Big Blow for Lovers
Scientists have today revealed that casual sex can endanger our health more than smoking or drinking. Researchers found patients who previously had oral sex-linked infections were 32 times more likely to develop throat cancer – much higher than the threefold increase for smokers and 2½-fold for drinkers.
Published in the New England Journal of Medicine, the study found conclusive evidence that human papillomavirus (HPV), which can be caught by having multiple oral sex partners, is the strongest risk factor for the disease.
The study, carried out by researchers at the Johns Hopkins Kimmel Cancer Center, looked at 100 men and women newly diagnosed with oropharyngeal cancer. Participants who reported having more than six oral sex partners were 8.6 times more likely to develop the HPV-linked cancer.
Surprisingly, the data showed that smoking and drinking didn’t increase the risk of HPV carriers developing throat cancer. Maura Gillison M.D., study author and professor of oncology, said, “It’s the virus that drives the cancer. Since HPV has already disrupted the cell enough to steer its change to cancer, then tobacco and alcohol use may have no further impact.”
Oral HPV infection is transmitted mainly by fellatio and cunilingus, although mouth-to-mouth transmission remains possible. Both men and women contract the virus in equal numbers, but Gillison adds, “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.”
Still, it is worrying to learn that not only smoking ‘cancer sticks’, but sucking on them, can cause the deadly disease.
N Engl J Med. 2007 May 10;356(19):1944-56.
Case-control study of human papillomavirus and oropharyngeal cancer.
* D’Souza G, * Kreimer AR, * Viscidi R, * Pawlita M, * Fakhry C, * Koch WM, * Westra WH, * Gillison ML.
Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, Baltimore, USA.
BACKGROUND: Substantial molecular evidence suggests a role for human papillomavirus (HPV) in the pathogenesis of oropharyngeal squamous-cell carcinoma, but epidemiologic data have been inconsistent. METHODS: We performed a hospital-based, case-control study of 100 patients with newly diagnosed oropharyngeal cancer and 200 control patients without cancer to evaluate associations between HPV infection and oropharyngeal cancer. Multivariate logistic-regression models were used for case-control comparisons. RESULTS: A high lifetime number of vaginal-sex partners (26 or more) was associated with oropharyngeal cancer (odds ratio, 3.1; 95% confidence interval [CI], 1.5 to 6.5), as was a high lifetime number of oral-sex partners (6 or more) (odds ratio, 3.4; 95% CI, 1.3 to 8.8). The degree of association increased with the number of vaginal-sex and oral-sex partners (P values for trend, 0.002 and 0.009, respectively). Oropharyngeal cancer was significantly associated with oral HPV type 16 (HPV-16) infection (odds ratio, 14.6; 95% CI, 6.3 to 36.6), oral infection with any of 37 types of HPV (odds ratio, 12.3; 95% CI, 5.4 to 26.4), and seropositivity for the HPV-16 L1 capsid protein (odds ratio, 32.2; 95% CI, 14.6 to 71.3). HPV-16 DNA was detected in 72% (95% CI, 62 to 81) of 100 paraffin-embedded tumor specimens, and 64% of patients with cancer were seropositive for the HPV-16 oncoprotein E6, E7, or both. HPV-16 L1 seropositivity was highly associated with oropharyngeal cancer among subjects with a history of heavy tobacco and alcohol use (odds ratio, 19.4; 95% CI, 3.3 to 113.9) and among those without such a history (odds ratio, 33.6; 95% CI, 13.3 to 84.8). The association was similarly increased among subjects with oral HPV-16 infection, regardless of their tobacco and alcohol use. By contrast, tobacco and alcohol use increased the association with oropharyngeal cancer primarily among subjects without exposure to HPV-16. CONCLUSIONS: Oral HPV infection is strongly associated with oropharyngeal cancer among subjects with or without the established risk factors of tobacco and alcohol use. Copyright 2007 Massachusetts Medical Society.