Self-sampling as the principal modality for population based cervical screening: Five-year follow-up of the PaVDaG study

Variables that impact HPV test accuracy during vaginal self collection workflow for cervical cancer screening

Vaginal self collection (SC) is safe and effective for human papillomavirus (HPV) testing and can increase cervical cancer screening coverage for underserved women. To better understand the impact of SC methodology on HPV test outcomes, empirical testing was conducted using different swab collection workflows. Deposition of the collection swab into resuspension buffer resulted in a 2.4-cycle reduction in threshold detection of human beta-hemoglobin during PCR when compared to "swirl-and-toss". In addition, reducing the swab resuspension volume from 10 mL to 3 mL resulted in a 2.6-cycle reduction in threshold detection of human beta-globin. A systematic literature search (01/01/2020 to 08/02/2023) of Ovid Medline and Embase, followed by data extraction and analysis, was conducted to further assess the impact of resuspension volume on performance following SC. HPV test performance for SC, relative to clinician collection (CC), was calculated for detection of cervical pre-cancer. Data were stratified by the resuspension volume ratio of SC to CC being either ≥ 1.0 or < 1.0. SC with a volume ratio of ≥ 1.0 and < 1.0 had a relative ≥ CIN2 sensitivity of 92.0 % (95 % CI: 88.0, 96.0) and 97.0 % (95 % CI: 94.0, 100), respectively. Taken together, these results suggest that SC conditions can be modified to optimize sample recovery and performance, as part of cervical cancer screening.

Self-sampling for HPV testing in cervical cancer screening: A scoping review

Cervical cancer is the third most common gynecological cancer worldwide. Its origin is linked to intraepithelial lesions caused by high-risk Human Papillomavirus (HPV) types, detected in 99.7% of cases. Early screening is essential to prevent cancer development from these lesions. Molecular methods are more specific and offer the possibility of being performed through a self-collected sample by the patient, thus contributing to increasing screening coverage for this pathology. This study aim was to map the medical-scientific literature on existing protocols for self-sampling for HPV testing in cervical cancer screening. A search strategy was developed using the following keywords and their synonyms: "self-sampling," "professional sampling," and "HPV", on the databases: MEDLINE, Cochrane Library, Virtual Health Library - BVS, Scopus, National Institute for Health Research NHS EED, Web of Science, and EMBASE. The search strategy was formulated to identify relevant studies and describe their main characteristics, such as patient acceptance of self-sampling, cost differences between the tests used, and the accuracy of self-sampling compared to the gold standard test. A total of 876 studies were found, and 33 of those studies were included in this review. Out of these, 10 studies were domized clinical trials involving 46,751 patients, and 23 observational studies included 142,795 patients. Regarding acceptance, most studies reported a preference for self-sampling. Sensitivity analyses from various studies also showed that the low cost of self-sampling kits generally increased cost-effectiveness. The study concluded that using HPV testing on self-collected samples is a viable strategy for monitoring women with HPV.

Older women's perceptions of HPV self-sampling and HPV-sampling performed by a midwife - a phenomenographic study

BACKGROUND

Cervical cancer is a global disease and it is well established that cervical cancer is caused by human papillomavirus (HPV). In Sweden self-sampling for HPV is now used as a complement to sampling performed by a midwife. However, there is a lack of knowledge on how older women perceive the self-sampling compared to the sampling performed by a midwife. Therefore, the aim of the study was to describe how women, aged 64 years and older, perceived the process of self-sampling and sampling performed by a midwife for HPV-testing.

METHODS

Eighteen women were included in a qualitative interview study, and a phenomenographic approach was used for the analysis of the interviews.

RESULTS

Three descriptive categories emerged: Confidence in sampling, Facilitating participation and Being informed. Within the categories, eight conceptions emerged describing the variation relating to how the women perceived the process of self-sampling and sampling performed by a midwife.

CONCLUSIONS

Women in this study describe confidence in self-sampling for HPV-testing and that the self-sampling was saving time and money, both for themselves and for society. Information in relation to an HPV-positive test result is of importance and it must be kept in mind that women affected by HPV may feel guilt and shame, which health care professionals should pay attention to. This knowledge can be used in education of health care staff.

TRIAL REGISTRATION

https://researchweb.org/is/fourol/project/228071 . Reg. no 228,071.

