RESUMO
Introduction: It has been always an area of diffuse clarity when you study malignancy and its pathogenesis. Recently, it has invited lot of interest among the researchers about the possibility of role of viruses in the initiation of carcinogenesis. Recent advances in the field of molecular biology and biotechnology have solved some problems with regard to pathogenesis. Human papilloma virus (HPV) and its role in the initiation of malignancy in the cervix is proven almost beyond doubt. Objectives: The present study is aimed at the role of two types of HPV 16 and 18 in the initiation of oral premalignant and squamous cell carcinoma. The study also aims at using polymerase chain reaction (PCR) in finding out the prevalence of these types diagnosed histologically as oral leukoplakia and oral squamous cell carcinoma and prevalence of its association with the habit of tobacco use. Materials and Methods:In the present study, 45 patients having histopathologically confirmed oral squamous cell carcinoma in the age range of 32-85 years were selected along with 20 histopathologically confirmed oral leukoplakia in the age range 22-66 years. All the samples were subjected to polymerase chain reaction. The PCR reaction was carried out in PTC 200 thermo-cycler [MJ Research Inc, Watertown, MA, USA]. Results: The site prevalence and co-infection rate of these two types of viruses are being analyzed using very simple non-invasive scrapings obtained from fresh scrapings and found to be really high. It was also observed that 73.3% (33/45) of the oral squamous cell carcinoma patients were positive for oral HPV type 16 while 71.1% (32/45) were positive for HPV type 18 infection and 57.7% (26/45) were found to have both HPV type 16 and HPV type 18 infections. Conclusions:HPV type 16, 18, and co-infection of both types showed high prevalence in oral squamous cell carcinoma.The prevalence of HPV type 18 was found to be higher than HPV type 16 and co-infection in oral leukoplakia. It was observed that the tongue and palate lesions in the oral squamous cell carcinoma patients showed high prevalence of HPV type 16, type 18, and co-infection compared with other sites.