Human Papillomavirus DNA Methylation as a Biomarker for Cervical Precancer: Consistency across 12 Genotypes and Potential Impact on Management of HPV-Positive Women

Rearrangements of viral and human genomes at human papillomavirus integration events and their allele-specific impacts on cancer genome regulation

Human papillomavirus (HPV) integration has been implicated in transforming HPV infection into cancer. To resolve genome dysregulation associated with HPV integration, we performed Oxford Nanopore Technologies long-read sequencing on 72 cervical cancer genomes from a Ugandan data set that was previously characterized using short-read sequencing. We find recurrent structural rearrangement patterns at HPV integration events, which we categorize as del(etion)-like, dup(lication)-like, translocation, multi-breakpoint, or repeat region integrations. Integrations involving amplified HPV-human concatemers, particularly multi-breakpoint events, frequently harbor heterogeneous forms and copy numbers of the viral genome. Transcriptionally active integrants are characterized by unmethylated regions in both the viral and human genomes downstream from the viral transcription start site, resulting in HPV-human fusion transcripts. In contrast, integrants without evidence of expression lack consistent methylation patterns. Furthermore, whereas transcriptional dysregulation is limited to genes within 200 kb of an HPV integrant, dysregulation of the human epigenome in the form of allelic differentially methylated regions affects megabase expanses of the genome, irrespective of the integrant's transcriptional status. By elucidating the structural, epigenetic, and allele-specific impacts of HPV integration, we provide insight into the role of integrated HPV in cervical cancer.

Impact of knowledge of human papillomavirus positivity on cervical cytology performance in Latin America

BACKGROUND

Cervical cytology is recommended by the World Health Organization as a triage option in human papillomavirus (HPV)-based cervical cancer screening programs. We assessed the performance of cytology to detect CIN3+ without and with knowledge of HPV positivity.

METHODS

Women were screened with cytology and HPV across ESTAMPA study centers in Latin America. Screen-positives were referred to colposcopy with biopsy and treatment as needed. Cytology was initially interpreted without knowing HPV results. A subset of cytologies from HPV-positive women were reinterpreted at the same laboratories, with knowledge of HPV status, blinded to previous cytology and histological diagnosis. Performance indicators for cytology to detect CIN3+ without and with knowledge of HPV positivity were estimated.

FINDINGS

A total of 4087 women were included, of which 490 had histologically confirmed CIN3+ (455 CIN3 and 35 cancers). Cytology sensitivity without knowledge of HPV positivity for CIN3+ was 47.2% (95% CI = 42.5 to 51.9), whereas with knowledge of HPV positivity, the sensitivity was higher (58.9%, 95% CI = 54.2 to 63.5; P < .0001). The specificity without knowledge of HPV was 89.4% (95% CI = 88.2 to 90.5), whereas with knowledge of HPV positivity was 78.9% (95% CI = 77.4 to 80.4; P < .0001). Performance estimates varied by study center for cytology without knowing the HPV positivity (range = 32.8%-61.5% for sensitivity; range = 80.7%-98.6% for specificity). Similarly, performance varied with knowledge of HPV positivity (36.1%-93.4% for sensitivity; 39.6%-98.6% for specificity).

CONCLUSION

The increase in sensitivity of cytology with HPV knowledge was limited and highly variable, reinforcing the need for alternative triage methods to support cervical cancer elimination goals.

Advances in cervical cancer: current insights and future directions

In alignment with the World Health Organization's strategy to eliminate cervical cancer, substantial progress has been made in the treatment of this malignancy. Cervical cancer, largely driven by human papillomavirus (HPV) infection, is considered preventable and manageable because of its well-established etiology. Advancements in precision screening technologies, such as DNA methylation triage, HPV integration detection, liquid biopsies, and artificial intelligence-assisted diagnostics, have augmented traditional screening methods such as HPV nucleic acid testing and cytology. Therapeutic strategies aimed at eradicating HPV and reversing precancerous lesions have been refined as pivotal measures for disease prevention. The controversy surrounding surgery for early-stage cervical cancer revolves around identifying optimal candidates for minimally invasive and conservative procedures without compromising oncological outcomes. Recent clinical trials have yielded promising results for the development of systemic therapies for advanced cervical cancer. Immunotherapies, such as immune checkpoint inhibitors (ICIs), antibody-drug conjugates (ADCs), and targeted therapy have demonstrated significant effectiveness, marking a substantial advancement in cervical cancer management. Various combination therapies have been validated, and ongoing trials aim to enhance outcomes through the development of novel drugs and optimized combination regimens. The prospect of eradicating cervical cancer as the first malignancy to be eliminated is now within reach. In this review, we provide a comprehensive overview of the latest scientific insights, with a particular focus on precision managements for various stages of cervical disease, and explore future research directions in cervical cancer.

Anal cancer prevention: A field in need of scientific Advancement

Despite the availability of several human papillomavirus (HPV) vaccines, the incidence of HPV-associated anal cancer is growing at a rate of 2.2% each year. As shown in results from the recent Phase III ANCHOR study, the treatment of high-grade anal lesions in people living with HIV (PLWH) can significantly reduce rates of anal cancer development compared to active surveillance alone. As a result, screening programs to identify and treat patients with anal precancers are recommended by recent guidelines. Intense resources are needed to perform screening tests and follow-up abnormal results. The lack of effective and well-tolerated therapies, the lack of understanding regarding therapeutic targets, the paucity of preclinical models to test therapies, and the lack of biomarkers to determine which patients will develop cancer or respond to therapies are the issues that need to be addressed. We provide an overview of cutting-edge research and propose additional research that is needed to help move the field of anal cancer prevention forward. This review highlights the most significant current areas of research, as defined by the authors, and is by no means comprehensive of all anal dysplasia/cancer research.

