Oral sex has been linked to throat cancer in a new study by the New England Journal of Medicine [11May07]. Human papillomavirus (HPV), which can be transmitted during oral sex, is the main cause of oropharyngeal (throat) cancer, researchers found. The study is the first to prove the link.
Researchers compared 100 men and women who were recently diagnosed with oral cancer with 200 similar people without the disease. They found that participants who reported having oral sex — fellatio or cunnilingus — with six or more partners were at the highest risk (8.6 times more) of develping throat cancer. "It's the human papillomavirus that drives the cancer," Dr. Maura Gillison, the lead author of the study, told The Globe and Mail. "Health care providers need to know that these cancers can occur in people that don't smoke or drink."
Gillison [assist prof, oncology and epidemiology, Johns Hopkins University, Baltimore, MD] said the more oral-sex partners an individual has, the greater the risk is of getting oral cancer.
Researchers found that those with HPV infection were 32 times more likely to develop oropharyngeal cancer — regardless of the previously established risk factors of tobacco and alcohol use.
While there is no screening test for the cancer, Gillison said the risk is relatively low. "People should be reassured that oropharyngeal cancer is relatively uncommon, and the overwhelming majority of people with an oral HPV infection probably will not get throat cancer," said Gillison.
Gardasil, a vaccine that may protect against several strains of HPV, has not been specifically tested in relation to oral cancer. The Tories have set aside $300-million for an HPV vaccination program for girls aged nine to 11 but debate remains about the long-term effectiveness and morality of the plan.
According to the Canadian Cancer Society, 3,200 Canadians will get oral cancer in 2007 and 1,100 will die from the disease. [10May07, CTV.ca News http://www.ctv.ca/servlet/ArticleNews/story/CTVNews/20070510/oralsex_cancer_070510/20070510?hub=Health; N Valko RN, 11May07]
Throat cancer added to list of diseases caused by HPV: Study finds oral sex transmits virus in men and women."The study found that people who have had more than five oral-sex partners in their lifetime are 250 percent more likely to develop throat cancer than those who do not have oral sex." The study found that people who have had more than five oral-sex partners in their lifetime are 250 percent more likely to develop throat cancer than those who do not have oral sex. The cancer at one time was thought to be caused only by alcohol or tobacco. Gillison and others noted that the finding could explain why throat cancer, which includes the tonsils and back part of the tongue, is on the increase in nonsmokers in their 30s, 40s and 50s. Historically, it has occurred among heavy smokers and drinkers in their 60s and 70s. Those numbers are down.
The study, published in today's New England Journal of Medicine, comes a week after the Texas Legislature overturned Gov. Rick Perry's order requiring schoolgirls to be vaccinated against HPV. Perry chastised lawmakers Tuesday but declined to veto the bill. The study could shift the debate to whether the HPV vaccine eventually should be required of both males and females. Not only is the throat-cancer risk higher in men, noted Gillison, but if you add HPV-associated throat, anal and penile cancers, the virus causes as many cancers in men as women.
Dr. Erich Sturgis, a University of Texas M.D. Anderson Cancer Center professor of head and neck surgery, called the study "very important" and said it provides the best proof to date of the risk oral sex poses for throat cancer. "Partners of women who have abnormal Pap smears should be aware they're at risk," Sturgis said. Sturgis said M.D. Anderson is working on similar research it hopes to publish.
There are 11,000 HPV-associated cases of throat cancer a year, slightly more than the number diagnosed as cervical cancer. There is no simple swab test to indicate early onset of throat cancer. The treatment, surgery or intensive chemotherapy and radiation, is considered particularly difficult and causes speaking and eating problems.
Greatest risk factor
Gillison's team took blood and saliva samples from 100 patients with throat cancer — 86 males and 14 females — and from 200 healthy people.
The study found people who had a prior infection with HPV were 32 times more likely to have throat cancer than those with no evidence of having the virus. Those who tested positive for a particularly aggressive strain, HPV-16, were 58 times more likely.
HPV is ubiquitous, infecting men and women in equal numbers. Gillison said one study has found that, at any time, 10 percent of women have it.
Gillison had conducted previous research showing an association between oral sex, HPV and cancer but wanted to know whether those cases were a fluke. The study, she said, found HPV was the greatest risk factor, dwarfing the contribution of alcohol and tobacco. Gillison said she expects in time HPV-associated oral cancers will outpace those caused by alcohol and tobacco use. The study mostly was funded by the Damon Runyon Cancer Research Foundation. [12May07, Houston Chronicle, [email protected]; Donna Garner]
SEX AND ORAL CANCER — Infection with the human wart virus — HPV (Human Papilloma Virus) — which is the cause of cervical cancer, may be why oral cancer is becoming more common. The type of cell involved in mouth and cervical cancer is the same.
Two years ago Professor Saman Warnakulasuriya [King’s College London] presented findings on oral cancer [Royal College of Surgeons of Edinburgh]: 75% of the patients had lifestyles that included well-known risk factors for mouth cancers. In the past it was customary to attribute these to rotten or broken teeth, but either changing circumstances, or greater knowledge, has shown that the great risks for these tumors are smoking and too heavy an alcohol intake. Smoking cannabis represents a greater risk than smoking normal cigarettes. However, even after all known factors had been excluded, 25% of the patients had no obvious cause for the cancers. Fifty years ago 5 men developed mouth cancers for every woman; this has now changed to 2 to one. In the past ten years in Scotland there has been a 50% increase in the numbers of younger people developing oral cancer, and over the past 40 years a fourfold increase in those under 45 affected by it. Recent research by Dr Elaine M. Smith [Univ of Iowa, publ. Journal of the National Cancer Institute] shows HPV as a causative agent for oral cancers. HPV 16, one of the high-risk types of wart virus for cervical cancer, was the most frequently detected type of HPV found in the mouth and was present almost twice as often in cancer patients as it was in healthy subjects. [25MAR04, Dr Thomas Stuttaford The Times – London, England, UK; Abstinence Clearinghouse 31March04]