Thyroid cancer is the 20th most common cancer in the UK, accounting for 1% of all new cancer cases in 2015-2017. There are around 3,700 new cases of thyroid cancer in the UK every year, that's more than 10 cases diagnosed every day. Over the last decade, thyroid cancer incidence rates have increased by 68% in the UK. Women are more commonly affected than men. (Statistics from Cancer Research UK.)

Most types of thyroid cancer are highly treatable. Even in more complex cases, the outlook is brighter than for some common cancers and it is possible to live for longer with advanced thyroid cancer and enjoy a good quality of life. However, sometimes the usual therapies may no longer work for a patient. Until recently, the options for treating advanced thyroid cancer were limited. In the last few years, however, a new class of targeted therapies has been developed. These include tyrosine kinase inhibitors (TKIs). Examples of these are sorafenib, vandetanib, cabozantinib,  lenvatinib and selpercatinib. Currently several new drugs are being tested and will become available in the future.

The availability of these therapies varies throughout the UK. You should discuss with your doctor which treatments may be suitable for you of whether there are any appropriate clinical trials in your area.

What are targeted therapies?

Targeted therapies aim to block cancer cells by interfering with specific molecules in the cells that make them grow and divide, while doing little damage to normal cells. This is different from traditional chemotherapy which aims to stop the growth of cancer cells by blocking all rapidly dividing cells.

What are tyrosine kinase inhibitors (TKIs)?

Tyrosine kinase inhibitors (TKIs) are a type of targeted therapy. They inhibit (block) chemical messengers called tyrosine kinases in cancer cells. Blocking these messengers stops the cell from growing and dividing. They are used in the treatment of several types of cancer including liver and kidney cancer as well as thyroid cancer.

Which types of thyroid cancer may be treated with TKI drugs?

Treatment with a TKI may be an option for some types of advanced thyroid cancer, such as differentiated thyroid cancer (papillary, follicular and Huerthle cell thyroid cancer) that is resistant to radioactive iodine (RAI), i.e. ‘radioiodine refractory’, as well as metastatic, progressive medullary thyroid cancer.

What is radioiodine refractory differentiated thyroid cancer (RR-DTC)?

Differentiated thyroid cancer is usually treated with surgery and, in many cases, by one or more doses of RAI to kill off any remaining thyroid cells. This is effective in treating most patients. In a small number of cases, however, the thyroid cancer cells lose their ability to take up RAI and therefore the RAI cannot kill off the cancer cells. If this has happened, further RAI treatment will not be of any benefit. This is sometimes called non-RAI-avid disease or RAI refractory disease or 'radioiodine refractory differentiated thyroid cancer' (RR-DTC). In some cases treatment with a TKI may be an option.

What is advanced medullary thyroid cancer?

Patients with medullary thyroid cancer (MTC) are usually treated with total thyroidectomy and central node dissection. If enlarged nodes are found, removal of other lymph nodes in the lateral neck should be undertaken at the same time as the thyroidectomy. Where surgery is no longer an option due to the extent of the disease, some expert medical centres may use radioactive treatment (octreotide or MIBG). These have very few side effects and can help to reduce or control the spread of MTC. However, they are only used if tests show that they will be taken up by the tumour. External beam radiation may be offered for treatment of or locally recurrent tumours. Often the disease is confined to the neck. In a small number of cases it spreads beyond the neck. Treatment with a TKI may be an option if the disease has spread outside the thyroid gland and cannot be removed with surgery or treated with radiotherapy. RAI is not effective in the treatment of MTC.

How do I know if I may need treatment with a TKI?

If your thyroid cancer is progressing, and/or causing any symptoms like severe pain or diarrhoea, your doctor may discuss other treatment options with you. These may include additional surgery, a repeat dose of radioactive iodine, or in some cases a TKI. Your doctor may also talk to you about any available clinical trials that may be suitable for your situation.

Treatment with a TKI is not always appropriate. It will depend on a number of factors, including any other medical conditions you may have and how well you feel. The selection of a specific TKI will be determined by your individual medical and clinical situation and the availability of these drugs which varies across the UK.

How can TKIs help me?

TKIs cannot provide a cure but they can improve symptoms of the cancer by slowing down/stopping the growth of the thyroid cancer for several months, or even years. This may help manage the symptoms of your cancer and enable you to enjoy a much better quality of life.

However, TKIs can have many side effects, so the risks and benefits or taking the medication need to be discussed carefully with your doctor before starting treatment. It is important to remember that not everyone experiences these side effects, or to the same degree.

What are the side effects?

Some of the most common side effects of TKIs are:

• hypertension (raised blood pressure)
• hand-foot skin reaction (sore and red palms of the hands and soles of the feet)
• skin rashes/acne
• fatigue
• constipation
• diarrhoea
• nausea or vomiting
• loss of appetite
• sore mouth
• hair loss/hair thinning
• voice changes
• headache
• emotional changes (e.g. mood changes or depression)
• increased sensitivity to sunlight (if taking Vandetanib)

Not everyone experiences these side effects or to the same degree. They may vary according to the type of TKI being taken. If you are taking a TKI it is important you discuss any side effects with your doctor as there may be ways to manage these. Sometimes it is possible to relieve these effects by changing the dose, or by switching to another TKI.

How is TKI treatment paid for?

All drugs need a licence before doctors can prescribe them on the NHS. After approval by the EMA, new drugs still need to be submitted to the Medicines Healthcare Products Regulatory Agency (MHRA) which assessed and authorises new drugs, and the National Institute for Health and Care Excellence (NICE) which decides which drugs and treatments are available on the NHS in England and Wales.

Decisions on which drugs to license in Wales and Scotland are made separately by the respective bodies: the All Wales Therapeutics and Toxicology Centre and the Scottish Medicines Consortium. 

In England, some of the drugs are paid out of the Cancer Drugs Fund (CDF).

What is the Cancer Drugs Fund?

The Cancer Drugs Fund was established in 2010 to enable patients to access drugs that are not routinely available through NHS England.

There is a single, national list of drugs and indications that the CDF will routinely fund and standard operating procedures for administration of the fund. Applications to the fund must be made on behalf of patients by a recognised and accredited cancer specialist and must be supported by the NHS Trust's clinical cancer lead.

How can I find out about clinical trials?

There is ongoing research into further treatment options based on genetic characteristics of thyroid cancers. Your doctor and clinical nurse specialist will be able to let you know whether there are any appropriate clinical trials in your area.

Cancer Research UK maintains a clinical trials database which aims to list all cancer trials and studies in the UK. For more information please follow the link below.   

Cancer Research - Clinical Trials

More Information

Selpercatinib approved for the treatment of certain rare thyroid cancers  

Biological therapy for thyroid cancer

Macmillan - Targeted cancer drugs

The Cancer Drugs Fund

Thyroid Cancer Alliance - information for patients with advanced differentiated thyroid cancer

Updated October 2021