The thyroid is a small, butterfly-shaped gland located in the front of the neck below the larynx (voice box). The thyroid is part of the endocrine system, which makes hormones that help regulate metabolism (the body’s transformation of food into energy), blood pressure, heart rate, temperature, and other functions.
An estimated 37,000 people are diagnosed with thyroid cancer each year in the US. Women are nearly three times more likely to develop a thyroid tumor than men. Unlike many other types of cancer, which are more common in older people, thyroid cancer occurs mainly in adults between the ages of 20 and 55. It is also one of the most curable types of cancer — approximately 97 percent of people with a thyroid tumor survive at least five years beyond their diagnosis.
The biggest known risk factor of thyroid cancer is exposure to moderate levels of external radiation at a young age. This type of radiation exposure may come from radiation in the environment or from prior radiation treatment in the head and neck area. Thyroid cancer usually first appears as a small lump or swelling, called a nodule, which can be felt on the front of the neck. Thyroid nodules are common, and the vast majority of them are benign. Other symptoms may include hoarseness, difficulty swallowing, swollen glands, difficulty breathing, pain in the throat or neck, or a cough that is not due to a cold.