Accuracy of EasyChip HPV blot genotyping assay to detect high-risk HPV genotypes in SurePath Papanicolaou specimens

Abstract

EasyChip HPV blot is a human papillomavirus (HPV) genotyping assay that can be potentially used for HPV assay validation or clinical HPV research. To evaluate its genotyping accuracy, we compared EasyChip HPV blot with quantitative real-time polymerase chain reaction (qRT-PCR)/type-specific PCR assays in the detection of 8 high-risk HPV genotypes. Archival SurePath Papanicolaou specimens with abnormal results and follow-up biopsy (n = 154) were selected retrospectively for HPV genotyping by EasyChip HPV blot. To determine the accuracy of the assay, qRT-PCR and type-specific PCR also were performed and results for 8 high-risk HPV genotypes were compared (HPV16, 18, 31, 33, 35, 45, 52, and 58). A total of 95 Papanicolaou specimens were qualified for data analysis. Concordance between EasyChip HPV blot and qRT-PCR/type-specific PCR assays was high, with a very good agreement for the 8 high-risk HPV genotypes (95%; kappa value: 0.894, 95% CI: 0.805-0.984) and for HPV16 and HPV18 (96%; kappa value: 0.899, 95% CI: 0.802-0.996). HPV16 was the most frequent HPV genotype by EasyChip HPV blot. The odds ratio of HPV16/18 for high-grade cervical intraepithelial neoplasia was 11.25 (95% CI: 3.93-32.31). EasyChip HPV blot is a reliable HPV genotyping assay that can be used for HPV assay validation or clinical HPV studies.