Sensitivity of tumor surface brushings to detect human papilloma virus DNA in head and neck cancer

Abstract

Objective: Human papilloma virus (HPV) induced head and neck squamous cell carcinoma (HNSCC) represents a distinct tumor subset. We questioned how accurately a brushing from the tumor surface detects HPV in patients with HNSCC.

Materials and methods: Brushings from the tumor surface were compared with HPV DNA isolation from formalin-fixed and paraffin-embedded (FFPE) tumor biopsies, which served as the reference standard. In both matrices, HPV DNA was detected using a commercially available test kit. In addition, p16 was assessed in tumor biopsies by immunohistochemistry (IHC). The tumors were considered p16 positive if 70% or more of cancer cells expressed p16.

Results: 93 patients with HNSCC were included. Sensitivity and specificity of the brush test were 83% (95%CI: 67-92%) and 85% (95%CI: 72-93%). Results of p16 IHC were concordant with FFPE samples DNA determinations in 73/93 patients. In 53 patients (57%) the tumor was located in the oropharynx and in 40 patients (43%) the tumor was located in the non-oropharynx region. Sensitivity and specificity of the brush test in patients with oropharyngeal cancer was higher with 86% (95%CI: 70-95%) and 89% (95%CI: 65-99%).

Conclusion: Superficial brushes from the tumor surface may be used to identify HPV positive HNSCC.

Keywords: Brush test; Head and neck cancer; Human papillomavirus; p16.