Carotid body tumor
What is a carotid body tumor?
A carotid body tumor (also known as a carotid body paraganglioma or a chemodectoma) is a vascular tumor that begins in the external layer of the carotid artery and extends into the internal and external carotid arteries. About 65 percent of all head and neck paragangliomas are carotid body tumors.
The carotid body, which originates in the neural crest, is important in the body's acute adaptation to fluctuating concentrations of oxygen, carbon dioxide and pH. The carotid body protects the organs from hypoxic damage by releasing neurotransmitters that increase the ventilatory rate when stimulated.
At first a carotid body tumor may not present any symptoms, but it can usually be felt as a slow-growing, painless mass on the side of a person’s neck. As the tumor gets bigger, over the course of several years, it may start to cause symptoms that include:
- Difficulty swallowing
- High blood pressure or heart palpitations
- Partial paralysis or numbness in the tongue
- The distinct whooshing sound of blood pushing past an obstruction
- Vision changes or a drooping eyelid
- Weakness or pain in the shoulders
There are three different types of carotid body tumors:
The most common type is the sporadic form, representing approximately 85 percent of carotid body tumors. The familial type is more common in younger patients. The hyperplastic form is very common in patients with chronic hypoxia and includes those patients living at a high altitude.