Which option correctly states the vessels between which a carotid body tumor typically lies?

• A. Between the external carotid artery and the vertebral artery
• B. Between the internal carotid artery and the external carotid artery
• C. Within the lumen of the common carotid artery
• D. Within the posterior communicating artery

Answer: (B)

Carotid body tumors arise right at the split of the common carotid into the internal and external carotid arteries. They grow in the tissues at that bifurcation, so the mass sits between the two arteries as they diverge. That’s why the description “between the internal carotid artery and the external carotid artery” is the correct way to state its location. It wouldn’t be described as between the external carotid and vertebral arteries, since the vertebral artery is a different vessel higher up and posterior in the neck. It isn’t inside the lumen of the common carotid, because this tumor is extra-luminal at the bifurcation. And it isn’t within the posterior communicating artery, which is an intracranial vessel not at the carotid bifurcation.