Parathyroid disease is a group of conditions involving the parathyroid glands. There are both benign (not cancerous) and malignant (cancerous) types of parathyroid disease.
The parathyroid glands make parathyroid hormone (PTH), which controls the levels of calcium and phosphorous in the blood.
PTH helps maintain bone health, reduces the risk of kidney stones and preserves kidney function.
Parathyroid gland anatomy
There are four parathyroid glands, all located in the neck near the thyroid. Each gland is typically about the size of a kernel of corn.
Usually, one parathyroid gland is located near each corner of the thyroid. Some people are missing a parathyroid gland or have an extra one. Others have parathyroid glands in unusual locations in the neck or chest, but these glands can still work normally.
Parathyroid disease types
Parathyroid disease occurs when a parathyroid gland makes too much or too little PTH, or when a parathyroid cell mutates and becomes cancerous. The types of parathyroid disease are:
Hyperparathyroidism
Hyperparathyroidism means the parathyroid glands are making too much PTH. In most cases, it is caused by an adenoma, which is a benign tumor, on one gland. This causes the gland to produce too much PTH. In about 20% of patients, all four glands are enlarged and producing too much PTH. Too much PTH may cause elevated levels of calcium in the blood, which is called hypercalcemia. This can result in serious problems, including osteoporosis (weakening of the bones) and kidney stones.
Parathyroid cancer
Cancer of the parathyroid glands is extremely rare. Sometimes, parathyroid cancer causes hyperparathyroidism. However, less than 1% of people with hyperparathyroidism have parathyroid cancer. Men and women have the same risk for parathyroid cancer, which usually strikes people in their 50s.
Although parathyroid cancer progresses slowly, it often comes back after treatment. The cancer returns at the original site in in the neck. The average time before return is about two and a half years.
Hypoparathyroidism
Hypoparathyroidism means the body does not make enough PTH and the calcium level in the blood is too low. This is rare and most commonly occurs after surgery for another condition, such as thyroid surgery.
Parathyroid disease risk factors
A risk factor is anything that increases your chances of developing a particular disease. The risk factors for parathyroid disease include:
- Age and gender: Women over age 50 are at an increased risk of developing hyperparathyroidism.
- Having certain inherited disorders can increase your risk of developing parathyroid cancer. These include familial isolated hyperparathyroidism (FIHP) and multiple endocrine neoplasia.
Some cases of parathyroid disease can be passed down from one generation to the next. Genetic counseling may be right for you. Learn more about the risk to you and your family on our genetic testing page.
Learn more about parathyroid disease:
The parathyroid gland is made up of four small glands behind the thyroid gland. Usually, one parathyroid gland is located near each corner of the thyroid. (Click to enlarge.)
Why choose MD Anderson for parathyroid disease treatment?
MD Anderson's Endocrine Center brings together some of the nation's top authorities to treat and diagnose benign (not cancerous) and malignant (cancerous) parathyroid disease.
Parathyroid disease is a rare condition. Our program is one of the few in the nation that specializes in all forms of parathyroid disease. This means we have a level of experience and expertise that help improve your outlook for successful treatment.
Your care is customized by a team of experts from many disciplines, including surgery, medical endocrinology, medical oncology and pathology, as well as a specially trained support staff. They communicate and collaborate closely with each other and with you to ensure the most effective, coordinated care.
We also are constantly researching new and better ways to fight parathyroid disease. This allows us to offer clinical trials of new treatments that might not be available elsewhere.
And at MD Anderson you'll also be surrounded by the strength of one of the nation's largest and most experienced cancer centers. From support groups to counseling to integrative medicine care, we have all the services needed to treat not just the disease, but the whole person.
Until recently, decades passed with little progress in improving the survival rates of parathyroid cancer patients. But our specialized, multidisciplinary team led by Naifa L. Busaidy, M.D., and Nancy D. Perrier, M.D., is bringing parathyroid cancer patients new hope.
We sat down with them to understand this rare disease and how MD Anderson is advancing parathyroid cancer treatment. Here’s what they shared.
What is a parathyroid?
