Doctors are diagnosing a very rare type of head and neck cancer with more frequency. Narsopharyngeal cancer, a tumor that grows behind the nose and at the top of the throat, above the tonsils, generally occurs in less than 1 of every 100,000 Americans. Researchers at the University of Michigan Comprehensive Cancer Center in Ann Arbor believe this rare cancer is linked to the human papillomavirus or HPV.
“Though rare, this is the first report of nasopharyngeal cancer being caused by the HVP epidemic. We are in the middle of a tonsil cancer epidemic, seeing many more patients with tonsil cancer linked to HPV. It turns out that HPV may also be a new cause of this rare form of cancer that occurs in this hidden location,” says study author Carol Bradford, M.D., professor and chair of otolaryngology at the University of Michigan Medical School.
In the study, which appears online in the journal Head and Neck, the researchers looked at tissue samples taken before treatment for either nasopharyngeal cancer or tonsil cancer. Of the 89 patients in the study, five had nasopharyngeal cancer, and four of those were positive for HPV.
At the same time, the four HPV-positive tumors were also all negative for Epstein-Barr virus, which has previously been one of the biggest infectious causes of nasopharyngeal cancer. Epstein-Barr is a member of the herpes virus family and one of the most common human viruses.
“Since I began studying head and neck cancer, I have wondered what the cause of Epstein-Barr virus-negative nasopharyngeal tumors might be. This research suggests that there is a changing etiology for nasopharyngeal cancer in the North American population that may mirror the HPV-positive epidemic of tonsil cancer,” says study author Thomas Carey, Ph.D., professor of otolaryngology and pharmacology and co-director of the head and neck oncology program at the University of Michigan Comprehensive Cancer Center.
In addition to being linked to oropharyngeal cancer, HPV, a group of more than 100 related viruses, is also believed to be the primary cause of cervical cancer. Additionally, HPV may also play a role in cancer of the anus, vulva, vagina and penis, as well as genital warts.
Overall, about 60 percent of nasopharyngeal cancer patients are five years survivors after treatment. In fact, death rates for this type of cancer have declined 4 percent per year. The researchers suspect one potential reason is that HPV-related tumors are more responsive to chemotherapy or radiation than tumors linked to the Epstein-Barr virus.
Because nasopharyngeal cancer is so rare, the researchers propose a multi-center trial to recruit more patients to verify the role of HPV in nasopharyngeal cancer. The University of Michigan Cancer AnswerLine can provide more information at 800-865-1125.
Source: Head & Neck, published online Sept. 15, 2009, DOI:10.1002/hed.21216
Azsunshinegirl, aka Lynette Summerill, is an award-winning journalist who lives in Scottsdale, Arizona. In addition to writing about cancer-related issues, she writes a blog, Nonsmoking Nation, which follows global tobacco news and events.