Reliability of the Xpert HPV assay to detect high-risk human papillomavirus DNA in a colposcopy referral population

Expanding management strategies for cervical precancerous lesions in resource-limited settings: insights from a training center in a district hospital in Ghana

BACKGROUND

Cervical cancer continues to disproportionately burden women in low/middle-income countries like Ghana. We examined treatment patterns and histopathological outcomes among women screened using visual inspection with acetic acid (VIA) and/or mobile colposcopy who subsequently underwent thermal ablation, large loop excision of the transformation zone (LLETZ), or cold knife conization at the Cervical Cancer Prevention and Training Centre, Battor. We also assessed the prevalence of cervical intraepithelial neoplasia 2+ (CIN2+) or micro-invasive disease and their associated factors for women who underwent excisional treatments. The treatment choices for cervical precancerous lesions suitable for resource-limited settings have also been described from the perspective of a center that manages a heterogenous population.

METHODS

We conducted an analysis of secondary data collected between June 2016 and June 2023 among women with positive findings on VIA or mobile colposcopy who subsequently underwent thermal ablation or large loop excision of the transformation zone (LLETZ). The prevalence of histopathology outcomes, including no dysplasia, CIN1 - 3, and micro-invasive disease, were estimated with 95% confidence intervals (CIs). Factors associated with histopathological findings were modeled using multinomial logistic regression.

RESULTS

For the study period, 14 (10.6%) of the total 132 participants underwent cervical lesion treatment at outreach locations, all via thermal ablation. The remaining 118 (89.4%) were treated at the Catholic Hospital, Battor using LLETZ (n = 66, 55.9%), thermal ablation (n = 51, 43.2%), and cold knife conization (n = 1, 0.9%). Among 65 women with histopathology reports, the most frequent histopathological finding was no dysplasia (47.7%; 95% CI, 35.1 - 60.5), followed by CIN2 and CIN3 (20.0%; 95% CI, 11.1 - 31.8 each), CIN1 (7.7%; 95% CI, 2.5 - 17.0) and micro-invasion (4.6%; 95% CI, 1.0 - 12.9). Those with micro-invasive disease were significantly older than those with CIN1, CIN2, and CIN3 (p = 0.036, 0.022, 0.009, respectively), but not significantly older than those who showed no dysplasia (p = 0.088). For each unit increase in age, the likelihood of CIN3 was relatively significantly reduced compared to no dysplasia (crude relative risk ratio [RRR] = 0.93; 95% CI, 0.86 - 0.99). This association was neither observed with the remaining histopathological groups nor for parity and persisted after controlling for parity (adjusted RRR = 0.92; 95% CI, 0.85 - 0.99; p = 0.025).

CONCLUSION

This paper largely demonstrates treatment options available to women and practitioners in LMICs. The high combined prevalence of high-grade precancerous lesions and micro-invasive disease underscores the need to increase cervical cancer awareness that would enhance screening attendance and hasten efforts at moving from opportunistic to organized screening in Ghana. This will enhance early cervical lesion detection and treatment, while simultaneously re-evaluating and cutting down on unnecessary treatment.

Empowering the on-site detection of nucleic acids by integrating CRISPR and digital signal processing

Addressing the global disparity in cancer care necessitates the development of rapid and affordable nucleic acid (NA) testing technologies. This need is particularly critical for cervical cancer, where molecular detection of human papillomavirus (HPV) has emerged as an accurate screening method. However, implementing this transition in low- and middle-income countries has been challenging due to the high costs and centralized facilities required for current NA tests. Here, we present CreDiT (CRISPR Enhanced Digital Testing) for on-site NA detection. The CreDiT platform integrates i) a one-pot CRISPR strategy that simultaneously amplifies both target NAs and analytical signals and ii) a robust fluorescent detection based on digital communication (encoding/decoding) technology. These features enable a rapid assay (<35 minutes) in a single streamlined workflow. We demonstrate the sensitive detection of cell-derived HPV DNA targets down to single copies and accurate identification of HPV types in clinical cervical brushing specimens (n = 121).

Comparison of the ScreenFire and Xpert HPV assays for the detection of human papillomavirus and cervical precancer among women living with HIV in Malawi

BACKGROUND

The World Health Organization recommends human papillomavirus (HPV) testing for primary cervical cancer screening, including among women living with HIV (WLWH). Low-and-middle-income countries account for 85% of the cervical cancer burden globally, yet have limited access to HPV-based screening, largely due to cost. This study aims to compare the performance of a rapid, isothermal amplification HPV assay (ScreenFire) to that of the Xpert HPV assay for the detection of HPV and cervical precancer among WLWH in Malawi.

METHODS

We utilized stored self- and provider-collected specimens from a prospective cohort study of WLWH in Malawi from July 2020 to February 2022. Specimens were tested with both Xpert and ScreenFire HPV assays. The overall and within-channel non-hierarchical agreement between ScreenFire and Xpert was determined for both self- and provider-collected specimens. Hierarchical ScreenFire HPV positivity by channel was compared to Xpert for each histological diagnosis-cervical intraepithelial neoplasia grade 2 or worse (CIN2+) compared to

RESULTS

315 matched self- and provider-collected specimens had valid results from both Xpert and ScreenFire testing and were included in analyses, of which 279 and 36 were HPV positive and HPV negative, respectively, on Xpert self-collection. Of the 315, 245 (78%) had normal pathology, 21 CIN1 (7%), 14 CIN2 (4%), and 35 CIN3 (11%). Of the 245 with normal pathology, 213 (87%) and 188 (77%) were HPV-positive on Xpert and ScreenFire self-collected specimens, respectively. Among provider-collected specimens, the assays had 80% agreement on overall HPV positivity (unweighted kappa 0.59, 95% 0.50-0.69). ScreenFire was HPV-positive in 90% of self-collected specimens that were HPV-positive on Xpert. Channel agreement between the assays was high for both self- and provider-collected specimens, but slightly lower for HPV18/45. In hierarchical analysis, ScreenFire demonstrated high concordance with Xpert testing for detecting CIN2+ cases in all channels, missing no HPV 16 or HPV 18/45 positive CIN2+ case that was positive on Xpert, in both self- and provider-collected specimens.

CONCLUSION

In this study of stored specimens, the ScreenFire HPV assay performed well in the detection of HPV and CIN2+ among WLWH compared to the Xpert HPV assay. If supported by larger validation studies, ScreenFire could be an affordable alternative point-of-care HPV assay for use in LMICs.

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Grants

• K12 HD103085 NICHD NIH HHS
• U54 CA254564 NCI NIH HHS
• K12HD103085 Eunice Kennedy Shriver National Institute of Child Health & Human Development of the National Institutes of Health
• Eunice Kennedy Shriver National Institute of Child Health & Human Development of the National Institutes of Health

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Affiliation(s)

Chemtai Mungo Department of Obstetrics and Gynecology, University of North Carolina-Chapel Hill, Chapel Hill, NC, USA.
Anagha Guliam Barnard College of Columbia University, New York City, NY, USA
Lameck Chinula Department of Obstetrics and Gynecology, University of North Carolina-Chapel Hill, Chapel Hill, NC, USA University of North Carolina Project-Malawi, Lilongwe, Malawi
Federica Inturrisi Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Rockville, MD, USA
Lizzie Msowoya University of North Carolina Project-Malawi, Lilongwe, Malawi
Tawonga Mkochi University of North Carolina Project-Malawi, Lilongwe, Malawi
Siniya Jawadu University of North Carolina Project-Malawi, Lilongwe, Malawi
Silvia de Sanjosé Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Rockville, MD, USA ISGlobal, Barcelona, Spain
Mark Schiffman Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Rockville, MD, USA
Jennifer H Tang Department of Obstetrics and Gynecology, University of North Carolina-Chapel Hill, Chapel Hill, NC, USA University of North Carolina Project-Malawi, Lilongwe, Malawi
Jennifer S Smith Gillings School of Global Public Health, University of North Carolina-Chapel Hill, Chapel Hill, NC, USA

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Comparison of the ScreenFire and Xpert HPV assays for the detection of human papillomavirus and cervical precancer among women living with HIV in Malawi

Background

The World Health Organization (WHO) recommends human papillomavirus (HPV) testing for primary cervical cancer screening, including among women living with HIV (WLWH). Low-and-middle-income countries (LMICs) account for 85% of the cervical cancer burden globally, yet have limited access to HPV-based screening, largely due to cost. This study aims to compare the performance of a rapid, isothermal amplification HPV assay (ScreenFire) to that of the Xpert HPV assay for the detection of HPV and cervical precancer among WLWH in Malawi.

