Reliable identification of women with CIN3+ using hrHPV genotyping and methylation markers in a cytology-screened referral population

Cervical screening aims to identify women with high-grade squamous intraepithelial lesion/cervical intraepithelial neoplasia 2-3 (HSIL/CIN2-3) or invasive cervical cancer (ICC). Identification of women with severe premalignant lesions or ICC (CIN3+) could ensure their rapid treatment and prevent overtreatment. We investigated high-risk human papillomavirus (hrHPV) detection with genotyping and methylation of FAM19A4/miR124-2 for detection of CIN3+ in 538 women attending colposcopy for abnormal cytology. All women had an additional cytology with hrHPV testing (GP5+/6+-PCR-EIA+), genotyping (HPV16/18, HPV16/18/31/45), and methylation analysis (FAM19A4/miR124-2) and at least one biopsy. CIN3+ detection was studied overall and in women <30 (n = 171) and ≥30 years (n = 367). Positivity for both rather than just one methylation markers increased in CIN3, and all ICC was positive for both. Overall sensitivity and specificity for CIN3+ were, respectively, 90.3% (95%CI 81.3–95.2) and 31.8% (95%CI 27.7–36.1) for hrHPV, 77.8% (95%CI 66.9–85.8) and 69.3% (95%CI 65.0–73.3) for methylation biomarkers and 93.1% (95%CI 84.8–97.0) and 49.4% (95%CI 44.8–53.9) for combined HPV16/18 and/or methylation positivity. For CIN3, hrHPV was found in 90.9% (95%CI 81.6–95.8), methylation positivity in 75.8% (95%CI 64.2–84.5) and HPV16/18 and/or methylation positivity in 92.4% (95%CI 83.5–96.7). In women aged ≥30, the sensitivity of combined HPV16/18 and methylation was increased (98.2%, 95%CI 90.6–99.7) with a specificity of 46.3% (95%CI 40.8–51.9). Combination of HPV16/18 and methylation analysis was very sensitive and offered improved specificity for CIN3+, opening the possibility of rapid treatment for these women and follow-up for women with potentially regressive, less advanced, HSIL/CIN2 lesions.     

Cervical cancer risk in HPV‐positive women after a negative FAM19A4/mir124‐2 methylation test: A post hoc analysis in the POBASCAM trial with 14 year follow‐up

DNA methylation analysis of cervical scrapes using FAM19A4 and mir124‐2 genes has shown a good clinical performance in detecting cervical cancer and advanced CIN lesions in need of treatment in HPV‐positive women. To date, longitudinal data on the cancer risk of methylation test‐negative women are lacking. In our study, we assessed the longitudinal outcome of FAM19A4/mir124‐2 methylation analysis in an HPV‐positive screening cohort with 14 years of follow‐up. Archived HPV‐positive cervical scrapes of 1,040 women (age 29–61 years), who were enrolled in the POBASCAM screening trial (ISRCTN20781131) were tested for FAM19A4/mir124‐2 methylation. By linkage with the nationwide network and registry of histo‐ and cytopathology in the Netherlands (PALGA), 35 cervical cancers were identified during 14 years of follow‐up comprising three screens (baseline, and after 5 and 10 years). The baseline scrape of 36.1% (n = 375) women tested positive for FAM19A4/mir124‐2 methylation, including 24 women with cervical cancer in follow‐up, and 30.6% (n = 318) had abnormal cytology (threshold borderline dyskaryosis or ASCUS), including 14 women with cervical cancer in follow‐up. Within screening round capability of FAM19A4/mir124‐2 methylation to detect cervical cancer was 100% (11/11, 95% CI: 71.5–100). Kaplan–Meier estimate of 14‐year cumulative cervical cancer incidence was 1.7% (95% CI: 0.66–3.0) among baseline methylation‐negative and 2.4% (95% CI: 1.4–3.6) among baseline cytology‐negative women (risk difference: 0.71% [95% CI: 0.16–1.4]). In conclusion, a negative FAM19A4/mir124‐2 methylation test provides a low cervical cancer risk in HPV‐positive women of 30 years and older. FAM19A4/mir124‐2 methylation testing merits consideration as an objective triage test in HPV‐based cervical screening programs.     

