• 6/6/2006
  • Atlanta, GA
  • Kawanza Newson
  • TheState.com

A vaccine against cervical cancer also prevents other types of gynecological cancers and could lower the incidence of tumors in the head and neck, too, according to a new study released Sunday.

“If we vaccinate everybody in the U.S., we could probably impact head and neck cancer in approximately 20 years,” said Marshall R. Posner, an associate professor at Harvard Medical School and medical director of the head and neck oncology program at Dana-Farber Cancer Institute in Boston.

On Sunday, researchers at a cancer meeting in Atlanta released data showing that Gardasil, manufactured by Merck & Co., was 100 percent effective in preventing vaginal and vulvar cancers associated with the human papillomavirus, or HPV, in more than 18,000 women and adolescents from the United States, South America and Asia.

For the study, researchers gave females ages 15-26 up to three doses of the vaccine over a six-month period and followed them for two years. None of the women who received the vaccination developed HPV-related vaginal or vulvar precancers, compared to 24 women in the control group.

“In human disease, there has never been a vaccine this effective,” said Jorma Paavonen, the professor and chief in the department of obstetrics and gynecology at the University of Helsinki in Finland who presented the study.

“It’s going to make a major impact and we certainly hope, in the future, this vaccine will be part of the national vaccine program, not only in the U.S., but elsewhere in the world,” he said.

HPV causes cervical cancer and genital warts and is also linked to penile and anal cancer. The virus is the most common sexually transmitted disease, and the American Cancer Society estimates that HPV affects more than 50 percent of sexually active adults.

The virus, however, has also been found in cancers of the tongue, tonsils and pharynx, said Stuart Wong, an assistant professor of medicine at the Medical College of Wisconsin who practices at Froedtert Memorial Lutheran Hospital.

Last month, a U.S. Food and Drug Administration advisory committee recommended approval of Gardasil. The FDA is not required to follow the recommendations of its outside panels of experts but usually does. An agency decision is expected as early as Monday.

Gardasil protects against the two types of HPV, 16 and 18, believed responsible for about 70 percent of cervical cancer cases. It also protects against two other virus types, 6 and 11, that cause 90 percent of genital wart cases. All four virus types are sexually transmitted.

The vaccine, however, needs to be given before a person has sexual contact because it’s not going to work optimally if people have already been exposed to the virus, said Erik Wait, an obstetrician and gynecologist with the University of Wisconsin Medical School in Madison and Meriter Hospital.

“We’ll have a huge hill to climb to convince parents to vaccinate their 12- or 13-year-old boys or girls,” said Vanessa Barnabei, professor of obstetrics and gynecology at the Medical College of Wisconsin and Froedtert.

“But even if we treat the most common virus, there may be other viruses that can become common, so that means that you’ll eventually have to create more vaccines,” Wait said.

An international study also released at the meeting Sunday found that giving chemotherapy that includes the drug docetaxel to patients prior to chemo-radiation reduces their likelihood of death by 30 percent in head and neck cancer patients.

Such a sequential treatment plan is not readily accepted by some head and neck cancer specialists, however, Wong said.

“While this data is very intriguing and is quite good, we won’t know the best way to treat patients until we have studies that compare sequential therapy vs. chemotherapy alone,” he said.

Wong is among a group of researchers who have launched a national head and neck cancer registry to gather detailed data for analysis of all treatments.

Tumors in the head and neck region often are difficult to treat.

Radiation therapy has become the preferred treatment method. It’s commonly believed that a patient can have one round of radiation therapy per lifetime, though there’s increasing evidence that repeat radiation with chemotherapy may be beneficial.

In this study, Posner and colleagues showed that overall survival among patients receiving the chemotherapy before a combination of chemotherapy and radiation was 62 percent compared to 48 percent in the control group.