Acinous cell carcinoma: a histogenetic hypothesis.

A proposed origin of acinous cell carcinoma of the parotid gland from serous cells of the acinar part of the salivary unit has been challenged. To date, the alternative histogenetic concept of origin from the reserve cell of the intercalated duct has been largely conjectural and based on light microscopic and only isolated electron microscopic evidence. Light and electron microscopic findings now support a terminal duct origin for at least some acinous cell carcinomas.