Optimising future cervical screening strategies

Screening for the prevention and early detection of cervical cancer: protocol for systematic reviews to inform Canadian recommendations

PURPOSE

To inform recommendations by the Canadian Task Force on Preventive Health Care on screening in primary care for the prevention and early detection of cervical cancer by systematically reviewing evidence of (a) effectiveness; (b) test accuracy; (c) individuals' values and preferences; and (d) strategies aimed at improving screening rates.

METHODS

De novo reviews will be conducted to evaluate effectiveness and to assess values and preferences. For test accuracy and strategies to improve screening rates, we will integrate studies from existing systematic reviews with search updates to the present. Two Cochrane reviews will provide evidence of adverse pregnancy outcomes from the conservative management of cervical intraepithelial neoplasia. We will search Medline, Embase, and Cochrane Central (except for individuals' values and preferences, where Medline, Scopus, and EconLit will be searched) via peer-reviewed search strategies and the reference lists of included studies and reviews. We will search ClinicalTrials.gov and the World Health Organization International Clinical Trials Registry Platform for ongoing trials. Two reviewers will screen potentially eligible studies and agree on those to include. Data will be extracted by one reviewer with verification by another. Two reviewers will independently assess risk of bias and reach consensus. Where possible and suitable, we will pool studies via meta-analysis. We will compare accuracy data per outcome and per comparison using the Rutter and Gatsonis hierarchical summary receiver operating characteristic model and report relative sensitivities and specificities. Findings on values and preferences will be synthesized using a narrative synthesis approach and thematic analysis, depending on study designs. Two reviewers will appraise the certainty of evidence for all outcomes using GRADE (Grading of Recommendations Assessment, Development and Evaluation) and come to consensus.

DISCUSSION

The publication of guidance on screening in primary care for the prevention and early detection of cervical cancer by the Task Force in 2013 focused on cytology. Since 2013, new studies using human papillomavirus tests for cervical screening have been published that will improve our understanding of screening in primary care settings. This review will inform updated recommendations based on currently available studies and address key evidence gaps noted in our previous review.

Acceptability of self- collection for human papillomavirus detection in the Eastern Cape, South Africa

Human papillomavirus (HPV) testing on vaginal self-collected and cervical clinician-collected specimens shows comparable performance. Self-sampling on FTA cards is suitable for women residing in rural settings or not attending regular screening and increases participation rate in the cervical cancer screening programme. We aimed to investigate and compare high-risk (HR)-HPV prevalence in clinician-collected and self-collected genital specimens as well as two different HPV tests on the clinician collected samples. A total of 737 women were recruited from two sites, a community health clinic (n = 413) and a referral clinic (n = 324) in the Eastern Cape Province. Cervical clinician-collected (FTA cards and Digene transport medium) and vaginal self-collected specimens were tested for HR-HPV using the hpVIR assay (FTA cards) and Hybrid Capture-2 (Digene transport medium). There was no significant difference in HR-HPV positivity between clinician-collected and self-collected specimens among women from the community-based clinic (26.4% vs 27.9%, p = 0.601) or the referral clinic (83.6% vs 79.9%, p = 0.222). HPV16, HPV35, and HPV33/52/58 group were the most frequently detected genotypes at both study sites. Self-sampling for HPV testing received a high positive response of acceptance (77.2% in the community-based clinic and 83.0% in referral clinic). The overall agreement between hpVIR assay and HC-2 was 87.7% (k = 0.754). The study found good agreement between clinician-collected and self-collected genital specimens. Self-collection can have a positive impact on a cervical screening program in South Africa by increasing coverage of women in rural areas, in particular those unable to visit the clinics and women attending clinics where cytology-based programs are not functioning effectively.