title: Hepatitis B vaccination and hepatocellular carcinoma rates in boys and girls.
abstract: BACKGROUND
  Hepatocellular carcinoma (HCC) has a male predominance and is closely related to hepatitis B virus (HBV) infection. Hepatitis B virus vaccination was launched in 1984 in Taiwan for neonates of mothers carrying hepatitis 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 with incidence of childhood HCC by sex.
  
  
  METHODS
  Analysis of data collected from Taiwan's National Cancer Registry System and the Taiwan Childhood Hepatoma Study Group between 1981 and 1996.
  
  
  METHODS
  Children aged 6 to 14 years who were diagnosed as having HCC (201 boys and 70 girls).
  
  
  METHODS
  Incidence of HCC in boys and girls before and after implementation of the vaccination program.
  
  
  RESULTS
  The boy-girl incidence ratio decreased steadily from 4.5 in 1981-1984 (before the program's introduction) to 1.9 in 1990-1996 (6-12 years after the vaccination program was launched). The incidence of HCC in boys born after 1984 was significantly reduced in comparison with those born before 1978 (relative risk [RR], 0.72; P =.002). No significant decrease in HCC incidence 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 increase of HCC incidence with age in girls was observed. These age and sex effects remained the same regardless of birth before or after the vaccination program.
  
  
  CONCLUSIONS
  Our results suggest that boys may benefit more from HBV vaccination than girls in the prevention of HCC.
authors: Department of Pediatrics, National Taiwan University Hospital, No. 7, Chung-Shan S. Road, Taipei, Taiwan, Republic of China. mhchang@ha.mc.ntu.edu.tw
authors: M H
authors: MH
authors: Chang
authors: W Y
authors: WY
authors: Shau
authors: C J
authors: CJ
authors: Chen
authors: T C
authors: TC
authors: Wu
authors: M S
authors: MS
authors: Kong
authors: D C
authors: DC
authors: Liang
authors: H M
authors: HM
authors: Hsu
authors: H L
authors: HL
authors: Chen
authors: H Y
authors: HY
authors: Hsu
authors: D S
authors: DS
authors: Chen
mesh_terms: D000293:Adolescent; D006528:Carcinoma, Hepatocellular / Q000453:epidemiology* / Q000821:virology; D002648:Child; D005260:Female; D006509:Hepatitis B / Q000150:complications / Q000517:prevention & control; D017325:Hepatitis B Vaccines / Q000008:administration & dosage; D006801:Humans; D017589:Immunization Programs; D015994:Incidence; D007231:Infant, Newborn; D008113:Liver Neoplasms / Q000453:epidemiology* / Q000821:virology; D008297:Male; D015337:Multicenter Studies as Topic; D016012:Poisson Distribution; D012042:Registries; D012306:Risk; D017678:Sex Distribution; D013624:Taiwan / Q000453:epidemiology; D014611:Vaccination / Q000706:statistics & numerical data*
chemical_list: D017325:Hepatitis B Vaccines