Tumor antigens in neoplasms of the human parotid gland

In a collection of parotid gland tumors the presence of different antigens was studied by immuno-histochemical methods. The series was composed of different tumors: adeno- and cystadenocarcinomas, adenoid-cystic carcinomas, salivary duct carcinomas, mucoepidermoid tumors, squamous cell carcinomas and anaplastic carcinomas. The following substances were studied: 1. Substances normally present in salivary glands like lysozyme and lactoferrin. 2. Oncofetal antigens: carcinoembryonic antigen (CEA) and alpha-fetoprotein (AFP). 3. Different classes of intermediate-sized filaments: prekeratin and vimentin. The presence of lactoferrin and carcinoembryonic antigen could be demonstrated in the glandular differentiated tumors, whereas the squamous cell carcinomas, although CEA positive, were lactoferrin negative. The anaplastic carcinomas were negative for lactoferrin and CEA. Lysozyme and AFP could not be demonstrated in the tumors of our material. Mucoepidermoid tumors and squamous cell carcinomas were clearly positive for prekeratin filaments whereas the stromal part showed a vimentin filaments in the cytoplasm of fibroblasts. These antigens provide a useful tool to distinguish between the epithelial and mesenchymal tumors.