However, some thyroid disorders, including thyroid cancer, may be stealthy. In fact, more than half of the estimated 20 million Americans with some form of thyroid disease are unaware of their condition. A good way to protect your health is to learn more about thyroid conditions, like hypothyroidism and thyroid cancer, so you can assess your risk and address any concerns you have with your doctor.
Know the Signs of Thyroid Conditions
If your thyroid gland doesn’t produce the right amount of hormones your body needs, you develop thyroid disease. An overactive thyroid releases too much thyroid hormone. Known as hyperthyroidism, this condition causes your metabolism to speed up. When this happens you may experience:
Unexplained weight lossNervousnessIrritabilitySensitivity to heatFatigueTrouble sleepingRapid heartbeatMuscle weakness
On the other hand, hypothyroidism occurs when your body doesn’t produce enough thyroid hormone, causing your metabolism to slow down. When this happens you may experience:
DepressionUnexplained weight gainFatigueMuscle weaknessConstipationDry skinHair lossInfertilityTrouble with concentration and memory
With hypothyroidism or hyperthyroidism, the thyroid can also become enlarged, so much so that you can feel or see it. When this happens, it’s called a goiter. Some goiters are diffuse, which means the entire thyroid gland is enlarged. In other cases, goiters are nodular or the thyroid has bumps in it. In most cases, lumps or bumps in the thyroid gland, known as thyroid nodules, are benign. In fact, thyroid nodules are cancerous in fewer than 10 percent of cases. There are other reasons why your thyroid gland might be larger than usual, such as an imbalance or changes in hormone levels from not getting enough iodine in your diet. Although the thyroid gland can also develop tumors, most of the time the cause isn’t cancer. “Thyroid cancer is a growth in the thyroid gland and differs from other thyroid problems, which are typically conditions resulting from changes in thyroid hormone production,” explains Christopher Sullivan, MD, an associate professor of head and neck surgery at Wake Forest Baptist Medical Center in Winston-Salem, N.C., and a thyroid cancer surgeon. Although thyroid disorders are very common, thyroid cancer is extremely rare. About 20 million Americans have some form of thyroid disease, but it’s estimated that just 60,220 people in the United States will be diagnosed with thyroid cancer this year. What’s problematic about thyroid cancer is that it typically has few warning signs. “Unlike hypothyroidism or hyperthyroidism, there aren’t really any symptoms of thyroid cancer,” says Kristen Gill Hairston, MD, MPH, an assistant professor in the department of internal medicine in the section of endocrinology and metabolism at Wake Forest Baptist Medical Center. Very large thyroid tumors may cause voice, swallowing, or breathing problems. Thyroid cancer and other thyroid conditions do have one thing in common: They’re not preventable. “Currently, there is no documented way to prevent thyroid disease or thyroid cancer,” says Dr. Hairston.
Know the Risk Factors for Hypothyroidism and Thyroid Cancer
They may not be considered preventable, but hypothyroidism and thyroid cancer share a few risk factors that could increase your likelihood of developing either condition and make you more vigilant about watching for them. Most people diagnosed with thyroid cancer are 40 or older. Although those diagnosed with hypothyroidism are typically older than 60, both conditions are more common among women than men. Exposure to radiation is another risk factor for both hypothyroidism and thyroid cancer. “Thyroid cancer is associated with a history of ionizing radiation exposure such as radiation used to treat acne or enlarged adenoids in the 1950s or mantle radiation used to treat lymphoma,” notes Dr. Sullivan. Research has shown that radioactive fallout from nuclear weapons or power plant accidents have increased children’s risk for thyroid cancer. Anyone who has received radiation to the thyroid, neck, or chest is also at greater risk for hypothyroidism. If you have a family history of thyroid disease, you’re also at greater risk for hypothyroidism. In addition, certain inherited conditions or a family history of the disease have been linked to thyroid cancer. A thyroid condition known as Hashimoto’s thyroiditis is associated with an increased risk for thyroid cancer. This autoimmune disease is also the most common cause of hypothyroidism. With Hashimoto’s, the immune system makes antibodies that damage the thyroid and interfere with its ability to release thyroid hormone. A 2013 study involving 2,478 patients revealed Hashimoto’s thyroiditis is associated with a significantly higher risk for papillary thyroid cancer, the most common cancer of the thyroid gland. “Some patients with Hashimoto’s thyroid disease have increased association of thyroid cancer, but this is still very, very uncommon,” notes Hairston.
Is It Thyroid Disease or Thyroid Cancer?
For all thyroid conditions, Sullivan says that early detection and treatment are essential. “It is not possible to tell if a lump in the thyroid is cancerous without an ultrasound exam and a fine needle aspiration biopsy,” he points out. An ultrasound can help determine if a thyroid nodule is solid or filled with fluid and provide clues about whether or not it’s cancer. For definitively diagnosing thyroid cancer, you’ll need to have a biopsy. For this procedure, your doctor will use a needle to draw out cells from the suspicious area of your thyroid. The cells will then be examined under a microscope. Sullivan notes that it’s sometimes necessary to remove a lump to determine if it is cancerous. The good news is that thyroid conditions, such as hypothyroidism and thyroid cancer, are treatable. In most cases, hypothyroidism can be completely controlled with daily medication. And, the cure rate for thyroid cancer, which typically includes removing the gland, is more than 90 percent.
