Parathyroid cancer is a rare disease in which malignant (cancer) cells form in the tissues of a parathyroid gland.
The parathyroid glands are four pea-sized organs found in the neck near the thyroid gland. The parathyroid glands make parathyroid hormone (PTH or parathormone). PTH helps the body use and store calcium to keep the calcium in the blood at normal levels.
Anatomy of the thyroid and parathyroid glands. The thyroid gland lies at the base of the throat near the trachea. It is shaped like a butterfly, with the right lobe and left lobe connected by a thin piece of tissue called the isthmus. The parathyroid glands are four pea-sized organs found in the neck near the thyroid. The thyroid and parathyroid glands make hormones.
A parathyroid gland may become overactive and make too much PTH, a condition called hyperparathyroidism. Hyperparathyroidism can occur when a benign tumor (noncancer), called an adenoma, forms on one of the parathyroid glands, and causes it to grow and become overactive. Sometimes hyperparathyroidism can be caused by parathyroid cancer, but this is very rare.
The extra PTH causes:
- The calcium stored in the bones to move into the blood.
- The intestines to absorb more calcium from the food we eat.
This condition is called hypercalcemia (too much calcium in the blood).
The hypercalcemia caused by hyperparathyroidism is more serious and life-threatening than parathyroid cancer itself and treating hypercalcemia is as important as treating the cancer.
Having certain inherited disorders can increase the risk of developing parathyroid cancer.
Anything that increases the chance of getting a disease is called a risk factor. Risk factors for parathyroid cancer include the following rare disorders that are inherited (passed down from parent to child):
- Familial isolated hyperparathyroidism (FIHP).
- Multiple endocrine neoplasia type 1 (MEN1) syndrome.
Treatment with radiation therapy may increase the risk of developing a parathyroid adenoma.
Signs and symptoms of parathyroid cancer include weakness, feeling tired, and a lump in the neck.
Most parathyroid cancer signs and symptoms are caused by the hypercalcemia that develops. Signs and symptoms of hypercalcemia include the following: