Staging and Risk Levels
Notes about Staging Systems
Papillary/Follicular Thyroid Cancer Staging (and their Variants)
Risk Levels in Papillary and Follicular Thyroid Cancer
Staging Versus Risk Level
How the Stage Affects Treatment of Papillary, Follicular, or Variants
For more about Staging and Treatments
Your doctor needs to know the stage of the disease to plan your treatment.
The stages are I, II, III, and IV (or use the common numbers 1, 2, 3, and 4). The stage refers to the cancer’s size, type, and whether and where it has spread at the time of diagnosis. Your surgery (if you have surgery) and further testing will determine the stage of your cancer.
The reference book Thyroid Cancer: A Guide for Patients notes that:
“Tumors classified as Stage I or II are typically considered to be ‘low risk’ tumors with excellent to good prognosis, whereas Stage III or IV tumors are often described as ‘high risk,’ implying a higher risk of residual disease after initial treatment, or recurrence. Fortunately, the overwhelming majority of patients will fall into Stages I and II and have an excellent prognosis with little risk for recurrence or death from their disease.”
Each type of thyroid cancer has its own staging system. Here is a brief overview. Staging is a helpful topic to discuss with your physician. Physician Guidelines from the American Thyroid Association and other professional organizations give further details. See the Physician Guidelines page, linked at the left.
Notes about Staging Systems:
- The staging systems discussed here apply only to adults with thyroid cancer. The staging system cannot be used to predict the likely course of disease in pediatric patients.
- There are many staging systems. None is perfect or captures all the essential issues that prognosticate for thyroid cancer. Also, the staging systems are static, focusing on only one point in time. They do not reassess the patient 2 years or 12 years after treatment. Because of these limitations, physicians do not rely on staging systems very much.
Patients under age 55 years are considered lower risk than patients age 55 years or older. This age was changed in January 2018 from 45 to 55 by the American Joint Commission on Cancer. However, there is no single “cutoff” point for age. A recent article noted that after age 35, thyroid cancer mortality increases with increasing age.
- In patients younger than 55 years of age: Cancer (any size) is located in the thyroid gland. It may also be present in nearby neck (cervical) lymph nodes and/or nearby neck tissue. However, it has not spread to distant sites.
- In patients 55 years of age or older: Cancer is located in the thyroid gland only and is less than 4 centimeters (about 2 inches) in size. It is not in nearby neck tissue or lymph nodes. It has not spread to any distant sites.
- In patients younger than 55 years of age: Cancer has spread beyond the thyroid and neck area (i.e., there are distrant metastases).
- In patients 55 years of age or older: Cancer is either over 4 centimeters (about 2 inches) in size or else is any size and has spread to lymph nodes or into strap muscles in the nearby neck tissue, but has not spread to distant sites.
- Cancer is in the thyroid only and is over 4 centimeters (about 2 inches) in size. It has not spread to lymph nodes, nearby neck tissue, or distant sites.
- Patients 55 years of age or younger are Stages I or II only.
- In patients 55 years of age or older: The tumor is any size and cancer has spread to nearby cervical lymph nodes and nearby neck tissue, subcutaneous tissue, larynx, trachea, esophagus, and/or recurrent laryngeal nerve but not to distant sites, or else the tumor iis larger than 4 centimeters but has not spread outside the thyroid gland other than minimally to nearby neck tissue but not to distant sites.
- In patients 55 years of age or older: Cancer has spread to other parts of the body outside the neck area, such as lungs and bones, or has extensively invaded nearby tissues in the neck (other than nearby neck lymph nodes), including large blood vessels.
The 2015 American Thyroid Association Guidelines explain risk of a recurrence or of persistent disease in people with differentiated thyroid cancer. Risk level is an important factor in decision-making regarding treatment and follow-up testing.
- Low Risk of recurrence or persistent disease means: no cancer in nearby tissue or outside the thyroid bed other than 5 or fewer small involved lymph nodes (under 0.2 centimeters), and cancer that is not one of the variants.
- Intermediate Risk (Medium Risk) means some tumor in nearby neck tissue at the time of surgery, more than 5 lymph node metastases 0.2 to 3 centimeters in size, or a tumor that’s a variant or has vascular invasion.
- High Risk means extensive tumor outside the thyroid, distant metastases, incomplete tumor removal, or a cancerous lymph node over 3 centimeters in size.
The staging determined after the initial diagnosis stays the same. However, the risk level can and often does change over time depending on your cancer’s response to the treatment received and the results found during follow-up testing and monitoring. Thus, your risk estimate may be continually modified over time. For example, a patient who is intermediate risk and has an excellent response to treatment may be reclassified as low risk.
Your treatment will be tailored to your own circumstances, including your type of thyroid cancer, whether it has spread to local lymph nodes or distant sites (lung or bone most likely), your age at diagnosis, as well as other factors.
- Surgery—usually the first step for treating any thyroid cancer
- Radioactive iodine ablation for many people with differentiated thyroid cancer
- Thyroid hormone replacement therapy for anyone who has had their thyroid gland removed (or supplemental therapy for anyone who has had partial removal of the thyroid)
- External beam radiation – for some patients
- Chemotherapy, including new targeted therapies, sometimes in a clinical trial – for some patients
- There are additional treatment modalities, such as radiofrequency ablation, and percutaneous ethanol (alcohol) injections, for selected circumstances.
Points to keep in mind:
- Treatment aims to remove all or most of the cancer and help prevent the disease from recurring or spreading.
- Treating thyroid cancer often uses two or more of these treatment approaches.
- Discuss your situation and your treatment with your physician so that you understand what is recommended and why.
The treatment your doctor will recommend depends on the stage of differentiated thyroid cancer.
The treatment recommended for you may differ from the general statements below, for reasons related to your individual circumstances.
It is very important to discuss your individual treatment plan with your doctor.
Stage I or II
- Surgical removal via a lobectomy or near-total/total thyroidectomy. A near-total/total thyroidectomy is more common than a lobectomy.
- A central compartment neck dissection may also be done. This means surgical removal of lymph nodes next to the thyroid.
- In the lowest-risk patients, surgery may be the only treatment. The cure rate for lowest-risk patients with only surgery is excellent.
- Some patients receive radioactive iodine (RAI) treatment after the thyroidectomy. The patient’s age and other factors affect the decision about radioactive iodine.
- Your doctor will prescribe thyroid hormone replacement therapy after thyroidectomy, with a dosage appropriate for a lower-risk patient.
Stage III and IV
- Surgical removal is usually a near-total/total thyroidectomy, plus a central compartment neck dissection (surgical removal of lymph nodes next to the thyroid). If the cancer has spread to other lymph nodes in the neck, a modified radical neck dissection is often done. This is a more extensive surgical removal of lymph nodes from the neck.
- Radioactive iodine treatment is generally given to eliminate any remaining thyroid tissue after surgery and to treat any undetectable cancer remaining in the neck or elsewhere in the body that takes up iodine.
- Some patients may receive external beam radiation. Some may receive chemotherapy in a clinical trial for metastatic differentiated thyroid cancer that does not take up iodine.
- According to the 2015 ATA Guidelines for Differentiated Thyroid Cancer, you should receive thyroid hormone therapy, with the dosage high enough to suppress the blood level of TSH (thyroid stimulating hormone) well below the level that is the normal range for someone without thyroid cancer.
The staging determined after the initial diagnosis stays the same. However, the risk level can change over time depending on your cancer’s response to the treatment received and the results found during the course of follow-up testing and monitoring.
For more about staging and treatments, see
Last updated: March 20, 2023