Terminal duct adenocarcinomas of the parotid gland.

The major salivary glands are considered to rarely be the sites of primary terminal duct adenocarcinomas, a neoplasm with a considerable predilection for origin from intraoral minor salivary glands. We present a clinicopathological study of 22 terminal duct adenocarcinomas of the parotid gland, the largest single series to date. A comparison between the parotid neoplasms and over 200 minor salivary gland terminal duct adenocarcinomas indicates there is little difference in biological behaviour and confirms the low-grade quality of the carcinomas, regardless of site of origin.