Lenvatinib Administration for Anaplastic Thyroid Carcinoma with Brain Metastasis.

We describe the use of the tyrosine kinase inhibitor lenvatinib in a patient with brain tumor metastases from anaplastic thyroid carcinoma (ATC). A 52-year-old Japanese male presented with consciousness loss. Imaging revealed a thyroid tumor and multiple brain lesions. After the brain tumor's resection, pathology results provided the diagnosis of ATC. Total thyroidectomy was performed, followed by whole-brain irradiation. Additional brain lesions later developed, and lenvatinib therapy was initiated with no remarkable complications. However, the treatment effects were limited, and the patient died 2 months after starting lenvatinib, 202 days after the initial brain surgery. Relevant literature is discussed.