Agreement between L1 and E6/E7-based assays for detection of high-risk HPV in cervical, oropharyngeal and penile cancers.

AIMS: Human papillomavirus (HPV) molecular testing targets either the late gene L1 or early genes E6 and/or E7. Loss of L1 during integration is suggested to compromise sensitivity in samples associated with cancer, however, clear evidence for this is lacking. Our aim is to address this by performing a head-to-head comparison between assays targeting L1 vs E6/E7, using a series of high-grade and invasive disease samples within different biological matrices and anatomical sites. METHODS: We obtained 298 samples comprising of liquid-based cytology and biopsies of cervical cancer and cervical intraepithelial neoplasia grade 3, in addition to biopsies of penile and oropharyngeal cancers. Two commercially available HPV primary screening assays and two assays with extended genotyping were applied to the sample set targeting L1 (Abbott RealTime HR HPV Assay and Optiplex HPV Genotyping Test) and E6/E7 genes (Xpert HPV Test and EuroArray HPV Test). RESULTS: Agreement for high-risk HPV (hrHPV) for all samples types between the screening assays is over 88% and over 96% for the two genotyping assays. For HPV 16 agreement is over 90% for both screening and genotyping assays. Kappa statistics show good to very good agreement between the screening and genotyping assays for hrHPV and HPV 16. CONCLUSIONS: Analysis of the valid results from our data indicates that L1 and E6/E7 targeting assays show similar performance for detection of hrHPV in high grade cervical lesions and cancers of cervix, penis and oropharynx.

Papilloplex HR-HPV test has non-inferior clinical performance for detection of human papillomavirus infection: assessment using the VALGENT framework.

AIM: The Papilloplex high-risk human papillomavirus (hrHPV) test (Genefirst, Oxford, UK) is a single tube real-time HPV test which provides multiplex detection and separate identification of 14 hrHPV types. Here, we present the clinical validation of the test in SurePath samples in comparison to a clinically validated reference test, the GP5+/6+Enzyme ImmunoAssay (GP5+/6+EIA) using the VALGENT (VALidation of HPV GENotyping Tests) framework. METHODS: Clinical performance was assessed using 998 unselected, cervical screening samples enriched with 297 cytologically abnormal specimens (100 atypical squamous cells of unspecified significance, 100 low-grade squamous intraepithelial lesions, 97 high-grade squamous intraepithelial lesions). Cases were defined as women diagnosed with histologically confirmed cervical intraepithelial neoplasia two or more (≥CIN2, N=119) and controls defined as women with two subsequent negative cytology results (N=834). RESULTS: The Papilloplex HR-HPV test has non-inferior sensitivity for detection of cervical precancer (p=0.0001 for ≥CIN2 and p=0.0005 for ≥CIN3) and non-inferior specificity, compared with GP5+/6+EIA (pni=0.0167)). The assay also showed excellent or good agreement for overall hrHPV and nearly all individual HPV types as compared with GP5+/6+EIA/Luminex. CONCLUSION: The Papilloplex HR-HPV applied on cervical specimens stored in SurePath medium fulfils the international clinical accuracy criteria for use in cervical cancer screening.

Validation of EUROArray HPV test using the VALGENT framework.

BACKGROUND: Robust clinical and analytical validation of human papillomavirus (HPV) tests is a pre-requisite for their use in cervical cancer screening given the transience of most high-risk HPV infections. OBJECTIVES: To evaluate the EUROArray HPV test (PCR-based full HPV genotyping test) using the international validation of the VALGENT framework, which offers an opportunity to determine analytical and clinical performance according to internationally accepted performance metrics. STUDY DESIGN: A total of 1300 consecutive and 300 abnormal cervical samples derived from the Slovenian screening programme were tested with the EUROArray HPV test. Clinical performance for the detection of cervical intraepithelial neoplasia grade 2 and above (CIN2+) was performed and compared to a standard comparator test (Hybrid Capture 2). Intra- and inter-laboratory reproducibility of the assay was performed in a subset of 500 samples. RESULTS: The relative clinical sensitivity and specificity of EUROArray HPV vs HC2 was 0.93 (95% Confidence Interval (CI), 0.88-0.99; P non-inferiority(ni) = 0.1413) and 1.01 (95% CI, 0.99-1.02; Pni = 0.0001), respectively. Application of an a-posteriori cut-off for HPV16 led to relative values of 0.98 (95% CI, 0.92-1.03; Pni = 0.0076) and 1.00 (95% CI, 0.97-1.03; Pni = 0.007), respectively. The assay showed excellent intra- and inter-laboratory reproducibility (concordance ≥ 94%, Kappas ≥0.85). CONCLUSION: At the predefined cut-off, EUROArray HPV was less sensitive than HC2 for the detection of CIN2+. However, when an optimised cut-off was applied, EUROArray HPV fulfilled international criteria for its use in cervical cancer screening.