What You Need to Know About HPV-Associated Head & Neck Cancer
The human papillomavirus (HPV) infection is the most commonly diagnosed sexually transmitted disease in the United States. The U.S. Centers for Disease Control and Prevention estimates that each year about 8,400 Americans are diagnosed with HPV-related oropharyngeal cancer.
HPV is a sexually transmitted virus that is associated with condyloma acuminatum, squamous intraepithelial lesions, and malignancy, including anogenital malignancies (cervical, vaginal, vulval, penile, and anal carcinoma), and head and neck squamous cell carcinoma.
Many patients with oropharyngeal squamous cell carcinomas, particularly those in the base of the tongue and in the tonsillar region where they are most commonly found, do not have any of the traditional risk factors associated with head and neck cancers (such as smoking, smokeless tobacco, or alcohol consumption).
The rate of HPV-linked head and neck cancer has been rising — particularly among white adults younger than 55. We’re not seeing as many older men with head and neck cancer due to drinking and smoking as we used to. But we have seen a rise in men who are not drinkers and smokers…and they are HPV16 positive.
- Recent studies suggest that HPV may account for much as 70 to 80 percent of oropharyngeal cancers in North America and Europe.
- The timing between exposure to HPV and the development of oropharyngeal cancer may exceed 10 years.
- Patients whose non-oropharyngeal tumors were positive for p16 had a better prognosis compared with those who were p16 negative.
- Worldwide, there is a significant increase in oropharyngeal cancer in men in developed countries, with it occurring at young ages.
- In one study of 164 patients with oropharyngeal cancer, oral HPV was detected in 65 percent of cases, and an oncogenic HPV strain was identified in 61 percent; 88 of 100 positive for oncogenic HPV had HPV16. Among the 93 partners available for testing, the overall incidence of HPV infection was 4 percent, and only one had the oncogenic HPV16. The virus somehow seems to stay in the mouth longer than in the cervix.
- The vast majority of HPV-associated head and neck cancers are squamous cell carcinomas.
- Patients with HPV-positive oropharyngeal cancer are approximately 10 years younger when compared to HPV negative patients.
- HPV-associated tumors mostly arise in the base of the tongue or the tonsillar region, although a small percentage of tumors at other sites are also HPV positive. Why the oropharynx is more susceptible than other sites to HPV transformation is unclear. However, the oropharynx offers easy access for infection. The tonsils contain deep invaginations of the mucosal surface believed to favor the capture and processing of antigens, which may facilitate viral access to basal cells.
- HPV-associated oropharyngeal cancer is more likely to present with an early stage (T1/T2) primary tumor, but relatively advanced disease in the neck (N2/N3), often with a large regional lymph node than is sometimes mistaken for a cyst.
Patients with HPV-associated oropharyngeal cancer generally have a better prognosis at presentation and after disease recurrence, compared with patients whose disease is not associated with HPV.
Cancer treatment for patients with HPV-associated oropharyngeal cancer currently is the same as for those with HPV negative oropharyngeal cancers, except in the context of a clinical trial. Although testing for HPV positivity provides prognostic information, not enough data exists to alter therapy based upon HPV status. Preliminary studies suggest that HPV-associated oropharyngeal cancers may be successfully treated with a lower dose of radiation than is required for HPV-negative tumors.
WHAT TO LOOK FOR:
- A lump in the neck is the most common symptom associated with HPV-related head and neck cancer
- Other persistent, advanced symptoms can include problems swallowing and ear pain
- As a PCP, you need to be especially vigilant for clues because (1) patients tend to ignore their own symptoms; (2) not many studies have been done for understanding the symptoms of HPV-related cancer; and (3) it’s generally easier to regard a symptom as a common infection rather than cancer
- If you have any doubts about symptoms presented, the best advice is to refer your patient to an ENT for further diagnosis
- If your patient has already experienced an HPV-associated head and neck cancer, it is far less likely for a second head and neck malignancy to develop compared to patients who have smoking-associated head and neck cancer.
- There is an HPV vaccine (currently two vaccines, Gardasil and Cervarix, have market approval here). Both vaccines protect against the two HPV types (HPV-16 and HPV-18) that cause 70% of cervical cancers, 80% of anal cancers, 60% of vaginal cancers, and 40% of vulvar cancers.
- The World Health Organization and public health officials in the U.S. recommend that females be vaccinated prior to sexual activity.
- The HPV vaccine also is effective in males to protect their partners from HPV infection or themselves from anal cancer, genital warts, and possibly other HPV-associated cancers.
- HPV is a sexually transmitted virus that is associated with condyloma acuminatum, squamous intraepithelial lesions, and malignancy, including anogenital malignancies (cervical, vaginal, vulval, penile, and anal carcinoma), and head and neck squamous cell carcinoma.
- HPV-associated head and neck cancers occur primarily in the tonsils and base of tongue. HPV-associated malignancies now account for more than one-half of cancers of the oropharynx in the United States and Western Europe. High-risk HPV infection may also be causative in some cases of other head and neck cancer cancers.
- HPV-associated head and neck cancers affect younger patients without a history of excessive exposure to alcohol and tobacco.
- HPV-associated oropharyngeal cancers tend to present with regional lymph node metastases relatively early in the natural history of the disease. Despite this, these cases are associated with a better prognosis and response to therapy than HPV negative tumors due to other risk factors. Tumor testing for HPV status may be useful in patients with oropharyngeal cancer as a prognostic marker.
- Although the HPV status of oropharyngeal cancers has significant prognostic implications, there is insufficient evidence to alter therapy based upon HPV status outside the context of a clinical trial.
- HPV-related head and neck cancer symptoms can belie their seriousness and need to be examined carefully; especially lumps in the neck. Any doubt of symptoms should be referred to an ENT.
- An HPV vaccine exists and should be recommended to all pre-teen females prior to sexual activity. Young males should also be vaccinated.
Jennifer W. Gerson, M.D., a radiation oncologist with OHC, has a special interest in head and neck cancers. Dr. Gerson practices at the following locations: Blue Ash, Fairfield, West, and Wilmington, Ohio.