According to the Malaysian National Cancer Registry Report 2007-2011, liver cancer is amongst the top ten most common cancer in Malaysia. However, not all cancers that affect the liver are considered primary liver cancer. Cancers that begins in another area of the body or organ and later on spreads to the liver is called metastatic cancer rather than liver cancer.
To better understand liver cancer, we have to first understand the organ itself. The liver is the single largest internal organ in our body and are made up of mainly cells called hepatocytes (70-85% of liver mass). Other cells that in the liver includes, cells that line its blood vessels and cells that line small tubes in the liver called bile ducts. The bile ducts extend out of the liver and carry bile from the liver to the gallbladder or directly to the intestines.
These different types of cells in the liver can form different types of cancer. The most common type of liver cancer is hepatocellular carcinoma (HCC), which begins in the main liver cell, hepatocyte, can have different growth patterns:
- Begins as a single growth in the liver and grows larger, and in the advanced stage, spreads to the other parts of the liver.
- Begins as many small cancer nodules within the liver instead of one single tumour.
This type of cancer occurs often in people with chronic liver diseases such as cirrhosis, typically caused by hepatitis B or hepatitis C infection.
In most cases, symptoms of primary liver cancer are often left unnoticed until the cancer is at an advanced stage. When signs and symptoms do appear, they may include:
- Unintended weight loss
- Loss of appetite
- Abdominal swelling
- Upper abdominal pain
- Nausea and vomiting
- Fatigue (often tired and feeling weak)
- Jaundice (yellowing of the skin the whites of your eyes)
- Itchy skin
Upon diagnosis, the stage of liver cancer describes the severity or the advancement of the cancer. Cancer staging is one off the important factors for the oncologists determine a treatment plan and predicting a patient’s outlook.
Before deciding on a treatment plan, the patient’s general health will be taken into consideration as well. The primary goal of treatment is to remove the cancer entirely through surgery. However, this option is limited to the growth and location of the tumour. A liver transplant surgery could also be considered to remove the diseased liver and replace it with a healthy liver from a donor. This option is only possible for patients with early-stage liver cancer.
Localised treatments for liver cancer is an option where the treatment is administered directly to the cancer cells or the area surrounding the cancer cells. There are various types of localized treatments, such as,
- Radiofrequency ablation. Using an ultrasound or CT scan as a guide, one or more thin needles are sued to make small incisions in the abdomen to reach the tumor. It is then heated with an electric current to destroy the tumour.
- Cryoablation. As opposed to radiofrequency ablation, this method uses extreme cold to destroy cancer cells. An instrument (cryoprobe) containing liquid nitrogen will be injected directly into the cancer cells with the guide of an ultrasound.
- Injecting alcohol into the tumor. During alcohol injection, pure alcohol is injected directly into tumors, either through the skin or during an operation. Alcohol causes the tumor cells to die.
- Chemoembolization is a type of chemotherapy treatment that injects chemotherapy drugs directly into the liver.
- Placing beads filled with radiation in the liver. Tiny beads that contain radiation are placed directly in the liver where they can deliver radiation directly to affected area.
Cyberknife is another option to treat liver cancer. A specialized type of radiation therapy, called stereotactic radiosurgery, involves focusing beams of radiation simultaneously at one point targeting the cancer in the liver. CyberKnife is also appropriate for patients who cannot undergo liver cancer surgery for primary or metastatic liver cancers due to their weak medical condition, or who don’t want to undergo surgery.
Targeted Therapy, Kinase Inhibitor Drug is a targeted drug that works in 2 ways. It helps block tumors from forming new blood vessels, which they need to grow. It also targets some of the proteins on cancer cells that normally help them grow.
In Malaysia, liver cancer is one of the top 5 most common cancer amongst men and the Chinese ethnicity are more prone to getting this disease (Malaysia National Cancer Registry, 2007-2011).
The exact cause of liver cancer is unknown, but in most cases, they are associated with damage and scarring of the liver known as cirrhosis. This could be due to many reasons,
- drinking excessive amounts of alcohol over many years
- having long-term hepatitis B or hepatitis C infection
- an inherited disorder in which iron levels in the body builds up over the years
- long-term liver disease in which the bile ducts in the liver become damaged
Obesity is also one of the risk factor to developing liver cancer as it could produce non-alcoholic fatty liver disease.