Liver cancer is the fifth commonest cancer in Hong Kong. In 2021, there were 1 771 new cases of liver cancer, accounting for 4.6% of all new cancer cases. Its crude annual incidence rate per 100 000 Hong Kong population was 24. In addition, liver cancer is the third leading cause of cancer deaths in Hong Kong. A total of 1 447 people died from this cancer in 2021, accounting for 9.6% of all cancer deaths. Males are more susceptible to this disease than females, reflected by the male to female ratio for the incidence of 3.1 to 1 in 2021.
It is relatively difficult to cure liver cancer because the cancer is usually diagnosed in middle or late stage, which affects the cure rate. Prevention is always better than cure. We should get the hepatitis B vaccination, and people who carry hepatitis B should have regular follow-ups to check if there are signs of liver tumours development.
The liver is the largest organ in the body and a very important metabolic organ. It is found on the upper right of the abdomen, comprising the left lobe and the right lobe. The main functions of the liver include:
Liver cancer will develop when the liver cells begin to mutate and divide uncontrolledly. Liver cancer can be classified into primary liver cancer and metastatic liver cancer. Primary liver cancer is a malignant tumour caused by liver cells, and the commonly known ones are "Hepatocellular Carcinoma" and "Cholangiocarcinoma". Metastatic liver cancer is a liver cancer caused by the spread of cancer cells from the other organs.
There are many causes of liver cancer. Factors posing higher risks include:
55% of the liver cancer is caused by infection with hepatitis B virus. The chance of chronic hepatitis virus carriers getting liver cancer is 100 times higher than non-hepatitis B virus carriers. Hepatitis B is very common in Hong Kong. It is estimated that one tenth of citizens in Hong Kong either is hepatitis B virus carriers or had the infection. Among them, a quarter may develop cirrhosis, which may cause liver cancer.
It will take 50 to 60 years to develop liver cancer after hepatitis B virus infection. People infected with hepatitis B virus may develop chronic hepatitis in about 10 years, which may then develop into cirrhosis in additional 21 years. After that, it will take 29 years for the cirrhosis to become liver cancer. The actual progress varies among people, depending on how active the hepatitis viruses are. Research shows that the more active the viruses are, the more quickly the liver cells are damaged, accelerating the development of cirrhosis or chronic hepatitis.
The chance of chronic hepatitis B and hepatitis C carriers to get liver cancer is 150 times higher. However, liver cancers associated with hepatitis C infection are more common in Western countries.
Excessive alcohol consumption may cause alcohol-related liver hardening, which may then develop into liver cancer. The chance of hepatitis B carriers with heavy alcohol consumption getting liver cell cancer is 2 times higher than general virus carriers.
Obesity, diabetes mellitus, and other metabolic disorders may induce liver damage leading to cirrhosis and liver cancer.
Aflatoxins found in peanuts, corn, nuts and grains are proven to be a cause of liver cancer in animal experiments.
For example, inhaling PVC used in plastics manufacturing factories.
May lead to bile duct cancer.
The liver has the wonder of being able to self-repair. Even when only a small part of it remains, the liver can still function normally. As a result, symptoms of a liver cancer at its early stage are not obvious. When the tumour grows, the patient can observe the following:
Major risk factors identified for liver cancer include chronic infection with hepatitis B virus (“HBV”) and hepatitis C virus (“HCV”), cirrhosis, alcohol consumption and ingestion of food contaminated with aflatoxin (a toxin found in some food, such as mouldy peanuts and grains), although other risk factors like diabetes, obesity, smoking and certain hereditary conditions such as haemochromatosis, glycogen storage disease and Wilson’s disease are also implicated. Locally, HBV vaccination has been given to all babies born since 1984 as an important preventive measure.
To reduce the chance of getting liver cancer, it is important to get vaccinated against HBV, avoid drinking alcohol and tobacco smoking. Avoidance of unprotected sexual intercourse, sharing needles and food possibly tainted with aflatoxins and maintaining healthy diet and body weight would also help reducing the risk of developing liver cancer.
