Actuality: Pharyngeal cancer (PhC) is a malignant neoplasm in the oropharynx and nasopharynx associated with Epstein-Barr viruses (EBV) and human papillomavirus (HPV). Both viruses have oncogenic potential, affecting the pathogenesis of PhC. EBV, which infects more than 90% of the population, can cause various benign and malignant diseases. HPV, especially types 16 and 18, is the main oncogenic factor of oropharyngeal cancer (OPhC). The E6 and E7 proteins produced by HPV disrupt the action of tumor suppressors p53 and Rb, which leads to uncontrolled cell proliferation. EBV activates latent proteins and regulates the immune response, whereas HPV affects cell cycle control by inactivating p53 and Rb. HPVinduced PhC has a better prognosis compared to EBV-associated cancer due to higher sensitivity to treatment. Purpose: Systematization of literature data to assess the diagnostic and prognostic significance of EBV and HPV associated with PhC, to improve programs for early diagnosis and primary prevention of head and neck tumors Methods: A literature review has been conducted on the keywords of the study in the PubMed and MedLine databases since 2015. Results: Studies show that EBV and HPV are important in the diagnosis and prognosis of PhC. The EBV presence in tumor cells can mark a more aggressive course of the disease. However, in some cases, it is associated with better treatment results. Patients with HPV-positive tumors have better prognoses and a more favorable response to treatment compared to HPV-negative cases. Both viruses play an important role in the pathogenesis of PhC, and their diagnosis and characterization can significantly affect treatment tactics and prognosis of the outcome of the disease. Conclusion: EBV and HPV play a key role in the pathogenesis of RG, but their mechanisms of action and clinical outcomes differ. EBV is more often associated with nasopharyngeal cancer and HPV with oropharyngeal cancer, and the latter is more common in Western countries and shows a more favorable prognosis. Future research should focus on developing more effective prevention, diagnosis, and treatment methods for these viruses.
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