Evaluation of rare choroid plexus metastasis from papillary thyroid carcinoma with multimodality imaging.

Papillary thyroid carcinoma (PTC) is the most common malignancy of thyroid gland. Though it metastasizes primarily through lymphatics, hematogenous spread is not infrequent. We report the case of a 62-year-old male patient with intraventricular choroid plexus metastasis from PTC, incidentally detected on post-high-dose radioiodine therapy whole-body I scan, which is an extremely rare presentation. Only 3 cases of choroid plexus metastasis from thyroid carcinoma have been reported. Further multimodality radiological investigations confirmed diagnosis and helped in assessing treatment response. The patient received gamma-knife stereotactic radiosurgery, and follow-up radiological imaging suggested improvement of intracranial metastasis.