Immune cells and prognosis in HPV-associated oropharyngeal squamous cell carcinomas: Review of the literature

• First review on immunological features of HPV-associated oropharyngeal tumors.
• Patient outcome is associated to a high number of CD8, a low CD4/CD8 ratio and CD98 positive cells, and possibly absence of HLA1.
• CD4 and HLA2 are found insignificant in relation to patient outcome.

SummaryCurrently, oropharyngeal squamous cell carcinomas (OPSCC) are treated based on the traditional TNM-classification, although this scheme might be inadequate for the subgroup of human papillomavirus (HPV)-associated OPSCCs. It remains debatable whether this subgroup of patients with favorable prognosis should be offered altered treatment. Besides the well-known biomarkers of HPV and p16, new promising immune cells and markers might nuance the prognosis and treatment for patients with HPV+ OPSCC. We systematically reviewed the literature on immunological features of HPV-associated OPSCCs, and report that a high number of cytotoxic T cells (CD8s) and a low number of CD98 positive cells is associated with better outcome, while an increased CD4/CD8 ratio and a high human leukocyte antigen 1 (HLA1) intensity is most likely associated with worse outcome. These findings might contribute to future OPSCC staging and treatment.