Using the VALGENT-3 framework to assess the clinical and analytical performance of the RIATOL qPCR HPV genotyping assay

I Benoy; L Xu; D Vanden Broeck; M Poljak; A Oštrbenk Valenčak; M Arbyn; J Bogers

doi:10.1016/j.jcv.2019.09.008

Using the VALGENT-3 framework to assess the clinical and analytical performance of the RIATOL qPCR HPV genotyping assay

J Clin Virol. 2019 Nov:120:57-62. doi: 10.1016/j.jcv.2019.09.008. Epub 2019 Sep 20.

Authors

I Benoy¹, L Xu², D Vanden Broeck³, M Poljak⁴, A Oštrbenk Valenčak⁴, M Arbyn⁵, J Bogers⁶

Affiliations

¹ Laboratory of Molecular Pathology, AML Sonic Healthcare, Antwerp, Belgium; National Reference Centre for HPV, Brussels, Belgium; AMBIOR, Laboratory for Cell Biology & Histology, University of Antwerp, Antwerp, Belgium.
² Unit of Cancer Epidemiology, Belgian Cancer Centre, Sciensano, Brussels, Belgium.
³ Laboratory of Molecular Pathology, AML Sonic Healthcare, Antwerp, Belgium; National Reference Centre for HPV, Brussels, Belgium; International Centre for Reproductive Health, Ghent University, Ghent, Belgium.
⁴ Institute of Microbiology and Immunology, Faculty of Medicine, University of Ljubljana, Ljubljana, Slovenia.
⁵ Unit of Cancer Epidemiology, Belgian Cancer Centre, Sciensano, Brussels, Belgium. Electronic address: Marc.arbyn@Sciensano.be.
⁶ Laboratory of Molecular Pathology, AML Sonic Healthcare, Antwerp, Belgium; National Reference Centre for HPV, Brussels, Belgium; AMBIOR, Laboratory for Cell Biology & Histology, University of Antwerp, Antwerp, Belgium; International Centre for Reproductive Health, Ghent University, Ghent, Belgium.

PMID: 31569008
DOI: 10.1016/j.jcv.2019.09.008

Abstract

Background and objective: The VALGENT framework is developed to assess the clinical performance of HPV tests that offer genotyping capability. Samples from the VALGENT-3 panel are used to identify an optimal viral concentration threshold for the RIATOL qPCR HPV genotyping assay (RIATOL qPCR) to assure non-inferior accuracy to detect high-grade cervical intraepithelial neoplasia (CIN), compared to Qiagen Hybrid Capture 2 (HC2), a standard comparator test validated for cervical cancer screening.

Study design: The VALGENT-3 panel comprised 1300 samples from women participating in the Slovenian cervical cancer screening programme, enriched with 300 samples from women with abnormal cytology. In follow- up, 126 women were diagnosed with CIN2+ (defined as diseased) and 1167 women had two consecutive negative Pap smears (defined as non-diseased). All 1600 samples were analyzed with the RIATOL qPCR. Viral concentration was expressed as viral log10 of the number of copies/ml. A zone of viral concentration cut-offs was defined by relative ROC analysis where the sensitivity and specificity were not inferior to HC2.

Results: The RIATOL qPCR had a sensitivity and specificity for CIN2+ of 97.6% (CI: 93.2-99.5%) and 85.1% (CI: 82.9-87.1%), respectively, when the analytical cut off was used. At a cut off of 6.5, RIATOL qPCR had a sensitivity of 96.0% (CI: 91.0-98.7%) and a specificity of 89.5% (87.6-91.2%). At optimized cut off, accuracy of the qPCR was non-inferior to the HC2 with a relative sensitivity of 1.00 [CI: 0.95-1.05 (p = 0.006)] and relative specificity of 1.00 [CI: 0.98-1.01 (p = 0.0069)].

Conclusions: The RIATOL qPCR has a high sensitivity and specificity for the detection of CIN2 + . By using a fixed cut-off based on viral concentration, the test is non-inferior to HC2. HPV tests that provide viral concentration measurements or other quantifiable signals allow flexibility to optimize accuracy required for cervical cancer screening.

Keywords: Cervical cancer; HPV genotyping; Human papillomavirus; Test validation; VALGENT.

MeSH terms

Adult
Early Detection of Cancer
Female
Genotyping Techniques
Humans
Mass Screening
Middle Aged
Papillomaviridae / genetics*
Papillomavirus Infections / diagnosis*
Real-Time Polymerase Chain Reaction
Sensitivity and Specificity
Slovenia
Uterine Cervical Dysplasia / virology*
Uterine Cervical Neoplasms / virology*