Meeting report: Considerations for trial design and endpoints in licensing therapeutic HPV16/18 vaccines to prevent cervical cancer

Cervical cancer is a major cause of morbidity and mortality globally with a disproportionate impact on women in low- and middle-income countries. In 2021, the World Health Organization (WHO) called for increased vaccination, screening, and treatment to eliminate cervical cancer. However, even with widespread rollout of human papillomavirus (HPV) prophylactic vaccines, millions of women who previously acquired HPV infections will remain at risk for progression to cancer for decades to come. The development and licensing of an affordable, accessible therapeutic HPV vaccine, designed to clear or control carcinogenic HPV and/or to induce regression precancer could significantly contribute to the elimination efforts, particularly benefiting those who missed out on the prophylactic vaccine. One barrier to development of such vaccines is clarity around the regulatory pathway for licensure. In Washington, D.C. on September 12-13, 2023, a meeting was convened to provide input and guidance on trial design with associated ethical and regulatory considerations. This report summarizes the discussion and conclusions from the meeting. Expert presentation topics included the current state of research, potential regulatory challenges, WHO preferred product characteristics, modeling results of impact of vaccine implementation, epidemiology and natural history of HPV infection, immune responses related to viral clearance and/or precancer regression including potential biomarkers, and ethical considerations. Panel discussions were held to explore specific trial design recommendations to support the licensure process for two vaccine indications: (1) treatment of prevalent HPV infection or (2) treatment of cervical precancers. Discussion covered inclusion/exclusion criteria, study endpoints, sample size and power, safety, study length, and additional data needed, which are reported here. Further research of HPV natural history is needed to address identified gaps in regulatory guidance, especially for therapeutic vaccines intended to treat existing HPV infections.

The Future of Cervical Cancer Screening

Purpose

Cervical cancer remains a significant health concern, particularly in developing countries, where it is a leading cause of cancer-related deaths among women. Innovative technologies have emerged to improve the efficiency, cost-effectiveness, and sensitivity of cervical cancer screening and treatment methods. This study aims to explore the various approaches for the detection and treatment of human papillomavirus (HPV), cervical dysplasia (CD), and cervical cancer, highlighting new technologies and updated screening strategies in developing areas.

Patients and Methods

A comprehensive literature search was conducted using PubMed to identify relevant publications on the subject of cervical cancer screening and HPV detection.

Results

HPV infection and cervical cancer continue to pose significant global health challenges. Emerging technologies such as rapid, low-cost HPV testing combined with high-resolution digital colposcopy and artificial intelligence interpretation hold promise for efficient and sensitive screening. Advancements in HPV vaccine distribution, high-risk HPV screening, DNA methylation assays, dual-stain cytology, lab-on-chip assays, and deep learning technologies offer new avenues for improved detection and risk stratification.Research and innovations in detection and treatment methods are crucial for reducing the burden of these diseases worldwide.

Conclusion

Screening for HPV and CD plays a pivotal role in reducing the risk of cervical cancer-related mortality. The development of novel technologies, along with efforts to enhance global health equity and integrate cervical cancer prevention with HIV screening and treatment programs, represent critical steps toward achieving comprehensive cervical cancer screening on a global scale.

Epigenetic alteration in cervical cancer induced by human papillomavirus

The critical role of a subset of Human Papillomavirus in cervical cancer has been widely acknowledged and studied. Despite progress in our understanding of the viral molecular mechanisms of pathogenesis, knowledge of how infection with HPV oncogenic variants progresses from latent infection to incurable cancer has not been completely elucidated. In this paper we reviewed the relationship between HPV infection and epigenetic mechanisms such as histone acetylation and deacetylation, DNA methylation and non-coding RNAs associated with this infection and the carcinogenic process.

Methylation markers for anal cancer screening: A repeated cross-sectional analysis of people living with HIV, 2015-2016

People living with HIV (PLWH) are at highest risk of anal cancer and will benefit from optimized screening for early disease detection. We compared host DNA methylation markers in high-grade squamous intraepithelial lesions (HSIL) versus samples negative for intraepithelial lesions (NILM) or low-grade intraepithelial lesions (LSIL) in PLWH. We recruited PLWH identifying as male aged ≥18 years undergoing high-resolution anoscopy (HRA) in Seattle, Washington, 2015-2016. Anal brush samples were collected for HPV detection, genotyping, and pyrosequencing methylation (host genes ASCL1, PAX1, FMN2, and ATP10A); clinical data were abstracted from medical records. We assessed associations between methylation and presence and extent of HSIL using generalized estimating equation logistic regression, adjusting for age, CD4 count and HIV viral load. Marker panels using HPV DNA and methylation were also evaluated to predict prevalent HSIL. We analyzed 125 samples from 85 participants (mean age 50.1; standard deviation 11.0 years). ASCL1 (adjusted odds ratio [aOR] per 1 unit increase mean percent methylation: 1.07, 95% CI: 1.01-1.13) and FMN2 (aOR per 1 unit increase mean percent methylation: 1.14, 95% CI: 1.08-1.20) methylation were significantly associated with HSIL versus NILM/LSIL. ASCL1 (aOR: 1.06, 95% CI: 1.01-1.11) and FMN2 (aOR: 1.13, 95% CI: 1.08-1.17) methylation were positively associated with increasing HSIL extent. A panel combining methylation (ASCL1 and FMN2) and HPV DNA (HPV16, HPV18, and HPV31) demonstrated best balance of sensitivity (78.2%) and specificity (73.9%) for HSIL detection compared with methylation or HPV alone. Increasing levels of DNA methylation of ASCL1 and FMN2 were positively associated with HSIL detection in PLWH. Host gene methylation testing shows promise for HSIL screening and triage.

