Middle ear adenoma with uncommon presentation and literature review.

Middle ear adenoma (MEA) is a rare benign tumour. Here we report a case of MEA in a 39-year-old man with hearing loss. Some significant histopathological features of MEA and neuroendocrine differentiation identified by immunohistochemistry are described. The tumour showed remarkable and rare degenerative histological characteristics. There were a few tumour cells which were covered by degenerated tissue. Consequently, following frozen biopsy, the tumour was misdiagnosed as chronic ear inflammation. No recurrence was seen in this patient after 45 months of follow-up; regular clinical and radiological follow-up is necessary since recurrence is possible. A literature review for MEA is presented and this type of tumour is discussed clinically, microscopically and immunohistochemically. The differential diagnosis and associated treatment are described.