Researchers from the University of Maryland and Harvard University have reported that the better survival among White patients compared with African-American patients with oropharyngeal cancer appears to be due, at least in part, to the higher prevalence of human papillomavirus (HPV)-related cancers in White patients. These results were published early online in Cancer Prevention Research on July 29, 2009. 

Human papillomaviruses are probably the sole cause of cancers of the cervix and have been associated with cancers of the vulva, vagina, penis, and rectum. Epidemiologic and molecular biology studies have also suggested that HPV infection may be associated with cancers of the head and neck. The overall frequency of HPV in benign and precancerous lesions ranges from 18.5% to 35.9%, depending upon the detection methodology. Researchers affiliated with an international study have also reported that oral infection with HPV is associated with the development of head and neck cancers. These authors concluded that HPV infection increased the risk of oropharyngeal cancer in both users and non-users of alcohol and tobacco. These authors also suggested that the more prevalent practice of oral sex may explain the increased incidence of tonsillar and base-of-the-tongue cancers since 1973.

Previous studies have also suggested that oropharyngeal cancer that is linked with HPV infection has different characteristics from oropharyngeal cancer that is linked with other causes such as smoking. Researchers involved in a U.S. multicenter trial have reported that oropharyngeal cancer that results from HPV infection appears to have a better prognosis than oropharyngeal cancer that is linked with other causes such as smoking.

To explore racial differences in head and neck cancer survival, researchers evaluated information from patients with Stage III or Stage IV head and neck cancer and no evidence of distant metastases. Patients were treated with a combination of chemotherapy and radiation therapy.

• Among patients with types of head and neck cancer other than oropharyngeal cancer, overall survival was similar in White and African-American patients.
• Among patients with oropharyngeal cancer, White patients had significantly better median survivals than African-American patients (69.4 months in White patients versus 25.2 months in African-American patients).
• HPV rates also differed by race: 34% of White patients had HPV-positive cancer compared with 4% of African-American patients.
• Among patients with HPV-negative cancer, survival was similar in African-American and White patients.

Comments: These results suggest that White patients have better oropharyngeal cancer survival than African-American patients at least in part because White patients are more likely to have HPV-related cancer. The reasons for the higher rates of HPV-related cancers among White patients remain uncertain but may involve differences in sexual behavior. 

Reference: Settle K, Posner MR, Schumaker LM et al. Racial survival disparity in head and neck cancer results from low prevalence of human papillomavirus infection in black oropharyngeal cancer patients. Cancer Prevention [early online publication]. July 29, 2009.