Performance of CADM1, MAL and miR124-2 methylation as triage markers for early detection of cervical cancer in self-collected and clinician-collected samples: an exploratory observational study in Papua New Guinea

Objective WHO recommends human papillomavirus (HPV) testing for cervical screening, with triage of high-risk HPV (hrHPV) positive women. However, there are limitations to effective triage for low-resource, high-burden settings, such as Papua New Guinea. In this exploratory study, we assessed the performance of host methylation as triage tools for predicting high-grade squamous intraepithelial lesions (HSIL) in self-collected and clinician-collected samples.Design Exploratory observational study.Setting Provincial hospital, same-day cervical screen-and-treat trial, Papua New Guinea.Participants 44 hrHPV+women, with paired self/clinician-collected samples (4 squamous cell carcinomas (SCC), 19 HSIL, 4 low-grade squamous intraepithelial lesions, 17 normal).Primary and secondary outcome measures Methylation levels of CADM1, MAL and miR124-2 analysed by methylation-specific PCRs against the clinical endpoint of HSIL or SCC (HSIL+) measured using liquid-based-cytology/p16-Ki67 stain.Results In clinician-collected samples, MAL and miR124-2 methylation levels were significantly higher with increasing grade of disease (p=0.0046 and p