Dr Foo Kian Fong, a Medical Oncologist at Parkway Cancer Centre explains what happens when cancer strikes the liver.
What is liver cancer?
It is the fourth most common cancer in Singapore among men, and the third most fatal cancer among males here.
The liver is a large organ which lies in the upper right side of the abdomen and consists of two lobes – the larger right lobe and the smaller left lobe. It is an important organ as it removes toxins from the blood, produces bile to aid in digestion, stores glycogen (sugar) and more.
Liver cancer, also known as hepatic cancer, is cancer that starts in the liver.
What are the main types of liver cancer?
1. Hepatocellular carcinoma (HCC) is the most common form. It emerges in the hepatocytes (liver cells) and usually occurs in hardened and shrunken livers (a condition known as liver cirrhosis) which have been damaged by diseases or chemicals.
HCC is more common among men over 40 years old, with more than 300 new cases diagnosed locally every year, according to data on the Singapore Liver Cancer Registry website.
2. Bile duct cancer accounts for one or two of every 10 cases of liver cancer. These are cancers that start in the bile ducts, which are small tubes that carry bile to the gallbladder.
3. Cancers that begin in blood vessels in the liver are even less common but these tumours grow rapidly and are often too widespread to be removed by the time they are detected. Treatment may help slow the rate of progression, but these cancers are especially hard to treat.
4. Hepatoblastoma is a very rare liver cancer usually found in young children below four years of age. With surgery and chemotherapy, however, the survival rate is over 90 per cent for those with early stage disease. According to the Singapore Childhood Cancer Registry, 13 cases of hepatoblastoma were diagnosed in Singapore between 1997 and 2005.
What are the symptoms and how is the cancer diagnosed?
There are often no symptoms in the early stages and thus ultrasound scans and regular blood tests tend to be the only way to spot possible early stage liver cancer.
Symptoms, when they do emerge, include weight loss for no apparent reason, lack of appetite over a period, a mass or persistent discomfort in the upper abdomen, swelling in the legs as well as jaundice (yellowing of the skin), though these symptoms may be caused by ailments other than cancer as well.
Further tests include liver function tests, physical checks for jaundice or water retention in the legs or abdomen, ultrasound scans or CT scans.
A blood test may also be conducted to determine Alpha-fetoprotein (AFP) levels. A higher than normal level of AFP in the blood may be an indication of liver cancer.
How is the cancer treated?
Early liver cancer can be cured with surgery. The reality, however, is that liver cancer is often diagnosed late, making surgery impossible in many advanced cases.
Chemotherapy or radiofrequency ablation (using directed radiofrequency waves to burn the tumour) may then be carried out.
Drugs such as Sorafenib (Nexavar®) have also given hope to and helped prolong the lives of advanced liver cancer patients, especially patients with HCC.
What can be done to prevent liver cancer?
The liver can be affected by a number of lifestyle habits, such as excessive alcohol consumption and obesity, which increases one’s risk of getting fatty liver disease and thus liver cancer.
For a healthy liver, a balanced diet and regular exercise are crucial.
Recent research also shows that up to 80 per cent of liver cancer cases worldwide are caused by the Hepatitis B virus, with Hepatitis B carrier patients more likely than others to contract liver cancer.
For Hepatitis B carrier patients, liver cancer is, therefore, preventable or curable when detected early and simply going for regular health check-ups such as blood tests and ultrasound of the liver.
By Fong Mue Chern
Tags: cancer ultrasound, common cancer, hepatitis cancer, hepatoblastoma