Oral Sex Is a Leading Factor in the Throat Cancer ‘Epidemic’ in the United States, Doctor Says

Oral sex may be the biggest factor in the rise of throat cancer in the United States.

Dr. Hisham Mehanna — a professor at the Institute of Cancer and Genomic Sciences at the University of Birmingham — said that there has been a “rapid increase” in oropharyngeal cancer, a type of throat cancer, in the past two decades, calling it an “epidemic” in both the U.S. and U.K.

“For oropharyngeal cancer, the main risk factor is the number of lifetime sexual partners, especially oral sex,” Mehanna wrote for The Conversation. “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.”

The Centers for Disease Control and Prevention states that 70% of oropharyngeal cancers in the United States are caused by HPV, or human papillomavirus.

HPV is the most common sexually transmitted infection, with 3 million new cases in the U.S. each year. Many people will live their lives without ever knowing that they have HPV, but for some, it can develop into cancer.

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According to the American Cancer Society, cases of oropharyngeal cancer linked to HPV increased yearly by 1.3% in women and by 2.8% in men between 2015 and 2019.

Though people with HPV infections often “clear them completely,” Mehanna said others can develop severe symptoms.

“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,” he explained. “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.”

The CDC notes that it typically takes years after being infected with HPV for cancer to develop. The health agency also states that it is unclear if having HPV alone is enough to cause oropharyngeal cancers, or if other factors — like smoking or chewing tobacco — interact with HPV to cause these cancers.