People who have had more than five oral-sex partners in their lifetime are 250% more likely to have throat cancer than those who do not have oral sex, a new study suggests. The researchers believe this is because oral sex may transmit human papillomavirus (HPV), the virus implicated in the majority of cervical cancers. One way to avoid this is to use condoms during oral sex. Other experts say that the results provide more reason for men to receive the new HPV vaccine.
Merck & Co.'s Gardasil vaccine is approved for preteen girls to prevent cervical cancer caused by a sexually transmitted virus. Now researchers say boys should also be vaccinated, in order to help stop cancers linked to oral sex.
Bloomberg News writes, "A growing body of research shows that human papilloma virus, responsible for cervical cancer, is also linked to about half of certain throat, or oropharyngeal, cancers. In a research review in the journal Cancer, doctors from the University of Texas M.D. Anderson Cancer Center said scientists should step up studies of the HPV vaccine in boys to expand the vaccine's use."
Recent findings tie the virus to cancers of the penis, anus and vagina, as well as head and neck cancers, which mostly affect males. This points to a need to vaccinate boys before they are sexually active, the researchers said.
Merck is studying the vaccine in boys and plans to seek U.S. approval for that use, said spokeswoman Kelly Dougherty.
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Full story from Bloomberg News:
Aug. 27 (Bloomberg) -- Merck & Co.'s Gardasil vaccine, approved for preteen girls to prevent cervical cancer caused by a sexually transmitted virus, should also be given to teenage boys to help avert cancers linked to oral sex, researchers said.
A growing body of research shows that human papilloma virus, responsible for cervical cancer, is also linked to about half of certain throat, or oropharyngeal, cancers. In a research review in the journal Cancer, doctors from the University of Texas M.D. Anderson Cancer Center said scientists should step up studies of the HPV vaccine in boys to expand the vaccine's use.
Gardasil may generate more than $3 billion in annual sales for Whitehouse Station, New Jersey-based Merck, analysts say. The best way to reduce cancer-causing HPV is to widen the pool of children vaccinated with Gardasil, the researchers say. Merck is studying the shot in boys and plans to seek U.S. approval for that use, said spokeswoman Kelly Dougherty.
``We would encourage industry and scientists to study the efficacy in boys and men so the vaccination program can be expanded,'' said Erich Sturgis, associate professor of head and neck surgery at M.D. Anderson and the report's lead author, in an interview. ``We know men are getting exposed and we know a major proportion of oropharyngeal cancers are caused by HPV.''
Recent findings also tie the virus to cancers of the penis, anus and vagina. The link to head and neck cancers, which mostly affect males, points to a need to vaccinate boys before they are sexually active, the researchers said.
Result Next Year
Merck expects to have data on use of the vaccine in teenage boys next year, Dougherty said. The Merck vaccine can already be used in boys in the European Union, Mexico, Australia, New Zealand, Indonesia, Costa Rica and Korea.
Merck's shares fell 70 cents, or 1.4 percent, to $50.12, in New York Stock Exchange composite trading. The stock has increased 15 percent this year.
GlaxoSmithKline Plc, which is seeking U.S. and European approval of a similar vaccine called Cervarix, said it's focusing the product on girls and women.
Head and neck cancers, closely linked to smoking, have declined as the number of people who use tobacco dropped. However, oropharyngeal cancers, including the tonsils and back part of the tongue, are rising, especially among younger adults, studies show.
``Changing sexual practices such as more frequent oral sex in adolescents and young adults could contribute to an increase in oncogenic HPV-associated oropharyngeal cancers,'' researchers said in the report.
Tonsil, Tongue Increases
Tonsil cancers have increased 4 percent and tongue cancers 2 percent a year in the past 30 years among adults younger than 45, according to studies cited in the review. Many of the cancers were among non-smokers, which points to HPV as the culprit behind the rise in the cancers, M.D. Anderson researchers said.
``This was once a disease exclusively of smokers and drinkers,'' Sturgis said. ``Our experience is between a third to a half of oropharyngeal cancer patients have never smoked.''
More than 90 percent of HPV-positive throat cancer tumors show infection with the HPV-16 form of the virus. Merck's and Glaxo's vaccines target strains HPV 16 and HPV 18. Merck's Gardasil also targets two additional HPV strains that cause genital warts.
Approved in June 2006, Gardasil generated $723 million in sales during the first half of this year.
Head and neck cancers are the latest malignancies tied to HPV infection generating attention from health experts that would like to see broader use of the Merck vaccine.
Every year, about 650,000 people worldwide are diagnosed with head and neck cancers, and 350,000 die from the diseases, according to the American Cancer Society, based in Atlanta.
``This is an emerging area,'' said Joseph Bocchini, chairman of pediatrics at Louisiana State Health Sciences Center in Shreveport, in an interview. ``As the data evolves, it would add the possibility of not only genital cancer control but oropharyngeal cancer control as well.''
Bocchini who heads the American Academy of Pediatrics committee on infectious diseases, which makes recommendations on childhood vaccines, said it's too early to say whether boys should be vaccinated until more data is available.
``At this point there is nothing to suggest it would act differently,'' he said. ``There is a very good chance it will be as effective in boys as girls and women.''
Cancer is the medical journal of the American Cancer Society.
To contact the reporter on this story: Angela Zimm in Boston