Detection of Circulating HPV16 DNA as a Biomarker for Cervical Cancer by a Bead-Based HPV Genotyping Assay

Human papillomavirus (HPV) circulating tumor DNA (HPV ctDNA) was proposed as a biomarker for the detection and disease monitoring of HPV-related cancers. One hundred eighty plasma samples obtained from women diagnosed with HPV16-positive cervical cancer (CC) ( = 100), HPV16-positive premalignant lesions (cervical intraepithelial neoplasia grade 3 [CIN3]) ( = 20), and HPV DNA-negative controls ( = 60) were randomly selected from the archives for evaluating the performance of a bead-based HPV genotyping assay (E7 type-specific multiplex genotyping assay [E7-MPG]) in detecting HPV16 ctDNA. The performance of the E7-MPG was compared with those of DNA detection by droplet digital PCR (ddPCR) and detection of HPV16 E6 antibodies evaluated in an independent study. Internal controls to assess DNA quality were included in the molecular assays, i.e., beta-globin and ESR1, respectively. The sensitivity and specificity of E7-MPG and/or E6 antibodies to detect HPV16-positive CCs were evaluated. HPV16 ctDNA was detected using the E7-MPG in 42.3% of all plasma samples and in 74.7% of plasma samples from HPV16-positive CC cases. The validation of E7-MPG data by ddPCR showed that the sensitivity of the E7-MPG test for HPV16-positive CC detection was higher than that of ddPCR (74.7% versus 63.1%;