Hepatitis B vaccination and hepatocellular carcinoma rates in boys and girls

Context Hepatocellular carcinoma (HCC) has a male predominance and is close ly related to hepatitis B Virus (HBV) infection. Hepatitis B virus vaccinat ion was launched in 1984 in Taiwan for neonates of mothers carrying hepatit is B e antigen, resulting in a decreased incidence of HCC in children, The effect on boys vs girls is not known. Objective To evaluate the association between a HBV vaccination program wit h incidence of childhood HCC by sex. Design and Setting Analysis of data collected from Taiwan's National Cancer Registry System and the Taiwan Childhood Hepatoma Study Group between 1981 and 1996. Participants Children aged 6 to 14 years who were diagnosed as having HCC ( 201 boys and 70 girls). Main Outcome Measure Incidence of HCC in boys and girls before and after im plementation of the vaccination program. Results The boy-girl incidence ratio decreased steadily from 4.5 in 1981-19 84 (before the program's introduction) to 1.9 in 1990-1996 (6-12 years afte r the vaccination program was launched). The incidence of HCC in boys born after 1984 was significantly reduced in comparison with those born before 1 978 (relative risk [RR], 0.72; P=.002). No significant decrease in HCC inci dence was observed in girls born in the same periods (RR, 0.77; P=.20). The incidence of HCC in boys remained stable with increasing age, while an inc rease of HCC incidence with age in girls was observed. These age and sex ef fects remained the same regardless of birth before or after the vaccination program. Conclusion Our results suggest that boys may benefit more from HBV Vaccinat ion than girls in the prevention of HCC.