Middle Ear Adenomatous Neuroendocrine Tumours: Single Institution Experience With Five Cases

Middle ear adenomatous neuroendocrine tumours are extremely rare causes of middle ear masses. Differential diagnosis is of primary importance to decide on the correct management since they require surgery whereas other lesions can be actively watched. CT and MRI show a non-hypervascular lesion, differentiating it from paraganglioma. It is a mesotympanic lesion that usually encases the ossicles without bone erosion and it can invade the retrotympanum and Eustachian tube. Radical surgery is the treatment of choice. Since middle ear adenomatous neuroendocrine tumours adhere to adjacent structures and lack a tumour capsule, gross total resection is challenging. Late recurrences may be observed and complicated by the development of middle ear cholesteatoma, emphasising the importance of a long follow-up. Recurrence can be associated with neural and intracranial invasion, lymph node or distant metastasis, highlighting the malignant potential of middle ear adenomatous neuroendocrine tumours.