Warthin-Like Tumor of the Esophagus

Abstract

Warthin's tumor is the second most common benign neoplasm that occurs within the parotid gland, comprising approximately 14 % of all parotid tumors. Clinically, features are lacking and patients are typically asymptomatic. The occurrence of extra-parotid involvement, particularly within the esophagus has not been previously reported. 72-year old male smoker with previous history of H-pylori gastritis, arteriovenous malformation of the jejunum, and colonic polyps presented to his gastroenterologist for evaluation of melena for two weeks duration. Review of systems was negative and physical exam was benign. Laboratory examination showed normocytic anemia. Patient underwent an upper endoscopy which revealed a nodule within the distal third of the esophagus. Endoscopic ultrasound confirmed the presence of an 14 mm nodule embedded within the muscularis mucosa of the esophagus. The nodule was successfully excised via endoscopic mucosal resection. Immunohistochemical stains of the specimen was positive for CK7 and negative for both CK20 and smooth muscle myosin heavy chain. Cytopathology reported a submucosal oncocytic papillary cystadenoma with a lymphoid stroma, consistent with a Warthin's tumor. The patient underwent endoscopic surveillance one month following the excision with no evidence of recurrence. Warthin's tumor most commonly occur in male smokers around the sixth or seventh decade of life. The pathogenesis of this tumor is highly controversial, but it is believed to arise from malignant transformation of ductal cells within the parotid gland secondary to a toxic exposure. These tumors rarely undergo malignant transformation; however, some have been associated with lymphoproliferative diseases due to the involvement of a reactive lymphoid stroma. Histocytological features of a well-encapsulated cystic mass with a lymphoid stroma surrounded by an oncocytic epithelium with papillary projections is required to make the diagnosis. Our patient's nodule histologically appeared as Warthin's tumor. Whether the same prognostic features can be applied remains to be determined.1836_A Figure 1. This 1.4 cm esophageal sub-mucosal tumor is composed of cystic neoplastic glands (T), lined by a double layer of epithelial cells which exhibit a combined oncocytic and papillary histology with surrounding lymphocytic (L) stroma. These features strikingly differentiate the tumor glands from the normal esophageal mucus glands (black arrow).1836_B Figure 2. The mucus secreting acini (a) of the normal esophageal mucous glands (black arrow) are lined by inconspicuous flattened outer myoepithelial cells and large mucus filled inner cuboidal epithelial cells. The cystic tumor (T) glands are lined by an outer cuboidal basal cell and a larger rounded cells with voluminous finely granular pink cytoplasm (oncocytes).1836_C Figure 3. Endoscopic view of the esophageal mass.