CADM1 and MAL promoter methylation levels in hrHPV‐positive cervical scrapes increase proportional to degree and duration of underlying cervical disease

Combined detection of cell adhesion molecule 1 (CADM1) and T‐lymphocyte maturation‐associated protein (MAL) promoter methylation in cervical scrapes is a promising triage strategy for high‐risk human papillomavirus (hrHPV)‐positive women. Here, CADM1 and MAL DNA methylation levels were analysed in cervical scrapes of hrHPV‐positive women with no underlying high‐grade disease, high‐grade cervical intraepithelial neoplasia (CIN) and cervical cancer. CADM1 and MAL methylation levels in scrapes were first related to CIN‐grade of the corresponding biopsy and second to CIN‐grade stratified by the presence of ‘normal’ or ‘abnormal’ cytology as present in the accompanying scrape preceding the cervical biopsy. The scrapes included 167 women with ≤CIN1, 54 with CIN2/3 and 44 with carcinoma. In a separate series of hrHPV‐positive scrapes of women with CIN2/3 (n = 48), methylation levels were related to duration of preceding hrHPV infection (PHI; <5 and ≥5 years). Methylation levels were determined by quantitative methylation‐specific PCR and normal cytology scrapes of hrHPV‐positive women with histologically ≤CIN1 served as reference. CADM1 and MAL methylation levels increased proportional to severity of the underlying lesion, showing an increase of 5.3‐ and 6.2‐fold in CIN2/3, respectively, and 143.5‐ and 454.9‐fold in carcinomas, respectively, compared to the reference. Methylation levels were also elevated in CIN2/3 with a longer duration of PHI (i.e. 11.5‐ and 13.6‐fold, respectively). Moreover, per histological category, methylation levels were higher in accompanying scrapes with abnormal cytology than in scrapes with normal cytology. Concluding, CADM1 and MAL promoter methylation levels in hrHPV‐positive cervical scrapes are related to the degree and duration of underlying cervical disease and markedly increased in cervical cancer.     

The clinical value of HPV genotyping in triage of women with high‐risk‐HPV‐positive self‐samples

Cytology alone, or combined with HPV16/18 genotyping, might be an acceptable method for triage in hrHPV‐cervical cancer screening. Previously studied HPV‐genotype based triage algorithms are based on cytology performed without knowledge of hrHPV status. The aim of this study was to explore the value of hrHPV genotyping combined with cytology as triage tool for hrHPV‐positive women. 520 hrHPV‐positive women were included from a randomised controlled self‐sampling trial on screening non‐attendees (PROHTECT‐3B). Eighteen baseline triage strategies were evaluated for cytology and hrHPV genotyping (Roche Cobas 4800) on physician‐sampled triage material. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), referral rate, and number of referrals needed to diagnose (NRND) were calculated for CIN2+ and CIN3+. A triage strategy was considered acceptable if the NPV for CIN3+ was ≥98%, combined with maintenance or improvement of sensitivity and an increase in specificity in reference to the comparator, being cytology with a threshold of atypical cells of undetermined significance (ASC‐US). Three triage strategies met the criteria: HPV16+ and/or ≥LSIL; HPV16+ and/or ≥HSIL; (HPV16+ and/or HPV18+) and/or ≥HSIL. Combining HPV16+ and/or ≥HSIL yielded the highest specificity (74.9%, 95% CI 70.5–78.9), with a sensitivity (94.4%, 95% CI 89.0–97.7) similar to the comparator (93.5%, 95% CI 87.7–97.1), and a decrease in referral rate from 52.2% to 39.5%. In case of prior knowledge of hrHPV presence, triage by cytology testing can be improved by adjusting its threshold, and combining it with HPV16/18 genotyping. These strategies improve the referral rate and specificity for detecting CIN3+ lesions, while maintaining adequate sensitivity.     

Methylation testing for the detection of recurrent cervical intraepithelial neoplasia

Women treated for CIN2/3 remain at increased risk of recurrent CIN and cervical cancer, and therefore posttreatment surveillance is recommended. This post hoc analysis evaluates the potential of methylation markers ASCL1/LHX8 and FAM19A4/miR124-2 for posttreatment detection of recurrent CIN2/3. Cervical scrapes taken at 6 and 12 months posttreatment of 364 women treated for CIN2/3 were tested for methylation of ASCL1/LHX8 and FAM19A4/miR124-2 using quantitative multiplex methylation-specific PCR. Performance of the methylation tests were calculated and compared with the performance of HPV and/or cytology. Methylation levels of recurrent CIN were compared between women with a persistent HPV infection, and women with an incident HPV infection or without HPV infection. Recurrent CIN2/3 was detected in 42 women (11.5%), including 28 women with CIN2 and 14 with CIN3. ASCL1/LHX8 tested positive in 13/14 (92.9%) of recurrent CIN3 and 13/27 (48.1%) of recurrent CIN2. FAM19A4/miR124-2 tested positive in 14/14 (100%) of recurrent CIN3 and 10/27 (37.0%) of recurrent CIN2. Combined HPV and/or methylation testing showed similar positivity rates as HPV and/or cytology. The CIN2/3 risk at 12 months posttreatment was 30.8% after a positive ASCL1/LHX8 result at 6 months posttreatment. Methylation levels of CIN2/3 in women with a persistent HPV infection were significantly higher compared with women with an incident or no HPV infection. In conclusion, posttreatment monitoring by methylation analysis of ASCL1/LHX8 and FAM19A4/miR124-2 showed a good performance for the detection of recurrent CIN. DNA methylation testing can help to identify women with recurrent CIN that require re-treatment.     

