PURPOSE The present intergroup phase III randomized study compared combined chemotherapy (CT) plus radiotherapy (RT) treatment versus RT only in patients with locally advanced esophageal cancer. MATERIALS AND METHODS Two courses of chemotherapy during 50 Gy RT followed by additional two courses of the same CT, versus 64 Gy RT alone were investigated. CT consisted of cisplatin 75 mg/m2 on day 1 [corrected] and fluorouracil (5FU) 1,000 mg/m2/d on days 1 to 4 every 4 weeks with RT and every 3 weeks post-RT. The main objective of the study was to compare overall survival between the two randomized treatment groups. Patients were stratified by tumor size, histology, and degree of weight loss. RESULTS Sixty-two assessable patients were randomized to receive RT alone, and 61 to the combined arm. Patients characteristics were as follows: squamous cell cancer, 90% versus 85%; weight loss greater than 10 lb, 61% versus 69%; and tumor size, > or = 5 cm, 82% versus 80% on the RT and CT-RT arms, respectively. Systemic side effects, which consisted of nausea, vomiting, and renal and myelosuppression, occurred more frequently on the combined arm, while local side effects were similar in both groups. With a minimum follow-up time of 5 years for all patients, the median survival duration was 14.1 months and the 5-year survival rate was 27% in the combined treatment group, while the median survival duration was 9.3 months with no patients alive at 5 years in the RT-alone group (P < .0001). Additional patients (69) were treated with the same combined therapy and were analyzed. The results of the last group confirmed all of the results obtained with combined CT-RT in the randomized trial, with a median survival duration of 17.2 months and 3-year survival rate of 30%. CONCLUSION We conclude that cisplatin and 5FU infusion given during and post-RT of 50 Gy is statistically superior to standard 64-Gy RT alone in patients with locally advanced esophageal cancer.