Biomarkers differentiating regression from progression among untreated cervical intraepithelial neoplasia grade 2 lesions

BACKGROUND

Cervical intraepithelial neoplasia grade 2 (CIN2) is one of the precursor stages before cervical lesions develop into cervical cancer. The spontaneous development of CIN2 is ambiguous. One part of CIN2 lesions will progress to cervical intraepithelial neoplasia grade 3 or worse (CIN3+), another part will regress to cervical intraepithelial neoplasia grade 1 or less (CIN1-), and the last part will persist. Although the guidelines suggest that CIN2 patients with fertility requirements can be treated conservatively to minimize the risk of infertility and obstetric complications, most CIN2 patients undergo surgical treatment to prevent the progression of the disease, which will lead to over-treatment and unnecessary complications.

AIM OF REVIEW

The clinical outcome of CIN2 lesions is unpredictable and depends on histopathological examinations. Thus, it is necessary to identify the biomarkers differentiating regression lesions from progression lesions, which is conducive to supporting individualised treatment. The natural history of CIN2 is commonly regulated by the interaction of human papillomavirus (HPV) viral factors (HPV genotype and HPV methylation), host factors (p16/Ki-67 status, host gene methylation effects, human leukocyte antigen subtypes and immune microenvironment) and other factors (vaginal microbiota).

KEY SCIENTIFIC CONCEPTS OF REVIEW

This review summarized the biomarkers predicting the spontaneous regression of CIN2, which correlated with HPV infection, the (epi)genetic change of host genes and microenvironment change. However, potential biomarkers must be validated with prospective cohort studies, which should be conducted with expanded enrollment, a longer observational period and the tracking of more patients.

Emerging trends and hotspots in cervical intraepithelial neoplasia research from 2013 to 2023: A bibliometric analysis

Background

Cervical intraepithelial neoplasia (CIN) encompasses a range of cervical lesions that are closely linked to cervical invasive carcinoma. Early detection and timely treatment of CIN are crucial for preventing the progression of the disease. However, no bibliometric analysis has been conducted in this area. This research aimed to employ bibliometric analysis to summarize the current research hotspots and estimate future research trends in the CIN field.

Methods

Publications related to CIN (2013-2023) were retrieved from the Science-Citation-Index-Expanded-of-Web-of-Science-Core-Collection. CiteSpace, VOSviewer, and the bibliometric-Online-Analysis-Platform-of-Literature-Metrology were employed to analyze the yearly research output, collaborating institutions or countries, leading researchers, principal journals, co-referenced sources, and emerging keywords.

Results

In total, 4677 articles on CIN that were published from 2013 to 2023 and met our criteria were extracted. Major publishing platforms were predominantly USA until 2017 when China emerged as the leading source of publications about CIN. The USA was the leading nation in international collaborations. The National-Cancer-Institute (NCI) was the institution with the most publications. Schiffman Mark produced the highest number of articles, with a total of 92. Ten major clusters were identified through co-cited keyword clustering, including prevalence, human papillomavirus, DNA methylation, p16, methylation, conization, HPV genotyping tests (VALGENT), deep learning, vaginal microbiome, and immunohistochemistry. Keyword burst analysis showed that photodynamic therapy and deep learning emerged as prominent research focal points with significant impact in resent three years.

Conclusion

Global publications on CIN research showed a relatively stable trend over the past eleven years. Current research hotspots are deep learning and photodynamic therapy. This research offered organized data and insightful guidance for future studies, which may help better prevent, screen, and treat CIN.

DNA methylation as a triage tool for cervical cancer screening - A meeting report

Introduction

DNA methylation is proposed as a novel biomarker able to monitor molecular events in human papillomavirus (HPV) infection pathophysiology, enabling the distinction between HPV-induced lesions with regression potential from those that may progress to HPV-related cancer.

Methods

This meeting report summarises the presentations and expert discussions during the HPV Prevention and Control Board-focused topic technical meeting on DNA methylation validation in clinician-collected and self-collected samples, novel DNA methylation markers discovery, implementation in cervical cancer screening programs, and their potential in women living with human immunodeficiency virus (HIV).

Results

Data presented in the meeting showed that HPV-positive, baseline methylation-negative women have a lower cumulative cervical cancer incidence than baseline cytology-negative women, making DNA methylation an attractive triage strategy. However, additional standardised data in different settings (low- versus high-income settings), samples (clinician-collected and self-collected), study designs (prospective, modelling, impact) and populations (immunocompetent women, women living with HIV) are needed.

Conclusion

Establishing international validation guidelines were identified as the way forward towards accurate validation and subsequent implementation in current screening programs.

Human papillomavirus (HPV) DNA methylation changes in HPV-associated head and neck cancer

Despite the rising incidence, currently, there are no early detection methods for HPV-driven HNC (HPV-HNC). Cervical cancer studies suggest that HPV DNA methylation changes can be used as a biomarker to discriminate cancer patients from HPV-infected individuals. As such, this study was designed to establish a protocol to evaluate DNA methylation changes in HPV late genes and long control region (LCR) in saliva samples of HPV-HNC patients and HPV-positive controls. Higher methylation levels were detected in HPV late genes (L1 and L2) in both tumour and saliva samples of HPV-HNC patients compared with HPV-positive controls. Moreover, methylation patterns between tumours and corresponding saliva samples were observed to have a strong correlation (Passing-Bablok regression analysis; τ = 0.7483, P < 0.0001). Considering the differences between HNC and controls in methylation levels in late genes, and considering primer amplification efficiencies, 13 CpG sites located at L1 and L2 genes were selected for further evaluation. A total of 18 HNC saliva samples and 10 control saliva samples were assessed for the methylation levels in the selected sites. From the CpG sites evaluated statistically significant differences were identified for CpG sites at L2-CpG 6 (P = 0.0004), L1-CpG 3 (P = 0.0144), L1-CpG 2 (P = 0.0395) and L2-CpG 19 (P = 0.0455). Our pilot data indicate that higher levels of DNA methylation in HPV late genes are indicative of HPV-HNC risk, and it is a potential supplementary biomarker for salivary HPV detection-based HPV-HNC screening.

