Based on data collected by the population-based Singapore Cancer Registry over the period 1968 to 1982, baseline epidemiological characteristics and incidence trends of primary liver cancer were described. This will facilitate the interpretation of future trends, especially in the light of new interventions such as hepatitis B immunisation. The primary liver cancer incidence is four times higher in males than in females, with the incidence peaked in the seventh decade. The incidence rate was higher in the Chinese than in Malays and Indians and marginally higher among foreign born than Singapore born Chinese. A general declining trend in liver cancer incidence was especially notable in the local born Chinese. Misclassification of metastatic carcinomas in the earlier years of cancer registration may have contributed to the initial higher incidence. Definitive decrease in incidence as a result of hepatitis immunisation will only be seen in another two to three decades.
Chronic hepatitis B virus (HBV) infection constitutes a major public health problem particularly in developing countries in East Asia, South-East Asia, the Pacific Basin and Africa. In Malaysia, a developing nation in the South East Asian region, the chronic HBV carrier rate varies between < 1% to about 10% depending on the ethnic group studied. The highest frequency is seen among the Chinese, followed by the Malays and lastly the Indians, with a male preponderance of between 2 : 1 and 3 : 1. Exposure to the virus among the adult population is estimated to be about 15%, 26% and 36% among the Indians, Malays and Chinese respectively. Serological study of adult chronic HBV carriers showed a frequency of HBe antigenemia of about 35%, with a significant decreasing trend with age. HBV DNA status generally correlated with the HBe status. An atypical profile of anti-HBe associated with serum HBV DNA is found in some carriers; in most instances, this is related to seroconversion from HBe antigenemia to anti-HBe. Chronic complications of HBV infection include the development of hepatocellular carcinoma (HCC), the occurrence of which closely parallel that of HBsAg carrier rate. In Malaysia, HCC is the third most common malignant neoplasm and among the 10 leading causes of death. About 80% of our HCC cases are HBV associated. All 3 ethnic groups are afflicted, the highest frequency being among the Chinese. Males show a disproportionate risk with an odds ratio of 3.93 (p < 0.0001).
Hepatocellular carcinoma (HCC) is an important cancer in Malaysia. This study aimed to determine the epidemiological characteristics and clinical presentations of patients in a multiracial population consisting of three major Asian races: Malays, Chinese and Indians.
Although alpha-fetoprotein (AFP) is regarded as the reference marker for hepatocellular carcinoma (HCC), it sometimes produces false results. The objective of this study was to see if some of the readily available laboratory markers could complement AFP to improve the laboratory diagnosis of HCC. The markers tested and their sensitivities were: CA 125, 92%; ferritin, 71.3%; CA 19-9, 69.8%; beta-2-microglobulin (B2M), 53.3%; CA 72-4, 13.6%; and carcinoembryonic antigen (CEA), 10.6%. In comparison, AFP had a sensitivity of 58.8%. CA 72-4 and CEA (at the "tumour" cut-off level of 20 ng/ml) had specificities of 100%, and AFP, 97.4%. The specificities of the other markers were less impressive: CEA, 77.8% (at the cut-off level of 5 ng/ml); ferritin, 48.6%; CA 125, 48.5%; B2M, 39.6%; and CA 19-9, 37.3%. The efficiencies of the markers for HCC, which are based on the consideration of sensitivity and specificity together, were as follows: AFP, 77.6%; CA 125, 71.3%; ferritin, 60.5%; CA 19-9, 55.3; B2M, 46.9%; CEA, 40.8%; and CA 72-4, 34.5%. The receiver-operating characteristic plots confirmed AFP to be the most efficient marker for HCC. Nevertheless, it is proposed that CA 125 be combined with AFP for HCC screening because of their excellent sensitivity and specificity, respectively: a negative result for both, or even just CA 125 alone, would indicate that the disease is unlikely while a positive AFP (which would likely occur with a positive CA 125) would make its presence highly probable. A positive CA 125 and negative AFP would be equivocal for HCC. Other markers in combination with AFP are less useful.