Methods

We utilized stored self- and provider-collected specimens from a prospective cohort study of WLWH in Malawi from July 2020 to February 2022. Specimens were tested with both Xpert and ScreenFire HPV assays. The overall and within-channel non-hierarchical agreement between ScreenFire and Xpert was determined for both self- and provider-collected specimens. Hierarchical ScreenFire HPV positivity by channel was compared to Xpert for each histological diagnosis - cervical intraepithelial neoplasia grade 2 or worse (CIN2+) compared to

Results

315 matched self- and provider-collected specimens had valid results from both Xpert and ScreenFire testing and were included in analyses. Of these, 245 (78%) had normal pathology, 21 CIN1 (7%), 14 CIN2 (4%), and 35 CIN3 (11%). Among provider-collected specimens, the assays had 80% agreement on overall HPV positivity (unweighted kappa 0.59, 95% 0.50-0.69). ScreenFire was HPV-positive in 90% of self-collected specimens that were HPV-positive on Xpert. Channel agreement between the assays was high for both self- and provider-collected specimens, but slightly lower for HPV18/45. In hierarchical analysis, ScreenFire demonstrated high concordance with Xpert testing for detecting CIN2+ cases in all channels, missing no HPV 16 or HPV 18/45 positive CIN2+ case that was positive on Xpert, in both self- and provider-collected specimens.

Conclusion

In this study of stored specimens, the ScreenFire HPV assay performed well in the detection of HPV and CIN2+ among WLWH compared to the Xpert HPV assay. If supported by larger validation studies, ScreenFire could be an affordable alternative point-of-care HPV assay for use in LMICs.

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Key Words Collapse

MESH Headings Collapse

Grants

• K12 HD103085 NICHD NIH HHS

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Affiliation(s)

Chemtai Mungo Department of Obstetrics and Gynecology, University of North Carolina-Chapel Hill
Anagha Guliam Barnard College of Columbia University
Lameck Chinula Department of Obstetrics and Gynecology, University of North Carolina-Chapel Hill University of North Carolina Project-Malawi, Lilongwe, Malawi
Federica Inturrisi Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Rockville, MD, USA
Lizzie Msowoya University of North Carolina Project-Malawi, Lilongwe, Malawi
Tawonga Mkochi University of North Carolina Project-Malawi, Lilongwe, Malawi
Siniya Jawadu University of North Carolina Project-Malawi, Lilongwe, Malawi
Silvia de Sanjosé Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Rockville, MD, USA Gillings School of Global Public Health, University of North Carolina-Chapel Hill
Mark Schiffman Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Rockville, MD, USA
Jennifer H. Tang Department of Obstetrics and Gynecology, University of North Carolina-Chapel Hill University of North Carolina Project-Malawi, Lilongwe, Malawi
Jennifer S. Smith Gillings School of Global Public Health, University of North Carolina-Chapel Hill

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Tritesting in Battor, Ghana: an integrated cervical precancer screening strategy to mitigate the challenges of multiple screening visits and loss to follow-up

Background

Human papillomavirus (HPV) DNA testing is more sensitive than cytology for detecting cervical precancer; however, increasing reports of high-risk HPV (hr-HPV)-negative cases of cervical intraepithelial neoplasia (CIN) and even malignancy motivate the use of combined testing. We present our experience with 'tritesting', defined as the performance of HPV DNA testing, cytology and visual inspection in a single session at the Cervical Cancer Prevention and Training Centre, Ghana. We further determined the prevalence rates of hr-HPV infection, abnormal cytology and cervical lesions among women screened using tritesting.

Methods

This descriptive retrospective cross-sectional study assessed all women screened via tritesting between April 2019 to April 2023. HPV DNA testing was performed using the Sansure MA-6000, GeneXpert or AmpFire platforms. Visual inspection was performed using enhanced visual assessment mobile colposcopy or visual inspection with acetic acid. Liquid-based cytology was performed using cervical samples taken with a Cervex-Brush® and fixed in PreservCyt, while samples for conventional cytology were taken using an Ayre spatula and cytobrush.

Results

Among 236 women screened (mean age, 39.1 years (standard deviation, 10.9)), the overall prevalence rates of hr-HPV infection and cervical lesions were 17.8% (95% confidence interval (CI), 13.1-23.3) and 11.9% (95% CI, 8.0-16.7), respectively. Cytology yielded findings of atypical squamous cells of undetermined significance or worse in 2.5% (95% CI, 0.9-5.5) of women. Histopathology following loop electrosurgical excision procedure revealed CIN I (tritest positive) and CIN III (hr-HPV-positive, visual inspection 'positive', cytology-negative) in one woman each. Factors independently associated with hr-HPV infection among 'tritested' women were age ≥ 39 years, tertiary level of education and current contraceptive use. Twenty-seven out of 39 hr-HPV-positive women (69.2%; 95% CI, 52.4-83.0) showed a type 3 transformation zone and would have needed to be recalled for a cytologic sample to be taken in a 'see and triage' approach with HPV DNA testing and a visual inspection method.

Conclusion

This study brings tritesting into the spotlight, as an alternative to other methods, particularly for women who prefer this due to the advantage of a single visit to a health facility and being more cost-effective, if they have to travel long distances to access cervical screening services.

Increased expression of HPV-E7 oncoprotein correlates with a reduced level of pRb proteins via high viral load in cervical cancer

Human Papillomavirus (HPV) is the most common cause of sexually transmitted diseases and causes a wide range of pathologies including cervical carcinoma. Integration of the HR-HPV DNA into the host genome plays a crucial role in cervical carcinoma. An alteration of the pRb pathways by the E7 proteins is one of the mechanisms that's account for the transforming capacity of high-risk papillomavirus. For the proper understanding of the underline mechanism of the progression of the disease, the present study investigate the correlation of concentration of host pRb protein, viral E7 oncoprotein and viral load in early and advanced stages of cervical carcinoma. It was found that the viral load in early stages (stage I and II) was less (log10 transformed mean value 2.6 and 3.0) compared to advanced stages (stage III and IV) (Log10 transformed value 5.0 and 5.8) having high expression of HPV E7 onco-protein and reduced level of pRb protein, signifying the role of viral load and expression level of E7 oncoprotein in the progression of cervical cancer.

Comparison of the Clinical Accuracy of Xpert HPV Assay on Vaginal Self-Samples and Cervical Clinician-Taken Samples within the VALHUDES Framework

The accuracy of high-risk human papillomavirus testing with the Xpert HPV assay on vaginal self-samples was compared with clinician-taken samples within the VALidation of HUman papillomavirus assays and collection DEvices for Self-samples and urine samples (VALHUDES) framework. Five-hundred and twenty-three women were recruited in five Belgian colposcopy clinics, of whom 483 (median age, 40 years; interquartile range, 31 to 49 years) were included in the main analysis (226 collected with Evalyn Brush and 257 collected with Qvintip). Cervical samples were collected with Cervex-Brush. Colposcopy and histology outcomes were considered as the reference standard. The Xpert HPV assay had similar accuracy for cervical intraepithelial neoplasia ≥2 on self-collected versus clinician-collected samples [relative sensitivity, 0.96 (95% CI, 0.91-1.02); and relative specificity, 0.96 (95% CI, 0.89-1.04)]. The relative accuracy slightly differed by vaginal collection device [sensitivity ratios of 0.98 (95% CI, 0.90-1.06) and 0.94 (95% CI, 0.87-1.02) for Evalyn and Qvintip, respectively; specificity ratios of 1.06 (95% CI, 0.95-1.19) and 0.88 (95% CI, 0.80-0.98) for Evalyn and Qvintip, respectively]. No difference in cycle threshold values was observed between vaginal and cervical samples. In conclusion, the sensitivity of Xpert HPV assay for cervical intraepithelial neoplasia ≥2 on vaginal self-samples was similar to that of cervical specimens. The clinical specificity was lower than on clinician-collected samples when self-samples were taken with Qvintip.

