Staging

Staging is the process of finding out if and how far a cancer has spread. The stage of a cancer is one of the most important factors in choosing treatment options and predicting your chance for cure and long-term survival.

Staging is based on the results of the physical exam, biopsy and imaging tests (ultrasound, computed tomography scan, magnetic resonance imaging, chest X-ray and/or radioisotope scans)

Unlike most other cancers, thyroid cancers are grouped into stages in a way that considers both the subtype of cancer and the patient's age.

Stage Grouping for Papillary or Follicular Thyroid Carcinoma (Differentiated Thyroid Cancer)

Younger people have a low likelihood of dying from differentiated (papillary or follicular) thyroid cancer. The stage groupings for these cancers take this fact into account. So, all people younger than 45 years with papillary thyroid cancer, for example, are stage I if they have no distant spread and stage II if they have distant metastases beyond the neck or upper mediastinal lymph nodes.

Patients younger than 45 years:
  • Stage I:  The tumor can be any size and may or may not have spread to nearby lymph nodes. It has not spread to distant sites.
  • Stage II:  The tumor can be any size and may or may not have spread to nearby lymph nodes. It has spread to distant sites.

Patients 45 years and older:
  • Stage I:  The tumor is less than 2 cm across and has not spread to nearby lymph nodes or distant sites.
  • Stage II:  The tumor is 2 to 4 cm across and has not spread to nearby lymph nodes or distant sites.
  • Stage III:  One of the following applies:
The tumor is larger than 4 cm or has grown slightly outside the thyroid, but it has not spread to nearby lymph nodes or distant sites. The tumor is any size and has spread to lymph nodes around the thyroid in the neck (cervical nodes) but not to distant sites.
  • Stage IVA:  One of the following applies:
The tumor is any size and has grown beyond the thyroid gland to invade nearby tissues of the neck. It may or may not have spread to lymph nodes around the thyroid in the neck (cervical nodes). It has not spread to distant sites. The tumor is any size and may have grown outside of the thyroid gland. It has spread to lymph nodes in the side of the neck (lateral cervical nodes) or upper chest (upper mediastinal nodes) but not to distant sites.
  • Stage IVB:  The tumor is any size and has grown either back to the spine or into nearby large blood vessels. It may or may not have spread to nearby lymph nodes, but it has not spread to distant sites.
  • Stage IVC:  The tumor is any size and may or may not have grown outside the thyroid. It may or may not have spread to nearby lymph nodes. It has spread to distant sites.

Stage Grouping for Medullary Thyroid Carcinoma

Stage grouping for medullary thyroid carcinoma in people of any age is the same as for papillary or follicular carcinoma in people older than age 45.

Stage Grouping for Anaplastic/Undifferentiated Thyroid Carcinoma

All anaplastic thyroid cancers are considered stage IV, reflecting the poor prognosis of this type of cancer.
  • Stage IVA:  Tumor is still within the thyroid and may be resectable (removable by surgery). It may or may not have spread to nearby lymph nodes, but it has not spread to distant sites.
  • Stage IVB:  Tumor has grown outside of the thyroid and is not resectable. It may or may not have spread to nearby lymph nodes, but it has not spread to distant sites.
  • Stage IVC:  The tumor is any size and may or may not have grown outside of the thyroid. It may or may not have spread to nearby lymph nodes. It has spread to distant sites.