Performance of visual inspection of the cervix with acetic acid (VIA) for triage of HPV screen-positive women: results from the ESTAMPA study

Abstract

VIA is recommended for triage of HPV-positive women attending cervical screening. In the multicentric ESTAMPA study, VIA performance for detection of cervical intraepithelial neoplasia grade 3 or worse (CIN3+) among HPV-positive women was evaluated. Women aged 30-64 years were screened with HPV testing and cytology and referred to colposcopy if either test was positive. At colposcopy visit, study-trained midwives/nurses/GPs performed VIA ahead of colposcopy. VIA was considered positive if acetowhite lesions were observed in or close to the transformation zone. Ablative treatment eligibility was assessed for VIA positives. Performance indicators were estimated. Three thousand one hundred and forty-two HPV-positive women were included. Sensitivity for CIN3+ was 85.9% (95% CI 81.2-89.5) among women <50 years and, although not significant, slightly lower in women 50+ (78.0%, 95% CI 65.9-86.6). Overall specificity was 58.6% (95% CI 56.7-60.5) and was significantly higher among women 50+ (70.3%, 95% CI 66.8-73.5) compared to women <50 (54.3%, 95% CI 52.1-56.5). VIA positivity was lower among women 50+ (35.2%, 95% CI 31.9-38.6) compared to women <50 (53.2, 95% CI 51.1-55.2). Overall eligibility for ablative treatment was 74.5% and did not differ by age. VIA sensitivity, specificity, and positivity, and ablative treatment eligibility varied highly by provider (ranges: 25%-95.4%, 44.9%-94.4%, 8.2%-65.3%, 0%-98.7%, respectively). VIA sensitivity for cervical precancer detection among HPV-positive women performed by trained providers was high with an important reduction in referral rates. However, scaling-up HPV screening triaged by VIA will be challenging due to the high variability of VIA performance and providers' need for training and supervision.

Trial registration: ClinicalTrials.gov NCT01881659.

Keywords: ESTAMPA; HPV; ablative treatment eligibility; cervical cancer screening and triage; visual inspection with acetic acid.

FIGURE 1

Study population. ESTAMPA included participants recruited between December 2012 and December 2021. Ninety‐eight percent of VIAs were performed by 8 examiners (1 GP in Bolivia and Honduras each, 1 midwife in Peru, and 5 nurses elsewhere); examiners who performed less than 50 VIAs were grouped into a single category for analyses. In total 3142 women were included in the analyses of whom 557 (18%) had CIN2+ and 2585 (82%) were considered without cervical disease (

FIGURE 2

VIA results according to age in HPV‐positive women within the ESTAMPA study

FIGURE 3

Transformation zone (TZ) type by age and eligibility for ablative treatment among women with positive VIA

FIGURE 4

Sensitivity and specificity of VIA for detection of precancerous cervical lesions (A), and eligibility for ablative treatment of VIA positives and VIA positivity (B) among HPV positive women by VIA examiner. E9 groups examiners who performed less than 50 VIAs. Dashed lines: overall sensitivity (84.5%) and specificity (58.6%), and, overall eligibility rate (74.5%) and VIA positivity (48.6%), respectively. Sensitivity range: 25.0%‐95.4%. Specificity range: 44.9%‐94.4%. Eligibility rate range: 0%‐98.7%. VIA positivity range: 8.2%‐65.3%. Circles' sizes are proportional to the number of VIAs performed by examiner.