Long‐term risk of cervical intraepithelial neoplasia grade 3 or worse according to high‐risk human papillomavirus genotype and semi‐quantitative viral load among 33,288 women with normal cervical cytology

In this prospective cohort study, we estimated the long‐term risk of cervical intraepithelial neoplasia grade 3 or cancer (CIN3+) by high‐risk human papillomavirus (hrHPV) genotype and semi‐quantitative viral load at baseline among 33,288 women aged 14–90 years with normal baseline cytology. During 2002–2005, residual liquid‐based cervical cytology samples were collected from women screened for cervical cancer in Copenhagen, Denmark. Samples were HPV‐tested with Hybrid Capture 2 (HC2) and genotyped with INNO‐LiPA. Semi‐quantitative viral load was measured by HC2 relative light units in women with single hrHPV infections. The cohort was followed in a nationwide pathology register for up to 11.5 years. In women aged ≥30 years at baseline, the 8‐year absolute risk for CIN3+ following baseline detection of HPV16 was 21.8% (95% confidence interval [CI]: 18.0–25.6%). The corresponding risks for HPV18, HPV31, HPV33, and other hrHPV types, respectively, were 12.8% (95% CI: 7.6–18.0%), 11.3% (95% CI: 7.7–14.9%), 12.9% (95% CI: 7.0–18.8%) and 3.9% (95% CI: 2.7–5.2%). Similar absolute risk estimates were observed in women aged <30 years. Higher HPV16‐viral load was associated with increased risk of CIN3+ (hazard ratio = 1.34, 95% CI: 1.10–1.64, per 10‐fold increase in viral load). A similar trend, although statistically nonsignificant, was found for viral load of HPV18. The 8‐year absolute risk of CIN3+ in women with HPV16‐viral load ≥100.0 pg/ml was 30.2% (95% CI: 21.9–38.6%). Our results support that hrHPV genotyping during cervical cancer screening may help identify women at highest risk of CIN3+.     

Validation of a DNA methylation HPV triage classifier in a screening sample

High‐risk human papillomavirus (hrHPV) DNA tests have excellent sensitivity for detection of cervical intraepithelial neoplasia 2 or higher (CIN2+). A drawback of hrHPV screening, however, is modest specificity. Therefore, hrHPV‐positive women might need triage to reduce adverse events and costs associated with unnecessary colposcopy. We compared the performance of HPV16/18 genotyping with a predefined DNA methylation triage test (S5) based on target regions of the human gene EPB41L3, and viral late gene regions of HPV16, HPV18, HPV31 and HPV33. Assays were run using exfoliated cervical specimens from 710 women attending routine screening, of whom 38 were diagnosed with CIN2+ within a year after triage to colposcopy based on cytology and 341 were hrHPV positive. Sensitivity and specificity of the investigated triage methods were compared by McNemar's test. At the predefined cutoff, S5 showed better sensitivity than HPV16/18 genotyping (74% vs 54%, P = 0.04) in identifying CIN2+ in hrHPV‐positive women, and similar specificity (65% vs 71%, P = 0.07). When the S5 cutoff was altered to allow equal sensitivity to that of genotyping, a significantly higher specificity of 91% was reached (P < 0.0001). Thus, a DNA methylation test for the triage of hrHPV‐positive women on original screening specimens might be a valid approach with better performance than genotyping.     