Widening the offer of human papillomavirus self-sampling to all women eligible for cervical screening: Make haste slowly

Self-collection of samples for human papillomavirus (HPV) testing has the potential to increase the uptake of cervical screening among underscreened women and will likely form a crucial part of the WHO's strategy to eliminate cervical cancer by 2030. In high-income countries with long-standing, organised cervical screening programmes, self-collection is increasingly becoming available as a routine offer for women regardless of their screening histories, including under- and well-screened women. For these contexts, a validated microsimulation model determined that adding self-collection to clinician collection is likely to be cost-effective on the condition that it meets specific thresholds relating to (1) uptake and (2) sensitivity for the detection of high-grade cervical intraepithelial neoplasia (CIN2+). We used these thresholds to review the 'early-adopter' programme-level evidence with a mind to determine how well and how consistently they were being met. The available evidence suggested some risk to overall programme performance in the situation where low uptake among underscreened women was accompanied by a high rate of substituting clinician sampling with self-collection among well-screened women. Risk was further compounded in a situation where the slightly reduced sensitivity of self-sampling vs clinician sampling for the detection of CIN2+ was accompanied with lack of adherence to a follow-up triage test that required a clinician sample. To support real-world programmes on their pathways toward implementation and to avoid HPV self-collection being introduced as a screening measure in good faith but with counterproductive consequences, we conclude by identifying a range of mitigations and areas worthy of research prioritisation.

Human papillomavirus testing on self-collected samples to detect high-grade cervical lesions in rural Bhutan: The REACH-Bhutan study

BACKGROUND

"REACH-Bhutan" aimed to evaluate the feasibility and clinical performance of a community-based screening program for cervical cancer in rural Bhutan using self-collected samples for high-risk human papillomavirus (HR-HPV) testing.

METHODS

In April/May 2016, 2590 women aged 30-60 years were screened across rural Bhutan by providing a self-collected sample for careHPV testing. All careHPV-positive women, plus a random sample of careHPV-negative women, were recalled for colposcopy and biopsy. Self-samples also underwent GP5+/6+ polymerase chain reaction (PCR)-based HR-HPV DNA detection and genotyping. Cross-sectional screening indices were estimated against histological high-grade squamous intraepithelial lesions or worse (hHSIL+), including imputation of hHSIL+ in women without colposcopy.

RESULTS

HR-HPV positivity was 10.2% by careHPV and 14.8% by GP5+/6+ PCR. Twenty-two cases of hHSIL+ were histologically diagnosed, including one invasive cancer; an additional 7 hHSIL+ were imputed in women without colposcopy. HR-HPV testing by GP5+/6+ showed higher sensitivity for hHSIL+ (89.7%, 95% CI 72.6-97.8) than careHPV (75.9%, 95% CI 56.5-89.7). Negative predictive value was also slightly higher for GP5+/6+ (99.9%, 95% CI 99.6-100) than careHPV (99.7%, 95% CI 99.4-99.9). Specificity, however, was lower for GP5+/6+ (86.1%, 95% CI 84.6-87.4) than careHPV (90.6%, 95% CI 89.4-91.7), as was positive predictive value (6.9%, 95% CI 4.5-9.9 vs. 8.5%, 95% CI 5.4-12.6). Of 377 HR-HPV-positive women by GP5+/6+, 173 (45.9%) were careHPV-positive, including 54.7% HPV16-positive and 30.2% HPV18-positive women.

CONCLUSIONS

The final REACH-Bhutan results show that screening for cervical cancer with self-collection of samples and HR-HPV testing, in addition to our previous report of achieving high participation, can also perform well to detect women with hHSIL+.

Non-speculum clinician-taken samples for human papillomavirus testing: a cross-sectional study in older women

BACKGROUND

Cervical cancer incidence and mortality are high in women aged ≥65 years, despite the disease being preventable by screening. Speculum-based screening can become more uncomfortable after the menopause.

AIM

To examine test performance and acceptability of human papillomavirus (HPV) testing on clinician-collected vaginal samples without a speculum (non-speculum).

DESIGN AND SETTING

Cross-sectional study in 11 GP practices and four colposcopy clinics in London, UK, between August 2017 and January 2019.

METHOD

Non-speculum and conventional (speculum) samples were collected from women aged ≥50 years attending for a colposcopy (following a speculum HPV-positive screening result) or women aged ≥35 years (with confirmed cervical intraepithelial neoplasia (CIN) 2+), and women aged 50-64 years attending routine screening. Sensitivity to CIN2+ was assessed among women with confirmed CIN2+ (colposcopy). Specificity to HPV relative to speculum sampling and overall concordance was assessed among women with negative cytology (routine screening).

