Hepatocellular carcinoma has been suggested as the end result of a process commencing with Australia antigen-associated hepatitis.1-4 One approach to the investigation of this suggestion is to estimate the frequency of Australia antigen (Au) in patients with hepatocellular carcinoma. The patients studied and the results obtained have been reported elsewhere5 (Table 1). The Au was detected by electro-osmodiffusion (EOD)6 in three (2.6%) of 114 patients. This frequency was not significantly different from that observed in Chinese blood donors in Singapore or in a comparable group of patients suspected of having nasopharyngeal carcinoma (Table 2).
The difference between this result and that obtained from African centers is impressive. Two explanations may be offered to account for the difference. First, EOD detects only relatively high levels of Au.7 The majority of Chinese subjects who have Au have levels detectable by EOD. It is possible that a relatively