Thyroid Cancer Screening and Prevention

Thyroid cancer can often be found early. Most early thyroid cancers are found when patients ask their doctors about lumps or nodules they have noticed or when doctors find a lump during a routine checkup.

No blood tests are regularly recommended for early detection of sporadic (not familial or inherited) thyroid cancers. However, some doctors recommend that people examine their own neck twice a year to look for growths or lumps.

If you have a family history of medullary thyroid carcinoma (MTC) with or without type 2 multiple endocrine neoplasia (MEN 2), you could be at very high risk of thyroid cancer. If so, most doctors would recommend that you have genetic testing to find out if you carry the gene for MTC. This can be done by a simple blood test. 

Prevention

Most people with thyroid cancer have no known risk factors, so it is not possible to prevent most cases of this disease. Some doctors believe that the increase in thyroid cancers in recent years is due to x-ray testing of young children. This has not been proven, but it is a good idea for children to avoid x-rays that are not necessary.

Because of the genetic blood tests now available, most familial cases of medullary thyroid carcinoma (MTC) can be treated early or prevented. If you have a family history of MTC, you should see a doctor who is familiar with the latest advances in genetic counseling and genetic testing for this disease. The rest of your family (your brothers, sisters, and children) should also be tested to see if they also have mutation in the RET gene that causes MTC.

Almost all children and adults who have positive genetic tests results for the RET gene mutation will develop MTC at some time. To prevent MTC, most doctors recommend surgery as soon as possible, even in children. Removing the thyroid gland in people who carry the abnormal gene will prevent a cancer that might otherwise be fatal.

• Preventive (prophylactic) surgery - If you have inherited a defective RET gene, which can cause MTC in you and other family members, your doctor may recommend that your thyroid gland be removed by surgery (total thyroidectomy) even if it seems to be healthy. This eliminates the risk of MTC. However, it does not reduce the likelihood of adrenal or parathyroid tumors if you have multiple endocrine neoplasia, type II (MEN 2).

According to the Mayo Clinic, a healthy diet might be able to reduce your risk of thyroid cancer:

• A healthy diet - A diet high in fruits and vegetables and low in animal fat can reduce your risk of many types of cancer. The American Cancer Society recommends eating at least five servings of fruits and vegetables every day. They contain antioxidants, which protect your cells from damage. In addition, you should eat plenty of unsaturated fats (omega-3 fatty acids), especially those in salmon and other fish, because they may help protect against cancer. Keeping a healthy weight can also help protect against many diseases, including thyroid cancer.

If a nuclear power plant has an accident or is attacked, the resulting nuclear fallout could increase the risk of thyroid cancer in people living in the area. The U.S. government recommends that people who live within 10 miles of these plants store potassium iodide tablets just in case they need to protect themselves from the effects of nuclear fallout.

• Potassium iodide tablets - Potassium iodide protects your thyroid gland from iodine 131 (a component of nuclear fallout that can cause thyroid cancer) if you take it just before or right after you are exposed to nuclear fallout. However, potassium iodide does not protect you from other radioactive material. Children are most at risk from exposure to radioactive iodine, and potassium iodide is safe and effective for even very young children when they take the proper dosage.

This content has been reviewed and approved by Myo Thant, MD.