Specimen self‐collection and HPV DNA screening in a pilot study of 100,242 women

Since cervical cancer remains common in Mexico despite an established cytology screening program, the Ministry of Health recently introduced pilot front‐line HPV testing into the Mexican cervical cancer screening program (CCSP). Here, we present the key field performance metrics of this population‐based study. High‐risk HPV DNA (hrHPV) testing was conducted on self‐collected vaginal specimens from 100,242 women aged 25–75 years residing in Morelos State. All hrHPV positive women and a random sample of 3.2% (n = 2,864) of hrHPV negative participants were referred for colposcopic examination. The main disease endpoint of interest was cervical intraepithelial neoplasia grade 2 or higher (CIN2+). We calculated relative risk, positive predictive value and negative predictive value adjusted for screening test verification bias. The overall prevalence of hrHPV was 10.8% (95%CI 10.6–11.0). Women positive for hrHPV had a relative risk of 15.7 for histologically detectable CIN2+. The adjusted positive predictive value of the hrHPV test was 2.4% (95%CI 2.1–2.7); whereas the adjusted negative predictive value was 99.8% (95%CI 99.8–99.9). These findings suggest that large‐scale vaginal hrHPV testing in a middle‐income country can identify women at greater risk of advanced cervical abnormalities in a programmatically meaningful way but care is warranted to ensure that disease not detectable at colposcopy is kept to a minimum. PASS shows areas that need improvement and sets the stage for wider use of hrHPV screening of self‐collected vaginal specimens in Mexico.     

FAM19A4/miR124-2 methylation in invasive cervical cancer: A retrospective cross-sectional worldwide study

Widespread adoption of primary human papillomavirus (HPV)-based screening has encouraged the search for a triage test which retains high sensitivity for the detection of cervical cancer and precancer, but increases specificity to avoid overtreatment. Methylation analysis of FAM19A4 and miR124-2 genes has shown promise for the triage of high-risk (hr) HPV-positive women. In our study, we assessed the consistency of FAM19A4/miR124-2 methylation analysis in the detection of cervical cancer in a series of 519 invasive cervical carcinomas (n = 314 cervical scrapes, n = 205 tissue specimens) from over 25 countries, using a quantitative methylation-specific PCR (qMSP)-based assay (QIAsure Methylation Test®). Positivity rates stratified per histotype, FIGO stage, hrHPV status, hrHPV genotype, sample type and geographical region were calculated. In total, 510 of the 519 cervical carcinomas (98.3%; 95% CI: 96.7–99.2) tested FAM19A4/miR124-2 methylation-positive. Test positivity was consistent across the different subgroups based on cervical cancer histotype, FIGO stage, hrHPV status, hrHPV genotype, sample type and geographical region. In conclusion, FAM19A4/miR124-2 methylation analysis detects nearly all cervical carcinomas, including rare histotypes and hrHPV-negative carcinomas. These results indicate that a negative FAM19A4/miR124-2 methylation assay result is likely to rule out the presence of cervical cancer.     

Comparative performance of novel self‐sampling methods in detecting high‐risk human papillomavirus in 30,130 women not attending cervical screening

We determined whether the participation rate for a brush‐based cervicovaginal self‐sampling device is noninferior to the participation rate for a lavage‐based one for testing for hrHPV (high‐risk human papillomavirus). Additionally, positivity rates for hrHPV, the detection rates for cervical intraepithelial neoplasia grades 2 and 3 or worse (CIN2+/3+), and user comfort were compared. A total of 35,477 non‐responders of the regular cervical screening program aged 33–63 years were invited to participate. Eligible women (n = 30,130) were randomly assigned to receive either a brush‐based or a lavage‐based device, and a questionnaire for reporting user convenience. Self‐sampling responders testing hrHPV‐positive were invited for a physician‐taken sample for cytology; triage‐positive women were referred for colposcopy. A total of 5,218 women participated in the brush‐based sampling group (34.6%) and 4809 women in the lavage‐based group (31.9%), i.e. an absolute difference of 2.7% (95%CI 1.8–4.2). The hrHPV‐positivity rates in the two groups were identical (8.3%, relative risk (RR) 0.99, 95%CI 0.87–1.13). The detection of CIN2+ and CIN3+ in the brush group (2.0% for CIN2+; 1.3% for CIN3+) was similar to that in the lavage group (1.9% for CIN2+; 1.0% for CIN3+) with a cumulative RR of 1.01, 95%CI 0.83–1.24 for CIN2+ and 1.25, 95%CI 0.92–1.70 for CIN3+. The two self‐sampling devices performed similarly in user comfort. In conclusion, offering a brush‐based device to non‐responders is noninferior to offering a lavage‐based device in terms of participation. The two self‐sampling methods are equally effective in detecting hrHPV, CIN2+/CIN3+ and are both well accepted.     

