Stage IV anaplastic thyroid cancer
Anaplastic/undifferentiated thyroid cancers are much more aggressive than the other subtypes and are all considered stage IV:
- Stage IVA: The primary tumor is contained within the thyroid gland, although it may or may not have spread to nearby lymph nodes. It has not spread to distant organs.
- Stage IVB: The tumor has spread outside of the thyroid gland, and cancer cells may or may not have been found in regional lymph nodes, but have not reached distant sites.
- Stage IVC: The cancer cells have spread beyond the thyroid gland to more distant parts of the body.