What is anaplastic thyroid cancer?

Anaplastic thyroid cancer is the rarest type of thyroid gland cancer. It is more common in women and mostly affects people over the age of 60. It usually grows more quickly than other types of thyroid cancer.

About 1 to 2 out of 100 (1 to 2%) of thyroid cancers are anaplastic.

We also have information about follicular, papillary and medullary thyroid cancer.

Related pages

Symptoms of anaplastic thyroid cancer

The most common symptom of anaplastic thyroid cancer is a mass or lump in the neck that grows quickly. Often, other symptoms often develop within a few weeks, including:

  • difficulty breathing – caused by the thyroid tumour pressing on the windpipe (trachea)
  • difficulty swallowing – caused by the thyroid tumour pressing on the gullet (oesophagus)
  • a hoarse voice that has no obvious cause and does not go away after a few weeks
  • a cough
  • a feeling of pressure or discomfort in the neck.

Causes of anaplastic thyroid cancer

We do not know what causes anaplastic thyroid cancer. But having an enlarged thyroid gland or a history of follicular or papillary thyroid cancer may increase your risk.

Diagnosing anaplastic thyroid cancer

You usually start by seeing your GP, who will examine you. They will refer you to a hospital for specialist advice and treatment if they:

  • are unsure what the problem is 
  • think your symptoms could be caused by cancer. 

If they think it could be cancer, you should be seen at the hospital within 2 weeks.

At the hospital, the doctor will ask you about your general health and any previous medical problems. They will also examine you. You may have some of the following tests:

  • Blood tests

    It is not possible to diagnose thyroid cancer through a blood test. But you may have blood tests to check your thyroid function and general health.

  • Ultrasound scan

    An ultrasound scan uses sound waves to build up a picture of the inside of the neck and the thyroid gland. Your doctor will also check the lymph nodes in your neck to see if any of them are abnormal. This is because thyroid cancer can spread to the lymph nodes.

  • Fine needle aspiration (FNA)

    A doctor gently passes a small needle into the lump or swelling in your neck. Sometimes the doctor uses an ultrasound scan to help guide the needle to the right area. Then they take a small sample of cells and examine it under a microscope to check for any abnormal cells.

    If an FNA does not collect enough cells, it may need to be done again.

  • Core biopsy

    You may need to have a core biopsy. You have a local anaesthetic to numb the area. Your doctor uses a needle to take a sample of tissue. The needle is slightly bigger than the one they use for the FNA. They may use an ultrasound scan to guide the needle to the right area. You may have a core biopsy if: 

    • the FNA does not collect enough cells
    • the results from the FNA are not clear enough to make a diagnosis.

Further tests for anaplastic thyroid cancer

If the tests show that you have thyroid cancer, your doctor may want to do some further tests. These are to find out the size and position of the cancer and whether it has spread to other parts of the body. This is called staging. Knowing the stage of the cancer helps you and your doctor decide on the best treatment for you. These tests may include the following:

  • CT scan

    A CT scan takes a series of x-rays. These build up a three-dimensional picture of the inside of the body.

  • MRI scan

    An MRI scan uses magnetism instead of x-rays to build up a detailed picture of areas of your body.

  • PET Scan

    PET scan uses low-dose radioactive glucose (a type of sugar) to measure the activity of cells in different parts of the body.

  • Vocal cord check

    Only a few people with anaplastic thyroid cancer can have surgery to remove the thyroid gland. If you do have surgery, you may need to have your vocal cords checked before and after your operation This is because the nerves that control your vocal cords are close to the thyroid gland, and can be damaged during surgery..

Staging of anaplastic thyroid cancer

The stage of a cancer describes its size and whether it has spread beyond the area of the body where it started.

We have more information about the staging of anaplastic thyroid cancer.

Treating anaplastic thyroid cancer

The treatment you have will depend on the stage of the cancer and your general health.

A team of specialists will meet to discuss the best possible treatment for you. This is called a multidisciplinary team (MDT).

