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

Abstract

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 selfcollected 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 5 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 (CIN21). 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 CIN21. 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.High-income nations are increasingly adopting High-Risk HPV DNA (hrHPV) testing as an adjunct to primary cytology screening, since epidemiologic studies have shown that this strategy may enhance screening effectiveness.1-8 Cervical cancer remains an important problem in Mexico despite a decades-old cytology program that in 2010 screened approximately eight million women.9 Recognizing the poor effectiveness of the Mexican cytology program, the government health insurance system for low-income citizens "Seguro Popular" recently introduced an alternative cervical cancer screening program (CCSP) based on hrHPV testing for affiliated women aged 35-64 years. The goal of the new CCSP is to achieve 85% coverage of six million women over a period of 5 years.

Triage strategies in cervical cancer detection in Mexico: methods of the FRIDA Study

“…As a result, colposcopists are unable to recognize the lesions that are not clinically visible. 28 Therefore, instead of using directed biopsies, we are collecting biopsies systematically by quadrant. Several studies support this decision by showing that the sensitivity of colposcopy could be improved by collecting more than one biopsy.…”

Population-based prevalence of cervical infection with human papillomavirus genotypes 16 and 18 and other high risk types in Tlaxcala, Mexico

“…In 2013, our study group was able to show that primary screening for hrHPV is effective, but a secondary follow-up or triage test is needed to determine which women should be sent to colposcopy [7]. We attempted to send all hrHPV positive women to colposcopy, but found it was not only inefficient, but also overburdened the local health services.…”

“…The impact of the vaccine, however, will not be seen for at least a generation, and therefore, research groups in Mexico and throughout the developing world are seeking to establish their cervical cancer screening program. At the current time, Mexican health services cannot support a screening program in which all hrHPV positive women are sent for further diagnostic work-up [7]. Indeed only a small percentage of hrHPV positive women will actually ever develop high grade cervical intraepithelial neoplasia (CIN) [8].…”

Cervical cancer screening in the era of HPV vaccination: A review of shifting paradigms in cytopathology

“…Not only do these findings demonstrate the high NPV of primary HPV screening, they also suggest the possibility that longer screening intervals in HPV negative women could be an effective and safe strategy . Other meta‐analyses and population‐based studies in China and Mexico, including large populations of women undergoing comparative primary HPV and cytology‐based screening have shown similar findings …”

“…The association between cervical cancer and human papillomavirus (HPV) is well established . The overall prevalence of high‐risk HPV (hrHPV) in the US is ∼10.5% . HPV infection is currently the most common sexually transmitted infection.…”