A novel human papillomavirus and host DNA methylation score and detection of cervical adenocarcinoma

BACKGROUND

The widespread introduction of Pap testing in the 1960s was followed by substantial reductions in the incidence of cervical squamous cell cancer (SCC). However, the incidence of cervical adenocarcinoma (ADC) did not decrease, likely because of low Pap test sensitivity for ADC and adenocarcinoma in situ (AIS). This study assessed a novel human papillomavirus (HPV) and host DNA Methylation Score for AIS and ADC screening.

METHODS

We measured methylation levels at CpG sites in the L2/L1 open reading frames of HPV16, HPV18, and HPV45-as well as 2 human loci, DCC and HS3ST2. Specifically, we tested exfoliated cervicovaginal cells from women in the HPV Persistence and Progression (PaP) cohort who were positive for 1 of HPV16, 18, or 45, including: 1) 176 with AIS/ADC, 2) 353 with cervical intraepithelial neoplasia-3 (CIN3) or SCC, and 3) controls who either cleared (HPV-Clearers; n = 579) or had persistent HPV16, 18, or 45 infection (HPV-Persisters; n = 292). CpG site-specific methylation percentages were measured using our reported next-generation methods. The Methylation Score was the average methylation percentage across all 35 CpG sites tested.

RESULTS

Each individual CpG site had higher methylation percentages in exfoliated cervicovaginal cells collected from patients with AIS/ADC, and as well as those with CIN3/SCC, relative to either control group (weakest P  = .004). The Methylation Score for AIS/ADC had a sensitivity of 74% and specificity of 89%. The multivariate odds ratio (OR) between the Methylation Score (4th vs 1st quartile) for AIS/ADC was ORq4-q1 = 49.01 (PBenjamini-Hochberg = 4.64E-12), using HPV-Clearers as controls. CIN3/SCC had similar, albeit weaker, associations with the Methylation Score.

CONCLUSIONS

HPV16/18/45-infected women with Methylation Scores in the highest quartile had very high odds of AIS/ADC, suggesting they may warrant careful histologic evaluation of the cervical transition zone (eg, conization or loop electrosurgical excision procedure [LEEP]).

A paradigm for post-embryonic Oct4 re-expression: E7-induced hydroxymethylation regulates Oct4 expression in cervical cancer

The Octamer-binding transcription factor-4 (Oct4) is upregulated in different malignancies, yet a paradigm for mechanisms of Oct4 post-embryonic re-expression is inadequately understood. In cervical cancer, Oct4 expression is higher in human papillomavirus (HPV)-related than HPV-unrelated cervical cancers and this upregulation correlates with the expression of the E7 oncogene. We have reported that E7 affects the Oct4-transcriptional output and Oct4-related phenotypes in cervical cancer, however, the underlying mechanism remains elusive. Here, we characterize the Oct4-protein interactions in cervical cancer cells via computational analyses and Mass Spectrometry and reveal that Methyl-binding proteins (MBD2 and MBD3), are determinants of Oct4-driven transcription. E7 triggers MBD2 downregulation and TET1 upregulation, thereby disrupting the methylation status of the Oct4 gene. This coincides with an increase in the total DNA hydroxymethylation leading to the re-expression of Oct4 in cervical cancer and likely affecting broader transcriptional patterns. Our findings reveal a previously unreported mechanism by which the E7 oncogene can regulate Oct4 re-expression and global transcriptional patterns by increasing DNA hydroxymethylation and lowering the barrier to cellular plasticity during carcinogenesis.

EBV infection of primary colonic epithelial cells causes inflammation, DDR and autophagy dysregulation, effects that may predispose to IBD and carcinogenesis

EBV is a gammaherpesvirus strongly associated to human cancer. The virus has been shown to play a role also in inflammatory diseases, including IBD, in the context of which colon cancer more frequently arise. In this study, we show for the first time that EBV infects primary colonic epithelial cells (HCoEpC), promotes pro-inflammatory cytokine secretion and activates molecular pathways bridging inflammation and cancer, such as ERK1/2. These effects, occurring in the course of the lytic phase of the viral life cycle, led to DDR and autophagy dysregulation. Such cellular responses, playing a key role in the maintenance of proteostasis and genome integrity, are essential to prevent carcinogenesis. Interestingly, we found that the use of the demethylating agent 5-AZA could counteract most of the effects induced by EBV infection in HCoEpC, suggesting that DNA hyper-methylation may strongly contribute to viral-driven inflammation and colon cancer predisposition.

DNA Methylation-Based Testing in Peripheral Blood Mononuclear Cells Enables Accurate and Early Detection of Colorectal Cancer

An effective blood-based method for the diagnosis of colorectal cancer has not yet been developed. Molecular alterations of immune cells occur early in tumorigenesis, providing the theoretical underpinning for early cancer diagnosis based on immune cell profiling. Therefore, we aimed to develop an effective detection method based on peripheral blood mononuclear cells (PBMC) to improve the diagnosis of colorectal cancer. Analysis of the genome-wide methylation landscape of PBMCs from patients with colorectal cancer and healthy controls by microarray, pyrosequencing, and targeted bisulfite sequencing revealed five DNA methylation markers for colorectal cancer diagnosis, especially early-stage colorectal cancer. A single-tube multiple methylation-specific quantitative PCR assay (multi-msqPCR) for simultaneous detection of five methylation markers was established, which allowed quantitative analysis of samples with as little as 0.1% PBMC DNA and had better discriminative performance than single-molecule detection. Then, a colorectal cancer diagnostic model (CDM) based on methylation markers and the multi-msqPCR method was constructed that achieved high accuracy for early-stage colorectal cancer (AUC = 0.91; sensitivity = 81.18%; specificity = 89.39%), which was improved compared with CEA (AUC = 0.79). The CDM also enabled a high degree of discrimination for advanced adenoma cases (AUC = 0.85; sensitivity = 63.04%). Follow-up data also demonstrated that the CDM could identify colorectal cancer potential up to 2 years before currently used diagnostic methods. In conclusion, the approach constructed in this study based on PBMC-derived DNA methylation markers and a multi-msqPCR method is a promising and easily implementable diagnostic method for early-stage colorectal cancer.