We all have four parathyroids located in our necks. These endocrine glands are only the size of a sunflower seed, but they control the body’s calcium by producing a regulatory hormone.
When a parathyroid becomes overactive and produces too much of this hormone, it’s called hyperparathyroidism. The most common endocrine disorder, hyperparathyroidism can result in tumor growth in the neck. Most parathyroid tumors are benign, but some patients have a genetic mutation that leads to the development of parathyroid cancer.
If hyperparathyroidism progresses to cancer, it’s important that it’s caught and treated early, when treatment is most effective. That’s why it’s so important for patients with hyperparathyroidism to be monitored by skilled specialists, such as by our team.
What are common parathyroid cancer symptoms?
When monitoring hyperparathyroidism, we’re suspicious that it’s progressed to cancer if the patient’s calcium and parathyroid hormone levels are high. We’re also concerned if diagnostic imaging, such as a CT scan, ultrasound or a specialized sestamibi parathyroid scan, shows unusual features of the parathyroid gland, such as the glands appearing bigger than normal or calcified. In this case, we also check for a lump on the patient’s neck. In addition, we closely monitor patients who have a family history of kidney tumors or jaw tumors since they can be at higher risk, as well as carriers of the MEN1, CDC73 and P53 gene mutations.
Patients may notice bodily changes, such as excessive urination, excessive thirst, fatigue and bone pain. If you experience these symptoms, seek care from an experienced team to ensure an accurate diagnosis.
Why is an accurate diagnosis so important for parathyroid cancer patients?
A correct diagnosis is necessary to develop an effective treatment plan.
Because parathyroid cancer is so rare, pathologists are often unfamiliar with the disease when making a diagnosis. Your care team should be able to make a diagnosis by evaluating your diagnostic imaging, calcium levels and parathyroid hormone levels.
If you don’t feel comfortable with the choices laid out by your care team or feel they don’t have enough experience treating parathyroid cancer, get a second opinion. It may save your life.
Why is parathyroid cancer difficult to treat?
Malignant parathyroid tumors are often misdiagnosed as benign and treated improperly. Surgery is currently the gold standard for treating malignant parathyroid cancer. It’s best to completely remove the tumor during the initial surgery, so it’s important that your medical team have a suspicion of parathyroid cancer beforehand. Sometimes, the cancer returns when most but not all of the tumor is removed because cancer cells remain in the body. There’s then a higher risk of death due to complications associated with recurrence.
How common is a parathyroid cancer recurrence?
Most people with parathyroid cancer have a recurrence -- either in the same area of initial diagnosis or because the cancer spreads. Unfortunately, recurrence can be fatal. When the tumor comes back locally, it can be difficult to surgically remove because it often attaches to other vital structures like the esophagus, the breathing tube or the major blood vessels in the neck. Some then spread to the lungs, bones or liver. If the surgeon can’t remove all of the parathyroid tumor, the patient’s calcium levels won’t be regulated. The patient may then develop hypercalcemia, which can lead to fatigue, dehydration, increased infection and harm to the kidneys. Although we can relieve pain and discomfort with palliative care, the patient’s unregulated, high calcium levels eventually lead to death.
What parathyroid cancer research is underway?
We’re learning more about parathyroid cancer with six protocols that are currently enrolling patients. Two protocols are examining parathyroid tissue and hoping to predict recurrence through tumor staining. A third study is reviewing diagnostic imaging to more effectively diagnose parathyroid cancer. Fourth, we’re exploring immunotherapy as a treatment option. Fifth, with precision medicine, we’re evaluating molecular profiles of parathyroid tumors and sequencing patients’ genes to identify drugs that may specifically target the mutations. Lastly, we’re studying how circulating tumor cells can help us better monitor parathyroid cancer patients to better predict if a patient’s tumor will recur and, for those who need treatment, how the tumor will respond. By learning more about this disease, we hope to develop newer, better parathyroid cancer treatment options.
Anything else you’d like to share?
Without our patients, none of our new research would be possible. Because of patients like you who are reading this, we’re able to find new treatments. So thank you.
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