Two more widely-adopted tests for liver cancer screening are alpha-fetoprotein (“AFP”) test and abdominal ultrasonography (“USG”). AFP test and abdominal USG have their limitations and they are not 100% accurate, because the blood AFP level is frequently normal during early stage and it could also be raised in conditions other than liver cancer, while the performance of abdominal USG is more operator dependent and could be affected by factors like abdominal fatness.
Currently, routine liver cancer screening is not recommended for asymptomatic individuals at average risk.
Individuals at increased risk of liver cancer (e.g. people with chronic HBV or HCV infection, or cirrhosis regardless of cause) should seek advice from doctors to determine their need for and approach of cancer surveillance. Depending on certain criteria such as age, family history, presence of cirrhosis and other clinical parameters, periodic surveillance (e.g. every 6 to 12 months) with AFP and abdominal USG may be considered.
High-risk groups and those having the above-mentioned symptoms should consult doctors and have examinations as soon as possible. The earlier the diagnosis and discovery of the disease, the higher the chance of cure. Relevant checks for liver cancer include the following:
Alpha-fetoprotein (AFP) is being used as a tumour marker for liver cancer, and can be used for screening of liver cancer in high risk groups such as patients with liver cirrhosis, chronic hepatitis B or C. It could also be helpful to determine prognosis, monitor response to therapy and detect recurrence.
Ultrasound is used to scan the structure of the liver to confirm the size and location of the tumour. It takes several minutes or longer for conducting the procedure.
Doctors will use a fine needle to obtain tissue of the liver tumour through the skin on the right abdomen when the patient is under local anaesthesia. It is used for confirming the type of the tumour cells and examining whether they are benign or malignant. This test is usually performed together with ultrasound to ensure the needle is inserted at the precise position.
Once the patient is diagnosed to have liver cancer, doctors will generally suggest the following treatments depending on the cancer stage.
It is used to remove the tumour and the surrounding affected tissues. Removal by radical surgery suits 20% of liver cancer patients whose tumours affect only one of the liver lobes and their liver functions are normal. 3-year and 5-year survival rates are 62% and 50% respectively.
The location of the tumour is first confirmed with the help of ultrasound or computer scan. Then alcohol with 95% concentration is injected directly into the tumour with a thin needle through the skin. The highly concentrated alcohol will dry up the cells and thus kill them.
It suits patients whose tumour is smaller than 3cm or whose number of tumours is less than 3. As the injection can only wither the central part of the tumour, the neighbouring tissues still survive and keep growing. As a result, the patient has to get many injections to ensure the liver cancer cells are killed.
SBRT is an external radiation therapy that uses high energy radiation to destroy the tumour. It helps control the disease while sparing a sufficient amount of normal liver reserve. The treatment utilises multi-modality image registration, radiation treatment planning, breathing motion management and image guided radiation therapy. It has high delivery accuracy, allowing ablative doses of radiation to be delivered safely.
The treatment suits patients who are not amenable to undergo surgery or local ablative therapies or have developed recurrence despite multiple courses of TACE. Cases with hepatocellular carcinoma whose tumours are less than 5 cm in diameter have 80-90% objective response rates while the rate is between 50-70% for those with larger cancers. Improved local control and survival have been seen in patients treated with higher doses.
Targeted therapy interferes with specific targeted molecules (target) that are involved in cancer cell growth and survival, resulting in fewer side effects. Nonetheless, since some of the normal cells have similar target, targeted therapy can affect them too. Common side effects include rash, mouth sores, diarrhoea, etc.
Immunotherapy helps the immune system to better act against cancer.
Common complications observed among liver cancer patients include:
Cancer tissues cause serious damages to a patient's liver, which results in the liver being unable to removed toxins from the body. This will lead to hepatic encephalopathy, which is the main cause of death from liver cancer.
