Treatment for liver cancer
There have been many reports of effective drug therapies for hepatocellular carcinoma (HCC or liver cancer), but so far most have only been tested in small samples of patients. At present, there is no drug or combination drugs that has proved to be an effective cure.
Currently treatments such as chemoembolisation, injecting alcohol into the tumour of radio-frequency ablation may be helpful as palliative treatments. Palliative treatments are those that provide relief or remission from the cancer but are not cures.
Surgical removal of the tumour (liver resection)
Liver resection aims to remove the tumour and the surrounding liver tissue without leaving any tumour behind. As this option is usually limited to those people with excellent liver function, ideally without cirrhosis, there are very few people eligible for it. This is usually because the remaining portion of the liver is incapable of providing the necessary support for life. For patients whose tumours are successfully removed the five year survival rate is between 21% and 57% (median 37%).
For people who have cirrhosis and HCC, an early liver transplant may be effective. If a transplant is available it is probably the best option. This is particularly true for people with tumours less than 5cm in size who also show signs of liver failure.
A transplant may be suggested if: a single liver tumour is less than 5cm across; up to three tumours are all less than 3cm across; a single tumour 5-to-7cm in size has not grown for at least six months.
People with small cancers (less than 3cm) that do not involve blood vessels generally recover well and have a less than 10% risk of HCC recurring . However, the risk of recurrence of HCC increases with the size of the original tumour. It is unlikely that a liver with tumours bigger than 5cm will actually be operated on. When tumours recur after a transplant, death invariably follows shortly afterwards.
Chemotherapy has not been particularly successful in treating primary liver cancer. A different type of chemotherapy called chemoembolisation seems to be more effective. This works by delivering the chemotherapy drug directly into the tumour in the liver. The reported response rate to chemoembolisation varies widely in clinical research and is thought to vary from 16% to 61%. The drugs are mixed with an oily substance to help them remain in the liver longer and make them more effective than standard chemotherapy.
The aim of chemoembolisation is to destroy the tumour. There are two elements to the treatment. The first involves injecting a high concentration of a chemotherapy drug directly into the tumour before cutting off the tumour’s blood supply (using small beads or a gel). Withdrawing the blood supply helps keep the drug in the liver for longer and cuts off the tumour’s food and oxygen supply.
Chemoembolisation is an invasive process and usually involves a period spent in hospital. Like chemotherapy it generally has quite a few side effects. The most commonly used drugs are doxorubicin and cisplatin.
Side effects that are common with doxorubicin and cisplatin are:
- Temporary drop in the number of blood cells made by the bone marrow, causing increased risk of getting an infection from a drop in white blood cells – leading to headaches, aching muscles, a cough, sore throat, pain passing urine or feeling cold and shivering.
- Tiredness and breathlessness due to a drop in red blood cells (anaemia).
- Bruising more easily due to a drop in platelets – possibly leading to nosebleeds, bleeding gums after teeth brushing or lots of tiny red spots or bruises on arms or legs (known as petechia).
Other common side effects include:
- Fatigue (tiredness) during and after treatment – most people find their energy levels are back to normal within 6 months to a year.
- Nausea and vomiting - This may begin a few hours after receiving treatment and last for up to a day.
- Alopecia - This is temporary and the hair will grow back once the treatment is finished.
- Sore mouth and taste change.
- Skin changes - The skin may darken, but usually returns to normal a few months after treatment.
How chemoembolisation is performed
The drug is administered via a very thin catheter (a long thin tube) inserted into the femoral artery in the groin. The catheter is guided by a microscopic camera into the main artery of the body (the aorta) and then into the liver via the hepatic artery. The branches of the hepatic artery that feed the tumour are identified by X-rays. Next the catheter is guided into the area of the tumour and the drugs are injected. The procedure takes up two hours. The process can be repeated several times if necessary.
Percutaneous Ethanol Injection
This treatment involves the injection of alcohol or acetic acid by needle directly into the tumour. It is guided by an ultrasound scan and usually carried out under local anaesthetic. The alcohol kills the cancer by dehydrating the tissue and stopping the blood supply to the cancer. This type of treatment is most useful for people who have a small number of tumours measuring about no more than 3cm across. It is not used for any tumours measuring over 5 cm. If a tumour grows back again this treatment can be repeated.
Radiofrequency Ablation (RFA)
Radiofrequency ablation (RFA) is the destruction of cancer cells by the use of heat. The heat kills the tumour cells but very little of the surrounding liver tissue is affected by this heat. This is because normal liver tissue can withstand more heat than tumour tissue. Dead tumour cells are replaced by scar tissue than gradually shrinks over time.
RFA has opened up more options for people with HCC. For those who would not be considered for aggressive surgical treatments (because of such reasons as the number of tumours, their location in the liver, problems with cirrhosis), RFA is now an option. Data about the effect RFA has on long-term survival rates is scarce. There is a reasonable amount of evidence that RFA does effectively destroy tumours and preserves healthy liver tissue though. These benefits are most noticeable in patients with cirrhosis and early-stage HCC. In most studies over half the tumours have not returned. The treatment can also be used repeatedly to treat recurrent liver tumours.
The procedure involves directing an electrical current straight into a liver tumour. The electrical current passes from a radio-frequency current generator through a collection of small needles which are placed directly in the tumour. Ultrasound is used so that the needles can be accurately placed. The heat (between 80 - 100C) melts the tissue in the surrounding area.
The procedure can be done several ways:
- Under local anaesthetic, by placing needles through the skin into the tumours. This is the least invasive possibility.
- By laparoscopy where the needles are placed in a thin tube through small holes in the abdomen under sedation or anaesthetic.
- Under general anaesthetic during open surgery.
RFA is best suited to tumours of less than 3cm as there is a limit to the volume of tissue that can be treated with current equipment. It can be used to treat many small tumours and can be repeated. If a tumour is very near a major blood vessel, it is unlikely that RFA will be possible because of the risk of severe bleeding.
The treatment is considered to be safe and well tolerated. Possible side effects are pain and occasional fever.