Retrospective analysis of oncogenic human papilloma virus and Epstein-Barr virus prevalence in Turkish nasopharyngeal cancer patients.

Nasopharyngeal carcinoma (NPC) is associated with the Epstein-Barr virus (EBV). Human papilloma virus (HPV) has also been detected in NPC cases. In this retrospective study, we analyze the frequency of EBV and HPV infection in 82 Turkish patients with NPC. A total of 82 were evaluated for EBV and HPV. In situ hybridization (ISH) was performed for EBV. HPV-ISH and P16 immunohistochemistry used to determine the HPV status. Seventy-two of the 82 (87%) NPC patients were EBV-positive. The highest rate of EBV-positivity was found in undifferentiated NPC patients, which accounted for 65 of 68 (95.6%) undifferentiated cases. One of the 82 NPC patients whose tumor was non-keratinizing differentiated, contained HPV. Our data shows that EBV is closely associated with NPC in Turkey. We found lower rates of HPV-positivity in NPC patients than in North American populations. In addition, both EBV and HPV-negativity were more associated with decreased survival than EBV-positive cases.