Middle Ear Neuroendocrine Adenoma: A Case Report and Literature Review

Abstract

Neuroendocrine adenomas of the middle ear are rare tumors that represent less than 2% of primary tumors of the ear. In this paper, we describe a case of a 40-year-old woman who developed neuroendocrine adenoma of the middle ear. The specific management strategy for this rare tumor is unclear; information in the available literature on the management of this tumor is varied. However, an extensive demolition seems to be the gold standard treatment for this tumor to avoid recurrence and regional metastases in the lymph node or distant metastases. For the present case, we performed an incisional biopsy to confirm the diagnosis, and thereafter, we performed a canal-wall-down tympanoplasty. For cases like the present one, careful long-term clinical and instrumental follow-up is required to monitor progress and facilitate patient recovery.

Figure 1

Audiometric threshold before (a) and after (b) the surgical treatment. Red circles and lines: right ear air threshold, red triangles and lines: masked right ear air threshold, red triangles: right ear bone threshold, and blue crosses and lines: left ear air threshold.

Figure 2

Axial magnetic resonance imaging (MRI) scans of the middle ear. (a) T1 fat-saturated MRI revealed tissue in the middle ear. (b) T1 diffusion-weighted imaging did not show a restriction of diffusion in the tissue, as is typical of cholesteatoma.

Figure 3

Neuroendocrine adenoma of the middle ear (encircled) during the first surgery; view from the ear canal.

Figure 4

(a) Hematoxylin and eosin stain; the tumor was unencapsulated with an organoid growth pattern characterized by rounded nests and trabecular and glandular aggregates, with hyalinized fibrous stroma in the background (magnification ×25). Cytologically, the tumor cells lacked nuclear pleomorphism and exhibited finely dispersed nuclear chromatin (magnification ×100). (b) Immunohistochemistry results showed diffuse positivity for Cam 5.2.

Figure 5

(a) Axial T1 fat-saturated magnetic resonance imaging scan of the middle ear; blue arrow indicated the residual tumor in the middle ear before the canal-wall-down tympanoplasty. (b) Axial T1 fat-saturated magnetic resonance imaging scan of the middle ear after one year from the surgical procedure; the blue rectangle showed the absence of recurrence or persistence of the disease.