Condition: Thyroid Cancer

Cancer of the thyroid affects the small butterfly-shaped gland that sits in the base of the neck. There are several types of thyroid cancer but most are highly curable with the appropriate treatment.

Thyroid cancer develops when the DNA of thyroid cells changes (mutates) causing cells to grow and reproduce uncontrollably. Exactly what causes this isn’t known, but several factors are known to be associated with thyroid cancer including:

• Age and sex – women in their 40s and 50s and men in their 60s and 70s have a higher risk, and women are 3 times more likely to be diagnosed with thyroid cancer than men
• Inheriting certain conditions or faulty genes
• A family history of thyroid disease or thyroid cancer
• Radiation exposure
• A diet low in iodine
• Being obese (having a BMI of 30 or higher)
• Having a benign thyroid condition including an enlarged thyroid (goitre), Hashimoto's disease or nodules (adenomas)

Early-stage thyroid cancer rarely causes symptoms, or symptoms are mild and few.

The most common symptom of thyroid cancer is a painless lump or swelling in the neck. However, it’s important to know that most thyroid lumps are benign (non-cancerous), and only around 1 to 2 in 20 are cancerous.

Other symptoms of thyroid cancer to look out for include:

• Vocal changes, especially hoarseness that doesn’t go away after a few weeks
• A sore throat or difficulty swallowing that doesn’t improve
• Pain in your neck
• Swollen lymph nodes in your neck
• Facial redness (flushing)
• A cough 
• Diarrhoea

How serious thyroid cancer is depends on the type of thyroid cancer you have, the size of the tumour, if it has spread to other areas of the body, and your general health.

The main types of thyroid cancer are:

• Differentiated – Most thyroid cancers are differentiated cancers. They are divided into papillary, follicular and Hürthle/oncocytic cell. In these types of thyroid cancer, cells usually look a lot like normal thyroid tissue cells when examined under a microscope and grow slowly.
• Medullary -  This type of thyroid cancer is rare accounting for around 2% of diagnoses. Around a quarter of people with this type of cancer have a family history of the disease.

• Anaplastic – This is the most aggressive type of thyroid cancer. It can grow quickly and often spreads to tissue surrounding the thyroid and other parts of the body. This type is also rare, accounting for less than 1% of thyroid cancer diagnoses.

If you have any symptoms of thyroid cancer, it’s important to see a doctor as soon as possible so that you can get a diagnosis and start treatment if it’s needed.

Tests used in the diagnosis of thyroid cancer include:

• Blood tests
• An ultrasound scan of your neck
• A biopsy of the thyroid gland

You may need further testing if you are diagnosed with thyroid cancer. Tests may include imaging scans such as CT or PET scans.

If you’re diagnosed with thyroid cancer, your specialist will prepare a treatment plan for you. The treatment you will be recommended will depend on the type of thyroid cancer you have, how large it is and if it has spread.

Your treatment plan may include:

• Surgery – a full or partial thyroidectomy (thyroid removal). Some lymph nodes in the neck may also need to be removed if the cancer has spread.
• Hormone therapy – if you have part or all of your thyroid removed, hormone therapy is needed to replace hormones produced by the gland. Hormone therapy can also help stop the cancer from coming back.
• Radioactive iodine treatment – radioactive iodine treatment uses radiation taken as a tablet or drink to kill cancer cells. You may be given this treatment after surgery to kill any remaining cells or to stop the cancer from coming back, or if the cancer has spread.
• Targeted drug therapy – targeted medicines aim to stop cancer growing if other treatments are not an option or have stopped working, or if the cancer has spread.
• Radiotherapy – radiotherapy uses high-energy rays of radiation to kill cancer cells and stop them from growing. You may have radiotherapy if the cancer can’t be removed with surgery. This is uncommon.
• Chemotherapy – intravenous or oral chemotherapy medication works to kill cancer and stop cell growth. Very few people need chemotherapy for thyroid cancer but it may be necessary if the cancer has spread to other areas of your body.