Anaplastic thyroid cancer (ATC) (or undifferentiated) is a form of thyroid cancer which has a very poor prognosis (14% ten-year survival rate) due to its aggressive behavior and resistance to cancer treatments.
- Thyroid lump
- Enlarged lymph nodes
Anaplastic thyroid cancer grows very rapidly and is an invasive type of thyroid cancer. It occurs most often in people over age 60. The cause is unknown. Thyroid function tests are usually normal. Anaplastic cancer accounts for only about 1% of all thyroid cancers and is a very rare disease.
- A physical examination may show a neck mass.
- A CT scan or MRI may show a tumor growing from the thyroid gland.
- A thyroid biopsy shows anaplastic carcinoma.
- An examination of the airway with a fiberoptic scope (laryngoscopy) may show a paralyzed vocal cord.
- An isotope study of the thyroid (thyroid scan) shows this mass to be "cold," meaning it does not absorb the isotope.
The prognosis of this disease is poor. Less than 5% of patients survive 5 years. Most people do not survive longer than 6 months.
This type of cancer is treated with surgery to remove the tumor, or radiation therapy, or both. Surgery may require placement of a tube in the throat to help breathing (tracheostomy). This tumor does not respond to radioactive iodine, which is used to treat other types of thyroid cancer. It usually does not responsive to chemotherapy, either. For some patients, enrolling in a clinical trial of new thyroid cancer treatments may be an option.