Virus Linked to Throat Cancer Trend
Oral Sex Considered a Risk Factor
Aug. 27, 2007 -- Unlike most head and neck cancers, throat cancer rates in the
United States have not dropped in recent years, and infection with the sexually
transmitted infection human papilloma virus (HPV) may be the cause.
HPV is a virus that causes genital warts and most cervical cancers, but its
transmission through oral sex has only recently been identified as a potential
cause of throat cancer.
In a newly published analysis of head and neck cancer rates in the U.S.,
researchers from Houston’s M.D. Anderson Cancer Center found the incidence of
throat cancer to be stagnant and even rising in some populations, defying a
downward trend in other head and neck cancers linked more closely with smoking.
The findings underscore the importance of research aimed at determining if
the newly available HPV vaccine is effective in
males, researcher Erich Sturgis, MD, MPH, tells WebMD.
“The vaccine has been shown to be almost 100% effective for preventing
cervical infection,” he says. “We would encourage the medical community and
[vaccine] industry to study its role in preventing this oral cancer.”
Throat Cancer Risk Factors
Tobacco use and drinking alcohol are by far the biggest risk factors for
head and neck cancers. About 90% of patients with these malignancies either
smoke or chew tobacco, or have done so in the past, and up to 80% of oral
cancer patients also drink a lot of alcohol, according to the American Cancer
In their newly published analysis of head and neck cancer trends in the
U.S., Sturgis and co-author Paul M. Cinciripini, MD, showed that the decline in
smoking has led to a decline in most head and neck cancers over the past two
“These decreasing incidence rates trail by 10 to 15 years the declines in
smoking prevalence, which began in the 1970s,” they wrote in the Oct. 1 issue
of the journal Cancer.
The main exception to this trend has been throat cancer, more specifically
defined as cancer of the oropharynx, which includes the tonsils, base of the
tongue and soft palate, and side and back of the throat.
These cancers are rare, accounting for just 10,000 of the roughly 45,000
head and neck malignancies diagnosed each year in the U.S. But their incidence
has remained steady, overall, Sturgis and Cinciripini write, and tongue cancer
rates among young adults have increased.
They conclude that this is likely due to HPV infection, spread through oral
Sturgis tells WebMD that over the last five years, 35% of the throat cancer
patients treated at M.D. Anderson Cancer Center had no history of smoking and
that close to 90% of patients who had never smoked showed evidence of oral
infection with HPV.