[Clinicopathologic studies on esophageal carcinoma with basaloid features]

Eight unusual esophageal carcinomas chiefly composed of basaloid cells were defined as "esophageal carcinomas with basaloid features", and analyzed by clinicopathologic findings and immunohistochemical staining with antibodies against S-100, actin, vimentin, and cytokeratin. These tumors were classified into five basaloid-squamous cell carcinomas (BSC), 2 adenoid cystic carcinomas (ACC), and 1 non-small cell type-undifferentiated carcinoma based on the Guidelines for the Clinical and Pathologic Studies on Carcinoma of the Esophagus edited by the Japanese Society for Esophageal Disease. Some histologic patterns of BSC, ACC, or undifferentiated carcinoma were resembled to each others. However, BSC was characterized by solid growth of basaloid cells with microcystic pattern or peripheral palisading arrangement, and it showed simultaneous presence of squamous cell carcinoma or squamous differentiation. In immunohistochemical staining, immunoreactivity for cytokeratin alone was positive in one of five BSCs. On the other hand, ACC showed cribiriform pattern and high mitotic activities, excluding typical cribriform pattern in ACC of the salivary gland. In addition to these features, the presence of foci of squamous cell carcinoma was occasionally found and positive immunoreactivities for S-100 and actin were recognized. Therefore, the immunohistochemical staining was useful for distinction among ACC and other tumors. As to the prognosis, BSC and ACC have been reported that both tumors are aggressive neoplasm with poor prognosis. In our studies, all of 5 patients with BSC were survived more than three years after surgery. In contrast, the patients with ACC or undifferentiated carcinoma died within one year.(ABSTRACT TRUNCATED AT 250 WORDS)