Carcinosarcoma of the esophagus: a report of two cases.

Among 137 cases of esophageal neoplasms surgically treated at Kobe City General Hospital from 1983 to 1990, there were two patients with a huge polypoid lesion identified as carcinosarcoma by light microscopic examination, both of whom underwent radical resection and esophagogastrostomy. Microscopic examination of the resected specimens revealed the tumors to be composed of carcinomatous and sarcomatous elements. Additional immunohistochemical examination disclosed keratin-positive cells in the carcinomatous element and vimentin-positive cells in the sarcomatous element. In case 1, keratin-positive cells were also found in the sarcomatous element, which suggested that the sarcomatous cells were derived from epithelial cells. Despite the huge size of the tumors, the depth of invasion to the esophageal wall was limited to the mucosal layer in case 1 and the submucosal layer in case 2, and there has been no evidence of recurrence in either case since surgery.