Michael Douglas was diagnosed with throat cancer (oropharyngeal cancer) three years ago. He initially said it was caused by years of heavy smoking, alcohol abuse and stress. However, he recently told The Guardian newspaper that it was caused by oral sex (cunnilingus).

In an Interview with Guardian reporter, Xan Brooks, Douglas said that his type of cancer was caused by the human papillomavirus (HPV) "which actually comes from cunnilingus". His agent later said Douglas had been talking generally, and not about his own cancer, but the Guardian responded by publishing the sound recording of the interview that clearly showed he blamed oral sex for his cancer, and not years of drinking, smoking and stress.

Douglas first revealed details of his throat cancer in the David Letterman Show, in September 2010. So, what is the risk of developing throat cancer from oral sex? Gypsyamber D'Souza, PhD, MPH, from the Johns Hopkins School of Public Health, and team explained at the American Society of Clinical Oncology (ASCO) annual meeting in Chicago, Illinois, that throat cancers that arise from HPV do not appear to raise the risk for domestic partners of the same cancer.

Dr. D'Souza explained that in their pilot study, they found that the prevalence of HPV among partners/spouses of an affected patient was approximately 7%, no different from that of the general population.

The team found that the HPV 16 subtype was present in just 2% of female partners and 0% of male partners. HPV 16 is responsible for the majority of throat cancers. Of the partners/spouses who underwent a visual oral exam, none had cancer or pre-cancer.

D'Souza explained that the risk of developing head and neck cancers for people whose partners have HPV-related cancer is very low.

At a press briefing, D'Souza said "Many people become infected but are able to clear those infections."

The researchers added that partners who have been together for a long time probably already share whatever infections they have. No changes in physical intimacy are needed, they emphasized. Put more simply "Couples will infect each other with whatever they have anyway - oral sex will neither increase nor reduce infection risk". Oral sex with 6 or more partners raises risk of throat cancer, said one study In a study published in NEJM (New England Journal of Medicine), Dr Maura Gillison of Johns Hopkins Bloomberg School of Public Health in Baltimore, Maryland, USA, and team suggested that people who have oral sex with at least 6 different partners have a significantly higher risk of developing throat cancer.

The team recruited 100 patients who had recently been diagnosed with oropharyngeal cancer, as well as 200 "healthy" individuals (the control group).

They found that people who had at least 6 oral-sex partners during their lifetime were 3.4 times more likely to have throat cancer. Those with 26 or more vaginal-sex partners had a 3.1 times higher risk of developing throat cancer. What are the risk factors for throat cancer?Smoking - this is by far the most important risk factor for throat cancer. Regular, long-term, heavy smokers are 20 times more likely to develop some type of throat cancer compared to non-smokers.