Good performance of p16/ki‐67 dual‐stained cytology for surveillance of women treated for high‐grade CIN

Women treated for high‐grade cervical intraepithelial neoplasia (CIN) are at risk of recurrent CIN Grade 2 or worse (rCIN2+). Currently, posttreatment monitoring is performed using cytology or cytology/high‐risk (hr)HPV cotesting. This study aimed to evaluate the performance of p16/Ki‐67 dual‐stained cytology (p16/Ki‐67) for posttreatment monitoring. Three hundred and twenty‐three women treated for high‐grade CIN in the SIMONATH study underwent close surveillance by cytology, hrHPV and DNA methylation marker testing up to 12 months posttreatment. Histological endpoints were ascertained by colposcopy with biopsy at 6 and/or 12 months. p16/Ki‐67 dual‐staining was performed on residual liquid‐based cytology samples obtained at, or shortly before biopsy collection. Clinical performance estimates of cytology, hrHPV, p16/Ki‐67 testing and combinations thereof for the detection of rCIN2+ were determined and compared to each other. Sensitivity of p16/Ki‐67 for rCIN2+ (69.2%) was nonsignificantly lower than that of cytology (82.1%; ratio 0.84, 95% CI: 0.71–1.01), but significantly lower than that of hrHPV testing (84.6%; ratio 0.82, 95% CI: 0.68–0.99). Specificity of p16/Ki‐67 for rCIN2+ (90.4%) was significantly higher compared to both cytology (70.8%; ratio 1.28, 95% CI: 1.19–1.37) and hrHPV testing (76.2%; ratio 1.19, 95% CI: 1.12–1.26). Overall, hrHPV testing showed very high sensitivity, along with a good specificity. When considering cotesting, combined p16/Ki‐67/hrHPV testing showed rCIN2+ sensitivity comparable to cytology/hrHPV cotesting (87.2% vs. 89.7%; ratio 0.97, 95% CI: 0.92–1.03), but with significantly increased specificity (74.2% vs. 58.1%; ratio 1.28, 95% CI: 1.19–1.38). Thus, when considered in combination with hrHPV, p16/Ki‐67 might be an attractive approach for surveillance of women treated for high‐grade CIN.     

HPV for cervical cancer screening (HPV FOCAL): Complete Round 1 results of a randomized trial comparing HPV‐based primary screening to liquid‐based cytology for cervical cancer

Complete Round 1 data (baseline and 12‐month follow‐up) for HPV FOCAL, a randomized trial establishing the efficacy of HPV DNA testing with cytology triage as a primary screen for cervical cancer are presented. Women were randomized to one of three arms: Control arm – Baseline liquid‐based cytology (LBC) with ASCUS results triaged with HPV testing; Intervention and Safety arms – Baseline HPV with LBC triage for HPV positives. Results are presented for 15,744 women allocated to the HPV (intervention and safety combined) and 9,408 to the control arms. For all age cohorts, the CIN3+ detection rate was higher in the HPV (7.5/1,000; 95%CI: 6.2, 8.9) compared to the control arm (4.6/1,000; 95%CI: 3.4, 6.2). The CIN2+ detection rates were also significantly higher in the HPV (16.5/1,000; 95%CI: 14.6, 18.6) vs. the control arm (10.1/1,000; 95%CI: 8.3, 12.4). In women ≥35 years, the overall detection rates for CIN2+ and CIN3+ were higher in the HPV vs. the control arm (CIN2+:10.0/1,000 vs. 5.2/1,000; CIN3+: 4.2/1,000 vs. 2.2/1,000 respectively, with a statistically significant difference for CIN2+). HPV testing detected significantly more CIN2+ in women 25–29 compared to LBC (63.7/1,000; 95%CI: 51.9, 78.0 vs. 32.4/1,000; 95%CI: 22.3, 46.8). HPV testing resulted in significantly higher colposcopy referral rates for all age cohorts (HPV: 58.9/1,000; 95%CI: 55.4, 62.7 vs. control: 30.9/1,000; 95%CI: 27.6, 34.6). At completion of Round 1 HPV‐based cervical cancer screening in a population‐based program resulted in greater CIN2+ detection of across all age cohorts compared to LBC screening.     

DNA methylation of imprinted gene control regions in the regression of low‐grade cervical lesions

