59P Prognostic impact of HPV status evaluation in head and neck squamous cell carcinomas

Worldwide, head and neck carcinomas represent the seventh most common cancer, with known risk factors such as alcohol consumption, use of various tobacco-based products, and infection with high-risk human papillomavirus (HR-HPV). Association with HPV infection has already been proven to represent an indicator of a better outcome for patients with oropharyngeal squamous cell carcinomas (SCC) only. This paper aimed to highlight the prognostic value of the HPV status in all head and neck squamous cell carcinomas (SCC), independent of the location, evaluated using both immunohistochemical (IHC) and molecular techniques, and to assess the p16 marker (clone 16P04, JC2) value for predicting HPV. In this paper, 114 consecutive head and neck SCC cases were included. The association of HPV infection in these carcinomas was based on the IHC expression of p16 (clone 16P04, JC2) and PCR-based determination of HR-HPV, according to the indications of the 8th edition of the American Joint Commission on Cancer and in cases with an inconclusive or equivocal IHC expression of p16. There were 20 females and 94 males with ages ranging from 32 to 86 years old. Most of the tumors were p16 negative (88.60%) and there were no statistically significant differences between HPV status and age (p=0.5714), gender (p=0.6973), or pT stage (p=0.5452). Kaplan-Meyer curves revealed a significant difference between the overall survival (OS) of the p16 positive SCC versus p16 negative cases (p=0.0472), independently of their location. Although HPV status has a well-proved prognostic impact on oropharyngeal SCC, p16 expression should be evaluated for all head and neck SCC, because it seems to be an outcome predictor, independently of the location or stage. When IHC expression of p16 is inconclusive or equivocal, the HPV status should be established by PCR-based determination.