[Phase III clinical trial for esophageal cancer using radiotherapy]

Phase III clinical trials using radiotherapy for esophageal cancer are reviewed. Concerning preoperative radiotherapy, results of 6 of 7 clinical trials failed to show its usefulness. Two randomized trials evaluating postoperative radiotherapy were performed. Both of them, however, proved negative. Chemoradiation has been used for inoperable esophageal cancer instead of radiotherapy alone. Combined modality therapy with radiation and Bleomycin was found to be useless. In early 1980, multiple drugs including 5-FU and radiation were compared with radiation alone, and 2 out of 3 clinical trials were positive. CDDP was then included in the chemoradiation regimen, and CDDP+5-FU and radiotherapy were found to yield survival benefits. Preoperative chemoradiation was tested in 4 randomized clinical trials. However, the results were entirely negative. Based on the results of these clinical trials, problems of treatment strategy for esophageal cancer in Japan are discussed in this article.