The thyroid is located right below the adam's apple, at the base of the neck. The thyroid's main function is to create hormones that regulate the body's temperature, weight and metabolism, heart rate, and blood pressure. Thyroid cancer occurs when the cells in the thyroid mutate and become cancerous. The cause of thyroid cancer is unknown, however, there are risk factors that make some people more susceptible to developing it. Also, thyroid cancer symptoms can be hard to spot, and are only noticed when the disease has progressed. The chances of women getting thyroid cancer is three times more likely than men. Having a family history of goiter, which is the enlargement of the thyroid gland, can cause a person to be at risk of getting thyroid cancer. Another risk factor is if there is a history of having thyroid cancer in the family. Also, being exposed to radiation at high levels have shown to cause thyroid cancer. Older people and Caucasians are more likely to get thyroid cancer than any other age or race. Although thyroid cancer does not manifest with many signs and symptoms during the early stages, as it gets larger, there are several symptoms that show up. As the tumor grows, it can press on the voice box and cause hoarseness or other voice changes. People can also experience difficulty in swallowing, and often accompanied by pain in the throat or neck. Thyroid cancer can also be detected when a person notices a nodule or visible bump on their neck. Because thyroid cancer is not common in the United States, doctors will most likely try to find other reasons for the symptoms. If thyroid cancer is suspected, a biopsy is done to the nodule to determine if it is benign or is indeed cancerous. When the symptoms do point to thyroid cancer, the customary treatment is surgery. Radiation therapy and chemotherapy are other treatments that are used. If the cancer has not spread, there is a large chance of success. Survival rates vary depending on how large the tumor was, the person's age, and whether it has spread. For the most part, long-term survival rates are high for people who develop thyroid cancer.