Adenoid cystic carcinoma of minor salivary gland. Histochemical and electron microscopic studies of cystlike space.

Five cases of adenoid cystic carcinoma of minor salivary glands were studied. The mucoid material in the characteristic cystlike space of this neoplasm was distaseresistant periodic acid-Schiff (PAS)--positive, alcain blue-positive, toluidine blue-positive, and mucicarmine-positive. Verhoeff-Van Gieson's method and Weighert's method did not reveal elastic tissue in the cystlike spaces. Mallory's method revealed that a central core in cystlike spaces was similar in stainability to collagen. Wilder's method did not reveal reticular fibers in these spaces. Electron microscopy revealed three readily recognizable zones: a juxtacellular zone of a network of replicated basal lamina, and intermediate zone of stellate granules of mucoid material, and a central core of densely packed aperiodic filaments or collagen fibrils. The histogenesis of cystlike spaces and their realtionship with biologic behaviors of the neoplasm were discussed.