Salivary duct carcinoma: ultrastructural and histogenetic considerations

Two cases of salivary duct carcinoma were examined by light and electron microscopy. Histologically, the tumor presented cribriform and papillary patterns together with comedonecrosis. Electron microscopy revealed duct cells with microvilli, interdigitations, and apical vesicles. No myoepithelial cells were observed. These findings suggest a ductal origin other than from the intercalated duct or its precursor element. The importance of separating the salivary gland adenocarcinomas is discussed.