As the demand for human papillomavirus (HPV)-related cervical screening increases, novel HPV tests must be evaluated using well-annotated samples. The Validation of Human Papilloma virus (HPV) Genotyping Tests (VALGENT) framework is an international collaboration designed to facilitate the clinical validation and comparison of HPV assays that offer genotyping capabilities. Here we present the data from three assays; BD Onclarity HPV assay (BD), Genomica CLART4s (CLART) and Agena MassArray HPV assay (MA).
In total, the Valgent4 consists of 1000 consecutive screening samples and an enriched subset of 300 samples equally divided between samples with ASCUS, LSIL and HSIL, all collected in SurePath LBC medium from Danish routine cervical screening. Briefly, the Onclarity assay is a real time PCR assay that detects 14 HR-HPV genotypes in nine groups (16,18,31,45,51,52,33/58, 56/59/66,35/39/68), the CLART4 assay is a PCR-based Microarray full genotyping assay that detects 36 genotypes (the 14 HR-HPV types and 22 non-HR HPV types), and the MA is a full genotyping MALDITOFF-based assay that detects 19 genotypes (the 14 HR-types and 5 non-HR-types). Here, the analysis is limited to HR-HPV genotypes only.
Onclarity, CLART4 and MA detected 371, 455, and 514 positives samples respectively. 947 samples had normal cytology, 106 ASCUS, 121 LSIL and 124 ≥HSIL. Histological follow-up at 12 months after initial sample collection resulted in 118 normal histology results including 29 ungraded CIN, 43 CIN1, 31 CIN2, 64 CIN3 and 7 cancers. The assays showed overall good pairwise HR-HPV detection concordance of 87-92%. At individual HR-HPV genotype level, the concordance varied from 40-84% (Onclarity vs MA), 32-62% (Onclarity vs CLART4) and 32-66% (CLART4 vs MA). HPV16, 18 and 31 had the highest pairwise assay concordance. For samples with ≥CIN2 outcome, the pairwise assay concordance was higher for almost all genotypes detected by the three assays. The sensitivity for detection of ≥CIN2 was 95%, 98% and 96% for Onclarity, CLART4 and MA, respectively.
The three genotyping assay had overall good concordance at HR-HPV level, whereas on genotype level the discordance became noticeable. Genotypes HPV16, 18 and 31 had the highest pairwise concordance between the three assays. Comparison with a validated standard comparator test, planned later, will allow verification whether these tests fulfill the requirement s for use in cervical cancer screening.