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Parathyroid cancer

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What is parathyroid cancer?

Parathyroid cancer is a malignant tumour that starts in cells of a parathyroid gland. Malignant means that it can spread, or metastasize, to other parts of the body.

The parathyroid glands are part of the endocrine system. This system is the group of glands and cells in the body that make and release hormones. Most people have 4 parathyroid glands. There are 2 on each side of the thyroid, which is in the neck. The parathyroid glands are usually found on the back surface of the thyroid, but sometimes they are inside the thyroid. Some people may have more parathyroid glands in other parts of the neck or in the chest. The parathyroid glands make parathyroid hormone (PTH or parathormone), which controls the level of calcium in your blood.

Cells in a parathyroid gland sometimes change and no longer grow or behave normally. These changes may lead to non-cancerous, or benign, conditions such as parathyroid hyperplasia. They can also lead to non-cancerous tumours such as parathyroid adenoma.

In some cases, changes to cells in a parathyroid gland can cause cancer. This type of cancer is called parathyroid carcinoma. It is a rare, slow-growing tumour.

Most parathyroid adenomas and parathyroid carcinomas are functional. This means that they make PTH. A high level of PTH is called hyperparathyroidism. It can lead to high levels of calcium in the blood, or hypercalcemia.

Parathyroid adenomas and parathyroid carcinomas are a type of neuroendocrine tumour, which are tumours that start in the neuroendocrine system.

Diagram of location of parathyroid glands


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