Ectopic cervical thymoma is an extremely rare tumor thought to arise from ectopic thymic tissue caused by the aberrant migration of the embryonic thymus. We present the case of a 44-year-old woman with an ectopic cervical thymoma located in the carotid triangle. A computed tomography (CT) scan detected a mass in her right carotid triangle. On an unenhanced scan, the tumor showed homogeneous isodensity compared with muscles, and neither fat nor calcification was detected. A contrast-enhanced CT image obtained during the arterial phase showed intratumoral septa, while an image obtained during the parenchymal phase showed cystic changes within the mass. The patient underwent a surgical resection. A histological study enabled a diagnosis of type AB thymoma in which foci with the features of type A thymoma are admixed with foci rich in lymphocytes. This subtype is a benign tumor with a good prognosis. Ectopic cervical thymoma should be included in the differential diagnosis of solid masses located in the carotid triangle when the CT findings are typical of a thymoma.
ASJC Scopus subject areas
- Radiology Nuclear Medicine and imaging