|
Practicing Oral Sex May Increase Throat Cancer Risk. |
|
|
|
Written by Theresa Maher
|
|
Friday, 11 May 2007 |
Individuals who practice oral sex with multiple partners may be at a greater risk of developing oropharyngeal cancer or throat cancer because they are exposed to infections by human papilloma virus or HPV, according to a study by researchers at the Johns Hopkins University.
Oropharyngeal cancer or throat cancer occurs in the region where the mouth ends and the throat begins.
Human Papilloma Virus or HPV is also implicated in the development of cervical cancer. Researchers said the risk of developing throat cancer through exposure to HPV was at least nine times greater in people who admitted to having oral sex with more than six partners. This risk was greater than that conferred by extensive use of tobacco and alcohol, the study said.
The new study indicated that HPV might play a more important role in development of head and neck cancers than previously thought. According to the American Cancer Society, oropharyngeal cancer can occur in base of tongue, the back wall of the throat, the soft palate and tonsils.
The American Cancer Society estimates about 34,360 new cases of oropharyngeal and oral cancers will occur among Americans in 2007. Some 7,550 people are likely to die from these cancers in 2007. The major risk factors for oropharyngeal cancer include tobacco, alcohol, UV light, poor nutrition and chronic irritation as experienced by people who wear ill-fitting dentures.
Human papillomavirus (HPV) infections that are responsible for 70 percent of cervical cancers are also implicated in the development of oropharyngeal cancers. the same HPV types namely 16 and 18 are found in throat cancer samples.
The new study published in the May 10 issue of The New England Journal of Medicine, indicates that oral sex many be the main mode of transmission of HPV between individuals. The study involved 86 men and 14 women newly diagnosed with oropharyngeal cancer. Around 200 healthy men and women acted as a control group.
The researchers examined the samples of blood and saliva from 100 men and women who were diagnosed with throat cancer. The participants were also questioned about sexual practices as well as any family history of the cancer.
Researchers reported a 32-fold increase in the risk of oropharyngeal cancer in individuals who were positive for HPV infection before the study began. The most common HPV type present in over 70 percent of the oropharyngeal cancers in the study was type 16.
People who smoke and drank in addition to being HPV positive were not at any increased risk of developing throat cancer when compared to HPV positive patients who did not smoke or drink. This finding seems to indicate HPV may be a greater risk factor in oropharyngeal cancers than smoking or drinking.
While oral sex with multiple partners was the primary route through which HPV was transmitted between individuals, researchers did not rule out mouth-to-mouth transmission.
"It's the virus that drives the cancer," said lead researcher Maura Gillison, an assistant professor of oncology and epidemiology at Johns Hopkins. "Since HPV has already disrupted the cell enough to steer its change to cancer, then tobacco and alcohol use may have no further impact." However she added one positive factor was that all people with oral HPV infections do not develop throat cancer.
Gillison said the HPV-linked oral cancers were steadily rising among the population since 1973 and that this trend will continue to increase. In future, HPV oral cancers might eclipse those developed from smoking and drinking.
However one positive trend here is that the survival rates of these cancers are also rising. "We're getting more intensive in our cancer treatments and seeing a survival benefit, but it may not be the therapy alone that's causing this. It could also be the increasing percentage of treatment-friendly HPV cancers," Gillison added.
According to the Centers or Disease Control and Prevention, an estimated 20 million people are currently infected with HPV.
It is not known if a cervical cancer vaccine approved by the FDA last June will be effective in preventing HPV-related oropharyngeal cancer as well. Larger studies are needed to highlight the role of HPV in the development of oropharyngeal cancer. Till then visual inspection during dental visits may be the best way to detect these cancers.
 Add as favourites (48)
Powered by AkoComment Tweaked Special Edition v.1.4.4 |
Health 
