Granulomatous sialadenitis of the major salivary glands. A clinicopathological study of 57 cases.

Fifty-seven of 469 major salivary glands excised for various reasons were found to contain granulomas. The aetiologies were tuberculosis (eight parotid, one sublingual), sarcoidosis (two parotid), calculous duct obstruction (34 submandibular), carcinomatous duct obstruction (four submandibular, one sublingual) and undetermined (four submandibular, three parotid). The tuberculous glands showed caseation in the majority of cases but two cases consisted predominantly of discrete granulomas with minimal necrosis. The sarcoid granulomas were typically non-caseating but a few were centrally necrotic. The cases of calculous and carcinomatous duct obstruction contained single to multiple small granulomas which contained mucin and were related to ruptured ducts. It is suggested that the frequency of calculi and the mixture of serous and mucous acini in the submandibular gland account for the distribution of obstructive granulomas. This study establishes calculous sialadenopathy as a major cause of granulomatous sialadenitis.