OBJECTIVE The records of 52 patients with inoperable but localized squamous cell carcinomas of the esophagus were reviewed to determine the influence of different treatment modalities on survival, dysphagia and sites of recurrence. METHODS 22 patients were treated by concurrent radio-chemotherapy with cis-platin/5-FU or carboplatin/5-FU; 19 patients by radiotherapy alone; six patients by chemotherapy followed by irradiation and five patients by concurrent radio-chemotherapy with various drugs. External beam radiotherapy consisted of treating the primary lesion (mean dose 53 Gy) and the lymphatic areas (mean dose 31 +/- 26 Gy) at the rate of 2 Gy/day for five days/week. Additional intraluminal high-dose-rate radiotherapy was performed in 13 patients with single fractions of 6 Gy as a boost. Minimum follow-up was twelve months, median follow-up 4.3 years. RESULTS For the whole population a remission rate of 65% (34/52 patients) was achieved (complete remission 18/52 patients = 35%; partial remission 16/52 patients = 31%). Relief of dysphagia accompanied tumor regression. Median survival was eleven months; three-year survival rate 23%; five-year survival rate 7.6%. The analysis of recurrence revealed a high rate of local failures (26/52 patients = 50%) and distant metastases (9/52 patients = 18%). Comparing the different modalities the best results were achieved by concurrent radio-chemotherapy with cis-platin/5-FU or carboplatin/5-FU: Complete remission could be determined in 46% and median survival was 14.9 months. Additional intracavitary radiotherapy resulted in a slightly better local control rate (54% vs. 46%) and three-year-survival rate (30% vs. 20%) compared to external beam irradiation alone. CONCLUSIONS Concurrent radio-chemotherapy with cis-platin/5-FU is superior to other treatment modalities in inoperable carcinoma of the esophagus. Additional intraluminal radiotherapy may increase local control rate.