Treatment

Treatment for thyroid cancer depends on the type of thyroid cancer you have and how far it has spread.

The main treatments are:

• a thyroidectomy – surgery to remove part or all of the thyroid
• radioactive iodine treatment – you swallow a radioactive substance that travels through your blood and kills the cancer cells
• external radiotherapy – a machine is used to direct beams of radiation at the cancer cells to kill them
• chemotherapy and targeted therapies – medicines used to kill cancer cells

You'll also need continuing care after treatment to check for and prevent any further problems.

Your treatment plan

You'll be cared for throughout your treatment by a team of healthcare professionals. Your team will recommend what they feel is the best treatment for you.

This will depend on the type of thyroid cancer you have. For example:

• papillary carcinoma and follicular carcinoma can usually be treated with surgery followed by radioactive iodine treatment
• medullary thyroid carcinoma is usually treated with surgery to remove the thyroid and often followed by radiotherapy
• anaplastic thyroid carcinoma cannot usually be treated with surgery, but radiotherapy and chemotherapy can help control the symptoms

You may want to write a list of questions to ask your healthcare team before you go to an appointment to discuss your treatment options.

Surgery

Surgery is the first treatment for most types of thyroid cancer. It may involve removing:

• part of the thyroid
• the whole thyroid
• nearby lymph glands

The operation is done under a general anaesthetic (where you're asleep). Most people are well enough to leave hospital after a few days.

You'll need to rest at home for a few weeks after surgery, and avoid any activities that could put a strain on your neck, such as heavy lifting. You'll have a small scar on your neck, but this should become less noticeable over time.

It's a good idea to talk to your surgeon about the exact operation they recommend and find out what it involves.

Radioactive iodine treatment

A course of radioactive iodine treatment is often recommended after surgery. 

This will help destroy any remaining cancer cells and reduce the risk of the cancer coming back.

Preparing for treatment

To make the treatment more effective, you'll be advised to cut down on iodine in your diet for 1 to 2 weeks before the treatment.

It's recommended that you:

• avoid all seafood
• limit the amount of dairy products you eat
• do not take cough medicines – these can contain iodine
• eat plenty of fresh meat, fresh fruit and vegetables, pasta and rice

Tell your care team if you think you could be pregnant, as the treatment is not safe during pregnancy.

Women should avoid getting pregnant for at least 6 months after treatment, and men should avoid fathering a child for at least 4 months.

If you're breastfeeding, it's recommended that you stop for a number of weeks before treatment starts. Your doctor will be able to give you more advice.

The procedure

Radioactive iodine treatment involves swallowing radioactive iodine in either liquid or capsule form. The iodine travels through your blood and kills cancerous cells.

You'll need to stay in hospital for a few days afterwards because the iodine will make your body slightly radioactive. As a precaution, you'll need to stay in a single room and will not be able to have visitors at first.

You'll be able to have visitors and go home once the radiation levels in your body have come down. Your care team will advise you whether you need to take any precautions after going home.

Side effects

Side effects of radioactive iodine treatment are uncommon, but can include:

• neck pain or swelling
• feeling sick
• a dry mouth
• an unpleasant taste in the mouth

The treatment does not affect fertility in women. Fertility can be reduced in men after treatment, but it should improve over time.

Targeted therapies

Newer medicines known as targeted therapies are being used more widely to treat several types of thyroid cancer.

These specifically target cancer cells, rather than harming healthy cells at the same time, as chemotherapy does.

These may be recommended if thyroid cancer has spread to other parts of the body (metastatic thyroid cancer) and has not responded to radioactive iodine treatment.

The 3 main drugs used as targeted therapies on the NHS for treating thyroid cancer are:

• cabozantinib
• lenvatinib
• sorafenib

Find out more from Macmillan Cancer Support about cabozantinib, lenvatinib and sorafenib.

External radiotherapy

If radioactive iodine treatment is not suitable or is ineffective, external radiotherapy may be used after surgery to reduce the risk of thyroid cancer coming back.

It can also be used to control symptoms of advanced or anaplastic thyroid carcinomas if they cannot be fully removed by surgery.

External radiotherapy usually involves treatment once a day from Monday to Friday, with a break at weekends, for 4 to 6 weeks.

Side effects of radiotherapy can include:

• feeling and being sick
• tiredness
• pain when swallowing
• a dry mouth

These side effects should pass within a few weeks of treatment finishing.

Find out more about the side effects of radiotherapy.

Chemotherapy

Chemotherapy is rarely used to treat thyroid cancer, but it's sometimes used to treat anaplastic thyroid carcinomas that have spread to other parts of the body.

It involves taking powerful medicines that kill cancerous cells. It does not cure thyroid cancer, but it may help to control the symptoms.

Find out more about chemotherapy.

After treatment

After your treatment has finished you may need to continue taking medicine to reduce the risk of further problems.

You'll also be advised to have regular check-ups to look for signs of the cancer coming back.

Medicines and supplements

If some, or all, of your thyroid gland is removed, it will no longer produce thyroid hormones.

This means you'll need to take replacement hormone tablets for the rest of your life to prevent symptoms of an underactive thyroid, such as fatigue, weight gain and dry skin.

Occasionally, the parathyroid glands can be affected during surgery. These glands are located close to the thyroid gland and help regulate the levels of calcium in your blood.

If your parathyroid glands are affected, your calcium levels may temporarily decrease. If this happens, you might need to take calcium supplements until the glands start to function normally again.

Follow-up tests

Thyroid cancer can come back after treatment, so you'll be asked to attend regular check-ups to look for signs of this.

You may need tests every few months to begin with, but they'll be needed less frequently over time.

Tests you may have include:

• a blood test – to detect substances released by cancerous thyroid cells
• an ultrasound scan – to check for signs of cancer in your neck
• a radioisotope scan – a type of scan that highlights cancerous thyroid cells

Treatment will usually need to be repeated if your cancer does come back.

Page last reviewed: Sun Aug 2022 Next review due: Wed Feb 2020