Middle ear adenomatous neuroendocrine tumors: a 25-year experience at MD Anderson Cancer Center.

Neuroendocrine tumors are extremely rare in the middle ear. We reviewed our institutional experience with middle ear adenomatous neuroendocrine tumors (MEANTs). We searched our institution's pathology files to identify patients treated from 1990 to 2015 who had lesions classified as middle ear adenomas, adenomatous tumors, adenomatous tumors with neuroendocrine differentiation, carcinoid tumors of the middle ear, low-grade neuroendocrine tumors of the middle ear, and neuroendocrine carcinomas of the middle ear and identified 14 such patients for whom follow-up information was available. Herein, we review the pathology and differential diagnosis of these patients' tumors and discuss the management and follow-up of these patients. Our report adds to the series cases of MEANTs with recurrences, lymph node involvement, distant metastases, and tumor-related deaths. Our experience suggests that, although these tumors have long been considered to be low-aggression neoplasms, long-term follow-up studies to ascertain this supposed benignity are warranted.