Statistics on the causes for deaths of 638 patients operated on in our department for resection of cancer of the intrathoracic esophagus (squamous cell carcinoma) during the period from 1959-1979 showed that the major causes for direct operative deaths were pyothorax, pulmonary complications, failure of the sutures, and postoperative hemorrhage. Among operation survivors, recurrence was the most frequent cause of death, responsible for the deaths of as many as 80% of less-than-five year survivors; and recurrence in the cervical, supraclavicular fossa, and superior mediastinal lymph nodes and that in the other organs were the frequent causes for the deaths of two- to three-year survivors. Pulmonary complications were the causes for the deaths of 50%, and recurrence for the deaths of 30% of five- to ten-year survivors. Recurrence in the digestive organs other than the esophagus and cardiovascular diseases were the frequent causes for the deaths of more-than ten-year survivors, while none of these survivors died of recurrence.