Unusual metastasis of poorly differentiated thyroid carcinoma to the masticator space.

We report an unusual case of metastasis to the masticator space from a poorly differentiated carcinoma of the thyroid. A 34-year-old woman presented with a swelling in the left parotid region of 4 to 5 months' duration, which was progressively increasing in size. A CT scan of the head and neck revealed a heterogeneous, hypervascular mass in the left masticator space. Metastatic disease to the masticator space and to the jaws is a rare event.