Question
A 40-year-old woman is suspected of having a carotid body tumor. Which one of the following is most characteristic of such a tumor?
| A. |
They secrete catecholamines.
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| B. |
They are more common at sea level.
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| C. |
They arise from structures that respond to changes in blood volume.
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| D. |
They arise from the structures that respond to changes in PO2.
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Show Answer
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Correct Answer � D
Explanation
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Answer- D They arise from the structures that respond to changes in PO2.
Carotid body tumor is the most common type of paraganglioma in the head and neck
region, followed by the glomus jugular tumor.
This is a rare tumour that has a higher incidence in areas where people live at high altitudes because of chronic hypoxia leading to carotid body hyperplasia.
Carotid is derived from neural crest which is essential for adaptation in fluctuation in the O2, CO2 and pH.
The tumours are usually benign with only a small number of cases producing proven metastases.
Pathologically, it is well-encapsulated, hard creamy yellowish tumour with dense fibrous tissue. Carotid body tumour cells are not hormonally active.
