Cystadenoma of the parotid gland with unusual prominent lymphoid stroma

A rare variant of the cystadenoma of salivary gland origin is presented, which occurred in the parotid of a 36-year-old, otherwise healthy female patient. The tumour showed a dense follicle-containing lymphoid stroma, resembling papillary cystadenoma lymphomatosum (Warthin's tumour). In contrast to that, the epithelial lining gave a more irregular impression and oncocytic metaplasia were completely absent. Light microscopic and immunohistochemical features of the tumour are described and compared with those of classical cystadenoma and papillary cystadenoma lymphomatosum (Warthin's tumour). Other relevant multicystic epithelial parotid lesions, which are commonly associated with a prominent lymphoid component are discussed.