Abstract
Jugular vein aneurysms are extremely rare, and cases concurrent with papillary thyroid carcinoma (PTC) and multi-site venous aneurysms are even rarer. This report describes a 59-year-old female with left internal jugular vein aneurysm and left superficial femoral vein aneurysm complicated by thrombosis after total thyroidectomy for PTC. The thrombus within the internal jugular vein was similar to a metastatic lymph node; however, a correct diagnosis was ultimately reached under the physician's examination. We present this case to enhance junior physicians' skills in the differential diagnosis of neck masses and propose a preliminary hypothesis regarding the etiology of venous aneurysms.