An integrated isothermal nucleic acid amplification test to detect HPV16 and HPV18 DNA in resource-limited settings

High-risk human papillomavirus (HPV) DNA testing is widely acknowledged as the most sensitive cervical cancer screening method but has limited availability in resource-limited settings, where the burden of cervical cancer is highest. Recently, HPV DNA tests have been developed for use in resource-limited settings, but they remain too costly for widespread use and require instruments that are often limited to centralized laboratories. To help meet the global need for low-cost cervical cancer screening, we developed a prototype, sample-to-answer, point-of-care test for HPV16 and HPV18 DNA. Our test relies on isothermal DNA amplification and lateral flow detection, two technologies that reduce the need for complex instrumentation. We integrated all test components into a low-cost, manufacturable platform, and performance of the integrated test was evaluated with synthetic samples, provider-collected clinical samples in a high-resource setting in the United States, and self-collected clinical samples in a low-resource setting in Mozambique. We demonstrated a clinically relevant limit of detection of 1000 HPV16 or HPV18 DNA copies per test. The test requires six user steps, yields results in 45 min, and can be performed using a benchtop instrument and minicentrifuge by minimally trained personnel. The projected per-test cost is <$5, and the projected instrumentation cost is <$1000. These results show the feasibility of a sample-to-answer, point-of-care HPV DNA test. With the inclusion of other HPV types, this test has the potential to fill a critical gap for decentralized and globally accessible cervical cancer screening.

Oncoviruses and melanomas: A retrospective study and literature review

The role of human oncoviruses in melanoma has been poorly investigated. The aim of this study was to investigate the association between oncoviruses and melanomas searching for human papillomavirus (HPV), Epstein Barr virus (EBV), and human herpesvirus 8DNA in melanoma specimens. Formalin-fixed and paraffin-embedded tissue specimens of cutaneous, mucosal, and ocular melanomas (OM) were selected from the Pathology Departments of the Galliera Hospital (Genoa) and the University Hospitals of Turin and Cagliari. Cutaneous and mucosal nevi have been collected as controls. The oncoviruses search has been performed with different polymerase chain reaction reagent kits. Fifty-four melanomas (25 mucosal, 12 ocular, and 17 cutaneous) and 26 nevi (15 cutaneous and 11 mucosal) specimens were selected. The detection rate for one of the investigated oncoviruses was 17% in mucosal, 20% in ocular, and 0% in cutaneous melanomas (CMs). Despite the differences between groups seeming remarkable, there was no statistical significance (p > 0.5). Our data do not support a primary role of oncoviruses in melanoma carcinogenesis; however, the finding of HPV and EBV DNA in a considerable fraction of mucosal and OMs suggests that these viruses may act as cofactors in the development of extra-CMs.

Agreement between Xpert and AmpFire tests for high-risk human papillomavirus among HIV-positive women in Rwanda

BACKGROUND

High-risk human papillomavirus (hrHPV) may cause more than 99% of cervical cancers worldwide. Little is known about performance differences in tests for hrHPV.

OBJECTIVE

This study analysed agreement for detection of hrHPV between the established, clinically validated Xpert HPV assay and the novel isothermal amplification-based AmpFire HPV genotyping assay.

METHODS

This study was nested in a larger project on cervical cancer screening among approximately 5000 women living with HIV in Kigali, Rwanda. This sub-study included 298 participants who underwent initial screening for cervical cancer using the Xpert HPV assay and visual inspection with acetic acid in 2017 and tested positive by either or both. Participants were rescreened using colposcopy, and cervical samples were collected between June 2018 and June 2019. Samples were then tested for HPV using the Xpert HPV assay and AmpFire HPV genotyping assay. Agreement between results from both tests was analysed using an exact version of McNemar test and chi-square test.

RESULTS

Overall agreement and kappa value for detection of hrHPV by Xpert and AmpFire were 89% and 0.77 (95% confidence interval: 0.70-0.85). AmpFire was marginally more likely to diagnose hrHPV-positive than Xpert (p = 0.05), due primarily to the extra positivity for HPV16 (p < 0.001).

CONCLUSION

Overall, there was good to excellent agreement between the Xpert and AmpFire when testing hrHPV types among women living with HIV. AmpFire was more likely to test extra cases of HPV16, the most carcinogenic HPV type, but the clinical meaning of detecting additional HPV16 infections remains unknown.

A Randomized Clinical Trial of Human Papillomavirus Test-and-Treat as Compared to Cytology-Based Screening for Prevention of Cervical Cancer Among Women With Human Immunodeficiency Virus: AIDS Clinical Trials Group Protocol A5282

BACKGROUND

Cytology-based cervical cancer screening followed by confirmation and treatment of biopsy-proven high-grade squamous intraepithelial lesions (bHSIL) is difficult to implement in resource-constrained settings. We hypothesized that high-risk human papillomavirus (hrHPV) testing followed by immediate cryotherapy of women with hrHPV (HPV screen-and-treat) may improve outcomes.

METHODS

Randomized, open-label, phase 2, multinational clinical trial enrolling women with human immunodeficiency virus (HIV) age 18 or older with cervical hrHPV and having no cervical lesions or lesions appropriate for cryotherapy. Women were randomized to immediate cryotherapy (Arm A) or cytology-based screening (Arm B). For Arm A, cervical biopsies were obtained followed by cervical cryotherapy, and in Arm B, women with abnormal cytology underwent colposcopy followed by loop electroexcision procedure (LEEP) if bHSIL was detected. Women were followed through 30 months. The primary outcome was time to bHSIL detected from Month 6 through study completion.

RESULTS

In total, 288 women (145 in Arm A, 143 in Arm B) were randomized: median age 35 years, 84% on antiretroviral therapy, median CD4 501 cells/mm3. In Arm A, 39 (27%) of women had bHSIL at entry, and in Arm B, 88 (62%) had abnormal cytology, 22 (15%) were diagnosed with bHSIL, 12 (8%) underwent LEEP. In follow-up, 30 (21%) and 31 (22%) developed bHSIL; time to bHSIL was similar between arms (P=.94). The prevalence of hrHPV at Month 6 was similar between arms (61% and 70%, P=.13).

CONCLUSIONS

HPV test-and-treat was not associated with improved bHSIL outcomes as compared to cytology-based screening. More effective treatment options are required to improve outcomes from screen-and-treat programs.

CLINICAL TRIALS REGISTRATION

NCT01315363.

A novel cervical cancer screen-triage-treat demonstration project with HPV self-testing and thermal ablation for women in Malawi: Protocol for a single-arm prospective trial

Cervical cancer is the leading cause of cancer mortality among Malawian women, despite being preventable through screening and preventive therapy. In 2004, Malawi implemented a national screening program, using visual inspection with acetic acid (VIA) and cryotherapy, but its success has been limited due to equipment and human resources challenges. Since the development of that program, new technologies for screening and treatment that are less resource-intensive and more scalable have become available. GeneXpert systems provide fast, accurate HPV results and are increasingly available in low-income countries. Self-collection for human papillomavirus (HPV) testing is a validated method for screening and improves uptake. Thermal ablation provides an alternative ablative treatment that is simpler to use than cryotherapy and can be performed with portable devices. Meanwhile, urine HPV testing methods provide promising options for primary screening. We designed a single-arm prospective study to investigate a novel HPV screen-triage-treat strategy among 1250 women in Lilongwe, Malawi. Our proposed strategy consists of (1) Xpert HPV testing of self-collected samples, (2) VIA and colposcopy for HPV-positive women, and (3) thermal ablation for HPV-positive/ablation-eligible women. We will collect cervical biopsies, Pap smears, and endocervical samples to validate the HPV results and VIA/colposcopy findings against endpoints of high-grade cervical intraepithelial neoplasia or cancer (CIN2+). We will evaluate same-day completion of our algorithm, its performance in triaging women for treatment, and 24-week treatment efficacy of thermal ablation. We will also explore the performance of HPV and methylation tests in urine samples, as compared to provider- and self-collected cervicovaginal samples.

Human papillomavirus-based cervical precancer screening with visual inspection with acetic acid triage to achieve same-day treatments among women living with human immunodeficiency virus infection: test-of-concept study in Ibadan, Nigeria

Introduction

cervical precancer screening with same day treatment facilitates maximization of benefits of secondary prevention of cervical cancer. This is particularly important for women living with human immunodeficiency virus (WLHIV) infection because of their exceptional risk for cervical cancer. The availability of HIV programmes in low- and middle-income countries (LMICs) provide unique opportunity for possible introduction “human papillomavirus (HPV) screening followed by visual inspection after application of acetic acid (VIA) with same day treatment of eligible patients”. This study piloted this concept.