SIGNIFICANCE

Development of a diagnostic model for early colorectal cancer based on epigenetic analysis of PBMCs supports the utility of altered DNA methylation in immune cells for cancer diagnosis.

Primary Human Papillomavirus Testing and Other New Technologies for Cervical Cancer Screening

Cervical cancer screening has saved the lives of millions in regions where routine gynecologic care is readily accessible. As screening continues to evolve away from cervical cytology to primary human papillomavirus (HPV) testing, robust prospective cohort data have allowed for precise risk stratification and improved our ability to identify those at greatest risk of high-grade dysplasia and decrease unnecessary diagnostic procedures. New technologies such as p16/Ki-67 dual stain testing and HPV methylation panels, which offer comparable performance to co-testing and can be developed into high-throughput workflows, could lead to a fully molecular Pap test. Self-sampling in the United States, where the initial screen can be done in the home, in conjunction with new screening technologies, may decrease the existing hurdles of routine cervical cancer screening. Implementation barriers include issues with workflow, workforce, and cost. These need to be addressed to achieve an improved and more equitable cervical cancer screening program in the United States.

The Role of p16/Ki67 Dual Staining in Cervical Cancer Screening

Cervical cancer screening has enabled a decrease in the incidence and mortality of cervical cancer. Various screening modalities have been studied to date. In many countries, screening is still based on cervical cytology, where cervical cells obtained either on glass or in a liquid medium are examined under a microscope. However, the fact that the vast majority of cervical cancers are a result of persistent infection with high-risk human papillomaviruses (hr-HPV) has led to the implementation of primary HPV screening in many countries. Taking into consideration the fact that the majority of HPV infections are transient and do not cause cervical precancer, effective triage methods are needed to prevent an increase in colposcopy referrals. Among these, the most extensively investigated are HPV genotyping, HPV methylation, and p16/Ki67 dual staining. In this manuscript, we briefly summarize the current knowledge regarding different screening strategies for the prevention of cervical cancer, with a focus on p16/Ki67 dual staining. In addition, we provide an explanation regarding the rationale for the use of various screening modalities based on the molecular biology of cervical cancer and cervical precancerous lesions.

Methylation haplotypes of the insulin gene promoter in children and adolescents with type 1 diabetes: Can a dimensionality reduction approach predict the disease?

DNA methylation of cytosine-guanine sites (CpGs) is associated with type 1 diabetes (T1D). The sequence of methylated and non-methylated sites in a specific genetic region constitutes its methyl-haplotype. The aim of the present study was to identify insulin gene promoter (IGP) methyl-haplotypes among children and adolescents with T1D and suggest a predictive model for the discrimination of cases and controls according to methyl-haplotypes. A total of 40 individuals (20 T1D) participated. The IGP region from peripheral whole blood DNA of 40 participants (20 T1D) was sequenced using next-generation sequencing, sequences were read using FASTQ files and methylation status was calculated by python-based pipeline for targeted deep bisulfite sequenced amplicons (ampliMethProfiler). Methylation profile at 10 CpG sites proximal to transcription start site of the IGP was recorded and coded as 0 for unmethylation or 1 for methylation. A single read could result in '1111111111' methyl-haplotype (all methylated), '000000000' methyl-haplotype (all unmethylated) or any other combination. Principal component analysis was applied to the generated methyl-haplotypes for dimensionality reduction, and the first three principal components were employed as features with five different classifiers (random forest, decision tree, logistic regression, Naive Bayes, support vector machine). Naive Bayes was the best-performing classifier, with 0.9 accuracy. Predictive models were evaluated using receiver operating characteristics (AUC 0.96). Methyl-haplotypes '1111111111', '1111111011', '1110111111', '1111101111' and '1110101111' were revealed to be the most significantly associated with T1D according to the dimensionality reduction method. Methylation-based biomarkers such as IGP methyl-haplotypes could serve to identify individuals at high risk for T1D.

Molecular triaging options for women testing HPV positive with self-collected samples

We review developments in molecular triaging options for women who test positive for high-risk human papillomavirus (hrHPV) on self-collected samples in the context of cervical cancer elimination. The World Health Organization (WHO) recommends hrHPV screening as the primary test for cervical screening due to its high sensitivity compared to other screening tests. However, when hrHPV testing is used alone for treatment decisions, a proportion of women of childbearing age receive unnecessary treatments. This provides the incentive to optimize screening regimes to minimize the risk of overtreatment in women of reproductive age. Molecular biomarkers can potentially enhance the accuracy and efficiency of screening and triage. HrHPV testing is currently the only screening test that allows triage with molecular methods using the same sample. Additionally, offering self-collected hrHPV tests to women has been reported to increase screening coverage. This creates an opportunity to focus health resources on linking screen-positive women to diagnosis and treatment. Adding an additional test to the screening algorithm (a triage test) may improve the test's positive predictive value (PPV) and offer a better balance of benefits and risks for women. Conventional triage methods like cytology and visual inspection with acetic acid (VIA) cannot be performed on self-collected samples and require additional clinic visits and subjective interpretations. Molecular triaging using methods like partial and extended genotyping, methylation tests, detection of E6/E7 proteins, and hrHPV viral load in the same sample as the hrHPV test may improve the prediction of cervical intraepithelial neoplasia grade 2 or worse (CIN2+) and invasive cancer, offering more precise, efficient, and cost-effective screening regimes. More research is needed to determine if self-collected samples are effective and cost-efficient for diverse populations and in comparison to other triage methods. The implementation of molecular triaging could improve screening accuracy and reduce the need for multiple clinical visits. These important factors play a crucial role in achieving the global goal of eliminating cervical cancer as a public health problem.

