Carotid Body Tumour

Axial and sagittal CT of the neck show an enhancing mass arising in the carotid space, between the internal and external carotid arteries. There is a tongue of tissue extending medially and causing mild asymmetry of the oropharynx. The findings are typical of carotid body tumour (paraganglioma).
Carotid body tumours arise from neuroectodermal cells associated with the carotid body. They are highly vasular lesions. Carotid body tumours may extend locally to cranial nerves, pharynx, skull base or intracranially. Growth rate is typically slow, averaging 5mm/year. They show malignant transformation in 6%, with metastases to local nodes, brachial plexus, brain, lung, bone and elsewhere.
Reference: Dahnert W. Radiology Review Manual. 5th edition. Lippincott, Williams & Wilkins 2003.
Credit: Dr Jeanette Taylor
Credit: Dr Laughlin Dawes
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