A U.S. scientist says cancer -- known to be caused by genetic cell mutations -- can also be caused by infections from viruses, bacteria and parasites.
"I believe that, conservatively, 15 to 20 percent of all cancer is caused by infections; however, the number could be larger -- maybe double," said Dr. Andrew Dannenberg, director of the Cancer Center at New York-Presbyterian Hospital/Weill Cornell Medical Center.
"Unfortunately, the public as well as many healthcare workers are unaware of the significance of chronic infection as a potentially preventable cause of cancer," he added.
Dannennberg made the remarks in a speech prepared for delivery Wednesday in Philadelphia during the annual international conference of the American Association for Cancer Research.
Copyright 2007 by United Press International
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