RESUMEN
BACKGROUND: To date, no studies have successfully shown that a highly specific, blood-based tumour marker to detect clinically relevant HPV-induced disease could be used for screening, monitoring therapy response or early detection of recurrence. This study aims to assess the clinical performance of a newly developed HPV16-L1 DRH1 epitope-specific serological assay. METHODS: In a multi-centre study sera of 1486 patients (301 Head and Neck Squamous Cell Carcinoma (HNSCC) patients, 12 HIV+ anal cancer patients, 80 HIV-positive patients, 29 Gardasil-9-vaccinees, 1064 healthy controls) were tested for human HPV16-L1 DRH1 antibodies. Analytical specificity was determined using WHO reference-sera for HPV16/18 and 29 pre- and post-immune sera of Gardasil-9-vaccinees. Tumour-tissue was immunochemically stained for HPV-L1-capsidprotein-expression. FINDINGS: The DRH1-competitive-serological-assay showed a sensitivity of 95% (95% CI, 77.2-99.9%) for HPV16-driven HNSCC, and 90% (95% CI, 55.5-99.7%) for HPV16-induced anal cancer in HIV-positives. Overall diagnostic specificity was 99.46% for men and 99.29% for women ≥ 30 years. After vaccination, antibody level increased from average 364â¯ng/ml to 37,500â¯ng/ml. During post-therapy-monitoring, HNSCC patients showing an antibody decrease in the range of 30-100% lived disease free over a period of up to 26 months. The increase of antibodies from 2750 to 12,000â¯ng/ml mirrored recurrent disease. We can also show that the L1-capsidprotein is expressed in HPV16-DNA positive tumour-tissue. INTERPRETATION: HPV16-L1 DRH1 epitope-specific antibodies are linked to HPV16-induced malignant disease. As post-treatment biomarker, the assay allows independent post-therapy monitoring as well as early diagnosis of tumour recurrence. An AUC of 0.96 indicates high sensitivity and specificity for early detection of HPV16-induced disease. FUNDING: The manufacturer provided assays free of charge.