The role of host epigenetic mechanisms in the natural history of low‐grade cervical intraepithelial neoplasia (CIN1) is not well characterized. We explored differential methylation of imprinted gene regulatory regions as predictors of the risk of CIN1 regression. A total of 164 patients with CIN1 were recruited from 10 Duke University clinics for the CIN Cohort Study. Participants had colposcopies at enrollment and up to five follow‐up visits over 3 years. DNA was extracted from exfoliated cervical cells for methylation quantitation at CpG (cytosine‐phosphate‐guanine) sites and human papillomavirus (HPV) genotyping. Hazard ratios (HR) and 95% confidence intervals (CI) were estimated using Cox regression to quantify the effect of methylation on CIN1 regression over two consecutive visits, compared to non‐regression (persistent CIN1; progression to CIN2+; or CIN1 regression at a single time‐point), adjusting for age, race, high‐risk HPV (hrHPV), parity, oral contraceptive and smoking status. Median participant age was 26.6 years (range: 21.0–64.4 years), 39% were African‐American, and 11% were current smokers. Most participants were hrHPV‐positive at enrollment (80.5%). Over one‐third of cases regressed (n = 53, 35.1%). Median time‐to‐regression was 12.6 months (range: 4.5–24.0 months). Probability of CIN1 regression was negatively correlated with methylation at IGF2AS CpG 5 (HR = 0.41; 95% CI = 0.23–0.77) and PEG10 DMR (HR = 0.80; 95% CI = 0.65–0.98). Altered methylation of imprinted IGF2AS and PEG10 DMRs may play a role in the natural history of CIN1. If confirmed in larger studies, further research on imprinted gene DMR methylation is warranted to determine its efficacy as a biomarker for cervical cancer screening.     

High‐risk human papillomavirus DNA load in a population‐based cervical screening cohort in relation to the detection of high‐grade cervical intraepithelial neoplasia and cervical cancer

In a population‐based cervical screening cohort, we determined the value of type‐specific viral load assessment for the detection of high‐grade cervical intraepithelial neoplasia and cervical cancer (≥CIN2). Viral load was determined by type‐specific real‐time PCR in women with single HPV16,‐18,‐31 and ‐33 infections, as determined by GP5+/6+‐PCR. Study endpoints were the detection of cumulative ≥CIN2 or ≥CIN3 within 18 months of follow‐up. High viral loads of HPV16,‐31, and ‐33 were predictive for ≥CIN2 (relative risk of 1.6 (95% CI: 1.3–1.9), 1.7 (95% CI: 1.1–2.7) and 1.9 (95% CI: 1.1–3.1) per 10‐fold change in viral load, respectively). For HPV18, the relative risk was of similar magnitude (1.5, 95% CI: 0.7–3.1), though not significant (p = 0.3). Subsequently, we determined the sensitivities of viral load for ≥CIN2 and ≥CIN3 in HPV DNA‐positive women using viral load thresholds previously defined in a cross‐sectional study. These thresholds were based on the 25th, 33rd and 50th percentiles of type‐specific HPV16,‐18,‐31 or ‐33 viral load values found in women with normal cytology. For all types, combined sensitivities for ≥CIN2 were 93.5%, 88.8% and 77.7% for the 25th, 33rd and 50th percentile thresholds, respectively. Response‐operator‐characteristics (ROC) curve analysis showed that viral load testing on HPV DNA‐positive women in addition to or instead of cytology may result in an increased sensitivity for ≥CIN2, but at the cost of a marked decrease in specificity in relation to cytology. Similar results were obtained when using ≥CIN3 as endpoint. In conclusion, in a cervical screening setting viral load assessment of HPV16, 18, 31 and 33 has no additive value to stratify high‐risk HPV GP5+/6+‐PCR‐positive women for risk of ≥CIN2 or ≥CIN3. © 2008 Wiley‐Liss, Inc.     

Stratifying HPV‐positive women for CIN3+ risk after one and two rounds of HPV‐based screening

A main challenge of human papilloma (HPV)‐based screening for cervical cancer is to adequately identify HPV‐positive women at highest risk of cervical intraepithelial neoplasia grade 3 or worse, CIN3+. The prognostic value of currently used adjunct markers (HPV16/18 genotyping and reflex cytology) may change after multiple rounds of HPV‐based screening because of a change in the proportion of HPV‐positive women with incident infections. To this end, we re‐analyzed results from the POBASCAM trial (Population Based Screening Study Amsterdam). Women were randomized to HPV/cytology cotesting (intervention group) or to cytology‐only (HPV blinded; control group) at enrolment. Our analytical population consisted of women with an HPV‐positive result at the second round, 5 years after enrolment (n = 381 intervention, n = 392 control). Nine‐year CIN3+ risks were estimated by Kaplan–Meier. HPV‐positive women were stratified by risk markers: HPV16/18 genotyping, reflex cytology and preceding HPV results. When comparing one to two rounds of HPV‐based screening, the prognostic value of an abnormal cytology result did not change (40.0% vs. 42.3%, p = 0.5617), but diminished for an HPV16/18 positive result (25.4% vs. 38.0%, p = 0.0132). HPV16/18 genotyping was nondiscriminative in women with incident HPV infections (HPV16/18 positive 10.0% vs. negative 12.1%, p = 0.3193). Women from the intervention group were more likely to have incident infections compared to women from the control group (incident screen‐positive results 75.6% vs. 64.6%, p = 0.001) Our results indicate that at a second round of HPV‐based screening, risk differentiation by cytology remained strong, but was diminished for HPV 16/18 genotyping because of a larger proportion of incident infections.     

