Should we screen hepatitis B carriers? James Arthur DICKINSON 1 and Yuk Tsan WUN 2 1 University of Calgary, Canada, formerly from Chinese University of Hong Kong and 2 Research Committee, Hong Kong College of Family Physicians, Hong Kong Abstract Chronic Hepatitis B is a common problem, especially in Asian countries. This disease causes complications of cirrhosis and liver cancer. Therefore doctors and patients are concerned whether to treat or screen for these complications. We searched the literature for evidence to determine the risk for people with chronic hepatitis B, the evidence that treating patients changes their outcome, and the effect of screening on death rates. We found little evidence from high quality cohort studies to demonstrate the outcome of chronic hepatitis B infection. Consequently, we constructed a mathematical model to demonstrate outcome for them. The model showed that as a result of having chronic hepatitis B, men lose a mean of 7 years of life, whereas women lose only 2 years. While antiviral treatments change the serological status and reduce liver infammation, there is insuffcient information about their effect on cancer reduction. Our Cochrane review of screening for liver cancer in chronic infection shows no high quality randomised controlled trials and poor non-trial evidence. It appears unlikely that screening programs are effective in reducing mortality for this disease, a conclusion shared by other groups. Therefore, at present, doctors are limited in what we can do to change the outcome for this group of patients. © 2004 World Organization of Family Doctors Key words: carriers, cirrhosis, hepatitis B, liver cancer, screening Introduction Outside the developed countries, a large proportion of the world’s population have chronic hepatitis B infection. Although many doctors still use the term ‘carriers’ because most appear to suffer no harm, modern terminology generally prefers ‘chronic hepatitis B’ because nearly all have some degree of liver damage. In this article we use the terms interchangeably. Some of these people develop liver cancer. Because of the lack of health infrastructure in most developing countries, data are limited. However, liver cancer is probably one of the commonest cancers in the world. Hong Kong has a high quality cancer registry, which is uncommon among countries with high prevalence of hepatitis B. In 1994, liver cancer was the second commonest cause of cancer deaths among men, with 914 cases compared to 1882 cases of lung cancer. 1 It was the fourth commonest female cancer with 254 cases. As for lung cancer, most patients who develop liver cancer die as a result, 80% within 1 year. Figure 1 shows the number of new cases and incidence rates for men and women. ______________________________________________ Correspondence: Professor James Dickinson, Department of Family Medicine, University of Calgary, Canada. Email: dickinsj@ucalgary.CA Accepted for publication 27 May 2004. The incidence rates rise steadily throughout life, but the greatest number of cases is among people in their 60s, since there are fewer old people. These cancers mostly arise from among the 10% of the population who are carriers. 2 In many other countries, hepatitis C also contributes to a substantial number of advanced liver cirrhosis and liver cancer, though in Hong Kong this disease is relatively rare. 3 It is also notable that although hepatitis C studies from liver clinics demonstrate high rates of progression, studies in newly infected cohorts show much lower rates in the community. 4 It is possible that similar situations arise for hepatitis B. Most carriers are aware that they are at risk of developing liver cancer and may ask their doctors: 1. What is my risk of getting cancer or complications? 2. How will this affect my life? 3. What is my chance of dying young? 4. What can I do to change it? How should doctors respond? Many hepatologists and oncologists recommend screening with ultrasound, alpha-fetoprotein (AFP) or both, at varying intervals based on their experience of seeing many cases of cirrhosis and liver cancer. Most hospital-based specialty clinic studies include a population with more severe diseases, often with cirrhosis or even symptomatic liver disease; thus, it is not surprising that such patients Asia Pacifc Family Medicine 2004;3: 1-6 Lecturer http://www.apfmj.com 1