A recent study at Brown University has shown that alcohol and tobacco use doesn't further increase the risk of contracting head and neck cancers for people infected with human papilloma virus type 16 (HPV16), a common strain of the sexually-transmitted HPV.
The findings published in the Journal of the National Cancer Institute, provided strong evidence that these major cancers have two distinct causes and may represent two distinct classes of cancer which would require different prevention and treatment strategies.
According to National Institutes of Health, an estimated 20 million Americans are currently infected with genital HPV and 50 to 75 percent of sexually active men and women are infected with HPV at some point in their lives. Young women and girls receive the HPV vaccine to prevent cervical cancer.
The research led by Karl Kelsey, a Brown professor of community health and pathology and laboratory medicine and the director of the Center for Environmental Health and Technology also revealed that it has public health policy implications.
"Our current HPV vaccine recommendations should change," Kelsey said.
"Head and neck cancers, regardless of their cause, are predominantly male diseases. If boys and men received the HPV vaccine, a lot of these cancers could be prevented," he added.
"We should start testing this vaccine on men," he said.
The study was conducted over 485 head and neck cancer patients who were diagnosed at nine Boston-area hospitals between December 1999 and December 2003 and 549 cancer-free people based on age, sex and town of residence.
All the test subjects were asked about lifetime smoking and alcohol consumption and also gave a blood sample, which was screened for HPV16 antibodies. The team then conducted a statistical analysis to estimate the effects of the different risk factors.
The results showed that smoking and drinking didn't add to the risk of head and neck cancer for subjects exposed to HPV16.
We have a profound bit of evidence that HPV16-associated head and neck cancer is a very different disease," the professor said.
"Under a microscope, it looks like the same cancer you get from smoking and drinking. But how you get this form of the disease — and how you would prevent and treat it — is quite different," he further added.
The research was funded by National Cancer Institute.