Circulating Cell-Free SEPT9 DNA Methylation in Blood Is a Biomarker for Minimal Residual Disease Detection in Head and Neck Squamous Cell Carcinoma Patients

BACKGROUND

Tumorous SEPT9 (septin 9, SEPTIN9) circulating cell-free DNA (ccfDNA) methylation in blood plasma is a powerful biomarker for diagnosis, molecular staging, prognosis, and recurrence monitoring in head and neck squamous cell carcinoma (HNSCC) patients. The present study aimed to evaluate the clinical performance of SEPT9 ccfDNA methylation to detect post-surgical minimal residual disease (MRD) in patients with localized or locally advanced HNSCC treated with curative intent.

METHODS

We applied quasi-digital methylation-specific real-time PCR to quantify SEPT9 ccfDNA methylation levels 2 to 30 days post-surgically in plasma from n = 219 prospectively enrolled HNSCC patients. We tested the associations of SEPT9 ccfDNA methylation with clinicopathological parameters and used Kaplan-Meier and Cox proportional hazards analyses for univariate, pairwise bivariate, and multivariate analyses of disease-free survival.

RESULTS

Of 219 patients, 26.5% (58/219) were post-surgically SEPT9 ccfDNA methylation positive. SEPT9 ccfDNA methylation positivity was significantly associated with tumor site, American Joint Committee on Cancer/Union for International Cancer Control (AJCC/UICC; 8th edition) tumor stage, nodal category and extracapsular extension, lymphatic and vascular invasion, and surgical margin. Bivariate Cox proportional hazards analysis proved post-surgical SEPT9 ccfDNA methylation positivity to be an independent prognostic factor tested together with AJCC/UICC tumor stage (SEPT9: hazard ratio [HR] = 2.43, 95% CI, 1.37-4.30, P = 0.002; AJCC/UICC stage: HR = 1.48, 95% CI, 1.11-1.98, P = 0.008).

CONCLUSIONS

Post-surgical SEPT9 ccfDNA methylation may aid to identify high-risk HNSCC patients who could benefit from an intensified adjuvant treatment and surveillance.

HPV Testing and its Role in Cervical Cancer Screening

The recognition that persistent infection with carcinogenic human papillomavirus (HPV) is a necessary cause of cervical precancer and cancer has led to the introduction of HPV testing into cervical cancer screening, either as a primary screening test or in conjunction with cervical cytology (i.e., co-testing). HPV testing has much higher sensitivity for detection of cervical precancer and provides greater long-term reassurance if negative compared to cytology. However, most HPV infections are transient, and do not progress to invasive cancer, thus triage tests are required to identify individuals who should be referred to colposcopy for diagnostic evaluation. This chapter begins with a description of the biology, natural history, and epidemiology of HPV as a foundation for understanding the role of HPV in cervical carcinogenesis. This section is followed by a detailed discussion regarding the introduction of HPV-based testing and triage into cervical cancer screening and management. Summarized triage tests include cervical cytology, HPV genotyping, p16/Ki-67 dual stain, and HPV and cellular methylation markers. The final section of this chapter includes an important discussion on cervical cancer disparities, particularly within the United States, followed by concluding remarks.

Cervical Cancer Screening: A Review

Importance

Each year in the US, approximately 100 000 people are treated for cervical precancer, 14 000 people are diagnosed with cervical cancer, and 4000 die of cervical cancer.

Observations

Essentially all cervical cancers worldwide are caused by persistent infections with one of 13 carcinogenic human papillomavirus (HPV) genotypes: 16, 18, 31, 33, 35, 39, 45, 51, 52, 56, 58, 59, and 68. HPV vaccination at ages 9 through 12 years will likely prevent more than 90% of cervical precancers and cancers. In people with a cervix aged 21 through 65 years, cervical cancer is prevented by screening for and treating cervical precancer, defined as high-grade squamous intraepithelial lesions of the cervix. High-grade lesions can progress to cervical cancer if not treated. Cervicovaginal HPV testing is 90% sensitive for detecting precancer. In the general population, the risk of precancer is less than 0.15% over 5 years following a negative HPV test result. Among people with a positive HPV test result, a combination of HPV genotyping and cervical cytology (Papanicolaou testing) can identify the risk of precancer. For people with current precancer risks of less than 4%, repeat HPV testing is recommended in 1, 3, or 5 years depending on 5-year precancer risk. For people with current precancer risks of 4% through 24%, such as those with low-grade cytology test results (atypical squamous cells of undetermined significance [ASC-US] or low-grade squamous intraepithelial lesion [LSIL]) and a positive HPV test of unknown duration, colposcopy is recommended. For patients with precancer risks of less than 25% (eg, cervical intraepithelial neoplasia grade 1 [CIN1] or histologic LSIL), treatment-related adverse effects, including possible association with preterm labor, can be reduced by repeating colposcopy to monitor for precancer and avoiding excisional treatment. For patients with current precancer risks of 25% through 59% (eg, high-grade cytology results of ASC cannot exclude high-grade lesion [ASC-H] or high-grade squamous intraepithelial lesion [HSIL] with positive HPV test results), management consists of colposcopy with biopsy or excisional treatment. For those with current precancer risks of 60% or more, such as patients with HPV-16-positive HSIL, proceeding directly to excisional treatment is preferred, but performing a colposcopy first to confirm the need for excisional treatment is acceptable. Clinical decision support tools can facilitate correct management.

