Association of high-risk human papillomavirus infection with oral epithelial dysplasia.

OBJECTIVE

The aim of this study was to evaluate cases of oral epithelial dysplasia for biologically significant human papillomavirus (HPV) infection.

STUDY

DESIGN

Forty consecutive cases of high-grade dysplasia and 37 cases of low-grade dysplasia were examined for p16(INK4a) expression by immunohistochemistry. High-risk HPV infection was assessed in p16-positive cases using in situ hybridization. Proliferation index was assessed with MIB-1 immunohistochemistry.

RESULTS

Eleven of 40 high-grade dysplasias and one of 37 low-grade dysplasias were p16 positive. High-risk HPV was detected in seven cases of p16-positive high-grade dysplasia. The difference between high- and low-grade dysplasia was statistically significant (P = .01). HPV-positive high-grade dysplasias showed a distinctive histologic appearance and MIB-1 labeling pattern. Most high-risk HPV-positive cases were seen in the floor of mouth.

CONCLUSION

High-risk HPV was associated with a subset of cases of severe epithelial dysplasia/carcinoma in situ that demonstrated diffuse loss of squamous differentiation and a high proliferation index.