The case of a 51-year-old man, complaining of a sense of pressure on his chest, is reported. Tests led to a diagnosis of a cancer in the midesophagus and a subtotal esophagectomy was performed. The tumor was found to be a protruded type, 8.5 X 7.0 cm in size. A histologic diagnosis revealed it to be a small cell anaplastic carcinoma. The tumor cells were found negative in a Grimelius staining and did not contain hormones such as ACTH. Some cytokeratins, however, were detected by an immunohistochemical examination, Cancer invasion into the adventitia was seen, though no lymph node metastasis or a distant metastasis was shown. Six months after operation, a recurrence in the mediastinum and in the distant lymph nodes was found. Chemotherapy and irradiation were found to be useful, and the postoperative survival period was 25 months.