Methods

in this prospective, cohort study, 98 WLHIV had HPV and VIA screening for cervical precancer lesions in a HIV clinic in Nigeria. Participants positive to HPV and/or VIA had biopsies from the visible lesions or quadrant of transformation zone. Participants positive to VIA and/or HPV16 or HPV18/45 had same-day thermal ablation treatment and the number of cases documented. The HPV, VIA and scenario of HPV followed by VIA results were compared with histologically confirmed cervical lesion grade 2 or worse statistically.

Results

same day treatment was achieved in 95.0% of eligible cases. Statistically, sensitivity and specificity of VIA was 25.0% and 50.0% and HPV had 95.5% and 75.0%, respectively. In the HPV screening with VIA triage, sensitivity dropped to 45.5% but specificity improved to 100.0%.

Conclusion

triaging HPV positive test with VIA for same-day treatment in cervical precancer screening among PLWHIV looks feasible. The improved specificity will reduce the overtreatment rate, loss to follow-up associated with repeat clinic visits and improve completion of continuum of care.

Xpert HPV as a Screening Tool for Anal Histologic High-Grade Squamous Intraepithelial Lesions in Women Living With HIV

BACKGROUND

Women living with HIV (WLWH) experience high rates of anal cancer. Screening using anal cytology, high-resolution anoscopy (HRA) with biopsies, can histologically diagnose anal cancer precursors called high-grade squamous intraepithelial lesions (HSIL). The low specificity of screening using anal cytology results in HRA referral for many WLWH without HSIL. Screening using high-risk human papillomavirus (HR-HPV) may improve specificity.

METHODS

Two hundred seven WLWH (63% non-Hispanic black) were screened for anal histologic HSIL (hHSIL) using cytology, HRA-guided biopsies, and Xpert HPV. Xpert performance for predicting anal hHSIL was compared with that of cytology. Usng Xpert 5 HPV genotypic results and accompanying cycle thresholds, receiver operator characteristic curve and recursive partitioning analyses were used to create predictive models for hHSIL.

RESULTS

The performance of Xpert to predict hHSIL was not different from that of cytology with a sensitivity (Sn) of 89% and specificity (Sp) of 49%. Interpretation of Xpert was modified using genotypic results and receiver operator characteristic curve analysis, which produced a screen with an Sn and Sp of 75% and 84% for hHSIL, respectively. Another reinterpretation of Xpert was created using recursive partitioning and cycle thresholds, which predicted hHSIL with an Sn and Sp of 75% and 86%, respectively. The detection of HPV-16 was highly predictive of hHSIL in all analyses. These modified screening tests would reduce HRA referral in this population by almost half compared with anal cytology.

CONCLUSIONS

Xpert HPV is an alternative to anal cytology to screen for anal HSIL and can be optimized to reduce the number of unnecessary HRAs performed in WLWH.

A simple and rapid diagnostic method for 13 types of high-risk human papillomavirus (HR-HPV) detection using CRISPR-Cas12a technology

Cervical carcinoma is the second most common cancer in women worldwide with greater than 99% of the cases caused by human papillomaviruses (HPVs). Early detection of HPVs especially the high risk types (HR-HPVs) are essential to prevent the disease progression. The existing methods for HPV detection, such as qPCR are of high sensitivity and specificity, but the need for expensive machinery and well-trained personnel slow down the disease detection. The emerging Cas12a-based method presents a new technique for nucleic acid detection. However, it is time-consuming and labor-intensive when used for HPV detection, as several reactions are required in order to identify multiple HPV infections. We herein present a non-genotyping method for 13 types of HR-HPV detection in a single reaction by combining the isothermal recombinase polymerase amplification (RPA) method with CRISPR-Cas12a technology. The result could be achieved in 35 min with high sensitivity (500 copies per reaction). This assay represents great advances for the application of RPA-Cas12a system and holds a great potential to address the key challenges facing the HPV diagnostics.

Selecting human papillomavirus genotypes to optimize the performance of screening tests among South African women

Human papillomavirus (HPV) testing is highly sensitive compared to cytology, with the trade-off of being less specific. We investigated whether select combinations of HPV genotypes, ascertained by Linear Array (LA) and Xpert HPV (GX), can optimize sensitivity/specificity trade-offs to detect high-grade cervical intraepithelial neoplasia (CIN2+). In a study in Cape Town, South Africa, 586 women living without and 535 living with HIV, aged 30-65 years, were recruited. Each woman underwent a pelvic exam to collect cervical samples (tested by LA and GX for 14 high-risk HPV genotypes) and underwent colposcopy with histological sampling to determine CIN2+. In multivariable logistic regression of LA results, only HPV genotypes 16, 18, 31, 33, 35, 52, 58 were significantly associated with CIN2+ (P < .05). Xpert includes these seven types along with HPV 45 within three of the test's five channels and we defined these eight types as restricted genotyping (ie 16, 18, 31, 33, 35, 45, 52, 58). Full genotyping was defined as all 14 high-risk types. Sensitivity estimates for full genotyping using LA were similar to that of restricted genotyping: 83.9% (full) vs 79.0% (restricted) in women without HIV and 93.0% (full) vs 88.9% (restricted) in women living with HIV. Specificity estimates improved for restricted vs full genotyping: 87.4% (full) vs 90.8% (restricted) in women without HIV and 63.7% (full) vs 71.4% (restricted) in women living with HIV. To optimize the performance of HPV testing for cervical cancer screening in high-burden, under-resourced settings like South Africa, only HPV 16, 18, 31, 33, 35, 45, 52, 58 could be included to define screen-positive. We recommend the inclusion of HPV45 for its known link to adenocarcinoma.

Cervical human papillomavirus DNA detection in women living with HIV and HIV-uninfected women living in Limbe, Cameroon

BACKGROUND

There are limited data on cervical HPV prevalence in Cameroon and none from its Anglophone region. We investigated cervical HPV prevalence in HIV-uninfected (HIV[-]) and HIV-infected (WLWH) women living in the region.

METHODS

A convenience sample of consecutively recruited HIV[-] women (n = 295) and women living with HIV (WLWH) (n = 560) attending the Limbé Regional Hospital were enrolled into a cervical screening study. Women underwent screening that included HPV testing of self-collected and provider-collected specimens. We calculated the HPV prevalence by HIV status, overall and stratified by age, and among WLWH, stratified by CD4 counts. We compared the concordance for the detection of HPV between self- and provider-collected specimens.

RESULTS

Crude HPV prevalence was 21.69 % (95 % confidence interval [95 %CI] = 17.21-26.48 %) for HIV[-] women and 46.43 % (95 %CI = 42.24-50.66 %) for WLWH (p < 0.001). Among WLWH, older age (p_trend = 0.01) and higher CD4 counts (p_trend = 0.007) were associated with lower HPV prevalence. There was a good-to-excellent agreement for HPV detection between specimens, and self-collected were more likely than provider-collected specimens to test HPV positive, for all women and stratified by HIV status.

CONCLUSIONS

HIV-related immunosuppression was a risk factor for HPV prevalence in this population. HPV testing of self-collected specimens appeared to be less specific than HPV testing of provider-collected specimens.

Advances in technologies for cervical cancer detection in low-resource settings

Introduction: Cervical cancer mortality rates remain high in low- and middle-income countries (LMICs) and other medically underserved areas due to challenges with implementation and sustainability of routine screening, accurate diagnosis, and early treatment of preinvasive lesions. Areas covered: In this review, we first discuss the standard of care for cervical cancer screening and diagnosis in high- and low-resource settings, biomarkers that correlate to cervical precancer and cancer, and needs for new tests. We review technologies for screening and diagnosis with a focus on tests that are already in use in LMICs or have the potential to be adapted for use in LMICs. Finally, we provide perspectives on the next five years of technology development for improved cervical cancer screening and diagnosis in LMICs. Expert opinion: Innovation toward improved molecular and imaging tests is needed to enable effective, affordable see-and-treat approaches to detect and treat cervical precancer in a single visit. Current molecular tests remain too complex and/or costly for widespread use. Especially with imaging tests, decision support may improve performance of new technologies.

