[Middle ear adenoma]

Middle ear neoplasms are rare lesions and difficult to diagnose due to limited information about their biology and the lack of standard criteria for their analysis. Herein, a middle ear neoplasm is described that became apparent because of its appearance in the external ear duct as it protruded from the middle ear through the eardrum. Following resection, the specimen was determined to be a benign epithelial tumor. Absence of adequate clinical information complicated the diagnosis; therefore,histochemistry and immunohistochemistry analyses were necessary to reach the final diagnosis of middle ear adenoma. Diagnostic criteria are proposed to properly diagnose these types of lesions.