The sexually transmitted virus that causes some cervical cancers can also cause cancer in the upper throat, researchers at Johns Hopkins Kimmel Cancer Center report.
The human papilloma virus, more commonly known as HPV, is linked to throat cancers most often in younger, married college graduates, according to the study published in the March 12 issue of the Journal of the National Cancer Institute. The connection grows stronger with larger numbers of oral sex partners and increasing marijuana use.
Other head and neck cancers are more often associated with smoking tobacco, alcohol use and poor oral hygiene, suggesting they may be a separate disease, said Dr. Maura L. Gillison, associate professor of oncology and epidemiology at Hopkins and lead researcher on the study.
“Our results indicate that HPV-positive and HPV-negative head and neck cancers have different risk-factor profiles and should be considered two distinct diseases,” Gillison said. “They just happen to occur in the same place.”
More research will need to be done to clarify the relationship to marijuana use, she said.
“It?s possible that other behaviors linked with marijuana use could be the real culprit, and our results will need to be confirmed,” she said. Chemicals in marijuana called cannabinoids could affect the immune system?s ability to fight a virus.
About 20 million Americans are currently infected with HPV, and another 6.2 million people become infected each year, according to the Centers for Disease Control and Prevention.
At least half of all sexually active men and women will have a genital HPV infection at some point in their lives.
This year, 11,070 women will be diagnosed with cervical cancer in the U.S., the American Cancer Society estimates. A significant portion of cervical cancers are caused by HPV.
The good news is, patients with HPV-positive tumors tend to survive longer and are more responsive to treatment, compared with patients with HPV-negative tumors.
The American Joint Committee on Cancer is now considering incorporating HPV status in its guidelines for determining clinical stages of head and neck cancer.
