The frank remarks by actor Michael Douglas on the causes of throat cancer have helped to focus attention on a topic many are reluctant to discuss: the relationship between HPV and throat cancers. HPV can be spread from an infected partner to another person during oral sex. Some strains of HPV are known to cause cancer of the cervix in women and can also cause cancer of the mouth or throat. These strains are called high risk HPV.
mCancerPartner sat down with Thomas E. Carey, Ph.D., Donald A. Kerr Endowed Collegiate Professor of Oral Pathology and co-director of the Head and Neck Oncology Program at the U-M Comprehensive Cancer Center to discuss the connection between human papilloma virus, or HPV and throat cancers. He has developed the largest repository of head and neck cancer cell lines in the world including several HPV-positive cell lines.
mCancer Partner: The number of cases of throat cancers thought to be caused by HPV seems to be exploding. What can you tell me about these cancers and what the prognosis is for most patients?
Dr. Carey: Yes, there’s been an explosion in the number of cancers in the areas around the tonsils, called the oropharynx, that test positive for cancer-causing HPV. These areas, especially the tonsils, are suitable sites for high risk HPV virus infection. In some cases, possibly years after infection, a rearrangement in the virus occurs leading to overexpression of the viral oncoproteins and drives the infected cell to continually replicate, resulting in oropharyngeal cancer. In the mid-1990s, our research group found that about 60% of the oropharyngeal patients we studied were HPV positive. In 2002-2005, the next cohort we studied was 90% positive, and our most recent group was pretty close – about 88-89% testing positive for HPV. Yes, I call that an explosion.
But though high risk HPV has become a more prominent cause of oropharyngeal cancer than the traditional causes – smoking and alcohol – the good news from both mufti-instutional trials and our in-house clinical trials is that the response rate to treatment of HPV-induced oropharyngeal cancers is excellent. Something like 80% of these patients treated in our cancer center are survivors.
mCancer Partner: What are the symptoms for the mouth or throat cancers associated with HPV?
Dr. Carey: Persistent sore throat or ear pain, burning sensation when drinking orange juice or other acidic drinks, hoarseness, difficulty swallowing, or a visible or palpable lump in the neck are common warning signs.
mCancer Partner: How can HPV infection to the mouth and throat be prevented?
Dr. Carey: HPV is a highly infectious virus. Data indicates that at least 80% – 90% of us get infected with HPV when we become sexually active. Temper this with the fact that your risk is directly related to your number of sexual partners. So for people who are sexually active, your behavior can reduce your risk of infection by high-risk HPV. Infection can occur from a single act of intercourse or oral sex with someone with an active infection. Since it is not possible to tell if someone has an active HPV infection, consistent use of male latex condoms and avoiding unprotected oral sex with someone whose sexual history is not known to you can reduce the risk of infection.
For young girls and boys who are not sexually active, there are highly effective vaccines available that will prevent HPV from taking hold.
mCancer Partner: Tell me about your own research on HPV and cancers of the throat and mouth.
Dr. Carey: Our research group studies cancers of the throat and mouth. We are working to identify why some patients with HPV-positive tumors respond better to treatment than others so that new patient-appropriate therapies can be developed. This will help to extend survival and decrease the treatment intensity for better quality of life.
National Cancer Institute: HPV and Cancer
National Cancer Institute: Head and Neck Cancers
CDC Centers for Disease Control and Prevention: Male Latex Condoms and Sexually Transmitted Diseases
Continue reading articles about HPV and cancer:
- Top Myths about HPV
- HPV in head and neck cancer
- HPV vaccine and cervical cancer: Is this the new magic bullet?
- Risk factors shouldn’t guide decisions about HPV vaccine
The Head and Neck Oncology Program at the U-M Comprehensive Cancer Center provides advanced diagnostic techniques, management and rehabilitation for patients with cancers of the head and neck. The program works in collaboration with specialists in otolaryngology, radiation oncology, hematology/oncology, speech and language pathology, hospital dentistry and other related fields.
The University of Michigan Comprehensive Cancer Center’s 1,000 doctors, nurses, care givers and researchers are united by one thought: to deliver the highest quality, compassionate care while working to conquer cancer through innovation and collaboration. The center is among the top-ranked national cancer programs, and #1 in Michigan for cancer patient care. Seventeen multidisciplinary clinics offer one-stop access to teams of specialists for personalized treatment plans, part of the ideal patient care experience. Patients also benefit through access to promising new cancer therapies.