Abstract

Anaplastic thyroid cancer is an uncommon malignant tumor, usually fatal, primarily affecting older adults and doesn’t have effective systemic therapy. The median survival is less than 6 months from diagnosis. Brain metastases are low frequency and reach 18%. We present the case of a patient with papillary carcinoma of the thyroid who takes an aggressive form, becoming anaplastic carcinoma, with involvement of the central nervous system (CNS) manifested by paralysis of the cranial nerve IV, which is rare clinical condition