Comparing the performance of 2 human papillomavirus assays for a new use indication: a real-world evidence-based evaluation in the United States.

BACKGROUND: The US Food and Drug Administration supports innovations to facilitate new indications for high-risk human papillomavirus testing. This report describes the retrospective testing of stored specimens and analysis of existing data to efficiently and cost-effectively support a new indication for the Onclarity human papillomavirus assay (Becton, Dickinson and Company, BD Life Sciences - Integrated Diagnostic Solutions, Sparks, MD). The performance of this index test was compared with that of a predicate test, the cobas human papillomavirus assay (Roche Diagnostics, Indianapolis, IN). Both human papillomavirus assays are based on real-time polymerase chain reaction platforms that detect the presence of 14 high-risk human papillomavirus genotypes. The predicate assay reports human papillomavirus types 16 and 18 as individual results and the other 12 human papillomavirus genotypes as 1 pooled result. The index assay reports 9 independent results (human papillomavirus types 16, 18, 31, 33/58, 35/39/68, 45, 51, 52, and 56/59/66). Both the index and predicate assays are approved by the Food and Drug Administration for cervical cancer screening, but at the time that this study was initiated, the index human papillomavirus assay was not approved for use with cervical specimens collected in PreservCyt (Hologic, Inc, San Diego, CA) liquid-based cytology media. OBJECTIVE: The performance of the index human papillomavirus assay was compared with that of the predicate human papillomavirus assay for the detection of cervical intraepithelial neoplasia grades 2 or greater and 3 or greater (≥CIN2 or ≥CIN3) using PreservCyt liquid-based cytology specimens collected from women aged 21 to 65 years. In addition, the ability of the index test's extended genotyping to stratify ≥CIN2 and ≥CIN3 risks, using these specimens, was evaluated. STUDY DESIGN: The New Mexico HPV Pap Registry was used to select an age- and cytology-stratified random sample of 19,879 women undergoing opportunistic cervical screening and follow-up in routine clinical practice across New Mexico. A subset (n = 4820) of PreservCyt specimens was selected from 19,879 women for paired testing by the index and predicate human papillomavirus assays within age and cytology strata and included women with or without cervical biopsy follow-up. Point estimate differences and ratios were calculated for cervical disease detection and positivity rates, respectively, with 95% confidence intervals to determine statistical significance. The cumulative risk of ≥CIN2 or ≥CIN3, with up to 5-year follow-up, was estimated for the index assay using Kaplan-Meier methods. RESULTS: The 5-year cumulative ≥CIN3 detection rates were 5.6% for the index assay and 4.6% for the predicate assay (difference, 1.0%; 95% confidence interval, 0.5%-1.5%). The ≥CIN3 positivity rates within <1 year were 95.3% for the index assay and 94.5% for the predicate assay (ratio, 1.01; 95% confidence interval, 0.98-1.06). The ≥CIN3 cumulative positivity rates for the index and predicate assays were also similar at 5 years. Among cases of ≥CIN3, the positive agreement rates between the index and predicate assays for human papillomavirus types 16 and 18 were 100.0% (95% confidence interval, 95.0%-100.0%) and 90.9% (95% confidence interval, 62.3%-98.4%), respectively. Human papillomavirus type 16 carried the highest ≥CIN2 or ≥CIN3 risk, followed by human papillomavirus types 18/31/33/58/52/45 and human papillomavirus types 35/56/59/51/56/59/66. CONCLUSION: The index and predicate human papillomavirus assays demonstrated equivalent performance, and extended human papillomavirus genotyping, using the index assay, provided effective ≥CIN2 and ≥CIN3 risk stratification, supporting a new indication for use of the index assay with PreservCyt.

Relationships of p16 Immunohistochemistry and Other Biomarkers With Diagnoses of Cervical Abnormalities: Implications for LAST Terminology.

CONTEXT.­: Lower Anogenital Squamous Terminology (LAST) standardization recommended p16INK4a immunohistochemistry (p16 IHC) for biopsies diagnosed morphologically as cervical intraepithelial neoplasia (CIN) grade 2 (CIN2) to classify them as low-grade or high-grade squamous intraepithelial lesions (HSILs). OBJECTIVE.­: To describe the relationships of p16 IHC and other biomarkers associated with cervical cancer risk with biopsy diagnoses. DESIGN.­: A statewide, stratified sample of cervical biopsies diagnosed by community pathologists (CPs), including 1512 CIN2, underwent a consensus, expert pathologist panel (EP) review (without p16 IHC results), p16 IHC interpretation by a third pathology group, and human papillomavirus (HPV) genotyping, results of which were grouped hierarchically according to cancer risk. Antecedent cytologic interpretations were also available. RESULTS.­: Biopsies were more likely to test p16 IHC positive with increasing severity of CP diagnoses, overall (Ptrend ≤ .001) and within each HPV risk group (Ptrend ≤ .001 except for low-risk HPV [Ptrend < .010]). All abnormal grades of CP-diagnosed biopsies were more likely to test p16 IHC positive with a higher HPV risk group (Ptrend < .001), and testing p16 IHC positive was associated with higher HPV risk group than testing p16 IHC negative for each grade of CP-diagnosed biopsies (P < .001). p16 IHC-positive, CP-diagnosed CIN2 biopsies were less likely than CP-diagnosed CIN3 biopsies to test HPV16 positive, have an antecedent HSIL+ cytology, or to be diagnosed as CIN3+ by the EP (P < .001 for all). p16 IHC-positive, CP-diagnosed CIN1 biopsies had lower HPV risk groups than p16 IHC-negative, CP-diagnosed CIN2 biopsies (P < .001). CONCLUSIONS.­: p16 IHC-positive, CP-diagnosed CIN2 appears to be lower cancer risk than CP-diagnosed CIN3. LAST classification of "HSIL" diagnosis, which includes p16 IHC-positive CIN2, should annotate the morphologic diagnosis (CIN2 or CIN3) to inform all management decisions, which is especially important for young (<30 years) women diagnosed with CIN2 for whom surveillance rather than treatment is recommended.