Prevalence of types 16 and 33 is increased in high-risk human papillomavirus positive women with cervical intraepithelial neoplasia grade 2 or worse

High-risk human papillomavirus (hrHPV) types are causally related to cervical cancer and its high-grade precursor lesions. The risk posed by the different hrHPV types for the development of cervical intraepithelial neoplasia grade 2 or worse (> or =CIN2) needs to be established. Here, we present the hrHPV type-distribution in relation to cytology and histology for women participating in a cervical screening program. From 44,102 women who participated in a population-based cervical screening program in the Netherlands, 2,154 hrHPV GP5+/6+ PCR positive women were recruited to determine the distribution of 14 hrHPV types by reverse line blotting of GP5+/6+ PCR products. For each HPV type, associations with cytology and histologically confirmed > or =CIN2 were measured by odds ratios. HPV types 16 and 33 were more prevalent in women, amongst those containing a single hrHPV type, with moderate dyskaryosis or worse (>BMD) than in women with normal cytology, but only in case of underlying > or =CIN2 (OR 4.10, 95%CI 2.98-5.64 and OR 2.68, 95%CI 1.39-5.15, respectively). Similar results were obtained for women with double infections (OR 3.29, 95% CI 1.61-6.75 and OR 4.37, 95% CI 1.17-16.34). Coexisting types did not influence the prevalence of > or =CIN2 in HPV 16 or 33 positive women. The increased prevalence of type 16 and 33 in hrHPV positive women with > or =CIN2, compared to women with normal cytology, suggests that infection with these types confers an increased risk for development of > or =CIN2. Distinguishing these types may therefore have implications for future cervical screening strategies.     

Incidence and outcome of acquisition of human papillomavirus infection in women with normal cytology—A population‐based cohort study from Taiwan

Little is known about acquisition of human papillomavirus (HPV) and its outcome among older women with negative HPV testing and normal cytology. A longitudinal 3‐yr follow‐up of nested‐cohort subjects (n = 8825) from a population‐based cervical cancer screening study whose Pap and HPV tests were negative at baseline were conducted. Every active HPV‐negative (n = 413) participant had 12‐mo follow‐ups of Pap smear and HPV testing. Colposcopy was performed if either HPV‐positive or cytology was abnormal. The cytology and histology information of the remaining subjects (passive HPV‐negative, n = 8412) was obtained from national registry database. Median age of participants was 45 yr (range, 30–73 yr). The incidence of new acquisition was 4.2/100 woman‐years. The 3‐yr cumulative total HPV acquisition rate was 11.1% (95% confidence interval [CI]: 8.1–14.1). Increased number of sexual partners (≥2 vs. 1) of the participant was associated with risk of acquisition (odds ratio [OR]: 5.0, 95% CI: 2.0–12.6) by multivariate analysis. Three cases of ≥ cervical intraepithelial neoplasia (CIN) 2 were identified in 3‐yr follow‐up in active HPV‐negative subjects. HPV genotypes in the dysplastic tissue were actually present at baseline samples after reanalysis. From the passive HPV‐negative group, only 1 case progressed to CIN2 probably after HPV acquisition. Negative Pap and HPV tests assured a very low risk of developing ≥ CIN2 within 3 yr despite incident HPV infection.     

A DNA methylation classifier of cervical precancer based on human papillomavirus and human genes

Testing for high‐risk (hr) types of human papillomavirus (HPV) is highly sensitive as a screening test of high‐grade cervical intraepithelial neoplastic (CIN2/3) disease, the precursor of cervical cancer. However, it has a relatively low specificity. Our objective was to develop a prediction rule with a higher specificity, using combinations of human and HPV DNA methylation. Exfoliated cervical specimens from colposcopy‐referral cohorts in London were analyzed for DNA methylation levels by pyrosequencing in the L1 and L2 regions of HPV16, HPV18, HPV31 and human genes EPB41L3, DPYS and MAL. Samples from 1,493 hrHPV‐positive women were assessed and of these 556 were found to have CIN2/3 at biopsy; 556 tested positive for HPV16 (323 CIN2/3), 201 for HPV18 (73 CIN2/3) and 202 for HPV31 (98 CIN2/3). The prediction rule included EPB41L3 and HPV and had area under curve 0.80 (95% CI 0.78–0.82). For 90% sensitivity, specificity was 36% (33–40) and positive predictive value (PPV) was 46% (43–48). By HPV type, 90% sensitivity corresponded to the following specificities and PPV, respectively: HPV16, 38% (32–45) and 67% (63–71); HPV18, 53% (45–62) and 52% (45–59); HPV31, 39% (31–49) and 58% (51–65); HPV16, 18 or 31, 44% (40–49) and 62% (59–65) and other hrHPV 17% (14–21) and 21% (18–24). We conclude that a methylation assay in hrHPV‐positive women might improve PPV with minimal sensitivity loss.     

