[Adenocarcinoma of the salivary glands. The pathohistology and subclassification of 77 cases].

Seventy-seven adenocarcinomas of the salivary glands recorded in the Salivary Gland Register between 1965 and 1984 were analysed and classified histopathologically. The following results were obtained: 1. 2% of all salivary gland tumours and 10% of all malignant epithelial salivary gland tumours were allotted to the group of adenocarcinomas. The age peak lies in the 7th to 8th decade. 60% occurred in women, 58.5% were localized to the parotid gland, 28.5% to the minor salivary glands (palate, lips, and cheek), 11.5% to the submandibular gland and only 1.5% to the sublingual gland. 2. Solid, tubular and papillary adenocarcinomas can be distinguished. Additional criteria are microcysts, mucus production and grade of differentiation. 3. The solid adenocarcinoma (13%) is predominantly localized in the parotid gland and characterized by a low differentiation, invasive growth and metastases. 4. 62.5% of tubular adenocarcinomas (52%) are localized in the parotid gland, 27.5% to the minor salivary glands and 10% to the submandibular gland. Most of the tumours are highly differentiated. A distinct mucus production is present in 40% of the cases. Microcysts are very frequent. 5. Papillary adenocarcinomas (28.5%) are localized in almost 50% of cases to the minor salivary glands, 45% to the parotid and only 5% to the submandibular gland. Microcysts and mucus production can be observed in 50% of the cases. 6.5% of the cases have a mixed tubular papillary structure. 6. In differential diagnosis, thyroid gland carcinomas and metastases of other adenocarcinomas must be distinguished, the former by negative result of the thyroglobulin reaction, and absent mucus production. 7. Adenocarcinomas arise from the salivary duct system. Solid or tubular adenocarcinomas imitate stages of the embryonal development of the salivary ducts.