SECTION EDITOR: EDWARD B. STELOW, MD
Diagnosis: Ceruminous gland adenocarcinoma
The differential diagnosis in this case included adenoid cystic carcinoma, mucoepidermoid carcinoma, and salivary duct carcinoma of the parotid gland. Adenoid cystic carcinoma was rejected based on the morphological appearance of the tumor, the presence of in situ carcinoma associated with the glands of the external ear, and the lack of myoepithelial differentiation in the basal and abluminal tumor cells (negative for smooth muscle actin, calponin, S-100 protein, and glial fibrillary acidic protein). The lack of mucous cells and a negative mucin stain did not support mucoepidermoid carcinoma. Morphologically, the tumor resembled salivary duct carcinoma; however, immunohistochemical stains were negative for hormone receptors (estrogen, progesterone, and androgen receptor) and gross cystic disease fluid protein. Most salivary duct carcinomas are very aggressive tumors of relatively short duration that arise in the parotid gland and are positive for androgen receptor and gross cystic disease fluid protein. Focal in situ carcinoma involving secretory glands of the external ear and cribriform architecture, abundant eosinophilic cytoplasm in tumor cells, and focal apoptotic secretions favored a ceruminous gland adenocarcinoma.
Pathology Quiz Case 1: Diagnosis. Arch Otolaryngol Head Neck Surg. 2012;138(9):872. doi:10.1001/archotol.138.9.872