Vaccine could prevent most cervical cancers

A vaccine based on the seven types of human papillomavirus (HPV) most commonly linked to cervical cancer could prevent most cases of the deadly disease, researchers predict.

As yet, however, no such vaccine exists.

"HPV vaccines offer today the best strategy to combat cervical cancer," Dr. Nubia Muñoz from International Agency for Research on Cancer, Lyon, France told AMN Health.

Muñoz and colleagues conducted an analysis of all HPV types in cervical cancer from an international survey and from a multicenter study, involving more than 3600 women with cervical cancer from 25 countries.

Overall, about 93 percent of cervical cancers contained some type of HPV. The percentage varied slightly based on cancer type and geographic location.

At all sites around the world, two types of HPV were most commonly linked to cervical cancer - types 16 and 18. Seven HPV types - 16, 18, 45, 31, 33, 52, and 58 - accounted for 87 percent of all cervical cancer cases worldwide, with little regional variation, the researchers note.

"Generating a vaccine with seven HPV types would be technically feasible," the investigators state. "However, the production cost may be high, and the protection conferred by the less common HPV types may be difficult to demonstrate clearly."

"Considering that cost might be most limiting to developing countries, a vaccine containing the two (HPV 16 and 18) or three (HPV 16, 18, and 45) most common types, which could be less expensive, might be more realistic," Muñoz said.

"Vaccinating against HPV 16 and 18 while waiting for vaccines containing more types makes a lot of sense, because 70 percent of cervical cancers could be prevented," Muñoz concluded. "This is much more than the prevention achieved by badly conducted screening programs which are currently implemented in some developing countries."

SOURCE: International Journal of Cancer, August 20, 2004.