Long-term outcomes after cervical cancer screening in El Salvador: primary human papillomavirus screen-and-treat compared with cytology

Introduction From 2012 to 2017, the Cervical Cancer Prevention in El Salvador (CAPE) piloted and scaled up a human papillomavirus (HPV) screen-and-treat intervention. Findings resulted in El Salvador’s adoption of the strategy as part of the national programme, but long-term clinical outcomes are unknown. Here, we compare the detection of high-grade cervical intraepithelial neoplasia grade 2 or higher (CIN2+) and HPV infection after recommended screening intervals between two groups: women who participated in CAPE and a comparable group screened via cytology. Methods CAPE participants who had undergone screening at least 5 years previously (screen-and-treat group) and women in the same age range with conventional cytology screening 2 to 3 years previously (cytology group) were recruited for repeat screening with primary HPV testing. Women with positive HPV results were referred for colposcopy and cervical biopsy to determine further management. Women with negative HPV results received recommendations for routine future screening according to national guidelines. Results A total of 6631 women were enrolled (screen-and-treat = 4087; cytology=2544). Significantly less CIN2+ was detected in the screen-and-treat group at 0.7% (29/4087) than in the cytology group at 2.1% (54/2544) (p<0.001) with a risk ratio of 0.41 (95% CI 0.26 to 0.61). HPV positivity was also lower in the screen-and-treat group at 9.5% (388/4077) compared with the cytology group at 11.5% (293/2445) (p=0.008). Conclusion At the first round of repeat screening after the implementation of CAPE, women who underwent HPV testing in a screen-and-treat strategy had significantly less CIN2+ andHPV positivity compared with those who underwent cytology. These outcomes occurred despite a longer screening interval for HPV testing than cytology. Findings provide reassurance for women and health systems that primary HPV screen-and-treat programmes with extended screening intervals, like the one in El Salvador, are achievable and effective in low- and middle-income settings.