A new study shows that giving men Gardasil is cost-effective and prevents throat cancer.
Controversy over the HPV vaccine has centered on its risks to girls and the idea that protecting them against cervical cancer could also lead them to experiment with sex at a younger age. But a new study underscores the effect of HPV on men, and points out that vaccinating men against the virus could prevent throat cancer as well.
About 9,300 men in the U.S. each year are affected by HPV-caused cancers, among them oropharyngeal cancer that occurs in the middle part of the throat behind the mouth and can develop around the tonsils and the back of the tongue. That number is expected to grow dramatically in the coming years.
“It is projected that by 2020, HPV-related oropharyngeal cancer will become the most common HPV-related cancer in the U.S., surpassing cervical cancer," Dr. Donna Graham, a medical oncologist who led a new study on vaccination in men, said in a statement.
The virus can be transmitted through oral sex, but the cases of throat cancer are four times more common in men than women. Men can also carry the virus in the genitals without knowing it, partly because researchers still have not figured out how to test men for the virus to detect early cancer cells. The new study in which Graham was involved shows that administering the vaccine to more boys could prevent them from getting cancer much later in life.
"People who are exposed to the virus may or may not get infected," says Dr. Lillian Sui, another author of the study who is also staff medical oncologist at Princess Margaret Cancer Centre and a professor at the University of Toronto.
The study, released online Monday in CANCER, a peer-reviewed journal of the American Cancer Society, indicates that vaccinating 12-year-old boys against HPV is a cost-effective strategy for preventing throat cancer.
Researchers applied a statistical model to 192,940 Canadian boys who were 12 years old in 2012, and found that vaccination could save $6 million to $22 million, depending on the cost of the vaccine, its effectiveness, the cost of cancer treatment and the survival rate of patients who get cancer.
Data from the U.S. Centers for Disease Control and Prevention show vaccination rates for males climbed from 20.8 percent in 2012 to 34.6 percent in 2013. Sui says that if more boys were vaccinated, then the vaccine would prevent throat cancer as effectively as it prevents cervical cancer.
For women, the vaccines Gardasil and Cervarix protect against 70 percent of cervical cancers and 90 percent of genital warts cases. They work in the body for at least a decade without becoming less effective and have not been associated with any long-term health problems. Gardasil is the vaccine typically given to men.
Still, rates of vaccination even for women are not as high as they are for other vaccines, and a November 2014 CDC report showed millions of U.S. women are not getting screened for cervical cancer. "Herd immunity," which occurs when large numbers of people become immune to a virus, requires 80-90 percent of people to be vaccinated in order to be effective. Vaccinating more men would help protect women who are not vaccinated as well as protecting men who have sex with unvaccinated men.
Concerns linger over what administering the vaccine could mean to young people, partially because it is recommended by the CDC at such a young age. For boys and girls, the agency has recommended since 2011 that children receive the three-part vaccine at ages 11 or 12. The agency has said that doing so would allow the immune system to build before teens become sexually active.
The most common sexually transmitted disease in the U.S., HPV infects 14 million people a year. It has more than 100 strains, most of which are not harmful and go away within two years. About 30 types, however, can put women at risk for cervical, vulvar or vaginal cancer. Other types cause warts in men and women. Even people who have no symptoms can spread the virus, and cancer can take years to develop after a person becomes infected.
The CDC says that not having sex is the only sure way to avoid HPV entirely – though condoms can reduce the likelihood of transmission.
Sui isn't a pediatrician, so she points out that she doesn't have conversations about the vaccine with young people – but she does see patients down the line who have developed cancer. The vaccines may seem irrelevant at such a young age but parents, doctors and young people should discuss it, she says.
For men, throat cancer develops anywhere from 40-60 years of age, and a test can determine whether HPV is the cause. Women can have Pap smears or HPV tests for early screening efforts, but these types of screening methods do not exist for men. Sui says the incidences of throat cancer found to be related to HPV range from 70-80 percent in North America.
Smoking also can increase the risk of developing HPV-related throat cancer, while the virus can also lead to cancers of the anus and penis. Men are likely to have a better outcome if cancer of the throat is found to be linked with HPV rather than with smoking, Sui says. They are likely to live longer, and this type is less likely to recur, according to the American Cancer Society.