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