The phenomenon of liver failure leads to kidney failure, which cripples the patient's ability to discharge waste from the body.
It is common that tumour cells metastasize to lungs and bones. When it metastasizes to the peritoneum, ascites is caused. Thus, the liver cancer near the diaphragm infiltrates directly to the diaphragm and pleura, which may lead to bloody pleural fluid.
Patients need to pay attention to many things before and after surgery and during recovery. These include:
To monitor the liver functions and symptoms of recurrence. If any new symptoms are found, the doctor should be notified as soon as possible.
Foods should be easy to digest and plenty of fruit and vegetables are recommended. Try to absorb proteins (milk, eggs and lean meat) and multivitamins and limit the intake of animal oil.
Appropriate exercise but avoid over-exertion.
In patients with liver disease, accurate diagnosis of the cause of the disease can improve treatment. Although blood tests and ultrasound examination provide some clues, examination of the liver tissue provides much more valuable information for diagnosis. Liver biopsy involves the use of a special needle to obtain liver tissue through the skin. Patients with acute or chronic hepatitis, abnormal liver function tests, liver failure, cirrhosis, etc. may be candidates for liver biopsy. It can provide information for making the diagnosis, predicting the prognosis and formulating the treatment plan.
For further information please contact your doctor.
Transarterial chemoembolization (TACE) is a regional treatment for inoperable hepatocellular carcinoma. It is also indicated for patients with regional recurrence in the liver after previous resection of hepatocellular carcinoma. In some patients with critically inoperable tumour, the tumour size is reduced after repeated sessions of TACE, which then becomes resectable.
TACE involves regional infection of chemotherapy drugs (Cisplatin + Lipiodol) to concentrate the drugs in the tumour area, enhancing the cytotoxic effect on the tumour cells. Gleform, a kind of sponge, is used to block the feeding vessels of the tumour and deprive nutrient and oxygen supply, causing tumour cell death and suppressing tumour growth.
For further information please contact your doctor.
Radiofrequency ablation (RFA) is a local ablative treatment modality for liver tumours including primary and secondary liver cancer. It uses localised thermal treatment technique that causes tumour destruction by heating the tumour tissue to the temperature exceeding 60oC. The procedure can be performed through percutaneous and open approaches depending on the location and size of the tumours.
For further information please contact your doctor.
Selective Internal Radiation Therapy (SIRT) using yttrium-90 (Y90) microspheres is an internal radiation therapy for liver tumours where curative resection is not possible.
Treatment with SIRT-Y90 exploits a normal physiological process of 2 different blood supplies to liver to selectively target the tumour tissue. Following delivery via a hepatic artery catheter, Y90 microspheres become lodged in the micro-vessels of liver tumour where they have a local radiation effect. There may be some limited concurrent damage to healthy tissue caused by radiation that escapes tumour boundaries and from Y-90 microspheres that fail to become embedded in tumours. Following decay of the yttrium-90, the inert microspheres will be retained permanently in tissue.
Normally the radiation from yttrium-90 microspheres retained inside the liver tumour will not be able to penetrate beyond the abdominal wall. However, when the total dose is higher than a certain limit, there is still some concern of potential harm to other people from the secondary radiation generated.
According to Radiation Ordinance and the HA Code of Practice on Radiation Safety and Protection, the activity of yttrium-90 in a patient must be below 1.5 GBq before he/she is allowed to be discharged or travel by public transport. Therefore, all patients after receiving SIRT-Y90 must stay strictly in an isolation room to avoid radiation hazard to their family members or members of the public. Patients are forbidden to leave the isolation room until the radiation dose from their body was checked to fall below a safe limit. This may take a few hours up to a few days after SIRT-Y90, depending on the actual dose they received. In the event of death, cremation may be denied by health authorities or may be deferred for a period of time depending on residual radioactivity.
For further information please contact your doctor.