Clinical, histological and immunohistochemical features of ceruminous adenoma

Ceruminous gland tumors are infrequent lesions of the external auditory canal (EAC). Controversy exists regarding several aspects of these tumors. In this report we presented a case of 63 years old woman with an 8-year history of a painless mass in the left EAC. Physical examination showed a skin-covered mass, occupying all its lumen. First superficial biopsy led to an initial erroneous diagnosis of papilloma. Local wide resection of the lesion was performed one month later. Histological examination revealed a lesion composed of solid nests and papillomatous and cystic glands surrounded by a hyaline sheath. Immunohistochemically, two different cell layers were demonstrated: a luminal epithelial cell layer with positive staining with cytokeratin 7 (CK7) and an outer myoepithelial cell layer, with positive staining with actin and S-100 protein. The proliferative index (Ki-67) was very low. The diagnosis was ceruminous gland adenoma. Two years after the operation, the patient is in good health and with normal ultrasound and laboratory results. We believe that conservative surgery seems to be ideal treatment in case of ceruminous adenoma.