Researchers at Roswell Park Cancer Institute (RPCI) in Buffalo, New York, are strongly advocating a national discussion about the need to vaccinate both young men and women against HPV 16 to prevent head & neck cancers.
The call comes amid growing evidence that certain cancers of the head and neck are strongly linked to HPV 16, a specific strain of the human papillomavirus (HPV) that is one of the most common sexually transmitted diseases in the United States. It is estimated that approximately 70% of Americans, both men and women, will be infected with HPV at some point in their lives.
The types of cancer associated with HPV 16 occur mostly at the back (base) of the tongue, in the tonsils, and in the soft palate at the back of the throat, according to Thom Loree, MD, Chair of RPCI's Department of Head & Neck Surgery. Over the past 10 years, members of RPCI's Head & Neck Department have seen a threefold increase in the number of throat cancers they treat.
In 2007, Roswell Park researchers began testing all head and neck tumors treated at the Buffalo-based comprehensive cancer center for the presence of HPV DNA, says Saurin Popat, MD, FRCSC, FACS, Attending Surgeon in Head & Neck and Plastic & Reconstructive Surgery, RPCI. RPCI is one of few institutions in the nation to do so. Data from the ongoing testing have been combined with data from archived tumor samples to provide a clearer picture of how many head and neck cancers treated at RPCI test positive for HPV. To date, the total is around 50 to 60 percent.
There are more than 100 types of HPV - each identified by number - but only 70 have been described so far, explains Popat. Some HPV viruses, including 16 and 18, are transmitted sexually - not just through sexual intercourse, but through any skin-to-skin contact involving the mouth, vagina, vulva (the external female genitalia), penis, anus, or fingers.
HPV 16 and HPV 18 were previously identified as the cause of most cases of cervical cancer in the U.S. HPV has also been implicated in the development of some cancers of the vulva, vagina, anus, penis, and perineum (the area between the genitals and anus).
There is no cure for HPV, just as there is no cure for the common cold. In most people, an HPV infection will clear up on its own, but it can be passed on to other people during the infection period - just as with the common cold.
In some cases, the person may continue to be infected for decades without any symptoms. During that time, the infected person can infect others without knowing it. Over time, this "silent," chronic HPV infection increases the risk of developing certain cancers.
In 2006, the FDA approved the use of Gardasil, a vaccine that protects against HPV 6, 11, 16 and 18, for females between the ages of 9 and 26, to help prevent cancers of the cervix, vulva, and vagina, as well as genital warts.
The FDA has not approved the vaccine for males. The issue of extending approval to males to protect against HPV related cancers is under review, with a decision expected in June 2009.
Loree, Popat, and their RPCI colleagues see compelling evidence for extending the vaccine's protection to boys. Says Popat, "The side effects of the vaccine are so small, and the potential benefits are great." He notes that patients with throat cancer "have to undergo major treatment lasting several months, with an additional four to six months of recovery. Their ability to speak and swallow is affected. Generally, they do very well; however, it is a long, challenging road."
Based on the evidence to date, Loree says that "with increased vaccination against HPV, you'll see a decrease in cervical cancer and in throat cancers." He says if everyone stopped smoking and using tobacco in any form, and also got vaccinated against HPV, "we could eliminate head and neck cancers, and I'd be out of business."
The American Cancer Society estimates that 35,310 new cases of oral and oropharyngeal cancer are diagnosed every year - 25,310 of those in men - and 7,590 people, including 5,210 men, die of those cancers. Smoking, the use of chewing tobacco, and heavy alcohol use remain the leading causes of cancers of the head and neck.
Click here http://www.roswellpark.org/hpv to hear Roswell Park experts discuss the link between HPV and throat cancer.