Staging thyroid cancer

The stage of the thyroid cancer helps the doctors decide on the most appropriate treatment.

TNM staging

There are different ways of staging cancers. The most common staging system is the TNM system:

T describes the size of the tumour and whether it has spread into nearby tissues around the thyroid gland. There are four levels describing the tumour. They range from T1, where the tumour is less than 2cm and hasn’t grown outside the thyroid gland, to T4 where the tumour is of any size and has spread to nearby tissues.

N describes whether the cancer has spread to the lymph nodes close to the thyroid gland. There are two levels: either the lymph nodes aren’t affected, or the cancer has spread to lymph nodes close to the gland or in the neck or chest area.

M describes whether or not the cancer has spread to other parts of the body, such as the lungs or the bones (metastatic or secondary cancer).

Number stages

Doctors often combine the information from the TNM system into an overall number stage, for example stage 2A.

Unlike most cancers, thyroid cancer is also often staged according to:

• the age of the person
• the type of thyroid cancer they have.

The staging of thyroid cancer can appear complicated, so it might help to get your doctor or nurse to explain the type and stage for you.

We have more information in our section on the detailed staging of thyroid cancer|.