[Comparison of human papilloma virus genotypes in patient with leukoplakia and mild dysplasia and health persons by polymerase chain reaction]

Early detection of malignant and dysplastic lesions has been an aim for clinicians. Although leukoplakia is not associated with any special hystopathologic diagnosis, it is considered as a premalignant or precancerous lesion. Human Papilloma virus especially HPV16 and HPV18 has been detected in many oral leukoplakia lesions. The aim of this study is to evaluate the presence of HPV and its genotypes 11, 16, 18, 30s and 50s in common leukoplakia, oral hairy leukoplakia, mild dysplasia and compare it with healthy mucosa. Ten samples of each lesion were prepared and fixed in paraffin blocks. After DNA isolation, PCR was done by chelex-100 method. The results were analyzed by SPSS statistical software, Chi-Square and Fisher's Exact test with P Value of 0.05. Seven out of 10 common leukoplakia and OHL, 1 out of mild dysplasia and healthy mucosa were HPV+. Double comparison by Fisher exact revealed that there was a significant difference in frequency distribution of HPV between OHL and healthy mucosa [p=0./01] and also between OHL and Mild dysplasia[p=0./01].The difference between frequency distribution of HPV and of common leukoplakia and healthy mucosa[p=0./01],also between common leukoplakia and mild dysplasia [p=0./01] was significant, the difference between other groups was not significant. Results of the study suggest that there is no significant correlation between infection of HPV subtypes in the evaluated lesions. In other words, no significant relationship was shown between the infection of special subtype of HPV and common leukoplakia, OHL and mild dysplasia. According to the findings of this study, HPV probably has a role in the pathogenesis of leukoplakia.To investigate the role of various subtypes of this virus in leukoplakia lesions, further studies with more samples are needed