A Rare Presentation of Primary Cutaneous Low-Grade Neuroendocrine Tumor of the External Auditory Canal

Abstract

Objective: To describe the first case of a primary cutaneous low-grade neuroendocrine tumor (cLGNET) originating from the external auditory canal as well as our team's surgical management. Patient: A healthy 34-year-old female presented with a lowgrade neuroendocrine tumor of her right external auditory canal (EAC) which extended from the posterior-superior aspect of the EAC into the middle ear. Intervention: A complete otological examination was performed in addition to CT and MRI imaging. The low-grade neuroendocrine tumor was surgically biopsied and further surgery was recommended for complete resection. Results: Audiogram revealed profound right sensorineural hearing loss. CT scan demonstrated complete opacification of the right EAC, middle ear, and mastoid air cells, dystrophic calcification in the mesotympanum overlying the cochlear promontory, and no associated osseous erosion. MRI revealed abnormal FLAIR hyperintensity and enhancement of the labyrinthine segment of the right facial nerve, cochlea, and horizontal and posterior semicircular canals. An enhancing mass opacifying the right EAC demonstrating restricted diffusion on diffusion-weighted image was also evident. Pathologic examination and immunohistochemical staining confirmed a diagnosis of primary cLGNET of the EAC. Conclusion: Primary cLGNETs of the external ear are exceedingly rare but should be considered if an adult patient presents with a mass in the EAC. Management should include early biopsy and surgical excision followed by histological and immunohistochemical confirmation.

68Ga-DOTATATE Uptake in Well-Differentiated Neuroendocrine Tumor of the External Auditory Canal

“…3 Well-differentiated primary neuroendocrine tumors with external auditory canal location are extremely rare. [4][5][6][7] Surgical excision and additional radiation therapy have been reported as the preferred methods in disease management in the current literature. 4,5,8…”

“…On the other hand, 18 F-FDG PET/CT can be performed for predicting prognosis of neuroendocrine neoplasms, and it can help to select treatment modality 3. Well-differentiated primary neuroendocrine tumors with external auditory canal location are extremely rare [4][5][6][7]. Surgical excision and additional radiation therapy have been reported as the preferred methods in disease management in the current literature 4,5,8.…”

“…[4][5][6][7] Surgical excision and additional radiation therapy have been reported as the preferred methods in disease management in the current literature. 4,5,8…”