HPV prevalence and p16INKa overexpression in non-smoking non-drinking oral cavity cancer patients.

OBJECTIVE

Our aim was to compare HPV and p16INK4a (p16) expression and their influence on survival and prognosis in oral cavity squamous cell cancer (OCSCC), between non-smokers and non-drinkers (NSND) and smokers and drinkers (SD).

SUBJECTS AND METHODS

Patients with OCSCC treated with surgery from 2000 to 2010 were included in the study. Patients who did not smoke at all or smoked less than 10 pack per years and did not drink alcohol on a daily basis were considered the NSND group. An equal number of SD were the control group. HPV presence was determined from paraffin-embedded blocks investigated by PCR analysis. p16 expression was evaluated with immunohistochemistry.

RESULTS

The NSND group were mostly younger or older female patients with tongue or gingival cancers. p16 expression was significantly more frequent in NSND patients (27% vs 10%). Patients with stronger p16 expression had significantly worse survival, especially for tongue cancers (P = 0.026). In Cox multivariate analysis, both HPV and p16 expression carried a negative prognosis for NSND patients (P = 0.0351 and P = 0.0260).

CONCLUSIONS

NSND are a specific population of OCSCC patients. In contrast to oropharyngeal cancer, HPV and p16 expression in OCSCC are negative predictive factors, especially in NSND patients.