Thyroid cancer is the 8th most common cancer diagnosed and affects nearly 52,00 people a year, two thirds of which are women. Although the five-year survival rate (depending upon the type of cancer you may have) is high, with nearly 98 percent still alive at the five-year mark, nevertheless, it is a serious form of cancer, killing around 2,100 people each year. Doctors don’t really know exactly what causes thyroid cancer, which is a mutation of the cells within the thyroid.

The thyroid itself is an organ in the throat responsible for secreting essential hormones that regulate the body’s metabolic rate, heart and digestive function, muscle control, brain development, mood and bone maintenance. According to the Mayo Clinic, thyroid cancer occurs in one of four types: follicular thyroid cancer, papillary thyroid cancer, medullary thyroid cancer and anaplastic thyroid cancer, as follows:

1. Papillary thyroid cancer

Papillary thyroid cancer is the most commonly diagnosed of the thyroid cancers. About 80 percent of all thyroid cancers can be classified as papillary thyroid carcinoma. It gets its name from small, nipple-like structures that can be seen under a microscope. Papillary thyroid cancer, quite often affects younger patients from around age 25-40, and often patients have no general symptoms other than a slow growing enlargement in the neck. Papillary thyroid cancer is commonly treated, depending upon the size and severity, with partial or full removal of the thyroid plus radioactive iodine treatment. In general, the prognosis is very good, and post-diagnosis patients, after treatment, generally survive for many years, particularly if they are young.

2. Follicular thyroid cancer

Follicular thyroid carcinoma is the second most diagnosed thyroid cancer and is seen in about 10 percent of thyroid cancer patients. Follicular cells enables the thyroid to secrete hormones, and the overall survival rate is approximately 91 percent at the 5-year mark, and 85 percent at the 10-year mark, significantly lower than that of papillary cancer. While follicular thyroid carcinoma rarely spreads to the lymph nodes, they can spread to the organs of the body.

3. Hurthle cell cancer

A more rare variety of follicular thyroid carcinoma is known as hurthle cell cancer. Occurring in only about 3 percent of patients, hurthle cell carcinoma patients are generally around age 55, and a 10-year survival rate is around 75 percent for patients whose cancer has not spread, but it drops to 50 percent or lower if the cancer has spread.

4. Medullary thyroid cancer and anaplastic carcinoma

Medullary carcinomas show up in about 3 percent of diagnosed cases, while anaplastic

carcinoma make up an additional 2 percent. Both are rather aggressive, frequently spreading to other body parts, while the latter, quickly spreads to the neck and lymph nodes.

5. Thyroid cancer signs to watch out for

Thyroid cancers frequently grow slowly, and there may be no outward symptoms. But if you notice a lump in your throat, increasing hoarseness or difficulty swallowing or pain within your throat, be sure and consult a doctor.