Warthin tumor (also known as cystadenolymphoma), is a benign and frequent salivary gland neoplasm.~It represents about 2% to 15% of all primary epithelial tumors of the parotid gland.~Warthin tumor is histologically characterized by a dense lymphoid stroma and a double layer of oncocytic epithelium with a papillary and cystic architectural pattern.~Its etiology: remains controversial. Incidence: It is the second most frequent benign neoplasm of the salivary glands after pleomorphic adenoma. Pathophysiology: Initially, Hildebrand proposed that the lesion may be remnants of the branchial pouches and a variant of the lateral cervical cyst. Later, Albrech and Artz proposed the heterotropic origin of Warthin tumor from the neoplastic proliferation of salivary gland ducts present within intra- or para-parotid nodes. Histopathology: Grossly, Warthin tumor is a well-circumscribed spherical to oval mass. On cut section, there are solid areas and multiple cysts with papillary projections.~Cytology: Smears characteristically show oncocytic epithelial cells without atypia admixed with polymorphous lymphocytes and cellular debris.~Microscopic Findings: Warthin tumors are composed of varying proportions of papillary- cystic structures lined by oncocytic epithelial cells and a lymphoid stroma with germinal centers.~Clinically, Warthin tumor presents as a rounded or an ovoid nodular painless, slow-growing, fluctuant to firm at palpation. It can be unilateral, bilateral, or multicentric and is asymptomatic in 90% of cases.~Prognosis: Warthin's tumor has a favorable prognosis and almost never recurs. Malignant degeneration of Warthin tumor is very rare.~Complications:~Local Recurrence; The local recurrence rate is low; when recurrence does occur, it is probably due to multifocal tumors or inadequate excision.~Malignant Transformation; Malignant transformation in a Warthin tumor is extremely rare. The most frequent histological types of malignant transformation in a Warthin tumor are mucoepidermoid carcinoma, squamous cell carcinoma, undifferentiated carcinoma, oncocytic adenocarcinoma, and adenocarcinoma.
Comparison between Ultrasound-Guided Ethanol Sclerotherapy (UGES) & surgical excision in management of warthin tumor of parotid gland.