There have been many reports of effective drug therapies for HCC that have been tested in small numbers of patients. However, when taken to larger properly controlled studies they are shown to be of little value. At present there is no drug or combination of drugs that has proved to be an effective cure. However, treatments such as chemoembolisation, injecting alcohol into the tumour or radio-frequency ablation may be helpful palliative treatments. Palliative treatments are those that provide some relief or remission from the cancer but are not cures in themselves.
Curative Treatments
a) Surgical removal of the tumour (liver resection)
Surgically removing a tumour (liver resection) aims to remove the tumour and the surrounding liver tissue without leaving any tumour behind. However, as in reality this option is usually limited to those people with excellent liver function, ideally without cirrhosis, there are very few people eligible for liver resection. Even within such a carefully controlled group 10% of those operated on will die of liver failure shortly afterwards. 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 30-40%. It is by no means clear, however, that the survival rate of patients with similar sized tumours and liver function is significantly different if treated palliatively.
b) Liver Transplants
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 for people with tumours less than 4cm in size who also have signs of liver failure. People with small cancers 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 and it is unlikely that a liver with tumours bigger than 4cm will be operated on. When tumours recur after a transplant, death invariably follows shortly afterwards.
Palliative Treatments
a) Chemoembolisation
Chemotherapy has not been particularly successful in treating primary liver cancer. A different type of chemotherapy called chemoembolisation, which delivers the chemotherapy drug directly into the tumour in the liver, seems to be more effective. There is currently a trial taking place in the UK to compare chemoembolisation with standard chemotherapy. The response rate to chemoembolisation is thought to vary from 16% to 41%. The drugs are mixed with an oily substance to help the drugs remain longer in the liver and make them more effective than standard chemotherapy.
The aim of chemoembolisation is to destroy the tumour. There are two elements to the treatment: injecting a high concentration of a chemotherapy drug directly into the tumour and cutting off the blood supply to the tumour (using small beads or a gel). Withdrawing the blood supply helps keep the drug in the liver for longer and cuts off the tumours food and oxygen supply.
Chemoembolisation is an invasive process and involves staying over in hospital and like chemotherapy generally has quite a few side effects. The most commonly used drug is doxorubicin.
Side effects that are common with doxorubicin are:
- Alopecia - This is temporary and the hair will regrow once the treatment is finished
- Nausea and vomiting - This may begin a few hours after receiving treatment and last for up to a day
- Sore mouth and taste change
- Skin changes - The skin may darken, but usually returns to normal a few months after treatment
- Sensitivity to the sun
- Lethargy
Less common side effects are:
- Diarrhoea
- Changes in nails. Nails may become darker. White lines may appear on them.
Patients are warned not to become pregnant or father a child while taking Doxorubicin as it may harm the developing foetus. It is important to use effective contraception whilst taking this drug, and for at least two months after coming off it.
How chemoembolisation is performed
The drugs are administered via a very thin catheter (a long thin tube) inserted into the femoral artery in the groin. The catheter is guided by TV monitoring 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 and then the catheter is guided into the area of the tumour and finally the drugs are injected. The procedure takes up to two hours. The process can be repeated several times if necessary.
b) Percutaneous Ethanol Injection
This treatment involves the injection of alcohol or acetic acid by needle directly into the tumour guided by an ultrasound scan. It is 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 3 - 4cm across it is not used for any tumours measuring over 5 cm. If a tumour grows again this treatment can be repeated.
c) Radiofrequency Ablation (RFA)
Ablation means destroying or destruction. 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 normal 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 who would not be considered for aggressive surgical treatments because of the number of tumours, the location of the tumours in the liver, problems with cirrhosis, or inability to remove the entire tumour while leaving behind enough normal liver. Data about the effect RFA has on long-term survival rates is scarce. However, there is a reasonable amount of evidence that RFA does effectively destroy tumours and preserves healthy liver tissue. 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 radiofrequency 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 whereby 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. However 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.
