There are several types of thyroid cancer:
- Anaplastic carcinoma (also called giant and spindle cell cancer) is the most dangerous form of thyroid cancer. It is rare, and does not respond to radioiodine therapy. Anaplastic carcinoma spreads quickly.
- Follicular carcinoma accounts for about 10% of all cases and is more likely to come back and spread.
- Medullary carcinoma is a cancer of nonthyroid cells that are normally present in the thyroid gland. This form of the thyroid cancer tends to occur in families. It has been linked with several specific genetic mutations. It requires different treatment than other types of thyroid cancer.
- Papillary carcinoma is the most common type, and usually affects women of childbearing age. It spreads slowly and is the least dangerous type of thyroid cancer.
Symptoms vary depending on the type of thyroid cancer, but may include:
- Difficulty swallowing
- Enlargement of the thyroid gland
- Hoarseness or changing voice
- Neck swelling
- Thyroid lump (nodule)
Treatment depends on the type of thyroid cancer.
Surgery is most often done. The entire thyroid gland is usually removed. If the doctor suspects that the cancer has spread to lymph nodes in the neck, these will also be removed during surgery.
Radiation therapy may be performed using external beam (x-ray) radiation or by taking radioactive iodine by mouth. It may be done with or without surgery.
After treatment, you need to take thyroid hormone to replace what your glands used to make. The dose is usually a little higher than what your body needs, which helps keep the cancer from coming back.
If the cancer does not respond to surgery or radiation and has spread to other parts of the body, chemotherapy may be used, but this is only effective for a small number of patients.
Thyroid Nodules, Goiter
Most thyroid nodules do not cause problems and are not cancerous. They are often hard to notice because they are so small. Lots of people have thyroid nodules that are never found or treated.
There are three kinds of thyroid nodules: solid nodules, nodules that are filled with fluid (cystic nodules), and nodules that are partially cystic. You can have one thyroid nodule or several thyroid nodules (multinodular goiter). You can also have some nodules that are solid and some that are cystic. Solid nodules may grow slowly over time. In rare cases, cystic nodules bleed, which can cause them to grow suddenly and become painful.
Thyroid nodules usually do not prevent the thyroid gland from doing its job. But sometimes a noncancerous thyroid nodule can cause:
Hyperthyroidism. Hyperthyroidism happens when one or more nodules make too much thyroid hormone. Hyperthyroidism is treated with antithyroid medicine, possibly radioactive iodine, and very rarely, surgery. Hyperthyroidism from thyroid nodules is not very common. For more information on treating hyperthyroidism, see the topic Hyperthyroidism.
Difficulty breathing or swallowing. Sometimes, one or more large nodules can press on your windpipe (trachea) or on your esophagus. These kinds of nodules have to be surgically removed.
About 5 to 10 out of 100 thyroid nodules are cancer.1Thyroid cancer is usually diagnosed and treated early, so most people do very well. For more information, see the topic Thyroid Cancer..