Synergistically enhanced colorimetric molecular detection using smart cup: a case for instrument-free HPV-associated cancer screening

Rationale: Early and accurate detection of disease is crucial for its prevention, identification, and treatment. However, most of disease diagnostics is still limited in clinical laboratories due to the need of complicated instruments and professional personnel. Herein, we reported a smartphone-based synergistically enhanced colorimetric method for molecular diagnostics in our point of care (POC) smart cup platform. Methods: A disposable microfluidic chip was developed for colorimetric loop-mediated isothermal amplification (LAMP) detection of multiple HPV DNA in our POC smart cup platform. The colorimetric detection takes advantage of synergistic effect of PPi4- and H+ ions, two byproducts of LAMP reaction. Color signal of LAMP assay was recorded and analyzed by our custom Android app (dubbed "Hue Analyzer"). Results: Our method not only significantly improves colorimetric readout, but also provides a 10-fold increase in detection sensitivity. It has been successfully applied for HPV-associated cancer screening with spiked saliva and clinical swab samples. Conclusion: The proposed POC diagnostic platform is completely compatible with other nucleic acid biomarkers and has great potential for personalized health monitoring and disease prevention.

HPV-based cervical screening: Rationale, expectations and future perspectives of the new Dutch screening programme

Based on scientific data showing that HPV testing provides better protection against cervical precancer and cancer than cytology, in 2011 the Dutch Health Council advised the Minister of Welfare, Health and Sports to replace cytology by HPV testing in the Dutch population-based screening programme. After a successful evaluation of the feasibility of HPV-based screening in 2014, primary HPV testing for cervical screening was implemented in 2017. The Netherlands has been one of the first countries worldwide to implement nationwide HPV-based screening and its experience with the new programme is therefore followed with great interest. In this manuscript, we present an overview of the studies that were instrumental in the choice of HPV assay and triage strategy, the adjustment of screening starting and exit ages and intervals, and the implementation of HPV self-sampling. Finally, we review the cost-effectiveness of the proposed new screening algorithm and we explore future perspectives. The rationale behind the new Dutch HPV-based screening programme, which is based on risk management, could serve as a guidance to other countries that are planning to implement HPV-based screening in the near future.

Health impact of delayed implementation of cervical cancer screening programs in India: A modeling analysis

India has the highest burden of cervical cancer in the world. To estimate the consequences of delaying implementation of organized cervical cancer screening, we projected the avertable burden of disease under different implementation scenarios of a screening program. We used an individual‐based microsimulation model of human papillomavirus (HPV) infection and cervical cancer calibrated to epidemiologic data from India to project age‐specific cancer incidence and mortality reductions associated with screening (once‐in‐a‐lifetime among women aged 30–34 years) with one‐visit visual inspection with acetic acid (VIA) and one‐ and two‐visit HPV DNA testing. We then applied these reductions to a population model to project the lifetime cervical cancer cases and deaths averted under different implementation scenarios taking place from 2017 to 2026: (1) immediate implementation of screening with currently available screening tests (one‐visit VIA, two‐visit HPV testing); (2) immediate implementation of screening with currently available screening tests, with a switch to point‐of‐care one‐visit HPV testing in 5 years; and (3) 5‐year delayed implementation of screening with current screening tests or point‐of‐care HPV testing. Immediate implementation of two‐visit HPV testing with a switch to one‐visit HPV testing averted 574,100 cases and 382,500 deaths over the lifetimes of 81.4 million 30‐ to 34‐year‐old women screened once between 2017 and 2026. Delayed implementation with a one‐visit HPV test averted 209,300 cases and 139,100 deaths. Delaying implementation of screening programs in high‐burden settings will result in substantial morbidity and mortality among women beyond the age for adolescent HPV vaccination.

What's new?

Nearly one‐quarter of cervical cancer cases worldwide occur in India. Nonetheless, while the disease can be prevented through screening for precancerous lesions, very few Indian women receive Pap tests. Here, the authors estimated cervical cancer burden in India assuming different screening program implementation scenarios, including immediate implementation with both one‐visit VIA and two‐visit human papillomavirus (HPV) testing and delayed implementation with a one‐visit HPV test. Models showed that immediate implementation of two‐visit HPV testing averted more than double the number of cases and deaths from cervical cancer among 30‐ to 34‐year‐old women compared with delayed implementation with one‐visit HPV testing.

Protocol for the study of cervical cancer screening technologies in HIV-infected women living in Rwanda

INTRODUCTION

The optimal method(s) for screening HIV-infected women, especially for those living in sub-Saharan Africa, for cervical precancer and early cancer has yet to be established.

METHODS AND ANALYSIS

A convenience sample of >5000 Rwandan women, ages 30-54 years and living with HIV infection, is being consented and enroled into a cross-sectional study of cervical cancer screening strategies. Participants are completing an administered short risk factor questionnaire and being screened for high-risk human papillomavirus (hrHPV) using the Xpert HPV assay (Cepheid, Sunnyvale, California, USA), unaided visual inspection after acetic acid (VIA) and aided VIA using the Enhanced Visual Assessment (EVA) system (Mobile ODT, Tel Aviv, Israel). Women positive for hrHPV and/or by unaided VIA undergo colposcopy, which includes the collection of two cervical specimens prior to undergoing a four-quadrant microbiopsy protocol. The colposcopy-collected specimens are being tested by dual immunocytochemical staining for p16INK4a and Ki-67 (CINtec PLUS Cytology, Ventana, Tucson, Arizona, USA) and for E6 or E7 oncoprotein for 8 hrHPV genotypes (HPV16, 18, 31, 33, 35, 45, 52 and 58) using the next-generation AV Avantage hrHPV E6/E7 test (Arbor Vita Corporation, Freemont, California, USA). Women with a local pathology diagnosis of cervical intraepithelial neoplasia grade 2 (CIN2) or more severe (CIN2+) or pathology review diagnosis of CIN grade three or more severe (CIN3+) will receive treatment. Clinical performance and cost-effectiveness (eg, sensitivity, specificity and predictive values) of different screening strategies and algorithms will be evaluated.

ETHICS AND DISSEMINATION

The protocol was approved by local and institutional review boards for human subjects research. At the completion of the study, results will be disseminated to the scientific community through peer-reviewed publication and to the Rwandan stakeholders through an external advisory panel.

Interest of cytology combined with Xpert® HPV and Anyplex® II HPV28 Detection human papillomavirus (HPV) typing: differential profiles of anal and cervical HPV lesions in HIV-infected patients on antiretroviral therapy

OBJECTIVES

The aim of the study was to assess the interest to combine cytological examination and human papillomavirus (HPV) typing of anal and cervical Papanicolaou (Pap) smears of HIV-infected patients on combination antiretroviral therapy (cART), to evaluate whether differences in prevalence exist between anal and cervical squamous intraepithelial lesions in patients with high-risk oncogenic HPV infection.

METHODS

Anal and/or cervical Pap smears were obtained by anoscopy and/or colposcopy in 238 subjects recruited consecutively in 2015: anal smears were obtained from 48 male and female patients [42 men; 35 men who have sex with men (MSM)] and cervical smears from 190 female patients. Cytological Bethesda classification was coupled with HPV typing. HPV typing was performed, on the same smears, using the Xpert^® HPV Assay, which detects only high-risk HPV (hrHPV), and the Anyplex^® II HPV28 Detection assay, which detects hrHPV and low-risk (lr) HPV.

RESULTS

Our data showed clear-cut differences between the anal and cervical samples. Compared with the cervical samples, the anal samples exhibited (1) more numerous cytological lesions, which were histologically proven; (2) a higher hrHPV infection prevalence; (3) a higher prevalence of multiple hrHPV coinfections whatever HPV typing kit was used; (4) a predominance of HPV16 and HPV18/45 types. Overall, there was an almost perfect agreement between the two HPV typing assays (absolute agreement = 90.3%).

CONCLUSIONS

Co-testing consisting of cytology and HPV typing is a useful screening tool in the HIV-infected population on cART. It allows detection of prevalence differences between anal and cervical HPV-related lesions. As recently recommended, anal examination should be regularly performed especially in HIV-infected MSM but also in HIV-infected women with genital hrHPV lesions.

