Abstract
A case of so-called carcinosarcoma of the esophagus in a 76-year-old man is reported. The tumor with ulceration (Borrman III type) was grossly found at Im-portion of the esophagus but not a polypoid lesion. Subtotal esophagectomy was performed surgically. With hematoxylin-eosin staining, the resected specimen revealed poorly differentiated squamous cell carcinoma with pleomorphic cell sarcomatous stroma. To examine the features of sarcomatous lesion, the tumor was stained immunohistochemically with antibodies against keratin (high molecular and low molecular type), epithelial membrane antigen (EMA), α1-antichymotryspin (α1-ACT) and vimentin respectively. The sarcomatous cells of this tumor showed the results of negative staining for keratin, positive staining for EMA, vimentin and α1-ACT, indicating characters of both epithelial and mesenchymal origin. The present case was considered so-called carcinosarcoma (squamous cell carcinoma with pleomorphic cell stroma) which derived from epithelial origin, and it was immunohistochemically suggested that cancer cells obtained a mesenchymal character at the level of intermediate filaments.
