Stage IV thyroid cancer
The thyroid cancer staging classification system is very similar for older patients with differentiated tumors and for those with medullary thyroid cancer. Age is not a consideration when classifying medullary cancers.
Stage IV, the most advanced stage of thyroid cancer, is further subdivided depending on where the cancer has spread:
- Stage IVA: Cancers at this stage have grown beyond the thyroid gland and may have spread into nearby tissue, or they may have spread to lymph nodes in the neck and upper chest, but not to distant sites.
- Stage IVB: The primary tumor has grown into the spine or into nearby large blood vessels. In this thyroid cancer stage, the disease may or may not have spread to lymph nodes, but has not reached distant sites.
- Stage IVC: The thyroid cancer cells have metastasized, or spread to distant sites.