Can engaging in oral sex increase your risk of head and neck cancer?

In Western countries, head and neck cancer, particularly oropharyngeal cancer, has witnessed a concerning surge over the last 20 years. This increase is primarily due to an associated increase in human papillomavirus (HPV) infections, and as HPV is primarily transmitted through sexual contact, including oral sex, you may want to speak to your patients about the link between HPV, oral sex, and oropharyngeal cancer.

Risk factors for head and neck cancer

Head and neck cancers have surpassed cervical cancer in terms of prevalence in the US and the UK, according to an article in The Conversation.^[] This type of cancer affects the soft palate, the side and back walls of the throat, the tonsils, and the back one-third of the tongue. 

Although HPV is not the exclusive culprit behind head and neck cancer, its presence substantially increases the likelihood of developing oropharyngeal carcinoma. Other factors contributing to the risk include heavy smoking; industrial chemicals; prolonged exposure to harmful substances, like wood dust or paint fumes; and excessive alcohol consumption.^[] 

It’s worth noting that, although most HPV-associated oropharyngeal cancers present with locoregionally advanced disease, these tumors have a better prognosis than those related to heavy tobacco and alcohol use, according to Jeffrey A. Bubis, DO, MDLinx medical advisory board member. 

The role of HPV

It is hypothesized that many individuals in the general population contract HPV infections, but their immune systems can eliminate the virus within 2 years. However, individuals who smoke may experience difficulty clearing the infection due to the damaging effects of smoking on immune cells. This poor immune response increases the likelihood of viral damage and cancer development.

Low-risk strains, namely HPV-6 and HPV-11, can lead to the growth of benign warts in the mouth and throat, causing potential complications and airway obstruction. In high-risk HPV strains (HPV-16 and HPV-18), the virus continues to replicate and integrate into the host's DNA, potentially leading to the development of cancerous cells.^[]

Oral sex and oropharyngeal cancer 

HPV is primarily transmitted through sexual contact, including oral sex. Engaging in oral sex is a significant risk factor for oropharyngeal cancer, an epidemiological study published in the NEJM has shown.^[] Individuals with six or more oral-sex partners in their lifetime were 8.5 times more likely to develop this cancer compared to those who did not practice oral sex.

A PLOS One report has also observed that in the US, men, younger age groups, and individuals of White ethnicity are more likely to engage in oral sexual behaviors associated with oral HPV-16 infection and oral squamous cell carcinoma.^[]

Neil Gross, MD, a specialist in HPV-associated head and neck cancers at MD Anderson Cancer Center, emphasizes that a common misconception is that HPV-associated head and neck cancer is solely caused by oral sex.^[] In fact, he says, HPV-associated head and neck cancer can be transmitted through deep kissing, not just oral sex.

Other HPV-related cancers

Unlike oropharyngeal cancer, other HPV-associated cancers, like cervical cancer, have significantly decreased since 2005. While cervical cancer can be detected through regular pap smear screenings, no equivalent screening methods are available for head and neck cancers. 

Recognizing the symptoms

Symptoms of HPV-related head and neck cancer can be challenging to identify. They include a neck mass or swelling, painful deglutition, difficulty while eating, hoarseness of voice, a feeling of having something stuck in the throat, and persistent sore throat.^[]

Other symptoms, as listed by the Cleveland Clinic, are ear pain, sudden-onset snoring without associated weight gain, enlarged lymph nodes, and unexplained weight loss. High-risk patients need to seek medical attention if these symptoms persist for over 2 weeks.

Limiting risk factors

The Cleveland Clinic recommends advising patients to consistently use barrier methods, condoms, or dental dams to add an extra layer of protection while engaging in oral sex.

HPV vaccination

The three-round HPV vaccine, administered to males and females aged 9 to 45 years, is highly recommended. The Cleveland Clinic explains that it helps prevent HPV infection and lowers the likelihood of developing HPV-related cancers.

Many nations have implemented HPV vaccination initiatives for young girls to prevent cervical cancer. As reported by The Conversation, recent studies indicate that this immunization may have an indirect but positive impact on reducing HPV infection in the oral cavity as well. Furthermore, when young females in a community receive high vaccination coverage—above 85%—males may also experience benefits from herd immunity.

The US, Australia, and the UK have also extended their HPV vaccination recommendations to include young males, adopting a gender-neutral vaccination policy.