Primary Neuroendocrine Carcinoma of the Cerebellopontine Angle: A Case Report and Literature Review.

Primary intracranial neuroendocrine tumors are extremely rare malignancies with very few cases reported in the world literature. We describe a primary neuroendocrine carcinoma arising from the right cerebellopontine angle, the second case that has been described in this location. The possible origin in this place and treatment are described. A 29-year-old male patient, diagnosed with schwannoma of the right cerebellopontine angle, and treated with radiosurgery at another institution, came to our hospital six months later, The patient presented with a history of rapid progression of numbness on the right side of the face, diplopia, dizziness, vomiting, and facial palsy. On examination, the right cranial nerves V, VI, VII, VIII, and IX were affected. The MRI showed tumor growth occupying the right cerebellopontine angle, with compression of the brain stem and cerebellum. A right retromastoid craniectomy removed the tumor partially and the histopathological examination revealed a high-grade neuroendocrine carcinoma. We describe a primary neuroendocrine tumor of the brain that, despite its rarity, must be considered in the differential diagnosis. There are currently no guidelines for the management of these tumors. According to previously reported cases, surgery is the first line of treatment, followed by radiotherapy or chemotherapy. We consider that such a rare case is needed to be reported for a better understanding of the disease and its neurobiology.