Objective: Metastases to the choroid plexus from extracranial tumors are rare. Kidney, lung, and colon are the common primary origins of choroid plexus metastases. Choroid plexus metastases from thyroid carcinoma are very rare, with only 2 cases reported thus far. We report the third case of choroid plexus metastasis from thyroid carcinoma.
Clinical presentation: A 75-year-old man presented with severe headache, nausea, and vomiting. He had a history of thyroid carcinoma, which had metastasized to the lymph nodes and lung. Computed tomography, magnetic resonance imaging, and magnetic resonance angiography revealed right intraventricular hemorrhage with mild hydrocephalus, without evidence of a bleeding source. The bleeding source was assumed to be the choroid plexus metastasis in the trigone of the right lateral ventricle (following second admission).
Intervention: Surgery was performed using a navigation-assisted system. The tumor was entirely removed, including some choroid plexus tissue. A ventriculoperitoneal shunt was also performed to treat the hydrocephalus. Histopathological examination revealed brain metastasis from papillary thyroid carcinoma. Postoperatively, the patient showed good recovery, with nausea and vomiting improved, and gait disturbance diminished. The patient was discharged from the hospital one month later.
Conclusion: Choroid plexus metastasis from papillary thyroid carcinoma is very rare, and this is the first case of intraventricular hemorrhage reported.