It is known among liver specialists that hepatocellular carcinoma (HCC) among southern African blacks is quite different clinically as well as histopathologically from that in other ethnic g r o u p ~. l -~ As early as 1960, Steiner4 performed a pathological study on cirrhosis and HCC in sub-Saharan Africa, and observed more frequent poorly differentiated HCC associated with less severe cirrhosis and inflammation in blacks compared with HCC among whites in Los Angeles and Chicago. Berman's monograph on primary liver cancer published in 19515 described in detail the clinically relentless progression of the disease among Mozambican blacks. Subsequent studies have shown that hepatitis B surface antigen (HBsAg) carrier rates do not vary much among Bantu blacks,6 but there is a ninefold difference in HCC incidence between the Mozambicans living along the coast and in the inland.7 It is generally believed based on such studies that exposure to aflatoxin is the major etiological factor in certain areas in Africa and elsewhere,8 and that the degree of exposure to aflatoxin makes differences in incidence and biology of the cancer. It seemed that more investigators were interested in elucidating differences between chemically and virally induced HCC, and not too many attempts were made to determine whether hepatitis B virus (HBV)-associated HCC has any characteristic features compared with etiologically differing HCC.
In this issue of HEPATOLOGY, Shiratori et a19 report their clinical observations of 205 cases of HCC seen at the University of Tokyo Hospital in 1990 to 1993 that consisted of 173 patients with hepatitis C virus (HCV) antibodies (Ab), 25 patients with HBsAg (2 overlapping cases), and 9 patients negative for both. They analyzed various clinical and epidemiological parameters. The average age was younger in HBsAg-positive cases. Only one half of them had cirrhosis, and the remaining half had moderately active chronic hepatitis. By contrast, patients with HCV-Ab-positive HCC more fre-~~ Abbreviations: HCC, hepatocellular carcinoma; HBsAg, hepatitis B surface