Role of HPV genotyping in risk assessment among cytology diagnosis categories: analysis of 4562 cases with cytology-HPV cotesting and follow-up biopsies.

Objective: Human papilloma virus (HPV) detection and genotyping are increasingly used in clinical risk assessment. We aimed to analyze HPV genotyping performance in risk stratification among cytology diagnosis categories.

Methods: Between January 1, 2015 and December 31, 2016, 4562 cases with cytology-HPV co-testing and biopsy follow-up were identified. HPV tests were performed on Cobas (n=3959) or Aptima (n=603) platforms. Of the biopsies, 669 demonstrated high-grade squamous intraepithelial lesions or worse.

Results: Pooled high-risk HPV testing had high overall sensitivity (97%) but low specificity (20%) and positive predictive value (20%) for biopsy-confirmed high-grade squamous intraepithelial lesions or worse. HPV16/18 genotyping had considerably improved specificity (81%) and positive predictve value (35%) in predicting high-grade squamous intraepithelial lesions or worse, especially in atypical squamous cells of undetermined significance and low-grade squamous intraepithelial lesion categories. Significantly more biopsy-confirmed high-grade squamous intraepithelial lesions or worse were detected by Aptima than Cobas testing, as measured by HPV16/18 (48% vs 33%, p<0.001), non-16/18 high-risk HPV (18% vs 13%, p=0.029), or all high-risk HPV genotypes (27% vs 19%, p<0.001). Aptima genotyping showed a significantly higher positive predictive value than Cobas genotyping for biopsy-confirmed high-grade squamous intraepithelial lesions or worse in the atypical squamous cells of undetermined significance category (47% vs 23%, p<0.05).

Conclusions: HPV genotyping was sensitive for biopsy-confirmed high-grade squamous intraepithelial lesions or worse in all cytologic categories, and is particularly valuable in risk evaluation for women with atypical squamous cells of undetermined significance and low-grade squamous intraepithelial lesions. The triaging role was greatly diminished in high-risk lesions (atypical glandular cells, atypical squamous cells, cannot exclude high-grade squamous intraepithelial lesions and high-grade squamous intraepithelial lesions) due to low specificity and positive predictive value. Aptima performance in risk management was superior to Cobas, with significantly higher positive predictive value for biopsy-confirmed high-grade squamous intraepithelial lesions or worse. Our results highlight the importance of careful data interpretation from studies using different HPV testing methods and the need to incorporate HPV E6/E7-mRNA testing into management guidelines.