Conclusions and Relevance

Approximately 100 000 people are treated for cervical precancer each year in the US to prevent cervical cancer. People with a cervix should be screened with HPV testing, and if HPV-positive, genotyping and cytology testing should be performed to assess the risk of cervical precancer and determine the need for colposcopy or treatment. HPV vaccination in adolescence will likely prevent more than 90% of cervical precancers and cancers.

The Role of Methylation of Host and/or Human Papillomavirus (HPV) DNA in Management of Cervical Intraepithelial Neoplasia Grade 2 (CIN2) Lesions

Cervical intraepithelial neoplasia grade 2 (CIN2) is an intermediate stage between CIN 1, which is a low-grade lesion, and CIN3, which is the immediate precursor of cervical cancer (CC). Traditionally, CIN2 was regarded as a high-grade lesion and was treated with conization or ablative methods. In recent years, there has been a shift in the management of younger patients, who are now more often being managed conservatively due to frequent spontaneous CIN2 regression and possible adverse effects of treatment on future pregnancies. Because the risk of progression to CC still exists with conservative management, a personalized approach is needed to identify patients with a higher probability of progression. In this regard, research has focused on the role of host and human papillomavirus (HPV) gene methylation. This systematic review summarizes the current knowledge regarding conservative CIN2 management focusing on the main methylation markers and its implementation in conservative CIN2 management, and it describes major ongoing longitudinal studies on the subject. The review showed that DNA methylation is an accurate predictor of disease progression and a valid triage tool for HPV-positive women, with CIN2 performing better than triage cytology. Because virtually all CCs are methylation-positive, methylation-negative women at baseline have an extremely low risk of CC.

Meta-analysis of downregulated E-cadherin as a diagnostic biomarker for cervical cancer

OBJECTIVE

Downregulation of E-cadherin function or expression has been implicated in the progression of cervical cancer. This meta-analysis of updated publications was performed to assess the association of expression alteration of E-cadherin with disease severity and then to determine the diagnostic accuracy of E-cadherin in discriminating cervical lesions including cervical intraepithelial neoplasia (CIN) grade 1 (CIN1), CIN grade 2 (CIN2), CIN grade 3 (CIN3), and cervical cancer.

METHODS

The articles published from inception to January 2021 were searched in PubMed, EBSCO, CNKI, and WanFang Database and then evaluated according to the criteria of meta-analysis. The eligible studies were retrieved and further analyzed. A bivariate mixed effects binary regression model was applied to determine pooled effect estimates.

RESULTS

16 studies with 2436 subjects from 7 countries were eligible for this meta-analysis. When compared with CIN1 control, the pooled odds ratios (ORs) with 95% confidence interval (CI) for the association of E-cadherin positivity with CIN2, CIN3, and cervical cancer were 0.34 (95% CI 0.23-0.51), 0.23 (95% CI 0.10-0.54), and 0.10 (95% CI 0.07-0.14), respectively. The pooled sensitivity and specificity for CIN3 or worse were 0.60 (95% CI 0.48-0.70) and 0.82 (95% CI 0.73-0.88) respectively, with the AUC of 0.78 (95% CI 0.74-0.82). Similar performance was found in CIN2 or worse.

CONCLUSION

These findings demonstrated that the loss of E-cadherin protein was associated with worsened cervical lesions. E-cadherin might serve as a promising diagnostic biomarker to facilitate the discrimination of precancerous and cancerous lesions.

DNA methylation testing with S5 for triage of high-risk HPV positive women

Methylation of host and viral genes is promising for triage of women with high-risk human papillomavirus infections (hrHPV). Using a population-based sample of hrHPV positive women with cervical biopsies within 12 months after cervical screening, the clinical value of the S5 methylation classifier (S5), HPV genotyping and cytology were compared as potential triage tests, for outcomes of cervical intraepithelial neoplasia (CIN) grade 3 or greater (CIN3+), CIN2+ and CIN2, and the area under the curve (AUC) calculated. S5 scores increased with histopathology severity (Ptrend  < .001). For CIN3+, the AUC was 0.780 suggesting S5 provides good discrimination between Collapse

Key Words

• DNA methylation
• cervical cancer
• high-risk HPV
• molecular markers
• triage

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MESH Headings

• DNA Methylation
• Early Detection of Cancer
• Female
• Human papillomavirus 16/genetics
• Human papillomavirus 18/genetics
• Humans
• Papillomaviridae/genetics
• Papillomavirus Infections/complications
• Papillomavirus Infections/diagnosis
• Papillomavirus Infections/genetics
• Triage
• Uterine Cervical Neoplasms/diagnosis
• Uterine Cervical Neoplasms/genetics
• Uterine Cervical Neoplasms/pathology
• Uterine Cervical Dysplasia/diagnosis
• Uterine Cervical Dysplasia/genetics
• Uterine Cervical Dysplasia/pathology

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Grants

• 21070 Cancer Research UK
• 27046 Cancer Research UK
• U19 AI113187 NIAID NIH HHS
• C27045/A27046 Cancer Research UK
• Cancer Research UK
• National Institute of Allergy and Infectious Diseases

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Affiliation(s)

Rachael Adcock Centre for Cancer Prevention, Wolfson Institute of Population HealthQueen Mary University of LondonLondonUK Center for HPV PreventionUniversity of New Mexico Comprehensive Cancer CenterAlbuquerqueNew MexicoUSA
Belinda Nedjai Centre for Cancer Prevention, Wolfson Institute of Population HealthQueen Mary University of LondonLondonUK
Attila T. Lorincz Centre for Cancer Prevention, Wolfson Institute of Population HealthQueen Mary University of LondonLondonUK
Dorota Scibior‐Bentkowska Centre for Cancer Prevention, Wolfson Institute of Population HealthQueen Mary University of LondonLondonUK
Rawinder Banwait Centre for Cancer Prevention, Wolfson Institute of Population HealthQueen Mary University of LondonLondonUK
Norah Torrez‐Martinez Center for HPV PreventionUniversity of New Mexico Comprehensive Cancer CenterAlbuquerqueNew MexicoUSA
Michael Robertson Center for HPV PreventionUniversity of New Mexico Comprehensive Cancer CenterAlbuquerqueNew MexicoUSA
Jack Cuzick Centre for Cancer Prevention, Wolfson Institute of Population HealthQueen Mary University of LondonLondonUK
Cosette M. Wheeler Center for HPV PreventionUniversity of New Mexico Comprehensive Cancer CenterAlbuquerqueNew MexicoUSA
New Mexico HPV Pap Registry Steering Committee

