Sexually transmitted throat cancer?
A novel connection between throat cancer and the human pappillomavirus (HPV) has been investigated recently in the New England Journal of Medicine. Although throat cancer has been linked to this virus previously, the present study provides the first behavioural link between the two.
HPV infections, which often produce no immediate symptom, were already known to cause cervical cancer. The virus produces localized infections. "It doesn't spread through the bloodstream," says oncologist Maura L. Gillison of Johns Hopkins University in Baltimore. Therefore, an HPV infection acquired through sexual intercourse affects only the genital region, she says, and oral sex may expose the throat and tonsils to a similar viral infection and cancer
HPV-specific proteins, designated HPV-16, for the viral strain likely to cause cancer provides a biomarker for previous infections. Indeed, according to the study these proteins were found in over 70% of the throat cancers!
Gillison and her colleagues report that the throat cancer patients were
three times as likely as the other people to have had six or more
partners on whom they had performed oral sex at some time. And patients
whose throat cancers contained the HPV-16 DNA were nearly nine times as
apt to have had six or more such sex partners.
"It's worth considering the possibility that some oral, oropharyngeal,
and laryngeal cancers might be prevented by HPV vaccination," dentist
Stina Syrjänen of the University of Turku in Finland says in the
journal issue carrying the new study.
A vaccine is currently available in Europe for specific strains of HPV, while nothing of its kind has been approved for sale in North America.
That vaccine is being recommended to protect girls and young women
against cervical cancer. The link between HPV and throat cancers
suggests that boys, too, might benefit from the vaccine, Gillison says.