We analyzed the importance of 'meshwork pattern', a sign representing severe irregularity on the intra-hepatic echogram, in hepatitis B virus (HBV)-related chronic hepatitis and cirrhosis, as a risk factor for development of hepatocellular carcinoma (HCC). Two hundred and thirty-one patients (143 men and 88 women) with HBV-related chronic hepatitis and cirrhosis who visited our hospital from January 1993 to December 1994 were enrolled in this study. Since enrollment, abdominal ultrasonography had in principle been performed every 3 months for cirrhotic patients and every 4-6 months for patients with chronic hepatitis for HCC screening. Cumulative HCC incidences in patient groups positive or negative for meshwork pattern were calculated by the Kaplan-Meier method. The incidence of HCC was significantly higher in the group positive for meshwork pattern (average incidence per year: 4.4%) than in the group negative for it (average incidence per year: 0.5%) (P<0.0001, Mantel-Cox test). On regression analysis with Cox's proportional hazards model, sex, alpha-fetoprotein and meshwork pattern were selected as independent risk factors for HCC. In conclusion, meshwork pattern appears to be an ultrasonographic sign useful for detecting a latent risk factor for HCC in patients with HBV-related chronic hepatitis and cirrhosis.