Comparison of the Cepheid Xpert HPV test and the HC2 High-Risk HPV DNA Test for detection of high-risk HPV infection in cervical smear samples in SurePath preservative fluid

Purpose. Cytological and histological cervical screening methods for human papillomavirus may be subjective. Current guidelines recommend the use of direct human papillomavirus screening by molecular methods in conjunction with cytology for the detection of high-risk human papillomavirus types with carcinogenic potential. In this study, we compared the performance of the molecular Cepheid Xpert HPV test to the FDA-approved HC2 High-Risk HPV DNA Test on samples from patients presenting for cervical screening, regardless of the cytology results, in which cervical cell samples were originally collected for Papanicolaou (Pap) smear specimens in Becton Dickinson (BD) SurePath preservative fluid.Methodology. Cervical cells were obtained for Pap smear specimens from 343 women attending Qatif Central Hospital in Saudi Arabia for cervical cancer screening using a Cytobrush Plus GT and immersed in BD SurePath preservative fluid in BD SurePath collection vials. The study was carried out between December 2015 and July 2016.Results. The Xpert HPV test was positive in 27 (7.9 %) of the samples. The HC2 High-Risk HPV DNA Test was positive in 32 (9.3 %) of the samples. The most common HPV types according to the Xpert HPV test were HPV other types, either alone (n=15) or in combination with HPV16 (n=3). The overall concordance rate between the tests was 98.5 %. The positive concordance was 84.4 %.Conclusion. The Xpert HPV test is convenient to use on cervical cell samples collected for Pap smear specimens in BD SurePath preservative fluid within an hour and is a viable alternative to the HC2 High-Risk HPV DNA Test for HPV testing.

Advancing prevention of sexually transmitted infections through point-of-care testing: target product profiles and landscape analysis

OBJECTIVES

Advancing the field of point-of-care testing (POCT) for STIs can rapidly and substantially improve STI control and prevention by providing targeted, essential STI services (case detection and screening). POCT enables definitive diagnosis and appropriate treatment in a single visit and home and community-based testing.

METHODS

Since 2014, the WHO Department of Reproductive Health and Research, in collaboration with technical partners, has completed four landscape analyses of promising diagnostics for use at or near the point of patient care to detect syphilis, Neisseria gonorrhoeae, Chlamydia trachomatis, Trichomonas vaginalis and the human papillomavirus. The analyses comprised a literature review and interviews. Two International Technical Consultations on STI POCTs (2014 and 2015) resulted in the development of target product profiles (TPP). Experts in STI microbiology, laboratory diagnostics, clinical management, public health and epidemiology participated in the consultations with representation from all WHO regions.

RESULTS

The landscape analysis identified diagnostic tests that are either available on the market, to be released in the near future or in the pipeline. The TPPs specify 28 analytical and operational characteristics of POCTs for use in different populations for surveillance, screening and case management. None of the tests that were identified in the landscape analysis met all of the targets of the TPPs.

CONCLUSION

More efforts of the global health community are needed to accelerate access to affordable quality-assured STI POCTs, particularly in low- and middle-income countries, by supporting the development of new diagnostic platforms as well as strengthening the validation and implementation of existing diagnostics according to internationally endorsed standards and the best available evidence.

A systematic review and meta-analysis of studies evaluating the performance of point-of-care tests for human papillomavirus screening

BACKGROUND

High-risk human papillomavirus (HPV) is a necessary cause of high-grade cervical intraepithelial neoplasia (grade 2 or higher, CIN2+). Simplified and rapid HPV DNA assays designed for use in resource-limited settings have recently become available.

METHODS

We performed a systematic review and meta-analysis by searching Medline, Embase, Global Health and CINAHL databases for studies from 1 January 2004 to 25 February 2017 that reported the performance of careHPV or OncoE6 for the detection of histological CIN2+ in cervical cancer screening. We used bivariate models to estimate pooled sensitivity and specificity for CIN2+ and CIN3+.

RESULTS

A total of 29 657 women were included from seven studies evaluating the performance of careHPV for the detection of CIN2+ and four studies among 27 845 women for the detection of CIN3+. The pooled prevalence for CIN2+ and CIN3+ was 2.3% and 1.1%, respectively. careHPV had sensitivity and specificity of 88.1% (95% CI 81.4 to 92.7) and 83.7% (95% CI 74.9 to 89.8), respectively, for CIN2+ and 90.3% (95% CI 83.4 to 94.5) and 85.3% (95% CI 73.1 to 92.5), respectively, for CIN3+, using clinician-collected cervical specimen. The corresponding pooled estimates using self-collected vaginal swabs were 73.6% (95% CI 64.9 to 80.8) and 88.0% (95% CI 79.1 to 93.5) for CIN2+ and 75.2% (95% CI 66.8 to 82.0) and 90.6% (95% CI 83.4 to 94.9) for CIN3+. Two studies using OncoE6 reported sensitivity and specificity ranging from 31.3% to 42.4% and 99.1%-99.4% for CIN2+, and 53.5% and 98.9% for CIN3+ for one study.

CONCLUSION

CareHPV has good sensitivity and specificity for the detection of CIN2+ and CIN3+, but sensitivity was lower using self-collected vaginal samples. The specificity is lower in high HPV prevalence populations such as women living with HIV. OncoE6 assay warrants further evaluation.

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.

Attitude to Human Papillomavirus Deoxyribonucleic Acid-Based Cervical Cancer Screening in Antenatal Care in Nigeria: A Qualitative Study

OBJECTIVES

Human papillomavirus (HPV) deoxyribonucleic acid (DNA)-based testing is increasingly used for cervical cancer screening in developed countries, but the best approach to utilizing it in low- and middle-income countries (LMIC) is unclear. Incorporation of HPV DNA-based testing into routine antenatal care (ANC) is a potential yet poorly explored strategy for cervical cancer screening in LMIC. We explored the attitude of health care workers and pregnant women to the incorporation of HPV DNA-based tests into routine ANC in Nigeria.

METHODS

We conducted nine focus group discussions with 82 pregnant women and 13 in-depth interviews with obstetricians and midwives at four health care facilities in Abuja, Nigeria. We used qualitative content analysis to analyze the data and the theory of planned behavior as a theoretical framework to examine the responses.

RESULTS

Pregnant women expressed a favorable attitude toward HPV DNA testing for cervical cancer screening as part of routine ANC. Acceptability of this approach was motivated by the expected benefits from early detection and treatment of cervical cancer. The factors most commonly cited as likely to influence acceptability and uptake of HPV DNA-based tests are recommendations by their care providers and mandating testing as part of ANC services. Discussants mentioned lack of awareness and affordability as factors that may inhibit uptake of HPV DNA-based cervical cancer screening. Midwives expressed concerns about the safety of sampling procedure in pregnancy, while obstetricians fully support the integration of HPV DNA-based testing into routine ANC.

CONCLUSION

Our results show that incorporating HPV DN-based cervical cancer screening into routine ANC is acceptable to pregnant women and health care providers. Making the test affordable and educating health care workers on its efficacy and safety if performed during ANC will enhance their willingness to recommend it and increase its uptake.

Prevalence of Anal Human Papillomavirus (HPV) and Performance of Cepheid Xpert and Hybrid Capture 2 (hc2) HPV Assays in South African HIV-Infected Women

OBJECTIVES

This study investigated anal high-risk HPV (HR-HPV) prevalence in HIV-infected women using the Cepheid Xpert HPV assay and compares its performance with that of Hybrid Capture-2 (hc2).

METHODS

A total of 199 HIV-infected women were recruited from Helen Joseph Hospital, Johannesburg. Stored ThinPrep anal swabs that had previously been tested using hc2 were tested for HPV using Xpert.

RESULTS

The HR-HPV prevalence by Xpert was 40.8% and similar to hc2 (41.8%) with overall agreement of 86.7%; Cohen's kappa 0.73 (95% CI 0.63-0.82). High grade squamous intraepithelial lesions (HSIL) was associated with increasing number of multiple HPV infection (P < .001). Xpert and hc2 were similarly sensitive (77.4% and 77.4%, respectively) and specific (66.1% and 64.8% respectively) for HSIL detection. HPV16 (OR: 14.0, 95% CI: 3.9-48.0, P < .0001), HPV39/68/56/66 (OR: 4.1, 95% CI: 1.4-12, P = .01) and HPV51/59 (OR: 2.8, 95% CI: 1.1-7.6, P = .04) were independently associated with anal HSIL.

CONCLUSIONS

Xpert HPV typing is a promising anal screening test in HIV-infected women that performs similarly to hc2.

Accuracy of self-collected vaginal dry swabs using the Xpert human papillomavirus assay

BACKGROUND

Polymerase chain reaction-based Xpert human papillomavirus (HPV) assay is a rapid test that detects high-risk HPV (hrHPV) infection. This point-of-care test is usually performed by collecting a cervical specimen in a vial of PreservCyt® transport medium. We compared HPV test positivity and accuracy between self-collected sample with a dry swab (s-DRY) versus physician-collected cervical sampling using a broom like brush and immediate immersion in PreservCyt (dr-WET).

