Role of human papilloma virus in oral tongue squamous cell carcinoma.

BACKGROUND: Human papilloma virus (HPV) is an important risk factor for head and neck cancer, specifically oropharyngeal cancer, but its association with oral tongue squamous cell carcinoma (SCC) is uncertain. The objectives were to determine the HPV16 prevalence in oral tongue SCCs, its integration status and to correlate the expression of oncogenic proteins with targets. METHODS: In this case-control study with oral tongue SCC cases (n=60) and normal oral mucosa (n=46), HPV positivity was determined by polymerase chain reaction (PCR) using consensus and HPV 16 type specific primers and p16 immunohistochemistry (IHC). The viral integration status was determined with primers specific to the E2 gene and in situ hybridization (ISH). Immunohistochemical analysis of HPV oncogenic proteins (E6, E7) and their target proteins (p53, pRb, cyclinD1, p16, Notch-1, EGFR) proteins was carried out in HPV positive cases. The data was analyzed with SPSS software (v 11.0). Survival analysis was carried out by the Kaplan-Meier method. RESULTS: HPV16 was detected in 48% (n=29) of the cases and none of the controls by PCR assay (p<0.001) while p16 IHC, as a surrogate HPV marker, detected 33% (n=18) of the cases; 18% (n=10) were detected by both the methods. Integration was observed in 83% (n=24) by E2-PCR and 67% (n=18) by ISH. The E6-p53 pathway was active in 33% of the cases; E7-pRb in 52% and both in 11%. HPV positivity was associated with well-differentiated cancers (p=0.041) and low recurrence rate (p=0.014). CONCLUSION: Our study confirms a positive correlation of HPV infection with oral tongue cancer.

Mouth self-examination to improve oral cancer awareness and early detection in a high-risk population.

Oral cancer is a potentially preventable disease due to its association with well-known risk factors and easy detectability. There is a significant deficiency in the awareness of oral cancer and its risk factors among the public. Raising public awareness could effectively contribute to achieving a significant reduction in the incidence of oral cancer. The objective of this study was to evaluate the effectiveness of mouth self-examination (MSE) in improving the awareness of oral cancer and its risk factors as well as test its feasibility as an oral cancer-screening tool. The study was carried out in a high-risk population of 57,704 from India, of which, 34,766 individuals who have met the eligibility criteria formed the study population. MSE brochures and trained health workers were employed for the purpose of health education and cancer screening. The present study compared their efficacy to detect oral lesions. Subjects with suspicious lesions were referred to the trained oral cancer specialist for confirmation. A questionnaire to assess the awareness of oral cancer and its risk factors was developed and validated. SPSS (v.11.0) was used for data analysis. The program identified 216 cases of potentially malignant lesions as well as three cases of oral cancer. The findings of MSE and health workers showed 72% concordance, while that of health workers and oral cancer specialist showed 100% concordance. MSE had a low sensitivity of 18%, while the specificity was 99.9%. Though the technique identified high-risk lesions such as red patches (66.7%) and non-healing ulcers (42.9%), the detection rate of white patches was low (12.7%). Overall awareness of oral cancer and its risk factors after introduction of MSE program was over 80%; but the compliance to seek treatment was poor (32%). Mouth self-examination may be used as an effective tool to improve the awareness of oral cancer and for the early detection of lesions.