Histochemistry of human salivary gland tumors

Enzyme Histochemistry and its Application to the Study of the Mixed Tumors of the Salivary Glands

The activity of several hydrolytic (acid and alkaline phosphatase, ATP-ase) and oxidative (lactic, succinic, isocitric, glutamic, ((-glycerophosphate, glucose-6-phosphate and β-hydroxybutyrate dehydrogenases, NADH2 and NADPH2 tetrazolium reductases) enzymes has been studied using histochemical methods in four mixed tumors (pleomorphic adenomas) of human salivary glands: one of epithelial type, one of myxoid and chondroid type and two composed of patches of epithelial cells set in a myxoid stroma. Acid phosphatase showed little activity and alkaline phosphatase and ATP-ase none at all, either in the epithelial and in myxochondroid areas. However, epithelial areas contained clumps of cells strongly reactive for alkaline phosphatase and ATP-ase, sometimes arranged in a duct-like pattern around a homogeneous intercellular substance, also strongly reactive. Of the oxidative enzymes, NADH2-diaphorase and lactic dehydrogenase were strongly active, NADPH2-diaphorase and isocitric dehydrogenase were moderately so and the other dehydrogenases poorly active. There were no detectable differences in enzyme activity pattern between epithelial and myxoid or chondroid areas of the mixed tumors. In general the level of activity of the oxidative enzymes in the mixed tumors was intermediate between that of the acinar cells and that of the cells of the striated excretory ducts of the salivary glands.

Immunohistological study of the epithelial components of Warthin's tumor

In order to gain insight into the origin of Warthin's tumor, 10 cases of Warthin's tumor were compared immunohistologically with macroscopically and microscopically normal areas of the same glands, using 6 types of functional markers; carcinoembryonic antigen, secretory component, lactoferrin, keratin, S-100 protein and glial fibrillary acidic protein. It was shown that in normal parotid glands, the cells of acini, the intercalated ducts, the striated ducts, and the excretory ducts, as well as myoepithelial cells differed from each other in intensity and distribution of reaction products with antisera against those markers. Although the differences were rather subtle, the results suggested that those markers could differentiate the cell types of the salivary glands. In Warthin's tumors with double-layered tumor epithelia, the staining characteristics of the luminal and basal epithelia differed from each other. Epithelial cells on the luminal side showed immunological characteristics similar to striated duct cells of the parotid gland, while those of the basal side had characteristics similar to those of basal cells of the excretory duct. It is therefore suggested that the epithelia of Warthin's tumor may show differentiation into 2 different cell types.

Ultrastructural cytochemistry of phosphatases in the ductal component of pleomorphic adenoma of human parotid and submandibular salivary glands

Some ductal cells of pleomorphic adenomas showed evidence of secretory activity, with apical secretory granules, thiamine pyrophosphatase activity in the Golgi apparatus, and acid phosphatase activity in GERL-like structures and in immature secretory granules. Alkaline phosphatase activity was demonstrated rarely at the luminal plasma membrane and in intracellular vesicles, suggesting resorptive activity. ATPase reaction product was associated with contiguous surfaces of tumour cells, particularly of those cells adjacent to the basement membrane, these latter cells apparently differentiating in a different manner to the luminal cells. A comparison of luminal ductal cells of the tumours with normal salivary glands revealed most similarity with intercalary ductal cells.

Oncocytic neoplasms of salivary glands: a report of fifteen cases including two malignant oncocytomas

Fifteen oncocytic (oxyphilic granular cell) neoplasms of the salivary glands collected from three large university medical centers are presented. The histologic and ultrastructural criteria that characterize oncocytes are presented and electron micrographs of two of our cases are discussed. Included in the series are 10 benign oncocytomas, two malignant oncocytomas and three benign, oncocytic pleomorphic adenomas. The clinical and pathologic features of benign oncocytomas are reviewed, with special attention to the variety of gross and microscopic changes present. The literature on malignant oncocytomas is critically reviewed, diagnostic criteria are evaluated, and a unique case is discussed in detail. Reference is made to a group of neoplasms that we designate as benign locally aggressive oncocytomas. The problem of differential diagnosis between oncocytoma and bening, oncocytic pleomorphic adenoma is considered.

Parotid saliva enzymes in Down's syndrome

The parotid saliva in persons with Down's syndrome was analyzed for three enzymes: acid phosphatase, nonspecific esterase, and amylase. The results have shown a statistically significant elevation of esterase activity in persons with Down's syndrome whereas no statistical differences were observed with the other enzymes. The current investigation has provided further insight into salivary gland metabolism and may have yielded some information pertaining to the genetic control of the processes regulating the electrolyte concentration of human saliva.