RESULTS

The sensitivity of non-speculum sampling for detecting CIN2+ was 83.3% (95% confidence interval [CI] = 60.8 to 94.2) (n = 15/18). There was complete concordance among women with positive CIN2+ who had a speculum sample ≤91 days prior to the non-speculum sample (n = 12). Among 204 women with negative cytology, the specificity to HPV was 96.4% (95% CI = 92.7 to 98.5), with 96.6% concordant results (κ 72.4%). Seventy-one percent (n = 120/170) of women preferred a non-speculum sample for their next screen.

CONCLUSION

HPV testing on non-speculum clinician-taken samples is a viable approach that warrants further exploration in larger studies. Overall test performance was broadly comparable with that of self-sampling.

Clinical Performance of Triage Strategies for Hr-HPV-Positive Women; A Longitudinal Evaluation of Cytology, p16/K-67 Dual Stain Cytology, and HPV16/18 Genotyping

BACKGROUND

We evaluated the longitudinal performance of three options: HPV16/18 genotyping (HPV16/18), cytology (LBC), and p16/Ki-67 dual stain cytology (DS) for the triage of high-risk Human Papillomavirus-positive (Hr-HPV+) women within the cervical screening program in Scotland.

METHODS

Data were derived from a cohort of Hr-HPV+ women (n = 385) who participated in PaVDaG (Papillomavirus Dumfries and Galloway) study. Performance of triage strategies for detecting high-grade disease was assessed at 3 (in women <50 years) or 5 years (in women >50 years). Sensitivity, specificity, PPV, and cNPV of each triage test were calculated for CIN2+ and CIN3+ when used singly or sequentially.

RESULTS

The sensitivity of LBC (≥ borderline), DS, and HPV 16/18 genotyping for the detection of CIN2+ was 62.7% (50.7-73.3), 77.7% (63.1-83.7), and 62.7% (50.7-73.3) with corresponding cNPVs of 10.9%, 8.4%, and 11.9%. The option with the highest sensitivity and lowest cNPV was HPV 16/18 genotyping followed by LBC of Hr-HPV other+ and then DS of the LBC negatives. This yielded sensitivity of 94.7% (86.2-98.3) and cNPV 2.7% for CIN2+. Triage performance was similar if women had tested Hr-HPV+ positive by vaginal self-sampling.

CONCLUSIONS

Two-step triage with HPV 16/18 genotyping before LBC (or DS) for Hr-HPV other+ women was associated with a lower risk of significant disease at follow-up compared with single triage approaches.

IMPACT

This study provides longitudinal performance data on triage strategies in Hr-HPV+ women and will be informative for the evolution of cervical screening programs that increasingly rely on molecular technologies.

Improving the uptake of cervical screening in pregnant and recently postnatal women: a quality improvement project

BACKGROUND

In 2018, cervical screening uptake was at its lowest level since screening began, particularly in those aged 25-35, coinciding with the peak incidence of cervical cancer and average age at first delivery.

PROBLEM

Retrospective baseline data of pregnant women found 47.3% (n=123/260) were overdue for screening by delivery, of whom 74% (n=91/123) remained overdue by 6 months postnatal.

METHODS

We undertook a quality improvement project from April 2018 to April 2019 to improve cervical screening uptake in pregnant and postnatal women. We mapped out the screening process and canvassed stakeholders. The main theme was inconsistency of advice received by women. From February 2018 to May 2020, we undertook a prospective audit of 10 women per week who gave birth in our maternity department, recording screening status at delivery and 6 months postnatal.Interventions included introducing evidence-based guidelines about cervical screening in pregnancy and the postnatal period, flow charts for maternity staff, multiprofessional teaching for all maternity staff and information dissemination to women (via the HANDiApp platform, a social media campaign and adapting results letters following colposcopy, highlighting dates when screening would be due). Primary care opening hours were extended for screening and women received a letter from their midwives, if they required cervical screening in pregnancy.

RESULTS

Locally, the percentage of women overdue for cervical screening by 6 months postnatal improved by 8.0% during this project, compared with a 1.6% change in national screening rates in women aged 25-49.

CONCLUSIONS

We increased the percentage of local pregnant and postnatal women attending cervical screening by introduction of a package of information, targeted education and widening access to screening appointments.