For many people, anaplastic thyroid cancer has already spread when it is diagnosed. In this case, treatment aims to try and slow the growth of the cancer. This may improve your symptoms and give you a better quality of life.

Treatments may include:

  • Radiotherapy

    Radiotherapy is often the main treatment for ATC. It may be given on its own, after surgery or with chemotherapy.

  • Chemotherapy

    Chemotherapy can be given on its own or with surgery or radiotherapy.

  • Targeted therapy

    Targeted therapy drugs are sometimes used to control anaplastic thyroid cancer. They target something in or around the cancer cell that is helping it grow and survive.

  • Immunotherapy

    Immunotherapy drugs are sometimes used to help control anaplastic thyroid cancer.

  • Surgery

    Surgery is only suitable for a small number of people with anaplastic thyroid cancer. Your doctors may recommend it if the cancer is has not grown outside the thyroid gland.

  • Controlling symptoms

    As well as treatment to try to slow the growth of the cancer, you will be offered supportive (palliative) care, with medicines and support to manage any symptoms.

We have more information about treating anaplastic thyroid cancer.

After treatment for ATC

Your doctor and nurse will arrange follow up appointments with you to check how you are. They will examine you, and may arrange some tests, including blood tests.

They will give you advice about controlling any symptoms you may have and what to expect. They can also give you emotional support and refer you to any other types of support you may need.

Getting support

You may have lots of different emotions after being diagnosed with cancer. You may get anxious between appointments. This is natural. It may help to get support from family, friends or a support organisation.

Macmillan is also here to support you. If you would like to talk, you can:

  • Call the Macmillan Support Line on 0808 808 00 00.
  • Chat online to our specialists.
  • Visit our thyroid cancer forum to talk with people who have been affected by thyroid cancer, share your experience, and ask an expert your questions.

Other useful organisations

There are also other organisations that can give you information and support. These include:

About our information

  • References

    Below is a sample of the sources used in our thyroid cancer information. If you would like more information about the sources we use, please contact us at cancerinformationteam@macmillan.org.uk

    British Medical Journal. Best Practice Guidelines, Thyroid cancer. 2020.

    European Society Medical Oncology (ESMO): Thyroid cancer, Clinical Practice Guidelines for Diagnosis, Treatment and Follow-up. 2019.

    National Institute for Health and Care Excellence (NICE). TA535: Lenvatinib and Sorafenib for treating differentiated thyroid cancer after radioactive iodine. 2018. www.nice.org.uk/guidance/ta535 [accessed May 2021].

  • Reviewers

    This information has been written, revised and edited by Macmillan Cancer Support’s Cancer Information Development team. It has been reviewed by expert medical and health professionals and people living with cancer. It has been approved by Senior Medical Editor, Professor Nick Reed, Consultant Clinical Oncologist.

    Our cancer information has been awarded the PIF TICK. Created by the Patient Information Forum, this quality mark shows we meet PIF’s 10 criteria for trustworthy health information.

The language we use

We want everyone affected by cancer to feel our information is written for them.

We want our information to be as clear as possible. To do this, we try to:

  • use plain English
  • explain medical words
  • use short sentences
  • use illustrations to explain text
  • structure the information clearly
  • make sure important points are clear.

We use gender-inclusive language and talk to our readers as ‘you’ so that everyone feels included. Where clinically necessary we use the terms ‘men’ and ‘women’ or ‘male’ and ‘female’. For example, we do so when talking about parts of the body or mentioning statistics or research about who is affected.

You can read more about how we produce our information here.

Date reviewed

Reviewed: 01 June 2021
Next review: 01 June 2024

This content is currently being reviewed. New information will be coming soon.

Trusted Information Creator - Patient Information Forum
Trusted Information Creator - Patient Information Forum

Our cancer information meets the PIF TICK quality mark.

This means it is easy to use, up-to-date and based on the latest evidence. Learn more about how we produce our information.