Risks for parathyroid cancer

Certain behaviours, substances or conditions can affect your risk, or chance, of developing cancer. Some things increase your risk and some things decrease it. Most cancers are the result of many risks. But sometimes cancer develops in people who don't have any risks.

Parathyroid cancer is very rare. Most people diagnosed with this cancer are middle aged. It affects men and women equally.

Some people with certain genetic conditions have a higher than average risk for parathyroid cancer. Talk to your doctor about your risk. If you have a genetic condition that increases the risk of parathyroid cancer, you may need to visit your doctor more often to check for parathyroid cancer. Your doctor will recommend what tests you should have and how often you should have them.

The following can increase your risk for parathyroid cancer. None of these risks can be changed. Until we learn more about other risks, there are no specific ways you can lower your risk for parathyroid cancer.

Hyperparathyroidism–jaw tumour (HPT-JT) syndrome

Familial isolated hyperparathyroidism (FIHP)

Multiple endocrine neoplasia type 1 (MEN1)

Hyperparathyroidism–jaw tumour (HPT-JT) syndrome

Familial isolated hyperparathyroidism (FIHP)

Multiple endocrine neoplasia type 1 (MEN1)

There is convincing evidence that the following factors increase your risk for parathyroid cancer.

Hyperparathyroidism–jaw tumour (HPT-JT) syndrome is an inherited condition usually caused by a change (mutation) in the CDC73 gene. HPT-JT syndrome causes non-cancerous tumours (called adenomas) to grow in one or more of the parathyroid glands.

These tumours cause the parathyroid glands to become overactive and make too much parathyroid hormone (called hyperparathyroidism). Up to about one-third of people with HPT-JT syndrome develop parathyroid cancer. People with HPT-JT syndrome may also develop non-cancerous tumours (called fibromas) in their jaw bones.

Familial isolated hyperparathyroidism (FIHP) is an inherited condition that causes one or more of the parathyroid glands to become overactive. It can be caused by changes in the MEN1, CASR, CGM2 or CDC73 genes. FIHP is usually diagnosed when there are no symptoms or features of other similar conditions, such as HPT-JT and MEN1. Most people with FIHP have non-cancerous parathyroid tumours that cause the glands to be overactive. In rare cases, people with FIHP develop parathyroid cancer.

Multiple endocrine neoplasia type 1 (MEN1) is an inherited condition caused by changes in the MEN1 gene. MEN1 causes tumours in the endocrine glands, most often in the parathyroid glands, pancreas and pituitary gland. The tumours are usually non-cancerous. Most people with MEN1 have non-cancerous parathyroid tumours that cause the glands to be overactive. In very rare cases, people with MEN1 develop parathyroid cancer.

The following have been linked with parathyroid cancer, but there is not enough evidence to show for sure that they are risks. More research is needed.

• certain gene mutations
• secondary hyperparathyroidism – occurs when a condition outside the parathyroid glands (most often long-term kidney disease) causes the parathyroid glands to be overactive
• multiple endocrine neoplasia type 2A (MEN2A) – an inherited condition caused by changes in the RET gene that causes tumours in the endocrine glands
• radiation therapy to the neck

To make the decisions that are right for you, ask your doctor questions about risks. Learn how cancer can be prevented and what you can do to reduce your risk.