BUFFALO, N.Y. -- Human Papilloma Virus (HPV), once almost
exclusively associated with cancer of the cervix, is now linked to
head and neck cancer. According to a new University at Buffalo
study just published in the Archives of Otolaryngology -- Head
& Neck Surgery, a JAMA publication, gum disease is associated
with increased odds of tumors being HPV-positive.
Mine Tezal, DDS, PhD, assistant professor of oral biology in the
UB School of Dental Medicine who is the primary investigator on the
study, and a team of scientists from UB evaluated data from 124
patients diagnosed with primary head and neck squamous cell
carcinoma (HNSCC) between 1999 and 2007.
"The aim of the study was to test the presence of periodontitis,
a persistent inflammatory process and HPV-status of HNSCC," she
said.
Of the 124 tumor samples Tezal and her team studied, 50 were
positive for HPV-16 DNA and that subjects with HPV-positive tumors
had a significantly higher severity of periodontitis when compared
to subjects with HPV-negative tumors.
According to the National Cancer Institute, there has been a
steady increase in the prevalence of oropharyngeal cancers in the
U.S. since 1973 despite the significant decline in tobacco use
since 1965.
Tezal notes that this increase has mainly been attributed to
oral HPV infection.
Understanding the natural history of the oral HPV infection and
targeting factors associated not only with its acquisition but also
with its persistence, says Tezal, will lead to more effective
strategies, not only for prevention, but also for treatment.
"While there is an effective vaccine for cervical HPV infection
if given prior to the exposure of the virus (females 9-26; males
9-21), oral HPV infection can be transmitted at or any time after
birth, and the target population for a vaccine to prevent oral HPV
infection has not yet been defined," said Tezal.
Tezal pointed out that though many previous studies combined
periodontitis and dental decay as indicators of poor oral health,
dental decay was not significantly linked to tumor-HPV status in
the present study.
"The fact that only periodontitis was associated with tumor HPV
status points to the potential association of inflammation with
tumor HPV status," she says.
When Tezal and colleagues started their research about eight
years ago they were looking at the potential association between
chronic inflammation and head and neck cancers because the
importance of the local oral environment for malignant tumor growth
was widely accepted. However there wasn't research evaluating the
role of local oral factors in the natural history of HNSCC, Tezal
said.
"The next step in this research will be intervention studies to
test whether treating the sources of inflammation, like gum
disease, can reduce the acquisition and/or persistence of oral HPV
infection and improve the prognosis of HPV-related diseases," she
said.