Ablation therapies for liver cancer

Ablation therapy destroys liver cancer cells while trying to avoid damaging as much of the surrounding liver tissue as possible.

The 3 types of ablation therapy used for liver cancer are radiofrequency ablation (RFA), microwave ablation (MWA) and percutaneous ethanol injection (PEI).

RFA and MWA use heat to destroy cancer cells or tumours. The heat is made by electrical currents (RFA) or electromagnetic waves (MWA) that pass through a special needle placed directly in the liver.

Percutaneous ablation is the most common type of ablation therapy. The doctor guides the needle directly into the liver tumour through the skin and muscle of the abdomen.

Laparoscopic ablation is done through a narrow cut in the abdomen. The doctor passes special instruments through the cut to guide the needle into the tumour. Doctors use laparoscopic ablation to protect other organs that are close to the liver tumour or to get better access to a tumour.

RFA is the most common ablation therapy used for liver cancer. You may be offered RFA if:

• you can't have surgery
• you are waiting for a liver transplant and the tumour needs to be small enough to meet the transplant eligibility criteria (called bridging therapy)

RFA works best for liver tumours that are smaller than 3 cm and when there are no more than 3 tumours. RFA may also be offered to people who have one tumour that is up to 5 cm. MWA is preferred for larger tumours.

Liver tumours that are close to large blood vessels are harder to treat with RFA and MWA. The blood flowing through them cools the tissue, so the heat does not work as well to destroy the cancer cells. RFA and MWA should also not be used on tumours near the diaphragm, bile ducts or other organs (such as the gallbladder or colon) because there is a risk that they will be damaged during treatment.

Find out more about radiofrequency ablation.

PEI is a type of ablation therapy that uses concentrated alcohol. The doctor uses a needle to inject the ethanol alcohol directly into the tumour. Alcohol works by creating a chemical burn, which causes the cancer cells to die.

You may be offered PEI if you can't have surgery to treat the liver cancer. It may be used to treat tumours near blood vessels where RFA or MWA can't be used. PEI works best on tumours that are smaller than 2 cm.

PEI is not as effective as RFA or MWA for tumours that are larger than 2 cm and you need more sessions to kill the cancer cells, so it is not used as often. Sometimes PEI may be used together with RFA or transarterial chemoembolization (TACE), especially for tumours that are larger than 3 cm.

Side effects can happen with any type of treatment for liver cancer, but everyone's experience is different. Some people have many side effects. Other people have only a few side effects.

If you develop side effects, they can happen any time during, immediately after or a few days or weeks after ablation therapy. Sometimes late side effects develop months or years after ablation therapy. Most side effects go away on their own or can be treated, but some side effects may last a long time or become permanent.

Some common side effects of ablation therapy for liver cancer are:

• pain
• fever
• bleeding
• damage to nearby organs (such as the bile ducts or gallbladder)
• a collection of pus in the area where the tumour was removed (called a liver abscess)
• changes to liver function or liver failure

• pleural effusion

Tell your healthcare team if you have these side effects or others you think might be from ablation therapy. The sooner you tell them of any problems, the sooner they can suggest ways to help you deal with them.