Anaplastic carcinoma of the thyroid

Definition:

An aggressive form of cancer of the thyroid gland.

Causes, incidence, and risk factors:

Anaplastic carcinoma of the thyroid is one of the most rapidly growing and invasive types of thyroid cancer. It occurs in people over 60 years and may cause obstruction of the trachea. The cause is unknown, but radiation may be a contributing factor. Thyroid function tests are usually normal. Risk factors are radiation therapy to the head or neck and age greater than 60 years old. Other types of thyroid cancer are papillary carcinoma, follicular carcinoma, medullary carcinoma, thyroid lymphoma, and metastatic thyroid cancer. Anaplastic carcinoma accounts for about 1% of all thyroid cancers. The incidence is 3 out of 10,000 people.