Imaging findings of thyroidal sarcoma.

From 1997 to 2013, 8849 patients with several disorders of the thyroid were treated in our surgical department. In nine patients (0.1%), primary thyroid sarcoma (PTS) was diagnosed. In eight patients, PTS manifested as a thyroid mass (range, 25-90 mm). In one case, a global enlargement of the thyroid was seen. Clinically, all patients presented with neck swelling. On ultrasound, PTS was predominantly hypoechoic. On computed tomography, the sarcomas were hypodense. On magnetic resonance imaging, PTS had inhomogeneous signal increase on T2-weighted images and signal decrease on T1-weighted images with inhomogeneous enhancement.