Accuracy and cost-effectiveness of cervical cancer screening by high-risk human papillomavirus DNA testing of self-collected vaginal samples

Abstract

Objective: Estimate the accuracy and cost-effectiveness of cervical cancer screening strategies based on high-risk human papillomavirus (HPV) DNA testing of self-collected vaginal samples.

Materials and methods: A subset of 1,665 women (age range, 18-50 y) participating in a cervical cancer screening study were screened by liquid-based cytology and by high-risk HPV DNA testing of both self-collected vaginal swab samples and clinician-collected cervical samples. Women with positive/abnormal screening test results and a subset of women with negative screening test results were triaged to colposcopy. On the basis of individual and combined test results, 5 screening strategies were defined. Estimates of sensitivity and specificity for cervical intraepithelial neoplasia grade 2 or worse were calculated, and a Markov model was used to estimate the incremental cost-effectiveness ratios for each strategy.

Results: Compared with cytology-based screening, high-risk HPV DNA testing of self-collected vaginal samples was more sensitive (68%, 95% CI = 58%-78% vs 85%, 95% CI = 76%-94%) but less specific (89%, 95% CI = 86%-91% vs 73%, 95% CI = 67%-79%). A strategy of high-risk HPV DNA testing of self-collected vaginal samples followed by cytology triage of HPV-positive women was comparably sensitive (75%, 95% CI = 64%-86%) and specific (88%, 95% CI = 85%-92%) to cytology-based screening. In-home self-collection for high-risk HPV DNA detection followed by in-clinic cytology triage had a slightly lower lifetime cost and a slightly higher quality-adjusted life year (QALY) expectancy than did cytology-based screening (incremental cost-effectiveness ratio of triennial screening compared with no screening was $9,871/QALY and $12,878/QALY, respectively).

Conclusions: Triennial screening by high-risk HPV DNA testing of in-home, self-collected vaginal samples followed by in-clinic cytology triage was cost-effective.

Figures

Figure 1. Attendance at colposcopy-biopsy and detection of histologically-confirmed CIN2 and ≥CIN3 among women stratified by screening test results

aISCC = invasive squamous cell carcinoma; HSIL = high grade squamous intraepithelial lesions; AGUS = atypical glandular cells of unknown significance; LSIL = low grade squamous intraepithelial lesions; ASC-US = atypical squamous cells of unknown significance; CIN = cervical intraepithelial neoplasia grade 2; ≥CIN3 = cervical intraepithelial neoplasia grade 3 or higher

Figure 2. Cost-effectiveness of different screening strategies: results of base case analysis

Note: Collection of vaginal samples is assumed to be performed by women in their homes; collection of cytology samples is assumed to be performed in a clinic setting