Liver Cancer

Hepatocellular Carcinoma (HCC)

Cancer arising from the liver cell or hepatocyte is called hepatocellular carcinoma or primary liver cancer. Most HCC occur in patients with chronic liver disease and cirrhosis due to hepatitis B or C infections. Other causes include alcohol and severe fatty liver with fibrosis. In hepatitis B cirrhosis, the risk of HCC occurs at 2 to 4% per year while in hepatitis C cirrhosis, the risk of HCC occurs at 3 to 7% per year. In Singapore, HCC is the third commonest cancer and is 3.4 times more common in men than women.

Risk factors for HCC

  • Hepatitis B carrier, especially with cirrhosis
  • Hepatitis C carrier with advanced fibrosis
  • Severe fatty liver disease with fibrosis (steato-hepatitis)
  • Liver cirrhosis due to:
    • Alcohol
    • Primary biliary cirrhosis
    • Hemochromatosis
    • Cryptogenic
    • Family history of liver cancer
  • Aflatoxin (produced by fungus in mouldy peanuts)

Can HCC be prevented?

Prevention of liver disease and the progression of liver disease to cirrhosis are important strategies to prevent or reduce HCC. Vaccination against hepatitis B at birth effectively prevents the disease. Vaccination against hepatitis C is not yet available commercially. Treatment of the underlying liver disease in suitable patients with chronic active hepatitis B and C helps to reduce the risk of HCC. Maintaining a normal body weight through diet and exercise helps to prevent obesity and fatty liver. Complete prevention is not possible in patients with chronic liver disease or cirrhosis. In such cases, detection of HCC at an “early” stage (size smaller than 5 cm) by screening is important. This is because early HCC responds better to treatment.

Some strategies to prevent or reduce HCC:

Hepatitis B

Vaccination at birth. Treatment of suitable “e-antigen+” patients with interferon or antiviral medication to achieve seroconversion. Treatment of suitable patients to suppress hepatitis B virus with medication.

Hepatitis C

Treatment of suitable patients with interferon and ribavirin to eradicate hepatitis C virus.

Fatty liver

Prevent obesity. Maintain a normal body weight through diet and exercise.

Aflatoxin

Avoid foods contaminated by moulds.

Alcoholic liver disease

Abstinence. Avoid drinking more than 40g or 4 drinks for men, and 20g or 2 drinks for women.

Diagnosis & Screening

Symptoms indicate a late (advanced) stage of disease. Weight loss, abdomen pain, liver enlargement, abdomen swelling due to water retention (ascites) and jaundice are due to a large tumor, involvement of the portal vein and liver failure. Investigations include blood tests (liver function tests, alpha-fetoprotein, hepatitis B and C markers) and CAT or MRI scans. Patients with hepatitis B and C are at risk for HCC should undergo screening by ultrasound scan and alpha-fetoprotein every 6 to 12 months.

Treatment

Several factors need to be considered before deciding on treatment options. These include liver function, tumor size, blood vessel involvement, spread beyond the liver and overall general health. A fit patient with good liver function and a tumor that has not spread should go for surgery. A patient who is not fit for surgery but has good liver function will benefit from ablative treatments such as transarterial hemoembolization (TACE) or radio-frequency ablation (RFA). TACE works by cutting off blood supply to the tumor while RFA works by “cooking” the tumor with heat.

Selective internal radiation therapy (SIRT) using Yttrium-90 microspheres is a relatively new and promising treatment. Microscopic particles laced with Yttrium-90 radiation is injected through the hepatic artery into the cancer blood vessels. The particles lodge in the cancer blood vessels and the internal radiation kills the cancer cells.

A patient who is fit for surgery but has poor liver function, or several tumors may be a candidate for liver transplantation. HCC can recur in other parts of the liver after surgery or ablative treatments because the underlying liver disease is prone to develop new HCC. Therefore close follow up is needed to detect new small HCC, that can be re-treated. Treatment of the underlying hepatitis B or C condition can help to reduce the risk of recurrence.


A 70 year old male patient with liver cirrhosis due to hepatitis C and HCC treated by radio-frequency ablation. [A] Two small HCC, before treatment, appeared white on CAT scan. [B] With RFA treatment, the tumors were “cooked” using heat from the RFA needle. The tumors were destroyed, resulting in grey areas that were “holes” filled with fluid. [C] Special needles used for radio-frequency ablation.

About the author. Dr Yap Chin Kong, is a leading Specialist and Senior Consultant in Gastroenterology, Liver Diseases and Endoscopy. He was awarded a Merit Scholarship to study Medicine at the National University of Singapore and graduated with a Bachelor of Medicine & Bachelor of Surgery degree in 1983. In 1988 he obtained his Masters degree in Medicine (Singapore) and became a Member of the Royal College of Physicians (United Kingdom). He became a Fellow of the Academy of Medicine (Singapore) in 1994 and a Fellow of the Royal College of Physicians (Edinburgh) in 2000. In 1992, he was awarded the Health Manpower Development Program Award by the Ministry of Health to pursue advanced training in therapeutic ERCP (Endoscopic Retrograde Cholangio-Pancreatography) at the Academic Medical Centre in Amsterdam, The Netherlands. After a year of extensive experience he returned in 1993 to develop endoscopy further at the Singapore General Hospital until he left for private practice in 2004. He pioneered the use of endoscopic ltrasonography at SGH for a decade. During this time, he taught many generations of medical students and post-graduate doctors. In 2002, he continued to pursue his interest in early cancers of the stomach and colon and visited the Showa University Hospital in Yokohama, and the National Cancer Centre in Tsukiji, Tokyo. He lectured and taught at workshops locally and internationally, combining the best of Western and Eastern techniques. A Master endoscopist, he developed an innovative cap-fitted gastroscopy technique that is used to help countless patients worldwide. He was President of the Gastroenterological Society of Singapore (1999 to 2003) and was President of the Asia-Pacific Digestive Week in 2003. He is currently in private practice at Mount Elizabeth Medical Centre. His broad specialist experience include advanced endoscopy techniques such as ERCP treatment of bile duct stones and pancreas diseases, endoscopic ultrasound, treatment of esophagus, stomach, colon and liver cancers, viral hepatitis and inflammatory bowel disease. He is Visiting Consultant to the National University Hospital and Kandang Kerbau Womens’ & Childrens’ Hospital where he supervises gastroenterologists-in-training and performs endoscopy for sick children.