Prevalence of Human Polyomaviruses in Oral and Oropharyngeal Squamous Cell Carcinoma From Patients Treated at a Cancer Center in Sao Paulo, Brazil.

Head and neck squamous cell carcinoma (SCC) predisposing factors include smoking and alcohol consumption. However, other agents have been investigated, including viruses. We aimed to investigate the presence of DNA of four different types of human polyomavirus (HPyV) in the oral cavity and oropharyngeal SCC samples from an oncology center in Brazil and evaluate the association between HPyV detection and clinical and sociodemographic characteristics. Sixty fresh frozen samples from three different anatomical sites (tongue, floor of the mouth, and oropharynx, 20 samples for each region) were retrospectively selected. Data from medical records such as age, sex, alcohol consumption, smoking, tumor staging and death in less than 5 years of diagnosis were collected. DNA was extracted for the identification of MCPyV, BKPyV, JCPyV, and TSPyV using PCR followed by Sanger sequencing of positive samples. The identity of the generated DNA sequences was confirmed by alignment reference sequences. The investigation of the presence of HPyV DNA showed positivity of 5% for MCPyV (n = 3), 0% for both BKPyV or TSPyV, and 60% for JCPyV (n = 36). No association was found between the positivity of any HPyV in samples with any clinical or sociodemographic characteristics of the patients, nor with a certain anatomical site, except for the association between death in less than 5 years after diagnosis and positivity for JCPyV (p = 0.009). Positivity for HPyV in oral cavity and oropharyngeal SCC was low for MCPyV, high for JCPyV and null for BKPyV and TSPyV. Further studies should be carried out to better understand the high prevalence of JCPyV found in oral cavity and oropharyngeal SCC.