Widespread Hepatitis B Vaccination Has Dramatically Reduced Rate of Liver Cancer among Children and Young Adults in Taiwan  |
Hepatitis B is a major cause of hepatocellular carcinoma -- a type of primary liver cancer -- especially in areas where chronic HBV infection is endemic, as it is in much of Asia.
Mei-Hwei Chang and colleagues with the Taiwan Hepatoma Study Group aimed to investigate whether HCC prevention following the launch of the Taiwanese universal newborn HBV vaccine program in July 1984 has extended beyond childhood, as well as to identify predictors of HCC in vaccinated birth cohorts.
The investigators used 2 national HCC registries to collect data on 1958 patients who were aged 6 to 29 years when they were diagnosed with liver cancer between 1983 and 2004. The researchers analyzed age- and sex-specific HCC incidence among vaccinated and unvaccinated birth cohorts using Poisson regression models.
In addition, records from 64 patients who developed HCC despite vaccination and 5,524,435 vaccinated individuals without HCC born after initiation of the universal program were compared for HBV immunization characteristics during infancy and prenatal maternal hepatitis B surface antigen (HBsAg) and hepatitis B "e" antigen (HBeAg) status.
Results
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HCC incidence was significantly lower among children and adolescents aged 6-19 years in vaccinated birth cohorts compared with unvaccinated cohorts. |
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There were 64 cases of HCC among vaccinated patients (37,709,304 person-years) versus 444 cases among unvaccinated individuals (78,496,406 person-years). |
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The age- and sex-adjusted relative risk of developing HCC was 0.31, or about one-third, for individuals vaccinated at birth (P < 0.001). |
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Among vaccinated cohorts, the risk of developing HCC was significantly associated with the following factors: |
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Incomplete HBV vaccination (receiving fewer than 3 doses of vaccine): odds ratio [OR] 4.32; |
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Prenatal maternal HBsAg seropositivity: OR 29.50; |
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Penatal maternal HBeAg seropositivity with administration of hepatitis B immunoglobulin (HBIG) at birth: OR 5.13; |
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Penatal maternal HBeAg seropositivity without HBIG administration at birth: OR 9.43. |
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Based on these findings, the study authors concluded, "The prevention of hepatocellular carcinoma by this HBV vaccine extends from childhood to early adulthood."
"Failure to prevent hepatocellular carcinoma results mostly from unsuccessful control of HBV infection by highly infectious mothers," they added.
College of Public Health, National Taiwan University, Taipei, Taiwan; Genomics Research Center, Academia Sinica, Taipei, Taiwan; Chang Gung Memorial Hospital-Kaohsiung Medical Center, College of Medicine, Chang Gung University, Kaohsiung, Taiwan; Liver Research Unit, Chang Gung University and Hospital, Linkou, Taiwan; Tri-Service General Hospital, Taipei, Taiwan; Taipei Veterans General Hospital, Taipei, Taiwan; Taichung Veterans General Hospital, Taichung, Taiwan; Center for Disease Control, Taipei, Taiwan.
9/29/09
Reference
MH Chang, SL You, CJ Chen, and others (Taiwan Hepatoma Study Group). Decreased Incidence of Hepatocellular Carcinoma in Hepatitis B Vaccinees: A 20-Year Follow-up Study. Journal of the National Cancer Institute. September 16, 2009 (Epub ahead of print). (Abstract).
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