PUBLISHED ONSeptember 03, 2020 1:00 PMByMelissa Goh
Due to the recent Covid-19 pandemic, people have started to pay more attention to their health and well-being, for good reason. If there's one thing we can take away from this period, it's to never take our health for granted again.
As we know by now, Covid-19 is caused by the coronavirus, but did you know that viruses can also be the cause of certain types of cancers?
Viruses and liver cancer
Dr Zee Ying Kiat, Senior Consultant and Medical Oncologist at Parkway Cancer Centre shared with us about liver inflammation and damage, and how a virus such as hepatitis B is linked to liver cancer.
Said Dr Zee, "Hepatitis B is a liver infection caused by the hepatitis B virus (HBV). Although viral hepatitis A, B and C can cause similar symptoms, hepatitis B and C can begin as short-term infections in some people and remain in the body to cause a lifelong infection."
World Health Organisation (WHO) has classified viral hepatitis B as a major global health problem, as "it can cause chronic infection and puts people at high risk of death from cirrhosis and liver cancer."
According to Singhealth, there are "approximately 300 million carriers of HBV worldwide, of whom 75 per cent are found in the Asia-Pacific region."
Dr Zee added: "Approximately four per cent of Singapore's population is affected by chronic viral hepatitis B infection."
So how is viral hepatitis B transmitted?
It is through blood, semen, saliva or other body secretions infected with the virus and entering the body of a non-infected person.
Dr Zee shared that people can get infected through childbirth from an infected mother to her child, and unprotected sexual intercourse with an infected partner.
Other ways include direct contact with blood or open sores of an infected person and sharing personal items such as toothbrushes or razors with an infected person.
Viral hepatitis B infection can range from a mild illness (acute hepatitis B) lasting a few weeks to a serious lifelong illness (chronic hepatitis B).
Patients suffering from acute hepatitis B "can range in severity from a mild illness with few or no symptoms to a serious condition requiring hospitalisation.
"Some people, especially adults, are able to clear the virus without treatment.", said Dr Zee. Thankfully, people who have cleared the infection cannot be infected again, they become immune to the virus.
However, Dr Zee said: "Chronic hepatitis B can cause serious health problems, including liver damage, cirrhosis (scarring of the liver), liver cancer and even death."
On liver cancer, Dr Zee mentioned that in Singapore, it is the sixth most common cancer and second most common cause of cancer-related death.
In 2018, 1,378 Singaporeans were diagnosed with liver cancer, accounting for 5.3 per cent of all cancers diagnosed that year.
Symptoms and treatments
Symptoms of liver cancer are often left unnoticed until the later stages, and in some cases, the cancer would have already spread to other parts of the body.
Dr Zee shared that cancer screenings can help doctors detect liver cancer early, where treatment is more likely to be successful.
"Unlike colorectal and breast cancer screening, there is no specified age for liver cancer screening. Indication for screening is based on non-age related risk factors (eg. chronic HBV)" Said Dr Zee.
He added: "For people at higher risk of liver cancer due to cirrhosis (from any cause), chronic hepatitis B infection (even without cirrhosis), some experts recommend screening for liver cancer with regular alpha-fetoprotein (AFP) blood tests and ultrasound scans of the liver."
On the symptoms to watch out for, it includes unexplained weight loss, loss of appetite, feeling full after a small meal, nausea or vomiting.
You could also feel a fullness under the right side of the ribs, indicating a possibility of an enlarged liver. Abdominal pain, itching, and yellowing of the skin and eyes (jaundice) should also be signs to look out for.
Dr Zee said: "Treatment for liver cancer varies for different stages, liver function and the patient's general health."
The main treatments used are:
a. Surgery to remove the affected part of the liver or to transplant the liver
b. Tumour ablation where a current is passed through the tip of a needle-like probe inserted into the tumour, thereby heating the tumour and destroying the cancer cells
c. Chemoembolization therapy where substances are injected directly into an artery in the liver to attack cancer cells and reduce blood flow to a tumour in the liver
d. Radioembolization therapy where small radioactive beads are injected into an artery in the liver, near the tumour, thereby destroying cancer cells
e. Chemotherapy where drugs are administered by mouth, into a vein or into an artery that leads to the tumour in the liver, in order to attack cancer cells
f. Targeted therapy to block the action of proteins that help tumour cells grow or help tumours form new blood vessels to feed itself, thereby stopping the growth of cancer cells
g. Immunotherapy to activate a patient’s own immune system to find and destroy cancer cells.
Prevention of liver cancers and cure
In the case of hepatitis B-related liver cancer, Dr Zee said that people can prevent it by reducing exposure to known risk factors for this disease. It includes getting vaccinated against and treating viral hepatitis B infection.
Dr Zee shared: "After the vaccine is given, the body makes antibodies that protect against the virus." He also assured that the hepatitis B vaccine is safe and effective.
As for prevention against other types of liver cancers, one should limit alcohol and tobacco use, as well as the exposure to cancer-causing chemicals such as aflatoxins found in mouldy peanuts, wheat, soya and grains.
Maintaining a healthy weight and treating inherited conditions like haemochromatosis where the body accumulates excessive iron, are other preventive measures against liver cancer.
While there are no specific anti-viral treatments for acute hepatitis B, doctors usually recommend rest, adequate nutrition and fluids during this short-term infection. However, there are some patients that may need to be hospitalised, said Dr Zee.
As for chronic hepatitis B, several medications have been approved with the aim of controlling the virus and preventing further damage to the liver. However, not every person with chronic hepatitis B will need to be on medication.
This article was brought to you in partnership with Parkway Cancer Centre.