Middle ear adenoma with neuroendocrine differentiation

The lining of the middle ear cleft is normally a thin modified respiratory type mucosa. Normal mucosa of the middle ear is devoid of salivary type seromucous glands. Middle ear adenoma is a rare tumor that seems to be derived from the middle ear mucosa. This tumor has been previously described under a variety of names because of its different nature and biological behavior. We herein report a case of middle ear tumor that shows adenomatous and neuroendocrine features. A 64-year-old woman presented with a history of hearing loss, tinnitus and stuffy feeling of the right ear. The patient was treated two times for ear polyp. She finally underwent a tympanomastoidectomy and there was no evidence of recurrence 18 months after the procedure. Histopathological examination displayed cuboidal and columnar cells, arranged as glands, trabeculae and solid sheets. Neuroendocrine differentiation was revealed by immunohistochemical staining with polyclonal antibodies against neuron specific enolase and chromogranin antigens.