Oral health may be linked to HPV status of head and neck cancer
MedWire News: The chronic oral inflammatory disease periodontitis may be associated with human papillomavirus (HPV) status in individuals with head and neck squamous cell carcinoma (HNSCC), report researchers.
Their study findings show that among HNSCC patients, the odds for having HPV-positive tumors increased significantly with each millimeter of alveolar bone loss (ABL) ‑ an established measure of periodontitis.
If future studies in cancer-free populations can show that chronic local inflammation, as is found in periodontitis, plays a significant role in the natural history of oral HPV infection, the public health implications would be important, say Mine Tezal (State University of New York at Buffalo, USA) and colleagues.
"Periodontitis is easy to detect and may represent a clinical high-risk profile for oral HPV infection," they write in the Archives of Otolaryngology Head and Neck Surgery.
Other markers of oral health the team examined in the cohort of 124 HNSCC patients included caries, missing teeth, and fillings, but these showed no association with tumor HPV status, pointing to a potential causal link between inflammation and HPV.
This association is biologically plausible, say Tezal et al, since "mucosal damage, microulcerations, and consequent epithelial proliferation mediated by inflammatory cytokines released from periodontitis sites provide an idea environment for initial HPV infection and its persistence."
A total of 40.3% of study participants had tumors positive for HPV DNA, and a higher proportion of these tumors were from oropharyngeal cancers (65.3%) compared with oral cavity (29.0%) and laryngeal (20.5%) cancers.
HPV-positivity was also associated with significantly higher ABL, at 4.57 mm, than HPV-negativity, at 3.78 mm.
Indeed, after adjustment for potentially confounding factors such as age at diagnosis, gender, and smoking status, each millimeter of ABL increased the odds for having positive HPV status 2.6 times, report the authors.
The site of participants' tumors also had an effect on results, with a stronger association between ABL and HPV status in patients with oropharyngeal SCC (n=49; odds ratio [OR]=11.70) compared with those who had oral cavity SCC (n=31; OR=2.32), and laryngeal SCC (n=44; OR=3.89).
Tezal and co-workers suggest that although periodontitis is localized to structures surrounding the teeth, periodontal pocket contents ‑ including inflammatory cytokines, bacteria, viruses, enzymes, and toxins ‑ are continuously shed into saliva, and the fact that most HNSCC occurs at saliva-draining areas, supports its critical role in the disease.
By Sarah Guy