Methylation marker analysis of self‐sampled cervico‐vaginal lavage specimens to triage high‐risk HPV‐positive women for colposcopy

Methylation markers were studied for their suitability to triage human papillomavirus (HPV)‐positive women by testing self‐collected cervico‐vaginal lavage specimens. For this purpose, we analyzed 355 hrHPV‐positive self‐collected specimens with three methylation markers, that is, CADM1‐m18, MAL‐m1 and miR‐124‐2 by quantitative methylation‐specific PCR. The areas under the receiver‐operating characteristic (ROC) curve for end‐point cervical intraepithelial neoplasia grade 3 or worse (CIN3+) were 0.637 for CADM1‐m18, 0.767 for MAL‐m1 and 0.762 for miR‐124‐2. This indicates that CADM1‐m18 is not suitable as single marker. By varying the thresholds of both markers in the bi‐marker panels CADM1‐m18/MAL‐m1, CADM1‐m18/miR‐124‐2 and MAL‐m1/miR‐124‐2 upper and lower ROC curves were obtained, depicting the maximum and minimum CIN3+ sensitivity, respectively, at given specificity. For all these bi‐marker combinations, the upper curves were similar. However, for the MAL‐m1/miR‐124‐2 panel, the distance between upper and lower ROC curves was closest and this panel displayed the highest assay thresholds, indicating that this combination was most robust. At clinical specificities of 50 and 70%, the MAL‐m1/miR‐124‐2 sensitivity for detection of CIN3+ ranged from 77.0 to 87.8% and from 64.9 to 71.6%, respectively. At 70% specificity thresholds no carcinomas were missed. By comparison, the CIN3+ sensitivity of HPV16/18 genotyping on the self‐sampled lavage specimens was 58.1% (95%CI: 46.6–68.8) at a specificity of 87.7% (95%CI: 83.2–91.2). In conclusion, methylation analysis is a promising triage tool that in combination with HPV‐DNA testing offers feasible, full molecular screening on self‐collected cervico‐vaginal lavage specimens.     

Triaging HPV‐positive women with normal cytology by p16/Ki‐67 dual‐stained cytology testing: Baseline and longitudinal data

Primary human papillomavirus (HPV)‐based screening results in a 2–5% lower specificity for cervical intraepithelial neoplasia Grade 2 or worse (CIN2+) compared to Pap cytology. To identify HPV‐positive women with CIN2+, we retrospectively evaluated the cross‐sectional and longitudinal performance of p16/Ki‐67 dual‐stained cytology in HPV‐positive women with normal cytology participating in population‐based cervical screening. Conventional Pap cytology specimens of 847 of these women derived from the VUSA‐Screen study were dual‐stained for p16/Ki‐67. Cross‐sectional clinical performance in detecting CIN3 or worse (CIN3+), and CIN2+ was compared to that of baseline HPV genotyping. Moreover, 5‐year cumulative incidence risks (CIR) for CIN3+ (CIN2+) were determined. The sensitivity of p16/Ki‐67 dual‐stained cytology for CIN3+ (CIN2+) was 73.3% (68.8%) with a specificity of 70.0% (72.8%). HPV16/18 genotyping showed a sensitivity for CIN3+ (CIN2+) of 46.7% (43.8%), with a specificity of 78.3% (79.4%). The 5‐year CIR for CIN3+ in HPV‐positive women with normal cytology was 6.9%. Testing these women with p16/Ki‐67 dual‐stained cytology resulted in a significantly lower CIN3+ 5‐year CIR of 3.3% (p = 0.017) in case of a negative test result. A negative HPV16/18 genotyping test result also led to a lower 5‐year CIN3+ CIR of 3.6%. p16/Ki‐67 dual‐stained cytology detects more than 70% of underlying CIN3+ lesions in HPV‐positive women with normal cytology at baseline and is therefore suitable for triaging these women to colposcopy. Furthermore, the CIN3+ 5‐year CIR of 3.3% after a negative dual‐stain result is significantly lower compared to the 5‐year CIR of 6.9% in women without p16/Ki‐67 dual‐stained cytology triage.