Thyroid Cancer Stages
A cancer’s stage refers to how large the primary tumor is and how far the cancer has spread in the patient’s body. Knowing the stage helps the care team understand the disease and develop an appropriate treatment plan. It also impacts the patient’s prognosis, or chance for a successful treatment.
TNM stages
The TNM staging system is used for most cancers.
TNM staging describes cancer based on three main factors:
- The size of the primary tumor (T) and whether it has invaded nearby tissues.
- The cancer’s spread to nearby lymph nodes (N).
- Whether the cancer has metastasized (M), or spread, to distant parts of the body.
Each TNM factor is assigned a number that reflects the extent of the cancer. Tumors (T) are scored between 1-4, nodes (N) 1-3, and metastasis (M) 0-1.
After all diagnostic and staging procedures are performed, your doctor should know the TNM stage of your cancer and be able to explain how this stage impacts your treatment and prognosis.
0 to IV stages
Often, TNM staging can be simplified into stages four stages (I-IV). For some cancers, there is also a stage 0. Larger numbers mean the cancer is more advanced and is generally more difficult to treat.
- Stage 0 reflects the presence of abnormal cells that have not spread to tissue that is immediately nearby. Stage 0 is considered precancerous, though it could become cancer in the future. This stage is also called “in-situ,” which means “in its original place.” Not all cancers have a stage 0.
- Stage I cancers are typically small and confined to the area where they began.
- Stage II and Stage III cancers have spread to nearby tissue and/or lymph nodes.
- Stage IV cancer has spread to distant areas of the body. This is also called metastatic cancer. Stage IV cancer often cannot be cured, but frequently can be managed like a chronic disease.
