Associated Press (10.04.11) - Wednesday, October 05, 2011
The incidence of HPV-positive oropharyngeal cancers has risen
over time, and these now account for the majority of such
cancers, according to new study.
The overall incidence of oropharyngeal cancers has risen 28
percent since 1988, to nearly 10,000 new cases annually, even
as other head and neck cancers have declined. Incidence among
women, who account for about one in four cases, is holding
steady, while it is rising among men, said study leader Dr.
Maura Gillison, a head-and-neck cancer specialist at Ohio
The new study directly tested tumor tissue from 271
oropharyngeal cancer patients whose samples were stored in
cancer registries in Hawaii, Iowa, and Los Angeles. The
proportion that was HPV-positive rose from 16 percent in the
late 1980s to nearly 73 percent by the early 2000s.
That would translate to incidence rates of HPV-positive tumors
more than tripling in the overall population, while HPV-
negative tumors dropped by half. The shift perhaps reflects
changes in smoking behaviors and increased oral sex and oral
HPV exposure over time, the study suggested.
The lower proportion of HPV-positive oral cancers among women
raises questions about gender differences in sexual behavior
and whether HPV lingers longer in men. However, it is not
clear whether oral sex is the only way HPV is being
transmitted, cautioned Dr. Gregory Masters of the American
Society for Clinical Oncology, who was not involved in the
The full report, "Human Papillomavirus and Rising
Oropharyngeal Cancer Incidence in the United States," was
published online ahead of the print edition of Journal of
Clinical Oncology (2011;doi:10.1200/JCO.2011.36.4596).