METHODS

In this cross-sectional study, we recruited 150 women ≥ 18 years old attending the colposcopy clinic in the University Hospital of Geneva. Each participant first self-collected a vaginal sample using a dry swab and then the physician collected a cervical specimen in PreservCyt. HPV analysis was performed with Xpert. Part of the PreservCyt-collected sample was used for hrHPV detection with the cobas® HPV test. HPV test positivity and performance of the two collection methods was compared.

RESULTS

HPV positivity was 49.1% for s-DRY, 41.8% for dr-WET and 46.2% for cobas. Good agreement was found between s-DRY and dr-WET samples (kappa±Standard error (SE) = 0.64±0.09,), particularly for low-grade squamous intraepithelial lesions (LSIL+) (kappa±SE = 0.80±0.17). Excellent agreement was found between the two samples for HPV16 detection in general (kappa±SE = 0.91±0.09) and among LSIL+ lesions (kappa±SE = 1.00±0.17). Sensitivities and specificities were, respectively, 84.2% and 47.1%(s-DRY), 73.1% and 58.7%. (dr-WET) and 77.8% and 45.7% (cobas) for CIN2+ detection. The median delay between sampling and HPV analysis was 7 days for the Xpert HPV assay and 19 days for cobas. There were 36 (24.0%) invalid results among s-DRY samples and 4 (2.7%) among dr-WET (p = 0.001). Invalid results happened due to the long interval between collection and analysis.

CONCLUSION

Self-collected vaginal dry swabs are a valid alternative to collecting cervical samples in PreservCyt solution for HPV testing with the Xpert HPV assay.

IMPACT

HPV self-collection with dry cotton swabs might assist in the implementation of an effective screening strategy in developing countries.

TRIAL REGISTRATION

International Standard Randomized Controlled Trial Number Registry ISRCTN83050913.

Cervical cancer screening in a low-resource setting: a pilot study on an HPV-based screen-and-treat approach

Cervical cancer (CC) is the leading cause of cancer‐related death among women in sub‐Saharan Africa, primarily because of limited access to effective screening and preventive treatment. Our aim was to assess the feasibility of a human papillomavirus (HPV)‐based CC screen‐and‐treat approach in a low‐resource context. We recruited 1012 women aged 30–49 years through a CC screening campaign conducted in the District Hospital of Dschang, Cameroon. Participants performed HPV self‐sampling, which was tested for high‐risk HPV (HR‐HPV) DNA using the point‐of‐care Xpert HPV assay. All HPV‐positive women were invited for visual inspection with acetic acid and Lugol's iodine (VIA/VILI) to exclude CC or enable triage. A cervical sample for histological analysis was also collected. Women positive for HPV 16/18/45 and for other HR‐HPV with pathological VIA/VILI were selected to undergo treatment with thermocoagulation. The HPV prevalence in the study population was 18.5% (n = 187); of these cases, 20 (10.6%), 42 (22.3%) and 140 (74.9%) were positive for HPV16, HPV18/45 and other HR‐HPV types, respectively. Overall, 107/185 (57.8%) VIA/VILI examinations were classified as pathological and 78 (42.2%) as normal. Women positive for HPV16/18/45 were 4.2 times more likely to harbor cervical intraepithelial neoplasia grade 2 or worse (CIN2+) than those with other HPV types. The specificity of HPV 16/18/45 genotypes for detection of high‐grade lesions among HR‐HPV positive women was higher than that of VIA/VILI in all age groups. The sensitivity and specificity of VIA/VILI in detecting CIN2+ among HPV positive women were 80% and 44%, respectively. Overall, 110/121 screen‐positive women (90.9%) were eligible for, and were treated with, thermocoagulation. An HPV‐based screen‐and‐treat approach is feasible in a low‐resource context and may contribute to improving the effectiveness of CC prevention programs. Immediate thermocoagulation treatment for women who are HPV16‐ and/or HPV18/45‐positive is a practical approach for the treatment of CIN2+. The combination of HPV‐testing and VIA/VILI for CC screening might reduce overtreatment.

HPV prevalence in women attending cervical screening in rural Malawi using the cartridge-based Xpert® HPV assay

BACKGROUND AND OBJECTIVES

Early experience with Cepheid Xpert^® HPV assay (Xpert^® HPV) suggests that its quick turnaround time and ease of application might make it a relevant contender for routine use in low and middle income countries (LMICs). In the context of a cervical screening service in rural Malawi, we aimed to assess practicalities of local laboratory testing with Xpert^® HPV and provide preliminary high-risk HPV (HR-HPV) prevalence data.

STUDY DESIGN

Liquid-based cytology (LBC) specimens were collected from women attending cervical screening clinics in Nkhoma, Malawi. Xpert^® HPV testing was carried out according to manufacturer's instructions. Partial genotyping results were obtained immediately (HPV 16, 18/45 and HR-HPV 'other'). Review of individual channel data provided further breakdown of other HR-HPV types into HPV 31 and related; HPV 51/59 and HPV 39 and related.

RESULTS

Valid HR-HPV results were obtained from 750/763 samples. Most samples were from previously unscreened women, with 92.3% aged between 20 and 60 years. Overall HR-HPV positivity was 19.9%, with HR-HPV 'other' being more than twice as frequent as HPV 16 or HPV 18/45 and HPV 31-related (HPV 31, 33, 35, 52 or 58) most prevalent. Known HIV status was low (7.3%), but HR-HPV positivity in this group was much higher (43.4%).

CONCLUSIONS

HR-HPV testing using Xpert^® HPV was practical in a small rural laboratory. The rapid turnaround (within 2h) could facilitate a 'see and treat' programme. Partial genotyping allows assessment of risk beyond HPV 16/18. The high prevalence of HPV 31 and related types warrants further investigation.

[Molecular diagnosis of human papillomaviruses (HPV): What test(s) in clinical practice?]

Prescription of an HPV test in practice will enable the clinician to optimize the monitoring and the management of patients, especially in the context of cervical cancer screening. Numerous HPV tests are available that present different analytical and clinical sensitivity and specificity. International recommendations on clinical performance of HPV tests used for cervical cancer screening have been published by a group of experts, and tests that meet these performance criteria should be used. Apart from the HPV detection kit, the whole circuit from sampling to report of the results must be considered. This implies that the pre-analytical (sampling, quality of sample collection medium, storage condition and sample transportation…) and post-analytical steps (quality of result reporting, providing expert advices…) are also standardized. For this purpose, medical-biology laboratories are subjected to a COFRAC certification, as defined by the international standard ISO 15189 providing quality criteria for any clinical laboratory test and HPV test in particular.

Performance of a Cartridge-Based Assay for Detection of Clinically Significant Human Papillomavirus (HPV) Infection: Lessons from VALGENT (Validation of HPV Genotyping Tests)

The Validation of Human Papillomavirus (HPV) Genotyping Tests (VALGENT) studies offer an opportunity to clinically validate HPV assays for use in primary screening for cervical cancer and also provide a framework for the comparison of analytical and type-specific performance. Through VALGENT, we assessed the performance of the cartridge-based Xpert HPV assay (Xpert HPV), which detects 14 high-risk (HR) types and resolves HPV16 and HPV18/45. Samples from women attending the United Kingdom cervical screening program enriched with cytologically abnormal samples were collated. All had been previously tested by a clinically validated standard comparator test (SCT), the GP5+/6+ enzyme immunoassay (EIA). The clinical sensitivity and specificity of the Xpert HPV for the detection of cervical intraepithelial neoplasia grade 2 or higher (CIN2+) and CIN3+ relative to those of the SCT were assessed as were the inter- and intralaboratory reproducibilities according to international criteria for test validation. Type concordance for HPV16 and HPV18/45 between the Xpert HPV and the SCT was also analyzed. The Xpert HPV detected 94% of CIN2+ and 98% of CIN3+ lesions among all screened women and 90% of CIN2+ and 96% of CIN3+ lesions in women 30 years and older. The specificity for CIN1 or less (≤CIN1) was 83% (95% confidence interval [CI], 80 to 85%) in all women and 88% (95% CI, 86 to 91%) in women 30 years and older. Inter- and intralaboratory agreements for the Xpert HPV were 98% and 97%, respectively. The kappa agreements for HPV16 and HPV18/45 between the clinically validated reference test (GP5+/6+ LMNX) and the Xpert HPV were 0.92 and 0.91, respectively. The clinical performance and reproducibility of the Xpert HPV are comparable to those of well-established HPV assays and fulfill the criteria for use in primary cervical cancer screening.

