A new study suggests a link between hepatitis B virus (HBV) infection and an increased risk of extrahepatic bile duct cancer.
Located outside the liver, the extrahepatic bile duct collects bile from the liver and joins with a duct from the gallbladder to form the common bile duct. This then carries bile to the small intestine. Though rare, extrahepatic bile duct cancers are very hard to treat.
The current population-based study was conducted in Shanghai by Dr. Ann W. Hsing of the Maryland-based National Cancer Institute and colleagues. The team looked for HBV and hepatitis C virus (HCV) in three groups of patients: 417 with biliary tract cancers, 517 with biliary stones, and a comparison group of 762 randomly selected healthy persons.
HBV was detected in 7.3 percent of the population controls and in 14.2 percent of the subjects with extrahepatic bile duct cancer. HBV infection resulted in a 2.4-fold increase in cancer risk, the authors found. However, no significant association was noted between HBV and gallbladder cancer, gallbladder stones or bile duct stones.
The low prevalence of HCV found in the study population, 2 percent, limited the team's ability to estimate the association between this infection and biliary disease.
"In Shanghai, an HBV endemic area, chronic HBV infection was associated with a 2.4-fold risk of extrahepatic bile duct cancer," the authors concluded. "These results should be confirmed in other populations with varying risks of HBV and HCV infection."
The full report, "Hepatitis B and C Virus Infection and the Risk of Biliary Tract Cancer: A Population-Based Study in China," was published in the International Journal of Cancer (2008;122(8):1849-1853).
04/16/08
CHINA: Hepatitis B Tied to Bile Duct Cancer Outside Liver
Source: Reuters; Courtesy of the CDC National Center for HIV, STD, and TB Prevention