Human papillomavirus (HPV) is a sexually transmitted infection (STI) that can lead to cancers of the mouth and throat — specifically oropharyngeal cancer.

Oropharyngeal cancer is a type of head and neck cancer that affects the oropharynx — the back of the throat. This includes the tonsils and the base of the tongue.

According to the National Cancer Institute (NCI), HPV can interfere with cells’ interaction with each other, causing them to multiply uncontrollably. Smoking and excessive alcohol consumption may increase the chance that an HPV infection will turn into cancer.

HPV is common. The Centers for Disease Control and Prevention (CDC) state that around 10% of males and 3.6% of females have oral HPV, and rates of infection increase with age. In most people, HPV goes away within 1–2 years, but some people have difficulty clearing the infection.

This article explains the link between HPV and oral cancer. It also details the symptoms and risk factors for oral cancer, as well as how effective the HPV vaccine is.

HPV and oral cancer

HPV is the most common STI in the United States. Some types of HPV do not cause any problems, while others can lead to cancer.

There are more than 100 types of HPV, and around 40 of them can spread to the genitals, mouth, or throat through direct sexual contact.

Researchers believe high risk types of HPV are causing an increase in the rate of oropharyngeal squamous cell carcinoma (SCC), which is the second most common type of skin cancer. These types of HPV can also cause cancers of the cervix and anus.

How does HPV cause oral cancer?

A 2019 article in the Journal of the American Academy of Physician Associates reported that oral HPV infections cause oropharyngeal SCC in fewer than 1% of cases. However, doctors do not yet know exactly how the infection develops into cancer.

The CDC estimates that HPV causes 70% of oropharyngeal cancers in the U.S. However, the CDC does not know whether HPV on its own can cause oropharyngeal cancer, and HPV can take years to turn into cancer. Other factors, such as smoking or chewing tobacco use, might need to interact with HPV for it to cause cancer.

High risk HPV

The NCI states that high risk HPV disrupts cells’ communication with each other. This can cause infected cells to multiply at an uncontrollable rate and form an area of precancerous cells. If these cells do not receive treatment, they may turn into cancer.

Risk factors for HPV

A person can get HPV if they have vaginal, anal, or oral sex with someone who has the virus. Vaginal and anal sex are the most common routes of transmission. A person can also get the virus through close skin-to-skin contact during sex. Additionally, a person who has HPV without symptoms can pass the virus to someone else.

A person can get HPV from having only one or multiple sexual partners, and symptoms may not show up for years after the initial infection.

Often, doctors find HPV-related cancer in young people who have never used tobacco or alcohol. People with this type of cancer tend to have a better outlook than those with cancer not linked to HPV. The American Cancer Society (ACS) says that this is most likely because cancers related to HPV shrink after chemotherapy and radiation therapy.

Symptoms of oral cancer

Some people with oropharyngeal cancer do not have any symptoms. Others may experience:

a sore throat or irritation that does not go away
red or white patches or pain, tenderness, or numbness in the mouth or lips
lumps, thickening, rough spots, or crusty or worn-away areas in the mouth
problems with chewing, swallowing, speaking, or moving the jaw or tongue
earaches
hoarseness or a change in voice
unexplained weight loss

Doctors may not find oral SCC until it has reached an advanced stage. This is because this type of cancer does not cause symptoms in the early stages.

Types of oral cancer

According to the ACS, high risk types of HPV cause most squamous cell cancers of the oropharynx. Doctors refer to this as HPV-positive cancer.

HPV rarely causes oral cavity cancer, which can affect the:

lips
inside lining of the lips and cheeks, known as the buccal mucosa
teeth
gums
front two-thirds of the tongue
floor of the mouth under the tongue
roof of the mouth, or hard palate
area behind the wisdom teeth, known as the retromolar trigone

Other types of oral cancer include:

Verrucous carcinoma: This is a rare type of squamous cell cancer most commonly found in the gums and cheeks. It grows slowly and rarely spreads.
Minor salivary gland cancers: These types of cancer start in the glands within the mouth and throat lining.
Lymphoma: This starts in the tonsils and the base of the tongue, both of which contain lymphoid tissue, which is part of the immune system.

HPV vaccine

The CDC recommends HPV vaccination to prevent an initial HPV infection. However, the vaccine cannot treat existing infections. For this reason, the CDC recommends that people get the vaccine before they have been exposed to HPV, around age 11 or 12.

The CDC also recommends the vaccine for anyone up to age 26 who is not already vaccinated. Some people aged 27–45 may also decide to take the vaccine after discussing the potential risks and benefits with their doctor.

Because the HPV vaccine protects people from the types of HPV that can cause oropharyngeal cancer, it may also protect them from these types of cancer.

Treatment

It is important for a person to consult a doctor if they have concerns about any possible symptoms of oral cancer.

Treatment for oropharyngeal cancer depends on how far the disease has progressed. For instance, doctors can surgically remove surface-layer cancer (stage 0), which has not started growing deeper into the layers of tissue.

Radiation therapy: For stage 1 and 2 HPV-positive cancer, a person is likely to receive radiation therapy aimed at the cancer and the lymph nodes in the neck. Alternatively, they may have surgery to remove the main tumor and the lymph nodes of the neck. In some cases, doctors may also recommend chemoradiation, which is a mix of chemotherapy and radiation.
Chemoradiation: Larger cancers in the back of the tongue, the soft palate, or the tonsils that have spread into nearby tissues or lymph nodes in the neck (most stage 1, 2, and 3 HPV-positive cancers) require treatment with chemoradiation. Some cases may be suitable for surgery.
Other treatments: Doctors usually treat stage 4 HPV-positive cancer that has spread to other parts of the body with either chemotherapy or cetuximab, a type of monoclonal antibody treatment. Alternatively, they may use a combination of the two. Some people might also receive immunotherapy or radiation therapy, depending on their symptoms.

If oropharyngeal cancer keeps coming back, doctors treat it according to its location and the size of the tumor.

Prevention

A person can avoid HPV and any resulting oropharyngeal cancer by correctly using condoms and dental dams during sex. These barrier methods can lower a person’s chances of transmitting or contracting the virus.

Because smoking and alcohol use may contribute to HPV’s development into cancer, a person can also reduce their risk by avoiding alcohol and tobacco products and passive smoke exposure.

Summary

HPV is the most common STI in the U.S. Researchers think that high risk types of HPV are responsible for the rising rate of oropharyngeal cancer. Other factors, such as smoking and alcohol use, may increase the chance that HPV will progress to cancer.

The CDC recommends using condoms and dental dams during sex, avoiding tobacco and excessive alcohol use, and getting the HPV vaccine to prevent HPV and any resulting oropharyngeal cancer.

The link between HPV and oral cancer