[Swellings of the cheek from sialosis (author's transl)]

The term sialosis was introduced by Rauch (1956) and was associated with a symmetrical, painless, recurrent enlargement of the salivary glands. Included among the sialoses were non-inflammatory and inflammatory diseases of the salivary glands. A more recent definition still in use today was made by Seifert (1960) and includes disturbances in metabolism and secretion of the parotid gland. The term sialosis was also recommended by the World Health Organization (Thackray and Sobin, 1972) to replace the descriptive term "asymptomatic salivary enlargement." In addition to inflammatory diseases and tumors of the salivary glands, sialosis is the most common disease of salivary tissue recorded at the Institute for Pathology, University of Hamburg. In 50% of patients with sialosis, a syntropic occurrence of other diseases can be found which can be further classified as endocrine, dystrophic-metabolic, and neurogenic sialoses. All clinical types of sialosis are represented by only one morphological pattern: enlarged acinar cells with either a granular pattern, a numerical increase in secretory granules or a vacuolar transformation of the cytoplasm; degenerative changes are seen in myoepithelial cells and the autonomic nervous system. Three types of sialosis can be further distinguished by the electron density of the acinar granules. These are granular, vesicular or mixed. However, there is no correlation between the clinical and morphological forms of sialosis. Experimental destruction of the sympathetic nervous system results in tissue changes which are similar to sialosis. These ultrastructural alterations are interpreted as a disturbance of secretion, and suggest that degeneration of the autonomic nervous system is the common pathogenic principle in all types of sialosis.