Objective: To identify different characteristics of oral cavity and oropharyngeal cancer, and to determine the HPV-associated prevalence of these two tumor types in Thailand, which is unlike the Western countries.

Material and Method: Between 2010 and 2012, a cross-sectional study was performed in 23 oral cavity and 23 oropharyngeal cancer patients. HPV genome was studied in all of them from pathological confirmed fresh specimens. Risks of HPV infection were collected using self-reported questionnaire.

Results: The prevalence of HPV-related oropharyngeal cancer was significantly noted in 26.09% (p = 0.009), while no demonstrable HPV-associated prevalence in oral cavity cancer. In addition, the routes of HPV infection were not identifiable.

Conclusion: Oral cavity and oropharygeal cancers are not only anatomically distinct, but also greatly differed in their characteristics and pathophysiology. The percentage of HPV-related tumors in Thailand is considerably low when compared to the Western countries. However, the impact on treatment modification cannot yet be universally applied.

Keywords: Human papillomavirus, Oral cavity, Oropharynx, Head and neck cancer, Thailand, Asia, HPV infection, Oral cancer, Oropharyngeal cancer