Science News Archive

Liver cancer gene link

There are some interesting new results out this week about the link between Hepatitis B infection and cancer, published in the Journal of the National Cancer Institute. Hepatitis B infection is relatively rare in the West, but it's a big problem in sub-Saharan Africa and Asia.

And the bad thing about Hep B infection is that it increases the risk of the most common type of liver cancer called hepatocellular carcinoma. Again, this type of cancer is relatively rare in the West, but it's actually the fifth most common cancer worldwide, and the third most common cause of cancer death. More than eight out of ten cases are in East Asia or sub-Saharan Africa, and most of these are linked to the Hepatitis B infection.

It’s a bit of a mystery as to why some people are more susceptible to developing liver cancer when they're infected with hep B than others. And now a new analysis from Guangwen Cao and his team in Shanghai has shed some light on this mystery.

The researchers did something known as a meta-analysis, looking at over 40 studies that included more than 11,500 people infected with Hepatitis B, 2,801 of whom had liver cancer. They were looking at whether mutations in the virus DNA could affect the chances of the carrier developing cancer or not. There have been some previous  studies looking at this, but they've been small, and the results haven't been conclusive.

But by collecting together the results from many studies, Cao and his team were able to discover that four certain mutations in Hep B were linked to the development of liver cancer, and were also more likely to crop up in the virus as hepatitis infection progressed from an infection without any symptoms to liver cirrhosis, and then on to cancer.

The researchers suggest that patients with chronic hepatitis B infection should be regularly screened for mutations in the virus, which might help doctors identify those who are likely to go on to get cancer. They can then be offered more aggressive anti-viral treatment

At the moment, there is some debate as to how strongly people should be treated with anti-viral drugs, due to the risks of developing drug resistance, as well as side effects, along with the cost of the drugs. So being able to identify those patients who are at most risk of developing liver cancer, and treating them first, could be a real help.

You can also listen to our special World Hepatitis Day Podcast...

5th Jul 2009