six patients and grade 3 skin reaction in three patients. The overall objective response rate was 54%, and the response rate within the radiation field was 64%. With a minimum follow-up of 19 months in surviving patients, the median survival and 1-year survival rate are 13 months and 57%, respectively. The median relapse-free survival and 1- year relapse-free survival rate are 7 months and 23%, respectively. No transverse myelitis or late toxicities of grade 4 or greater have been observed. Conclusion: HART, delivered to a total dose of 57.6 Gy over 15 total days, is practical and well tolerated. Survival appears similar to that seen with modern combined modality regimens. A phase III trial is under way.