Brain metastases from medullary thyroid carcinoma in a patient with multiple endocrine neoplasia type 2A.

Medullary thyroid carcinoma (MTC) is an uncommon thyroid cancer occurring in less than 10% of patients with thyroid cancer. Brain metastasis from MTC is exceedingly rare. Only six cases of brain metastasis from MTC have been reported in the literature and none had MTC as a part of multiple endocrine neoplasia (MEN) syndrome. We report a 42-year-old Caucasian male with MEN 2A who presented with neurological symptoms 25 years after total thyroidectomy with lymphadenectomy for MTC metastatic to local lymph nodes. A brain magnetic resonance imaging (MRI) showed a 4-cm cystic mass and a 1-cm nodule in the left frontal-parietal lobe in addition to a 0.8-cm cystic mass in the left frontal lobe and multiple tiny cerebellar metastatic lesions. Partial resection of the cerebral metastasis followed by whole brain radiotherapy resulted in resolution of the neurological symptoms. However, the patient had multiple systemic metastasis from the MTC and he died of systemic complications due to metastatic MTC. To our knowledge this is the first report of brain metastases from MTC in a patient with MEN 2A.