Experts Debate Giving HPV Vaccine to Boys
Spread of the virus linked to cervical cancer can harm them, too
FRIDAY, May 18, 2007 (HealthDay News) -- Amid the controversy around mandated vaccination of young girls against the human papillomavirus (HPV), some experts are beginning to wonder whether the shot should also be given to boys.
While males cannot get HPV-linked cervical cancer, they make up half of the equation when it comes to spreading the sexually transmitted virus. And a new study released last week shows that the virus is also a leading cause of throat cancer, which affects both sexes.
"This is a viral infectious process, and the majority of the time it is passed through heterosexual contact. And I think it's important to consider boys as equal players in that process," said Dr. Michael Bookman, director of medical gynecologic oncology at Fox Chase Cancer Center in Philadelphia.
"Boys are not as prone to [HPV-linked] cancer as girls, but they are obviously involved in the transmission, and there is some risk of cancer in boys, as well," he added.
No one is debating the effectiveness of the vaccine, called Gardasil. The shot is targeted against the four strains (out of 15) of HPV that are thought to trigger 70 percent of cervical cancers.
Since its approval for use in girls and women between the ages of 9 and 26 by the U.S. Food and Drug Administration last June, several states have moved to mandate Gardasil's inclusion into routine school vaccination programs. That's because vaccinating before the onset of sexual activity is most effective in preventing HPV infection.
Those efforts have met with strong opposition, however. Some conservative groups worry the vaccine will encourage sex among young people, while other critics view the mandates as an intrusion on parental rights. Most state measures do give parents the right to opt out of the program, however.
So far, those debates have centered on young girls. But, in more rare instances, boys and men can fall prey to HPV as well. Reporting last week in the New England Journal of Medicine, a team of researchers at Johns Hopkins University confirmed that infection with HPV via oral sex is by far the leading cause of throat cancer, which strikes 11,000 American men and women each year. HPV is also a major cause of anal cancer and genital warts, both of which affect either sex.
The threat of throat cancer is especially troubling, Bookman said, because doctors traditionally only look for these malignancies in long-time smokers and drinkers. "Head and neck exams are more associated with smoking and alcohol and less associated with HPV, although that's changing," he said.
And while girls and women typically see a gynecologist for their Pap smear to look for cervical cancer, "how many boys and men are going to go to a doctor and ask them to look at their throat? It's just not that common," Bookman said.
Debbie Saslow is director of breast and gynecological cancers at the American Cancer Society. She agreed that HPV also poses a threat to males, but she's not yet convinced that Gardasil would help protect them.
"We have been considering vaccination for boys since day one, but the problem is that there is just no data yet -- everything is holding until we get data that the vaccine actually works in boys," she said.
Gardasil's maker, Merck & Co., is largely responsible for pulling that data together. However, according to Bookman, "they took a more conservative stance when they approached the FDA for licensure, registration and vaccine recommendations -- their safety data base was stronger for girls than boys."
Saslow also is doubtful whether Gardasil -- which costs $360 per three-shot regimen -- would prove to be cost-effective if provided to boys as well, at least in terms of preventing the biggest threat, cervical cancer.
"It may be cost-effective to vaccinate boys if not that many girls get vaccinated," she said. "But if most of the female population ends up getting vaccinated, then vaccinating boys won't add very much."
But what about the vaccine's cost-effectiveness in preventing anal and throat cancers, plus genital warts, among boys? Saslow said that since Gardasil has not yet been proven to be effective in boys, or to be effective against cancers outside the cervix, those points remain up in the air. "We still have all these questions that we need to look at," she said.
Another expert, Dr. Robert Frenck, a professor of pediatrics at Cincinnati Children's Hospital, was equally noncommittal. Frenck, who sits on the American Academy of Pediatrics' committee on infectious diseases, said his group is "in the process of developing the recommendations for HPV vaccine use." He said the AAP recommendations would focus only on the vaccine's "currently [FDA] licensed usage," which is exclusively for females.
Still, Bookman believes that, should Gardasil prove effective in boys, widening its use to both sexes "is the correct way to try and do things."
"What about everything that we know about controlling any other type of infectious process? Where we wouldn't discriminate on the basis of sex, we would vaccinate universally," he said. "Yes, in women cervical cancer is a more serious risk statistically than other cancers in men. But I think that the best way of controlling it with a vaccine is to use it broadly."
Learn more about HPV and cervical cancer at the U.S. Centers for Disease Control and Prevention.