• Papillary and follicular thyroid cancers are referred to as differentiated thyroid cancer, which means that the cancer cells look and act in some respects like normal thyroid cells.
• Papillary and follicular thyroid cancers account for more than 90% of all thyroid cancers. They tend to grow very slowly.
• Their variants include columnar, diffuse sclerosing, follicular variant of papillary, oncocytic, and tall cell. Two other variants (insular and solid/trabecular) are considered to be intermediate between differentiated thyroid cancer and poorly differentiated thyroid cancer. The variants tend to grow and spread more than typical papillary cancer.
• If detected early, most papillary and follicular thyroid cancers can be treated successfully. Their treatment and management are similar and are based on staging and individual risk levels.
• Papillary thyroid cancer is the most common type of thyroid cancer. It accounts for about 80% of all thyroid cancers. Papillary thyroid cancer generally grows very slowly, but can often spread to lymph nodes in the neck. It also can spread elsewhere in the body.
• The most common variant of papillary is the follicular variant (not to be confused with follicular thyroid cancer). It also usually grows very slowly. Other variants of papillary thyroid cancer (columnar, diffuse sclerosing, and tall cell) are not as common and tend to grow and spread more quickly.
• Follicular thyroid cancer accounts for about 10-15% of all thyroid cancers. Treatment will be discussed later in this booklet. Hürthle cell thyroid cancer is a variant of follicular.
• Follicular thyroid cancers usually do not spread to the lymph nodes, but in some cases can spread to other parts of the body, such as the lungs or bones.
• Treatment for follicular thyroid cancer is similar to treatment for papillary. Hürthle cell cancer (also known as oncocytic or oxyphilic) is less likely than other differentiated thyroid cancer to absorb radioactive iodine, which is often used for the treatment of differentiated thyroid cancer.
• A protein called thyroglobulin (abbreviated Tg) is used as a marker for whether all of the differentiated thyroid cancer has been successfully removed. Determining the Tg level in your blood by periodic testing will help your doctors determine how well you are doing with your treatment. Some patients produce anti-thyroglobulin antibodies (TgAb), which are not harmful but which mask the reliability of the Tg value.

Although a cancer diagnosis of any kind can be scary, the most common forms of differentiated thyroid cancer (papillary and follicular) have a very high long-term survival rate (over 90%), especially when diagnosed early.

While the prognosis for most people with thyroid cancer is very good, the rate of recurrence or persistence can be up to 30%, and recurrences can occur even decades after the initial treatment.

It is important that you have regular follow-up examinations to detect whether the cancer has recurred. Health monitoring should continue throughout your lifetime.

More details can be found on the following webpages:

• Thyroid Nodules and their Evaluation
• Treatment and Follow-Up
• Staging and Risk Levels
• Treatment Overview
• Surgery
• Radioactive Iodine
• Low-Iodine Diet
• TSH/Thyroid Hormone Replacement
• Follow-Up Testing
• Treating Recurrent or Persistent Disease
• Clinical Trials
• Physician Guidelines
• Support and More Resources
• Support Groups
• Videos with Patients’ Stories

For more about prognosis in thyroid cancer, see

• Thyroid Nodules and Cancer – About Prognosis