A
new study has shown that evidence of past hepatitis B infection was
twice as common in people with pancreatic cancer than in healthy
controls. This study is the first to report an association between past
exposure to the hepatitis B virus and pancreatic cancer, but
researchers cautioned that more studies are necessary to evaluate the
nature of the link.
"While our findings indicate that past
exposure to hepatitis B is associated with the development of
pancreatic cancer, more research is needed to determine whether this
relationship is one of cause and effect," said lead author Manal M.
Hassan, MD, PhD, assistant professor at The University of Texas M. D.
Anderson Cancer Center. "If these findings can be confirmed by other
studies, hepatitis B could be another risk factor for pancreatic cancer
that is readily modifiable with treatment, and even preventable with a
vaccine."
In this study, Dr. Hassan and her colleagues compared
evidence of hepatitis B and C infection (as determined by blood tests
assessing antibodies to these viruses) between 476 patients with
pancreatic cancer and 879 matched healthy individuals. Evidence of past
exposure to hepatitis B was found in 7.6 percent of patients with
pancreatic cancer versus 3.2 percent of controls. The association
between hepatitis B exposure and pancreatic cancer remained
statistically significant even after controlling for other risk
factors, such as smoking. People with both diabetes (an established
risk factor for pancreatic cancer) and hepatitis B exposure had a
7-fold increase in pancreatic cancer risk, compared to controls. No
association was observed between hepatitis C exposure and pancreatic
cancer.
The authors noted that past studies have reported the
presence of hepatitis B antigens in pancreatic fluids; others have
identified impaired pancreatic function in people with chronic
hepatitis B infection. These findings suggest that the hepatitis B
virus may cause inflammation or DNA damage in the pancreas, which could
increase cancer risk.
The researchers also indicated that there
may be an increased risk of liver failure after chemotherapy treatment
among patients with pancreatic cancer who have a history of hepatitis B
infection. Dr. Hassan noted that if their findings are confirmed,
oncologists may want to consider checking the hepatitis B status of
their patients with pancreatic cancer before beginning chemotherapy.