Hepatitis B May Up Pancreatic Cancer Risk

CancerWise - December 2008 (MD Anderson)

Exposure to the hepatitis B virus (HBV) may increase the risk of pancreatic cancer. Also, chemotherapy for pancreatic cancer may reactivate dormant HBV.

Researchers at M. D. Anderson published these findings, the first of their kind, in the Oct. 1 edition of the Journal of Clinical Oncology.

Significance of results

Pancreatic cancer is diagnosed in 37,000 people in the United States each year, and more than 34,000 people die of the disease annually, according to the American Cancer Society. It often is diagnosed in the late stages, and few risk factors are known.

"If this study is validated, it will give us more information about the risk factors for pancreatic cancer and possibly even help prevent it in some cases," says lead author Manal Hassan, M.D., Ph.D., assistant professor in M. D. Anderson's Department of Gastrointestinal Medical Oncology.
HBV and hepatitis C virus (HCV) are major global health problems, affecting about 2% of the population worldwide.

Background

The word "hepatitis" means "inflammation of the liver." Previous research has shown HBV and HCV are major causes of liver cancer, but little is known about their roles in other cancers.
However, the liver is close to the pancreas, and the two organs share blood vessels and ducts. This makes the pancreas a potential target for hepatitis viruses.
Other research has indicated chronic HBV infection may impair pancreatic function and that HBV may grow in the pancreas.

Research methods

This study, which began in 2000, included:

• 476 M. D. Anderson patients with early pancreatic cancer
• 879 people without pancreatic cancer

Healthy participants were matched with patients by age, gender and race.
Researchers tested the blood of all participants for HCV and HBV antibodies, which indicate past exposure to HCV and HBV.

Primary results

The percentage of people who had past exposure to HBV were:

• 7.6% of pancreatic cancer patients
• 3.2% of people without pancreatic cancer

Exposure to HCV was not significantly different in the two groups.

Additional results

The study confirmed previously reported risk factors for pancreatic cancer: cigarette smoking, diabetes and a family history of the disease.

People exposed to HBV may develop occult (hidden) HBV infection. In these cases, the M. D. Anderson researchers say, there is a potential for reactivation of HBV during chemotherapy, the most common treatment for pancreatic cancer.

What’s next?

Hassan stresses that these early results need further study. The researchers plan to work with other institutions to compare results among other groups. They also want to study people who are actually infected with the virus.

If they are confirmed, these results may offer new insight into pancreatic cancer, possibly preventing some cases in the future.