Liver Cancer – Prevention is Better than Cure
Health screening has become a norm. More and more patients are going for health screening like Pap smear, mammogram and even colonoscopy to try to detect cancer early while it is in the curable stage.
It is important to increase the awareness on liver cancer since it is one of the most common types of cancer worldwide. According to the World Health Organization (WHO) survey, liver cancer is the fifth most common cancer worldwide and the third most common cause of cancer deaths. Primary liver cancer is still very rare, as most liver cancers are related to viral Hepatitis such as Hepatitis B and C.
Unfortunately, we are living in an area with one of the highest incident of liver cancer in the world. There are 20-100 cases per 100,000 persons annually in Asia and Africa compared to less than ten cases per 100,000 persons in the Western countries. The occurrence of liver cancer increases with age. In Western countries, it is rare for liver cancer to occur before the age of 50. Whereas in high risk countries, liver cancer can occur at a younger age – some even before the age of 20. The difference is attributable to the endemic nature of Hepatitis B and C infections in these areas.
About 75% to 80% of liver cancer worldwide is attributed to chronic Hepatitis B (50% to 55%) or Hepatitis C (25% to 30%). It takes 30 to 50 years for liver cancer to develop after a patient is infected with Hepatitis B or C. The annual incidence of liver cancer in Hepatitis B carriers is 0.5%. The relative risk of liver cancer is about 100:1, which means that a Hepatitis B carrier is 100 times more likely to get liver cancer than an uninfected person. The incidence in patients with known cirrhosis is 2.5% per year. However, this is not true for Asian Hepatitis B patients without cirrhosis. The annual incidence starts to exceed 0.2% at the age of 40, irrespective of cirrhosis or disease activity.
Studies have shown that surveillance can detect cancer when they are smaller and less likely to have extended beyond the point where intervention is less likely to make a difference. A large-scale study conducted in China showed that the surveillance of Hepatitis B carriers with six monthly blood tests (alpha fetoprotein) and ultrasound reduced liver cancer-related mortality by 37%.
About 12,000 Taiwanese men with Hepatitis C positive are prone to a 20-fold increased risk of liver cancer compared to Hepatitis C negative subjects. However, the treatment for Hepatitis C has improved over the recent years. The chance of eradication of Hepatitis C virus varies from 40% to 80% depending on the sub-type of the Hepatitis C virus. Eradication of the virus will stop the progress of the disease and prevent the liver from progressing to the stage of cirrhosis and liver cancer.
Another common liver disease that could lead to liver cirrhosis, which we often overlook, is the fatty liver. It is a general acceptance whereby fatty liver represents the liver manifestation of the metabolic syndrome. The hallmarks include obesity, hypertension, diabetes, hypertriglyceridemia, and a low level of high density lipoprotein (HDL) cholesterol. There are approximately 47 million individuals in the United States with metabolic syndrome, and more than 80% in this category have fatty liver. Fibrosis (inflammation and hardening of liver) severity increases over time in patients who have fatty liver. About 40% of patients, followed up in five years, showed progression of the disease. Fibrosis progression is significantly associated with obesity and high Body Mass Index (BMI). The risk of progression to cirrhosis is estimated to be approximately 20%.
Surprisingly, the only medically proven treatment for fatty liver is as simple as weight loss. Weight reduction of 10% or more has been shown to correct the liver function test and decrease liver swelling.
Dr. Chin Kuen Loong
MBBS(Aust.), MRCP(UK), MRCPE, Fellowship in Gastroenterology (Mal.)
Medical treatment has moved forward and changed its face over the last few years. We are now moving into the era of preventive medicine.
Tags:LohGuanLye Specialists Centre, Liver Cancer, Malaysia