The incidence of throat cancer is increasing because of a rise in HPV-related tumors, accounting for 30 percent of all head and neck cancers in the developed world.
It might seem unlikely that head and neck cancers can be caused by HPV (human papillomavirus), which is most commonly contracted through sexual contact. Most head and neck squamous cell cancers are related to tobacco use, and the incidence of this cancer overall is decreasing in developed countries because of a decline in smoking.
HPV generally infects humans through the skin or mucous membranes. Infections are common and usually do not result in clinical symptoms. Of the more than 100 HPV types, some are low risk, potentially causing warts or other benign growths. High-risk types can cause genital and oropharyngeal, or throat, cancer. The oropharynx is the area in the back of the throat that includes the tonsils and the base of the tongue, and it is the site of most HPV-related head and neck cancers.
Who is at risk?
Oral HPV infection is more common in men and smokers. Infection does not necessarily lead to cancer, and there is no way to know which individuals exposed to HPV will go on to have cancer. More than 90 percent of people with an HPV infection will clear the infection within two years. However, some who do not clear the virus will go on to develop HPV-related cancer years later.
How is it diagnosed?
Most patients with HPV-related throat cancer first become aware of an enlarged lymph node in the neck. Often, there are few other signs because the primary tumor is usually small. Larger tumors can cause throat pain, difficulty swallowing, a change in voice, ear pain and weight loss. These symptoms warrant an evaluation by a head and neck surgeon, who will perform a biopsy.
How is it treated?
The treatment of HPV-related throat cancer can include surgery, radiation and sometimes chemotherapy. Radiation alone can treat the early stages of the disease. More advanced stages may require the addition of chemotherapy to increase the tumor’s sensitivity to radiation. Surgery was traditionally used to treat these tumors, but the older approaches have significant side effects related to changes in speech and swallowing.
Newer and less invasive techniques using transoral robotic surgery allow patients to return home the next day without the risks of more invasive surgical approaches. This offers the possibility of lowering or avoiding radiation in select cases, or avoiding chemotherapy altogether.
What are the chances for survival?
The good news is that survival rates for patients with HPV-related throat cancer are promising, especially for nonsmokers. Over 85 percent of patients without a smoking history can be cured. Patients should seek care from head and neck cancer specialists, who are more experienced and knowledgeable about treatment options.
What can I do?
It is common to feel anxiety about the association between HPV infection, transmission and an increase in cancers. But it is important not to feel embarrassed. While HPV infection is common, HPV-related oropharyngeal cancer is uncommon, and the chance of developing this kind of cancer remains low. Paying attention to signs and symptoms, stopping smoking, and ensuring that eligible family members are vaccinated are the best tips for early detection and prevention.
Christine Gourin is associate professor of otolaryngology – head and neck surgery – at the Johns Hopkins Hospital in Maryland.