Patients with oral cavity cancers who were nonsmokers were more likely than smokers to have tumors in sites associated with chronic dental trauma, according to results of a retrospective analysis.
Brendan J. Perry, BSc, MBBS, of the Princess Alexandra Hospital in Queensland, Australia, and colleagues sought to determine whether the location of oral cancers significantly differed in patients who did and did not smoke.
The researchers analyzed data from 724 patients, 390 of whom had mouth cancer and 334 of whom had oropharyngeal cancer. All patients underwent treatment between 2001 and 2011. Men comprised the majority of the cohort with mouth cancer (65%; n=255) and oropharyngeal cancer (79%; n=265).
Researchers determined 22% (n=87) of patients with mouth cancer were nonsmokers, and the majority of that group (61%; n=53) were women. The investigators determined 14% (n=48) of patients with oropharyngeal cancer were nonsmokers, and the majority of this subset (75%; n=36) were men.
Among current or former smokers, oral cavity lesions occurred more frequently in women than men (61% vs. 39%). However, in the nonsmoking cohort, oral cavity lesions occurred more frequently in men (72% vs. 28%).
Common sites of oral cavity cancers in smokers and nonsmokers were the lateral tongue, floor of mouth, alveolar ridge, buccal and retromolar trigone. Edge-of-tongue tumors — a site potentially associated with dental trauma — occurred significantly more frequently in nonsmokers than smokers (66% vs. 35%; P˂.001).
Larger tumors located on the floor of mouth and surrounding tissues were more frequently observed in the smoking cohort (10% vs. 1%).
Gingival and floor of mouth lesions — which could be associated with denture rubbing — were more common in older patients. Further, 26 patients had tumors near dental abnormalities.
“This is the first large study looking specifically at the possible importance of dental trauma in oral cavity carcinogenesis,” Perry and colleagues wrote. “We acknowledge that this study does not prove that chronic dental trauma causes cancer. However we believe that the data … suggest that it may be a more important and common carcinogen than is currently perceived, especially in cases involving nonsmoking female patients.”
Disclosure: The researchers report no relevant financial disclosures.