Localization of free secretory component in pleomorphic adenomas of minor salivary gland origin

Secretory component (a glycoprotein) is an antigenically distinct portion of the secretory immunoglobulin A, which has been identified in a number of normal and neoplastic epithelial cells. Localization of secretory component was determined in pleomorphic adenomas of minor salivary gland origin using the four-step peroxidase-antiperoxidase technique. Antiserum that detected only free secretory component (FSC) was used. Staining for secretory component was noted in the epithelium that lined duct-like spaces; but was absent in myoepithelial cells and mucous acini. These findings suggest a role for FSC in evaluating the histogenesis of various salivary gland neoplasms.