Evaluation of self-collected vaginal specimens for the detection of high-risk human papillomavirus infection and the prediction of high-grade cervical intraepithelial lesions in a high-burden, low-resource setting

OBJECTIVES

To compare the performance of self-collected vaginal (V) specimens with clinician-collected cervical (C) specimens for detection of high-risk human papillomavirus (hrHPV) and cervical disease using the Cepheid Xpert HPV, Roche Cobas 4800 HPV and Hologic Aptima HPV assays.

METHODS

Women aged 30-59 years (n = 1005) were recruited at two clinics in Papua New Guinea, and they provided specimens for testing at point-of-care using the Xpert HPV Test, and for subsequent testing using the Cobas HPV (n = 981) and Aptima HPV (n = 983) assays. Liquid-based cytology was performed on C specimens to predict underlying high-grade squamous intraepithelial lesions (HSIL). V specimen results of each assay were evaluated against a constructed reference standard and for detection of HSIL or worse.

RESULTS

There was substantial (κ >0.6) agreement in hrHPV detection between V and C specimens across all three assays. The sensitivity, specificity, and positive and negative predictive values of Xpert HPV using self-collected V specimens for the detection of HPV type 16 according to the constructed reference standard were 92.1%, 93.1%, 63.6% and 98.9%, respectively; compared with 90.4%, 94.3%, 67.8% and 98.7% for Cobas 4800 HPV; and 63.2%, 97.2%, 75.0% and 95.3% for Aptima HPV. Similar results were observed for all hrHPV types (combined) and for HPV types 18/45, on all three assays. The detection of any hrHPV using self-collected specimens had high sensitivity (86%-92%), specificity (87%-94%) and negative predictive value (>98%) on all assays for HSIL positivity.

CONCLUSIONS

Xpert HPV, using self-collected vaginal specimens, has sufficient accuracy for use in point-of-care 'test-and-treat' cervical screening strategies in high-burden, low-resource settings.

Innovative approaches to cervical cancer screening in low- and middle-income countries

The estimated cervical cancer burden is over ten-fold greater in low- and middle-income countries (LMICs) than in high-income countries. This health gap is thought to be primarily due to limited access to effective screening and treatment programs for cervical pre-cancer and cancer in such settings. The World Health Organization advocates a policy of 'screen and treat' approach to cervical screening in LMICs and subsequently visual inspection of the cervix with acetic acid (VIA) or Lugo's iodine (VILI), followed by ablative cervical cryotherapy if indicated, and this policy has been implemented in many high-burden settings. The performance of VIA/VILI as a primary screening tool for the detection of cervical pre-cancer and cancer has, however, been inconsistent. Recently, many high-income countries have integrated HPV-DNA testing into their cervical cancer screening programs. The comparatively high cost and resource requirements of HPV-based screening have to date prevented many LMICs from doing the same. A significant development has been the entrance of innovative, easy-to-use and highly accurate HPV tests that can be provided at point of care; these could enable LMICs to implement 'test and treat' approaches for cervical cancer screening.