Radiofrequency ablation and microwave ablation

Radiofrequency ablation (RFA) uses radio waves and microwave ablation (MWA) uses microwaves to heat neuroendocrine tumour (NET) cells in the liver and destroy them. 

You have RFA or MWA using one or more special needles called needle electrodes that go through your skin into the tumour. The electric current from the probe heats the NET cells to high temperatures which destroy them. 

The heat only travels a short distance, so it doesn’t affect most of the healthy liver tissue around it.

When you might have RFA or MWA

You usually have RFA or MWA for a NET that has spread to the liver and you can’t have surgery. This could be because:

• you have several NETs in the liver
• the position of the NETs makes surgery difficult – for example if it is near a major blood vessel
• you can’t have a general anaesthetic

Doctors know that RFA and MWA work better on small liver tumours. For example, tumours that are smaller than 3cm. But doctors sometimes use ablation to treat larger tumours. Your doctor can explain whether this treatment is suitable for you.

You might have RFA or MWA alone or in combination with other treatments. You can have treatment several times. It can reduce the symptoms of a NET and help you feel better.

How you have RFA or MWA

Before treatment

You usually have an appointment at the pre assessment clinic about a week or two before your treatment. This is to prepare you for the treatment and check you are well enough to have it. 

You might have tests such as blood tests and an ECG to check your heart. 

You see a nurse during the pre assessment appointment. They explain what will happen on the day and you can ask them any questions you might have. Let your nurse or doctor know if you have any allergies or are taking any medicines that affect how the blood clots. These medicines include:

• aspirin
• clopidogrel
• arthritis medicines
• blood thinning medicines such as warfarin, rivaroxaban and dabigatran

You go into hospital on the day of your treatment or the evening before. 

You can’t eat for at least 6 hours before you have it, but you can usually drink water, tea or coffee up to 2 hours before the treatment.

During treatment

You usually have the RFA or MWA in the operating theatre or the scanning (x-ray) department of the hospital.

You have RFA or MWA under general anaesthetic, which means you are asleep. Or you might have a drug that makes you sleepy (sedation) and a local anaesthetic to numb the skin above your liver.

You can have treatment in 2 different ways. The most common way is through your skin (percutaneously). But you can also have it during a small operation called laparoscopy. A laparoscopy is when your surgeon puts a light and a camera (laparoscope) through a small cut in your tummy (abdomen). 

Your doctor (called an interventional radiologist) uses either an ultrasound scan or a CT scan to guide a special needle or probe through the skin into the tumour. The probe is an electrode that passes a radiofrequency current or microwaves into the tumour. This heats the tumour and destroys it.

Nurses monitor you during the treatment. They check your blood pressure, pulse and oxygen levels.

Your doctor removes the probe when the treatment is finished and covers the area with a dressing. The treatment takes an hour or more to complete.

After treatment

You usually stay in bed for a few hours after treatment. You can start eating and drinking once you are fully awake and feel up to it. You usually go home the next day. You should be back doing your normal activities after about a week. 

You usually have a CT scan about 6 weeks afterwards to find out how well the treatment worked.

Side effects of RFA or MWA

Most people only have mild side effects after having RFA or MWA. Side effects include:

• discomfort or mild pain
• generally feeling unwell with a raised temperature for a few days
• infection, but this is rare

Your doctor or specialist nurse gives you painkillers to take home with you. 

Some people have flu-like symptoms that start about 3 to 5 days after treatment and can last up to a week. Contact your doctor or nurse if you feel unwell after this time or if you have a temperature above 38C, as you may have an infection. 

There is a small risk of damaging the bowel or bile ducts during treatment. But this is rare because doctors use scans to help them guide the needle or probe into the tumour. 

Another risk is bleeding caused by the needle going into the liver. This is also rare. Your doctor or nurse monitors you closely during and after treatment. 

Coping

Treatment for neuroendocrine tumours can be difficult to cope with for some people. Your nurse will give you phone numbers to call if you have any problems at home.