Monomorphic adenomas of the major salivary glands: clinicopathological study of 44 cases. We report 44 cases of monomorphic adenoma (MA) of the major salivary glands observed during the years 1979-1989. All of these tumours were reviewed and classified on the basis of the World Health Organisation (WHO) criteria. Histological type, site, sex and age were considered. 34 cases of adenolymphoma were observed, all of them located in the parotid glands; 10 MA without lymphoid stroma were located in both parotid and submandibular glands. Distinctive histological and clinico-pathological features of the latter group of tumours are discussed, as well as the diagnostic criteria in distinguishing these tumours from pleomorphic adenoma and adenoid-cystic carcinoma. 