Hepatic Cancer in Chinese: A Chapter in "Geographic Pathology"

Chinese patients display an unsually high incidience of hepatocellular carcinoma, as expressed in autopsy statistics, in hepatic biopsy specimens, in terms of ratios per 100,000 population, and with regard to standarized mortality rates. As in other ethnic groups, Chinese hepatoma patients show a pronounced numerical preponderance of male over female persons. Whether this sex difference is due to the existnece of cross-reactivity between HBsAg and a male-associated antigen remains to be confirmed. Of the Chinese patients residing abroad, those that were born in China (Idai) are at considerably higher risk of developing hepatic cancer than those born in their countries of residence (Erdai). This observation, per se, strongly argues in favor of an environmental, rather than racial, factor in the causation of such tumors. Among environmental factors suspected of contributing towards the observed inter-ethnic differences in hepatoma incidence rates, parasitic infestations appear to play no role in hepatocarcinogenesis, with the possible exception of clonorchiasis which has been implicated in cholangiocellular carcinomas. Dietary factors, hepatotoxins and alcoholism at beast are of only secondary etiological significance. Cirrhosis has been considered the most important etiological factor in the development of hepatocellular neoplasms. In Chinese patients the proportion of hepatomas arising in cirrhotic livers in many times higher than in Caucasian persons. Surveys have shown that the hepatitis-associated antigen has a high incidence of occurrence in persons of Chinese ancestry, especially those that were born in China, as well as in patients with hepatomas. It has been established that Chinese-Americans are at a very high risk for both hepatitis B virus infection and liver cell carcinoma. In addition, it has been hypothesized that in some families children will be infected with the virus by their mothers during the perinatal period, and that in some cases the infected person swill proceed through several stages (carrier state with retentions of antigen; development of chronic hepatitis; elaboration of cirrhosisis) to the development of hepatocellular carcinoma. It appears, then, that infection with the hepatitis B virus, during the earlier phases of life, is the single most important event in the eventual elaboration of hepatocellular carcinoma. The available epidemioligcal data on Chinese patients constitute a significant body of evidence in support of these conclusions.