Brush-based self-sampling in combination with GP5+/6+-PCR-based hrHPV testing: high concordance with physician-taken cervical scrapes for HPV genotyping and detection of high-grade CIN.

BACKGROUND Studies have shown that self-sampling for hrHPV testing (HPV self-sampling) is highly acceptable to women, increases screening participation rate, and may therefore further reduce cervical cancer incidence. However, it is important to clinically validate HPV self-sampling procedures for screening purposes. OBJECTIVES Clinical validation of combined brush-based self-sampling with GP5+/6+-PCR EIA for primary cervical screening. In addition, HPV type-specific agreement between sample types and acceptability of brush-based self-sampling were evaluated. STUDY DESIGN 135 women referred for colposcopy took a self-sample at home prior to vaginal- and cervical sampling by a gynaecologist. All women were biopsied for histology. HPV testing was done by GP5+/6+-PCR EIA, with genotyping by reverse line blotting (RLB). Acceptability of sampling methods was measured with a questionnaire. RESULTS In this outpatient population, hrHPV test results showed good concordance between self-samples and physician-taken cervical scrapes (86%, k=0.70), with sensitivities and specificities for CIN2+ that did not differ significantly (93% and 51%, 91% and 51%, respectively (P=1.0)). The clinical sensitivity of brush-based self-sampling combined with GP5+/6+-PCR EIA hrHPV testing for detection of CIN2+ was non-inferior to that of hrHPV testing on physician-taken cervical samples (P=0.018). In addition, hrHPV genotyping results were highly concordant between sample types, with almost perfect agreement for HPV16 (k=0.81) and HPV18 (k=0.92). Finally, 91% of participants described brush-based self-sampling as easy-to-use. CONCLUSIONS Brush-based self-sampling in combination with GP5+/6+-PCR EIA hrHPV testing is acceptable to women and valid for assessing the risk of CIN2+ in comparison to hrHPV testing on physician-taken scrapes. In addition, there was high concordance of HPV genotyping results. Therefore, this HPV self-sampling procedure may be considered for use in routine cervical screening.