HPV is sneaky. Sexually transmitted, the human papillomavirus typically causes no symptoms but can set the stage for cancer to manifest some 20 or 30 years after it’s contracted.
Scientists have known since the 1990s that virtually all cases of cervical cancer can be linked to HPV infections. Now, an increasing number of other cancers are occurring in both men and women that may be due to HPV infection.
For both men and women, these include mouth, throat and anal cancers. Women also face risk of cancer of vulva; men, penile cancer.
“Over the last 20 years or so, we’ve seen what’s been characterized as an epidemic of tongue base and tonsil cancers in younger people without the typical risk factors,” says Dr. Tjoson Tjoa, a UCI Health specialist in head and neck surgical oncology and microvascular reconstruction. “It turns out it’s because of an aggressive strain of the HPV virus.”
Three vaccines to prevent infection
The Food and Drug Administration has approved three vaccines to prevent HPV infection. All are given to children and young adults, ages 10 to 26, through a series of two or three injections over a period of six to 12 months.
HPV vaccines stimulate the body to produce antibodies that prevent the virus from infecting cells. So far in tests of tens of thousands of people, no serious side effects have been demonstrated.
To be effective, vaccination should ideally begin between ages 10 and 14 when the immune response peaks and before exposure to the virus.
Unfortunately in California, the majority of children have not received the complete HPV vaccination series of two doses for children under 14 and three doses for those aged 15 to 26. A single dose provides only limited protection.
Vaccination rates are especially low among boys.
Vaccination low among boys
Here in California, the 2015 data for boys is:
- First vaccine = 58.5 percent
- Second vaccine = 41.8 percent
- Third vaccine = 29.5 percent
Some parents resist all vaccinations because of a feared connection between vaccination and autism — a theory that has been convincingly debunked, says Dr. William Armstrong, chair of the Department of Otolaryngology — Head and Neck Surgery.
“There’s also controversy because you’re vaccinating children for a sexually transmitted infection,” says Tjoa, “But it’s an entirely preventable cancer.”
When to vaccinate
HPV vaccination isn’t about sex education, and there’s no evidence that it opens the door to sexual experimentation. Doctors suggest an easy time to begin vaccinating children for HPV is when they get their Tdap (tetanus, pertussis, whooping cough) vaccination, which is often required for seventh-grade students. Insurance frequently covers the cost.
UCI Health offers vaccination and education through dozens of primary care sites throughout the region. HPV testing is also available in conjunction with Pap tests for cervical cancer. However, no tests are yet approved for detecting HPV in men.
Although research is continuing, there are currently no screening tests to detect cell changes caused by HPV infection in anal, vulvar, vaginal, penile, or oropharyngeal (throat) tissues.
Research is also underway into understanding which patients with HPV-related cancers might do better with a less intense treatment than the standard treatments of surgery, radiation and chemotherapy. There’s evidence these cancers related to HPV act differently from cancers linked to other causes, and Armstrong says the prognosis overall is better for this group of patients.
“Right now, we don’t have the answers. We need to determine which patients can have less intense treatment for their HPV-related head and neck cancers,” Armstrong says. “We’ll know more in a couple of years, when the results of ongoing studies become available.”