Field Evaluation of Xpert HPV Point-of-Care Test for Detection of Human Papillomavirus Infection by Use of Self-Collected Vaginal and Clinician-Collected Cervical Specimens

The World Health Organization has recommended that testing for high-risk human papillomavirus (HPV) (hrHPV) infection be incorporated into cervical screening programs in all settings worldwide. In many high-burden, low-income countries, it will not be feasible to achieve high cervical screening coverage using hrHPV assays that require clinician-collected samples. We conducted the first evaluation of self-collected vaginal specimens compared with clinician-collected cervical specimens for the detection of hrHPV infection using the Xpert HPV test. Women aged 30 to 54 years attending two well-woman clinics in Papua New Guinea were invited to participate and provided self-collected vaginal and clinician-collected cervical cytobrush specimens. Both specimen types were tested at the point of care by using the Xpert HPV test. Women were given their cervical test result the same day. Those with a positive hrHPV test and positive examination upon visual inspection of the cervix with acetic acid were offered same-day cervical cryotherapy. A total of 1,005 women were enrolled, with 124 (12.3%; 95% confidence interval [CI], 10.3%, 14.4%) being positive for any hrHPV infection. There was a 99.4% overall percent agreement (OPA) between vaginal and cervical tests for HPV-16 (95% CI, 98.9%, 99.9%), a 98.5% OPA for HPV-18/45 (95% CI, 97.7%, 99.3%), a 94.4% OPA for other hrHPV infections (95% CI, 92.9%, 95.9%), and a 93.4% OPA for all hrHPV types combined (95% CI, 91.8%, 95.0%). Self-collected vaginal specimens had excellent agreement with clinician-collected cervical specimens for the detection of hrHPV infection using the Xpert HPV test. This approach provides for the first time an opportunity to incorporate point-of-care hrHPV testing into clinical cervical screening algorithms in high-burden, low-income settings.

Xpert human papillomavirus test is a promising cervical cancer screening test for HIV-seropositive women

This study investigated the performance of Cepheid Xpert human papillomavirus (HPV) assay in South African human immunodeficiency virus (HIV)-infected women and compared its performance with that of hybrid capture-2 (hc2). Methods: Stored cervical specimens from HIV-infected women that had previously been tested using hc2 were tested using Xpert. Results: The overall HR-HPV prevalence was found to be 62.0% (720/1161) by Xpert and 61.2% (711/1161) by hc2. 13.6% (158/1161) were HPV16 positive, 18.8% (218/1161) were HPV18/45, 37.3% (434/1161) were HPV31/33/35/52/58, 12.7% (147/1161) were HPV51/59 and 23.3% (270/1161) were HPV39/68/56/66. Overall agreement with hc2 was 90%; Cohen’s kappa was 0.78 (95% CI 0.74–0.82) indicating substantial agreement. Detection of HPV16, HPV18/45, and HPV31/33/35/52/58 were independently associated with cervical intraepithelial neoplasia (CIN)−2+ (P<0.0001 for each); while HPV51/59 and HPV39/68/56/66 were not. Women infected with HPV16, HPV18/45 or HPV31/33/35/52/58 were found to have significantly higher amounts of HPV DNA detected for those with CIN2+ compared to those without CIN2+, P<0.0001 for each. Xpert and hc2 were similarly sensitive (88.3% and 91.5%, respectively) and specific (48.4% and 51.0%) for CIN2+ and CIN3 (sensitivity: 95.8% and 97.9%; specificity: 41.4% and 42.8%). Conclusions: Xpert is a promising screening test in HIV-infected women that performs similarly to hc2.

VALGENT: A protocol for clinical validation of human papillomavirus assays

BACKGROUND

Testing for high-risk HPV is more effective in primary cervical cancer screening than the cytological examination of a Pap smear. Separate genotyping may be useful for triage in both HPV-based and cytology-based screening. Only clinically validated tests should be used in clinical practice.

OBJECTIVES

VALGENT is a study framework for test comparison and validation of HPV assays in general and HPV genotyping tests in particular according to clinically relevant outcomes and for clinical applications endorsed by scientific evidence.

STUDY DESIGN

VALGENT involves the collation of fresh or archived cervical cell specimen from women attending routine screening supplemented with cytologically abnormal samples. Multiple aliquots of residual material are sent from a central laboratory to participating laboratories for testing with novel HPV assays with limited, extended or full genotyping capacity. Outcomes are derived from screening and pathology registries. Each VALGENT panel includes an assay already validated for screening. A series of accuracy and concordance statistics were generated.

RESULTS

Currently, two VALGENT study rounds, originated from laboratories in Antwerp (Belgium) and Edinburgh (Scotland), were completed. Two new assays (G5+/6+ PCR-LMNX and Xpert HPV) were validated for screening by showing similar accuracy for cervical precancer as the standard comparator test. For two other tests (BD Onclarity, PapilloCheck) validation was confirmed. Inter-test agreement was high although certain type-specific discordances were observed which warrant further analysis.

CONCLUSION

VALGENT extends current guidelines for high-risk HPV test validation in cervical cancer screening and has produced a large study resource for test comparison. More robust procedures of sample selection and handling and integration with the global WHO reference laboratory network focusing on analytical accuracy, may result in the generation of an international standard and a formalized system for clinical validation of HPV assays and quality control in HPV-based screening.

HPV-FASTER: broadening the scope for prevention of HPV-related cancer

Human papillomavirus (HPV)-related screening technologies and HPV vaccination offer enormous potential for cancer prevention, notably prevention of cervical cancer. The effectiveness of these approaches is, however, suboptimal owing to limited implementation of screening programmes and restricted indications for HPV vaccination. Trials of HPV vaccination in women aged up to 55 years have shown almost 90% protection from cervical precancer caused by HPV16/18 among HPV16/18-DNA-negative women. We propose extending routine vaccination programmes to women of up to 30 years of age (and to the 45-50-year age groups in some settings), paired with at least one HPV-screening test at age 30 years or older. Expanding the indications for HPV vaccination and much greater use of HPV testing in screening programmes has the potential to accelerate the decline in cervical cancer incidence. Such a combined protocol would represent an attractive approach for many health-care systems, in particular, countries in Central and Eastern Europe, Latin America, Asia, and some more-developed parts of Africa. The role of vaccination in women aged >30 years and the optimal number of HPV-screening tests required in vaccinated women remain important research issues. Cost-effectiveness models will help determine the optimal combination of HPV vaccination and screening in public health programmes, and to estimate the effects of such approaches in different populations.

Performance of the Xpert HPV assay in women attending for cervical screening

Objectives

This study evaluated the Xpert HPV Assay in women attending screening in general practice by comparing Xpert with two established HPV tests, cytology and histology.

Methods

A prospective study in women aged 20–60 years attending screening in Bristol, Edinburgh and London using residual Preservcyt cytology samples. Sample order was randomised between Roche cobas4800 and Cepheid Xpert assays with Qiagen hc2 third.

Results

3408 cases were included in the primary analysis. Positivity for Xpert was 19.6%, cobas 19.2% and hc2 19.9% with high concordance (kappa=86.8% vs cobas, 81.55 vs hc2). Xpert, cobas and hc2 showed similar sensitivity (98.7%, 97.5%, 98.7%) for CIN2+. All pairwise comparisons had high concordance (Kappa ≥0.78 with any abnormal cytology. Xpert and hc2 were positive for all cases of ≥moderate dyskaryosis (N=63)), cobas was negative in two. Histology was available for 172 participants. 79 reported CIN2+, 47 CIN3+. All CIN3+ was positive on Xpert and hc2 and one case negative for cobas. One case of CIN2 was negative for all assays.

Conclusions

The performance of Xpert HPV Assay in a general screening population is comparable to established HPV tests. It offers simplicity of testing, flexibility with non-batching of individual samples and rapid turnaround time.

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This is the first study to report on the performance of the Xpert HPV Assay in a screening population.

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Xpert HPV Assay׳s performance in detecting HPV is comparable to two clinically validated HPV tests.

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Xpert HPV Assay showed a relative sensitivity of 98.73% for CIN 2 or higher and 100% for CIN3 or higher.