Overview

About the parathyroid glands

The parathyroid glands are four small glands located in the neck or upper mediastinum (chest) near the thyroid gland. They are part of the endocrine system. The endocrine system regulates the hormones in the body. Like all parts of the endocrine system, the parathyroid glands play an important role in the body. These glands make parathyroid hormone (PTH), which regulates the levels of calcium and phosphorus in the blood.

About parathyroid cancer

Cancer occurs when cells in the body become abnormal and start to multiply without control or order. These cells form a growth of tissue, called a tumor. A tumor can be benign (noncancerous) or malignant (cancerous, meaning it can spread to other parts of the body). A parathyroid tumor usually arises in one of the four parathyroid glands.

A parathyroid tumor, whether it is benign or malignant, can cause significant effects because the amount of calcium in the blood rises, resulting in a serious condition called hypercalcemia.

This section covers tumors found in the parathyroid. Learn more about tumors that begin in the thyroid gland.

Find out more about basic cancer terms used in this section.