Purpose: A comparison of treatment outcomes in response to various methods of radiotherapy for superficial esophageal cancer (SEC) was carried out for a large series of patients.
Methods and materials: During the period from March 1987 to November 1998, 147 patients with superficial esophageal cancer received definitive radiation therapy at nine radiotherapy institutions in Japan. Fifty-five patients were treated with external radiation therapy alone, 69 with high-dose-rate intracavitary radiation therapy with or without external radiation therapy, and 23 with low-dose-rate intracavitary radiation therapy and external radiation therapy.
Results: The 5-year survival rates for mucosal and submucosal cancer patients were 62% and 42%, respectively. The 5-year cause-specific survival rates for mucosal and submucosal cancer patients were 81% and 64%, respectively (p = 0.013). There was no statistically significant difference in the survival rates for either mucosal or submucosal cancer patients between treatment groups. Metastasis was observed only in submucosal cancer patients. Esophageal ulcers developed only in patients who received intracavitary radiation therapy, and were especially common in patients treated with a fraction size of 5 Gy or more.
Conclusions: The use of intracavitary radiation therapy does not influence the survival or local control rate of SEC. Optimal radiotherapy methods for SEC should be determined by a randomized clinical trial.