Oral sex is now the leading risk factor for throat cancer, according to experts who describe the recent rapid rise of the disease in the last two decades as an epidemic.
Writing in The Conversation Professor Hisham Mehanna, from the Institute of Cancer and Genomic Sciences at the University of Birmingham, said that “this has been due to a large rise in a specific type of throat cancer called oropharyngeal cancer (the area of the tonsils and back of the throat).”
He said that the main cause of this cancer is the human papillomavirus (HPV), which is also the main cause of cancer of the cervix – adding that the throat cancer “has now become more common than cervical cancer in the US and the UK”.
“HPV is sexually transmitted. For oropharyngeal cancer, the main risk factor is the number of lifetime sexual partners, especially oral sex,” he explained.
The medical expert said that people with multiple partners were almost nine times more likely to develop the throat cancer.
“Those with six or more lifetime oral-sex partners are 8.5 times more likely to develop oropharyngeal cancer than those who do not practise oral sex,” he said.
“The prevailing theory is that most of us catch HPV infections and are able to clear them completely. However, a small number of people are not able to get rid of the infection, maybe due to a defect in a particular aspect of their immune system. In those patients, the virus is able to replicate continuously, and over time integrates at random positions into the host’s DNA, some of which can cause the host cells to become cancerous,” Professor Mehanna wrote.
He said that HPV vaccination of young girls has been implemented in many countries to prevent cervical cancer, and that this “may also be effective in preventing HPV infection in the mouth”, but cautioned that “when dealing with populations and behaviour, nothing is simple or straightforward”.