[A consideration of the definition of early esophageal cancer on the basis of clinicopathologic viewpoint].

A review of 323 patients with carcinoma of the esophagus disclosed 50 cases (15.5%) with glandular and/or mucus-secreting components, in addition to the ordinary component of squamous cell carcinoma. These tumors could be grouped into three type according to representative histologic features of glandular and mucus-secreting portions: glandular type (28 cases), cribiform type (14 cases), and mucoepidermoid type (8 cases). The histologic features of the three types were reminiscent of those of adenocarcinoma, adenoid cystic carcinoma, and mucoepidermoid carcinoma of salivary glands, respectively. Moreover, areas showing glandular or mucus-secreting differentiation were in greater part located in the submucosa and the lamina propria mucosae, thereby suggesting that such differentiation had arisen in the esophageal glands or their ducts. From these findings, in addition to intraepithelial and mucosal carcinomas, carcinoma restricted to the submucosal layer without lymph node metastases should be also defined as "early" esophageal cancer and definition of it according to the existing Guide Lines for the Clinical and Pathologic Studies on Carcinoma of the Esophagus is thought to be adequate at present.