BackgroundAssessment of DNA promoter methylation markers in cervical scrapings for the detection of cervical intraepithelial neoplasia (CIN) and cervical cancer is feasible, but finding methylation markers with both high sensitivity as well as high specificity remains a challenge. In this study, we aimed to identify new methylation markers for the detection of high-grade CIN (CIN2/3 or worse, CIN2+) by using innovative genome-wide methylation analysis (MethylCap-seq). We focused on diagnostic performance of methylation markers with high sensitivity and high specificity considering any methylation level as positive.ResultsMethylCap-seq of normal cervices and CIN2/3 revealed 176 differentially methylated regions (DMRs) comprising 164 genes. After verification and validation of the 15 best discriminating genes with methylation-specific PCR (MSP), 9 genes showed significant differential methylation in an independent cohort of normal cervices versus CIN2/3 lesions (p < 0.05). For further diagnostic evaluation, these 9 markers were tested with quantitative MSP (QMSP) in cervical scrapings from 2 cohorts: (1) cervical carcinoma versus healthy controls and (2) patients referred from population-based screening with an abnormal Pap smear in whom also HPV status was determined. Methylation levels of 8/9 genes were significantly higher in carcinoma compared to normal scrapings. For all 8 genes, methylation levels increased with the severity of the underlying histological lesion in scrapings from patients referred with an abnormal Pap smear. In addition, the diagnostic performance was investigated, using these 8 new genes and 4 genes (previously identified by our group: C13ORF18, JAM3, EPB41L3, and TERT). In a triage setting (after a positive Pap smear), sensitivity for CIN2+ of the best combination of genes (C13ORF18/JAM3/ANKRD18CP) (74 %) was comparable to hrHPV testing (79 %), while specificity was significantly higher (76 % versus 42 %, p ≤ 0.05). In addition, in hrHPV-positive scrapings, sensitivity and specificity for CIN2+ of this best-performing combination was comparable to the population referred with abnormal Pap smear.ConclusionsWe identified new CIN2/3-specific methylation markers using genome-wide DNA methylation analysis. The diagnostic performance of our new methylation panel shows higher specificity, which should result in prevention of unnecessary colposcopies for women referred with abnormal cytology. In addition, these newly found markers might be applied as a triage test in hrHPV-positive women from population-based screening. The next step before implementation in primary screening programs will be validation in population-based cohorts.Electronic supplementary materialThe online version of this article (doi:10.1186/s13148-016-0196-3) contains supplementary material, which is available to authorized users.

Background:Primary high-risk human papillomavirus (hrHPV) testing in cervical cancer screening shows relatively low specificity, which makes triage testing necessary. In this study, DNA methylation analysis was compared with cytology for triage testing in hrHPV-positive women. Moreover, feasibility of DNA methylation analysis directly on brush-based self-sampled specimens was assessed.Methods:Non-responding women from population-based screening were invited to self-collect a cervico-vaginal specimen for hrHPV testing; hrHPV-positive women were referred to a physician for triage liquid-based cytology. DNA methylation analysis was performed on 128 hrHPV-positive physician-collected triage samples and 50 matched brush self-samples with QMSP for C13ORF18, EPB41L3, JAM3 and TERT.Results:In physician-taken triage material, DNA methylation analysis of JAM3 showed the highest combined specificity (88%) and sensitivity (82%) for detection of CIN3+, whereas cytology showed a specificity of 48% and a sensitivity of 91%. Out of 39 women with abnormal cytology and normal histology (false-positive by cytology), 87% were negative for JAM3 and 90% for C13ORF18 methylation. Agreement between DNA methylation analysis performed directly on the matched self-sampled material and physician-taken samples was 88% for JAM3 (κ=0.75, P<0.001) and 90% for C13ORF18 (κ=0.77; P<0.001).Conclusions:DNA methylation analysis as a triage test in hrHPV-positive women is an attractive alternative to cytology. Furthermore, DNA methylation is feasible directly on brush-based self-samplers and showed good correlation with matched physician-taken samples. Direct molecular triage on self-collected specimens could optimise the screening program, especially for non-responders, as this would eliminate the need for an additional physician-taken scraping for triage testing.

More radical surgery in patients with (minimal) central residual disease identified by routine biopsy 8 to 10 weeks after (chemo)radiation does not improve survival and should not be recommended.