BOSTON -- A new French medical study supports growing evidence that a type of hepatitis virus may help cause liver cancer -- the top cancer killer worldwide.
All 20 alcoholics suffering liver cancer in the study also had hepatitis DNA in their liver cells, the French team reported in today's New England Journal of Medicine.
Viral hepatitis can cause a flu-like illness leading to liver failure. An estimated 200,000 people contract hepatitis B each year. Researchers recently developed a vaccine against the virus.
The 20 French patients were carriers of hepatitis B -- meaning they were infected with the virus over long periods of time, but didn't suffer symptoms of hepatitis disease.
Only eight of the 51 cancer-free alcoholics in the study showed evidence of hepatitis infection, the French team wrote.
The study was conducted by a genetics unit of the Institut National de la Sante et de la Recherche Medicale and Centre National de la Recherche Scientifique, two national science agencies with headquarters in Paris.
The link had previously been established by other researchers, including Dr. David Shafritz of Albert Einstein Medical School in New York.
Cancer of the liver is relatively unusual in the United States, causing three per 100,000 deaths a year -- but is on the increase. In the Mediterranean, the Middle East, southeast Asia, Africa, China and Japan, it causes 25 to 100 per 100,000 deaths annually.
Pollution, certain toxins and drugs, alcohol-induced cirrhosis (another liver disease) and some diet deficiencies have also been implicated.
Shafritz found hepatitis carriers are 22 times more likely to contract liver cancer.
Evidence of hepatitis has been found in up to 35 percent of liver cancer patients in the United States, Shafritz said.
