Hepatitis B link to cancer is clarified
By Nathan Seppa
It’s well established that hepatitis B virus can cause liver cancer. Scientists in Taiwan now report that a certain kind of hepatitis B is much more likely than others to lead to cancer and that large amounts of any type of the virus correlate with high cancer risk.
The researchers obtained blood samples from 4,841 men diagnosed with hepatitis B but not yet treated for the condition. Over the next 14 years, 154 of the patients developed liver cancer. The researchers then compared blood from these men with that from 316 similar men in the study who hadn’t developed cancer. The comparison indicated that the men with cancer were five times as likely to have a kind of hepatitis B called genotype C.
There are seven genotypes of hepatitis B, which are forms of the virus whose DNA differ from each other, explains study coauthor Ming-Whei Yu, an epidemiologist at National Taiwan University in Taipei.
The blood samples revealed that high amounts of any hepatitis genotype increase the risk of liver cancer. In particular, men whose blood carried a high load of genotype C of hepatitis B virus faced a 27-fold higher risk of developing cancer, compared with men with a low load of one of the virus’ other genotypes, Yu and her colleagues report in the Feb. 16 Journal of the National Cancer Institute.
Screening hepatitis B patients for their virus genotype could reveal people at especially high risk of cancer, Yu says. Some medications can suppress the virus.