Hyperthermia is effective for the treatment of cancer when applied concomitantly with chemotherapy and irradiation. However, it is difficult to heat deep portions of the body including the esophagus. Cancer of the esophagus still poses considerable treatment problems, with a poor 5-year survival rate after surgery, an even worse outlook after radiation and surgery, and a not very satisfactory response to chemotherapy. We, therefore, devised an electrode for radio frequency, and we have been successfully using this electrode in the treatment of esophageal cancer. The 5-year survival rates of patients with esophageal cancer, given either preoperative hyperthermochemoradiotherapy or chemoradiotherapy, were 43.2 and 14.7%, respectively. Immediate improvement of subjective complaints and decrease or elimination of the cancer lesion are so distinct that this treatment, by means of an endotract antenna, shows promise as a modality for esophageal lesions.