Cervical Cancer Vaccine Worth the Cost: Study

ByABC News
August 20, 2008, 10:37 PM

Aug. 21 -- WEDNESDAY, Aug. 20 (HealthDay News) -- Vaccinating all 12-year-old girls against the virus that causes cervical cancer, along with "catch-up" immunizations of women under the age of 21 and revised screening guidelines, would be cost-effective ways to combat the disease, a new study by Harvard researchers suggests.

But this conclusion, published in the Aug. 21 issue of the New England Journal of Medicine, is based on computer modeling rather than "real world" data, leading some experts, including the authors of a related editorial, to question the advisability of implementing widespread vaccination programs.

"For this generation of teenagers, we're not going to have data for the next 15 or 20 years on how effective it [a cervical cancer vaccine] is, what it changes about the dynamics of cervical cancer, how long the vaccine lasts, whether you can then extrapolate this to decreasing screening guidelines," said Dr. Jennifer Wu, an obstetrician/gynecologist at Lenox Hill Hospital in New York City. "We need more long-term data from this generation of girls getting vaccinates now [to] make decisions on a population basis."

The study data may also not be relevant to individual patients -- for example, a 28-year-old woman who has not yet become sexually active, Wu said.

Human papillomavirus (HPV) is a sexually transmitted virus that causes cervical cancer. Three-quarters of U.S. women will be exposed to HPV at some point in their lifetime and, at any one time, one-quarter have been infected.

Two strains of HPV -- HPV-16 and HPV-18 -- cause roughly 70 percent of cervical cancer cases worldwide. HPV also causes 90 percent of anal cancers, 40 percent of vulvar and vaginal cancers, and 3 percent of oral cancers.

The first vaccine against the virus, Gardasil, was approved in 2006. The U.S. Centers for Disease Control and Prevention currently recommends that 11- and 12-year-old girls be targeted for this vaccine, as most girls of this age are not yet sexually active, have not yet been exposed to HPV, and will therefore achieve maximum protection.