Performance of a cartridge-based assay for detection of clinically significant human papillomavirus (hpv) infection: Lessons from Valgent (Validation of HPV Genotyping Tests)

Abstract

The Validation of Human Papillomavirus (HPV) Genotyping Tests (VALGENT) studies offer an opportunity to clinically validate HPV assays for use in primary screening for cervical cancer and also provide a framework for the comparison of analytical and type-specific performance. Through VALGENT, we assessed the performance of the cartridge-based Xpert HPV assay (Xpert HPV), which detects 14 high-risk (HR) types and resolves HPV16 and HPV18/45. Samples from women attending the United Kingdom cervical screening program enriched with cytologically abnormal samples were collated. All had been previously tested by a clinically validated standard comparator test (SCT), the GP5/6enzyme immunoassay (EIA). The clinical sensitivity and specificity of the Xpert HPV for the detection of cervical intraepithelial neoplasia grade 2 or higher (CIN2) and CIN3relative to those of the SCT were assessed as were the inter-and intralaboratory reproducibilities according to international criteria for test validation. Type concordance for HPV16 and HPV18/45 between the Xpert HPV and the SCT was also analyzed. The Xpert HPV detected 94% of CIN2and 98% of CIN3lesions among all screened women and 90% of CIN2and 96% of CIN3lesions in women 30 years and older. The specificity for CIN1 or less (