Detection of circulating HPV16 DNA as a biomarker in the blood of patients with human papillomavirus-positive oropharyngeal squamous cell carcinoma

BACKGROUND: Development of biomarker analysis using the circulating cell-free DNA (cfDNA) methodology is a challenge for noninvasive cancer diagnosis. In this study, a comparison between the plasma and tumor tissue HPV16 DNA viral loads (VLs) has been presented. METHODS: Real-time polymerase chain reaction was performed for quantitating of HPV16 DNA in the plasma and tumor samples of patients with oropharyngeal cancer. RESULTS: Among the tissues, HPV16-positive patients with oropharyngeal squamous cell carcinoma, nonsmoking patients, displayed significantly higher HPV16 DNA VLs in their tissue. No smoking and advanced N disease were the most important predictors for cHPV16 DNA (circulating HPV16 DNA) detection. The cHPV16-positive women displayed significantly higher VLs in their tumor tissues compared to the men, although without notable impact on the blood detection. CONCLUSIONS: Many factors were responsible for human papillomavirus DNA circulation in blood. As a result of the small size of the analyzed group, some observed discrepancies need to be proven on a larger cohort.