Parathyroid cancer is a very rare cancer that develops in the parathyroid glands. A pair of these pea-sized glands sits next to the thyroid on either side of the front of the neck.
The four parathyroid glands produce parathyroid hormone (PTH). This chemical
raises calcium levels in the blood by forcing the bones to release calcium
stimulates the intestines to absorb more calcium from food
signals the kidneys to withhold calcium from the urine.
Healthy parathyroid glands adjust their production of PTH to keep blood calcium levels within a normal range.
When parathyroid cells become cancerous, they multiply out of control. They usually form a firm, grayish-white tumor. The tumor can invade the thyroid gland and neck muscles.
As the cancerous cells grow, they usually produce too much PTH. This causes abnormally high levels of calcium in the blood (hypercalcemia). PTH can get so high that the bones pour out too much calcium. This can cause bone pain and lead to osteoporosis (thin, brittle bones).
Elevated levels of PTH also force the kidneys to retain large amounts of calcium, triggering the formation of kidney stones. Very high calcium can also cause kidney damage, dehydration, and confusion.
Parathyroid cancer usually occurs in adults in their 50s and 60s. Because it is so rare, researchers have not determined whether specific environmental or lifestyle factors increase the risk of this cancer. Some cases seem to have a genetic link, with several generations of a single family affected.