Facts about Thyroid Cancer

Understanding Thyroid Cancer

The thyroid is a butterfly-shaped gland located on the front of the neck, in front of the windpipe. Thyroid cancer happens when cells in the thyroid gland divide and change without their normal controls or organization. Thyroid cancer is the seventh most common cancer in people who are assigned female sex at birth. They are three times more likely to get a thyroid cancer diagnosis than people who are assigned male sex at birth.  

Confirming Your Thyroid Cancer Diagnosis

The first step in treatment is checking your thyroid cancer diagnosis. Most early thyroid cancers are found when patients see their physician because of neck lumps or swelling. Sometimes, they are also found when people have ultrasounds or CT scans for other health problems. 

Your diagnosis will be done with a biopsy, where cells from the thyroid lump or nodule are removed and carefully looked at in a lab. Next, your physician will decide the stage of your thyroid cancer. 

Staging Thyroid Cancer

Staging means finding out if your cancer has spread and how far. Correct staging helps your physician predict which treatments are most likely to control your disease or put it into remission. 

Stages of Thyroid Cancer

Physicians use Roman numerals I (one), II (two), III (three) and IV (four) to name the stages of thyroid cancer. Stage I is the least advanced, and stage IV is the most advanced. All stages can be treated. 

Different stages are used based on your age. If you’re under age 55, we only use stage I and stage II. Stages for older patients go from stage I to stage IV because thyroid cancer becomes higher-risk as you get older. 

In addition to stages, your physician will use the TNM system, which gives a letter to your stage: 

  • T (for tumor): The size of the tumor and if it has grown into nearby structures
  • N (for nodes): If the cancer has spread to nearby lymph nodes
  • M (for metastasis): If the cancer has spread to distant organs, like the lungs or liver

Staging for thyroid cancer can be complicated, but your care team will explain the results of your staging and what it means for your treatment plan. 

Staging Tests

For most people, your surgery will be part of figuring out your stage. You may also have imaging tests, like an ultrasound or a radioiodine scan. Both of these tests help your care team find out if your thyroid cancer has spread. 

If there is a question about if your cancer has spread to your lungs, your physician may have a chest X-ray done.

Types of Treatment for Thyroid Cancer

There are many treatment options for thyroid cancer. The specialists who treat you at Fred Hutch are endocrine tumor experts who use a team-based approach to choose the right treatment for every patient. They will work closely with you, your family and each other to get you back to health.

Learn About Subtypes

There are five subtypes of thyroid cancer, and your best treatment depends on which subtype you have. 

Papillary Thyroid Cancer

This type of thyroid cancer is the most common. Eighty out of 100 people with thyroid cancer have this type. It develops from thyroid follicular cells, which are cells that make thyroid hormone using iodine from the food you eat. Papillary thyroid cancer tends to grow slowly over time. If it spreads outside the thyroid, it usually goes to the nearby lymph nodes in the neck. Sometimes, it can spread further, to the lungs or the bones. The main treatment is surgery. If you need it, this type of cancer can often be treated with radioactive iodine therapy after surgery. 

Follicular Thyroid Cancer

Like papillary thyroid cancer, follicular thyroid cancer develops from follicular cells, but it is less common. About 15 out of every 100 people with thyroid cancer have this type. It tends to grow slowly over time, and it may spread to other organs, like the lymph nodes, lungs or bones. The main treatment is surgery. If you need it, this type of cancer can often be treated with radioactive iodine therapy after surgery. 

Medullary Thyroid Cancer

Only about five out of every 100 people with thyroid cancer have this type. It begins in the C cells, which make up a small part of the thyroid. Like normal C cells, medullary thyroid cancer makes a hormone called calcitonin. Medullary thyroid cancer can be more aggressive and faster-growing. It’s also more likely to spread to other parts of the body, like the lymph nodes. The main treatment is surgery. Because this type of cancer starts in C cells (not in thyroid follicular cells, where iodine collects), radioactive iodine therapy doesn’t work well. Some patients get chemotherapy as part of a clinical trial. 

One out of every four people with this type of cancer have a form that is caused by genes passed down in families. Sometimes, these people also develop other endocrine tumors, like adrenal and parathyroid gland tumors.

Anaplastic Thyroid Cancer

This type of thyroid cancer is rare. Only one or two out of every 100 people with thyroid cancer have this type. It is aggressive and can grow very quickly, moving into other structures in the neck and spreading around the body. It is the most difficult type to treat. Usually, treatments involve chemotherapy and radiation therapy, and sometimes surgery. 

Thyroid Lymphoma

This type of thyroid cancer is rare. Less than one out of every 100 people with thyroid cancers have this type. It is a very uncommon form of lymphoma — almost always a non-Hodgkin lymphoma — that begins in the immune system cells (lymphocytes) of the thyroid. It is curable and treated like other non-Hodgkin lymphomas, usually with chemotherapy and radiation therapy. 

Fred Hutch has researched and treated Thyroid Cancer for decades.


There are many resources online for learning about your disease. Health educators at the Fred Hutch Patient and Family Resource Center have compiled a list of trusted sources to help you get started.

Whether you are newly diagnosed going through treatment or know someone with cancer, our staff are available to tailor personalized resources and answer questions about support options in the community. 

Cancer Research Organizations

Our list of online resources provides accurate health information from reliable and reputable sources, like the National Cancer Institute (NCI), the American Society of Clinical Oncology (ASCO) and the National Comprehensive Cancer Network (NCCN).

American Cancer Society

American Cancer Society (ACS): Overview of Thyroid Cancer

If you have thyroid cancer or are a caregiver for someone who does, knowing what to expect can be helpful. Here you can find out all about thyroid cancer in adults, including risk factors, symptoms and how they are found and treated.

American Society of Clinical Oncology

American Society of Clinical Oncology (ASCO): Guide to Thyroid Cancer

This is ASCO's Guide to thyroid cancer. Here you can learn more about treatment, the latest research and clinical trials. 

American Society of Clinical Oncology

ASCO Answers: Thyroid Cancer

ASCO Answers is a collection of oncologist-approved patient education materials developed by ASCO for people with cancer and their caregivers. Here you can find illustrations and information on thyroid cancer.

National Cancer Institute

National Cancer Institute (NCI): Thyroid Cancer-Patient Version

The NCI is the federal government's principal agency for cancer research and training. Here you can find more information about treatment, research and coping with thyroid cancer.