The appearance of this tumor under the
microscope is unique. There are cystic spaces surrounded by two uniform rows of
oncocytes, which are
epithelial cells with abundant, granular, eosinophilic cytoplasm. The cystic spaces have epithelium referred to as papillary infoldings that protrude into them. Additionally, the epithelium has lymphoid stroma with
germinal center formation. The
differential diagnosis includes
sebaceous lymphadenoma and
oncocytoma. Image:Warthin's tumor.jpg|This Warthin's tumor presented as a parotid mass in a middle-aged male, who underwent superficial parotidectomy. The tumor, at the right of the image, is well-demarcated from the adjacent parotid tissue and tends to shell out from it. Image:Papillary cystadenoma lymphomatosum1.jpg|Low magnification
micrograph of a Warthin tumor arising from the parotid gland. Image:Warthin tumor (1).jpg|Histopathology of Warthin tumor in the parotid gland. H&E stain. Image:Warthin tumor (2).jpg|Histopathology of Warthin tumor in the parotid gland. Another view of a file "Warthin tumor (1).jpg". H&E stain. Image:Warthin tumor (3).jpg|Histopathology of Warthin tumor in the parotid gland. Higher magnification of a file "Warthin tumor (1).jpg". H&E stain. Image:Papillary cystadenoma lymphomatosum2.jpg|Intermediate magnification
micrograph of a Warthin tumor. Image:Papillary cystadenoma lymphomatosum3.jpg|High magnification
micrograph of a Warthin tumor showing the characteristic bilayered epithelium. ==Treatment==