LAUSR

Xanthomas are visibly deformed cholesterol deposits that are commonly associated with lipid disorders, such as familial hypercholesterolemia (FH) or rare sitosterolemia. We present the first report of two cases of carotid sheath xanthomas in patients with lipid disorders. Case 1 involved a 26-year-old woman presenting with two heterogeneous mutations on the ABCG5 gene-as noted on genetic testing-who was finally diagnosed with sitosterolemia. Ultrasonography (US) revealed hypoechoic masses centered in the bilateral carotid sheath, which gradually reduced in size after diet control and the use of ezetimibe. Case 2 involved a 27-year-old man who was diagnosed with possible FH and had recurrent bilateral buttock xanthomas, as well as bilateral carotid sheath masses detected by US. Postoperative pathological examination of the resected right neck mass confirmed a xanthoma with proliferation of multinucleated giant cells and deposition of cholesterol clefts.