Oncologists are increasingly looking at oral sex as a primary driver of an ‘epidemic’ of throat cancers.
Rates of a specific type – known as oropharyngeal cancer – have been rising since the mid-2000s and its main cause is a sexually transmitted infection.
Human papillomavirus (HPV) is usually linked to cervical cancer, which is why girls are vaccinated against it at a young age.
But oropharyngeal cancer has now become more common than cervical cancer in the US and the UK. And the number of lifetime sexual partners is the leading risk factor for this specific type of throat cancer.
Dr Hisham Mehanna an oncologist at the UK’s University of Birmingham wrote in the Conversation that people with six or more oral sex partners in their lifetime are 8.5 times more likely to get the cancer than people who do not practice oral sex.
This graph shows how the number of new cases of throat cancer has ticked upward in the US since 1999. It is rising by about one percent a year in women and three percent in men
In a study by Dr Mehanna, he found that 80 percent of men and women practice oral sex at some point in their lives.
And surveys suggest that those rates are rising particularly among women.
Writing in the Conversation, Dr Mehanna said: ‘Yet, mercifully, only a small number of those people develop oropharyngeal cancer. Why that is, is not clear.
‘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.’
A majority of throat cancers – around 70 percent – are caused by human papillomavirus (HPV), an umbrella of common sexually transmitted viruses which generally don’t cause symptoms and resolve on their own.
There is a highly effective vaccine for HPV, but rates are considerably lower than the 85 percent needed to reach ‘herd immunity’, the term that means enough people have been made immune so that the virus cannot spread.
Less than 60 percent of school children have received the HPV vaccine for various reasons including parental hesitancy and anti-vax sentiment.
HPV strain 16 is strongly linked to mouth and throat cancers. In recent years, the incidence of these HPV-related cancers has risen significantly, largely due to shifts in sexual behaviors, including the more frequent practice of oral sex, according to Henry Ford Health.
Dr Mehanna called on parents around the world to get their childrens vaccinated, as the shots are highly effective.
He said the vaccines work ‘only if coverage among girls is high – over 85 percent, ‘and only if one remains within the covered “herd”.
‘It certainly does not afford protection in countries where vaccine coverage of girls is low, for example, the US where only 54.3 percent of adolescents aged 13 to 15 years had received two or three HPV vaccination doses in 2020.’
He added that he coronavirus pandemic has introduced additional difficulties.
For one, schools were inaccessible for a time, making it harder to reach young people. Additionally, rising vaccine hesitancy or ‘anti-vax’ sentiment in several countries may be contributing to lower vaccination rates.
At the same time, condom usage among young people is at record lows.
An independent sample of men and women aged between 15 and 44 from 2011 to 2015 was conducted to show what the condom use was in relation to gender, age, race and education level.
When participants were asked about their last sexual experience, only 33.7 percent of males and 23.8 percent of females used a condom.
The survey was the first to cover Americans’ struggles with condoms during sex, from some saying that it ‘completely fell off’ to others who only uses it for part of the act.
More than 58,000 Americans were diagnosed with oral or pharynx cancer in 2024.
Those with six or more lifetime oral-sex partners are 8.5 times more likely to develop oropharyngeal cancer than those who do not practice oral sex
While 69 percent of people diagnosed survive beyond five years after diagnosis, the US recorded 12,230 deaths this year.
Meanwhile, about one in four Americans have HPV, though most don’t know it due to a lack of symptoms. This can be dangerous because more than 11,000 women with HPV go on to develop cervical cancer.
When a person receiving oral sex has HPV, they can pass it on to the person performing it.
When the virus enters the body through the throat, it lodges in deep crevices.
It disrupts the cell life cycle and cell death in the throat wall, causing some cells to grow out of control.
This can lead to the formation of cancerous cells that keep building up until they cause a tumor.
It usually takes years for the virus to develop into cancer in the throat.
HPV causes about 60 percent or oropharyngeal cancers. Photo courtesy of medbullets.com
Around 10 percent of men have oral HPV, and 3.6 percent of women, mostly of older age.
Most people with HPV won’t develop symptoms, and the immune system typically clears it within a few years. But people with some kind of flaw in their immunity are more likely to develop genital or mouth warts or cancers of the cervix and genitals.
A vaccine against HPV was introduced in 2006 for children as young as 11, though initially for girls. It was approved for boys in 2020.
While some adverse reactions have been reported, including fever, fatigue, and headache, 96 percent of these effects were deemed non-serious, and the shot’s benefits have been proven to far outweigh the risks.
The HPV vaccination rate is relatively low, at about 60 percent of teenage girls, compared to other developed countries like the UK, where 85 percent of teen girls have been vaccinated.
Unlike the US, the UK government offers a universal HPV vaccination program, which is free of charge for eighth-grade students, which is helping the country move ever closer to eliminating cervical cancer.
Getting vaccinated as a teenager is just as crucial for preventing oropharyngeal cancer, as HPV has been shown to cause 60 to 70 percent of cases.