The pharynx is the part of your throat behind your nose and mouth. It’s a 5-inch hollow tube that transports air through the trachea (also known as the “wind pipe”), and food and liquid through your esophagus. There are three parts of the pharynx: the uppermost section behind your nose called the nasopharynx, the lowermost section behind your voice box called the hypopharynx, and the middle section called the oropharynx. The oropharynx includes the back one-third of the tongue, tonsils, soft palate and the side and back walls of the throat.
Cancer in any part of the pharynx is known as pharyngeal cancer, and cancer specific to the oropharynx is called oropharyngeal cancer. Oropharyngeal cancer is a type of head and neck cancer that accounts for about 18,000 newly diagnosed cases in the U.S. every year.
The leading cause of head and neck cancers is smoking tobacco, and as smoking has become less common in recent years, so has the occurrence for most head and neck cancers. The exception to this is oropharyngeal cancer, which is drastically increasing, especially in the younger population. The cause of this steady rise is human papillomavirus (HPV) infection, a common sexually transmitted disease and a leading risk factor for oropharyngeal cancer. About 70% of all oropharyngeal cancers in the U.S. are caused by HPV. Tobacco and alcohol are still important factors for developing oropharyngeal cancers, but doctors now distinguish between HPV-related oropharyngeal cancers and HPV-negative oropharyngeal cancers; the good news is, HPV-related oropharyngeal cancers tend to be much more responsive to treatment.
“Cure rates are high for HPV-driven oropharynx cancer, particularly when the tumors are small and occur in non-smokers,” says Barbara Burtness, MD, a Yale Medicine medical oncologist. “In fact, treatments developed in an era of predominantly tobacco-initiated cancers may be more intensive than is necessary for patients with HPV-driven cancers.”
Clinical trials are now studying ways to reduce the toxicity of treatment for patients with HPV-driven oropharynx cancer, she says.