How Common is Thyroid Cancer?
While nodules in the thyroid are common, the proportion of nodules that are cancerous is low. By age 50, approximately 70% of women will have thyroid nodules. The vast majority—up to 95%—of these nodules are benign, meaning that they are not cancerous.
Thus, there is no reason to panic if you feel a lump in the area of your thyroid or if your doctor tells you that you have a nodule. However, it is a good idea to get nodules checked out. If you do have a nodule, your doctor will look at the size of the nodule, see how fast it grows over time, and likely view the nodule using ultrasound imaging to see if further investigation is necessary or if the nodule can just be watched over time.
Risks factors for thyroid cancer include a family history of thyroid cancer and exposure to radiation, such as in the treatment of conditions like lymphoma or from living near a nuclear power plant. While thyroid nodules are more common in women, the risk of nodules being cancerous is greater in men. In general, the risk also increases as people age.
Treatment of Thyroid Cancer
The most common types of thyroid cancer have an excellent prognosis, as they are very treatable and often curable. In many cases, the only treatment needed is removal of the thyroid gland. If nearby lymph nodes are affected, those will be removed as well.
In certain cases, a person may need additional treatment in the form of an oral medication called radioactive iodine (RAI), which is given several weeks after surgery to eliminate any remaining thyroid cancer tissue. Once the thyroid gland has been removed for any reason, a patient takes a daily thyroid hormone supplement, which is chemically identical to the thyroid hormone produced by the body. The supplement is dosed according to individual’s needs and is very well tolerated.
The doctors involved in thyroid cancer are surgeons and endocrinologists, and if RAI is administered, a nuclear medicine specialist. Medical and radiation oncologists are only involved in rare cases of advanced, recurrent, or persistent disease.
Recent Advances in Testing for Thyroid Cancer
If a nodule requires examination, your doctor will use ultrasound imaging to view the nodule and may perform a fine-needle biopsy, which is a simple office procedure in which a thin needle is inserted into the nodule to extract some cells. The cells will be examined under a microscope to look for signs of cancer.
Because of recent technologic advances, the cells that are removed by biopsy now can be sent for specific genetic testing to better determine if thyroid nodules are cancerous. Nodules that previously were in a grey area in terms of cancer risk can be more specifically stratified by risk, helping patients and their doctors make decisions about management.
American Thyroid Association. Cancer of the Thyroid. June 4, 2012. http://www.thyroid.org/cancer-of-the-thyroid-gland/. Accessed January 23, 2015.
National Cancer Institute. SEER Stat Fact Sheets: Thyroid Cancer. http://seer.cancer.gov/statfacts/html/thyro.html. Accessed January 23, 2015.