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A systematic review and meta-analysis of the diagnostic effectiveness of human papillomavirus methylation biomarkers for detection of cervical cancer

Background: The aim of this systematic review and meta-analysis was to assess the evidence for the diagnostic effectiveness of human papillomavirus (HPV) methylation biomarkers for detection of cervical cancer. Methods: PubMed, Embase and Web of Science were searched. Nine articles focusing on HPV methylation for detection of precancerous and cancerous cervical lesions were included. The QUADAS-2 tool was used for quality assessment. The receiver operating characteristic (ROC) was the main diagnostic performance parameter extracted. Results: Of the nine articles included in this study, seven were of moderate quality and two were of high quality. A meta-analysis of the ROC for 27 HPV methylation biomarkers revealed an overall pooled ROC of 0.770 (95% CI: 0.720-0.819; I²: 98.4%; Q: 1537.4; p < 0.01). Four methylation biomarkers had strong diagnostic ability (ROC > 0.900), 17 were moderate (ROC: 0.7000-0.8999) and six were poor (ROC < 0.700). Conclusion: HPV methylation biomarkers hold significant promise as independent screening tests for the detection of cervical precancerous and cancerous lesions.

Full genotyping and FAM19A4/miR124-2 methylation analysis in high-risk human papillomavirus-positive samples from women over 30 years participating in cervical cancer screening in Örebro, Sweden

Currently, cervical cancer prevention is undergoing comprehensive development regarding human papillomavirus (HPV) vaccination and cervical cancer screening. In Sweden and many other countries, high coverage vaccinated cohorts are entering screening within the next few years. This entails demands for baseline HPV genotype data across the screening age range for surveillance and a basis for screening program adjustment. In 2016, Örebro County, Sweden, changed to primary HPV screening using HPV mRNA testing followed by cytology triage. An alternative triage method to cytology could allow for a fully molecular screening algorithm and be implemented in a screening program where self-sampling is included. Hypermethylation analysis of the human genes FAM19A4/miR124-2 has been suggested as a promising triage method. HPV mRNA-positive screening samples (n = 529) were included and subjected to genotyping targeting a broad range of both low-risk and high-risk genotypes in addition to hypermethylation analysis of the two human genes FAM19A4/miR124-2. Data were connected to cytological and histological status and age. The most commonly detected genotypes were HPV31, 16, and 52. In addition, HPV18 was one of the most common genotypes in high-grade squamous intraepithelial lesions (HSILs) samples. In relation to available vaccines, 26% of the women with histological HSIL or cancer (≥HSIL) tested positive for only hrHPV included in the quadrivalent vaccine and 77% of the genotypes in the nonavalent vaccine. According to these figures, a relatively large proportion of the HSILs will probably remain, even after age cohorts vaccinated with the quadrivalent vaccine enter the screening program. Hypermethylation positivity was associated with increasing age, but no HPV-related independently predictive factors were found. Accordingly, age needs to be considered in development of future screening algorithms including triage with hypermethylation methodology.

False Negative Results in Cervical Cancer Screening-Risks, Reasons and Implications for Clinical Practice and Public Health

False negative (FN) results in cervical cancer (CC) screening pose serious risks to women. We present a comprehensive literature review on the risks and reasons of obtaining the FN results of primary CC screening tests and triage methods and discuss their clinical and public health impact and implications. Misinterpretation or true lack of abnormalities on a slide are the reasons of FN results in cytology and p16/Ki-67 dual-staining. For high-risk human papillomavirus (HPV) molecular tests, those include: truly non-HPV-associated tumors, lesions driven by low-risk HPV types, and clearance of HPV genetic material before sampling. Imprecise disease threshold definition lead to FN results in visual inspection with acetic acid. Lesions with a discrete colposcopic appearance are a source of FN in colposcopic procedures. For FAM19A4 and hsa-miR124-2 genes methylation, those may originate from borderline methylation levels. Histological misinterpretation, sampling, and laboratory errors also play a role in all types of CC screening, as well as reproducibility issue, especially in methods based on human-eye evaluation. Primary HPV-based screening combined with high quality-assured immunocytochemical and molecular triage methods seem to be an optimal approach. Colposcopy with histological evaluation remains the gold standard for diagnosis but requires quality protocols and assurance measures.

Epigenetic and Transcriptomic Regulation Landscape in HPV+ Cancers: Biological and Clinical Implications

Human Papillomavirus (HPV) is an oncogenic virus that causes the highest number of viral-associated cancer cases and deaths worldwide, with more than 690,000 new cases per year and 342,000 deaths only for cervical cancer (CC). Although the incidence and mortality rates for CC are declining in countries where screening and vaccination programs have been implemented, other types of cancer in which HPV is involved, such as oropharyngeal cancer, are increasing, particularly in men. Mutational and transcriptional profiles of various HPV-associated neoplasms have been described, and accumulated evidence has shown the oncogenic capacity of E6, E7, and E5 genes of high-risk HPV. Interestingly, transcriptomic analysis has revealed that although a vast majority of the human genome is transcribed into RNAs, only 2% of transcripts are translated into proteins. The remaining transcripts lacking protein-coding potential are called non-coding RNAs. In addition to the transfer and ribosomal RNAs, there are regulatory non-coding RNAs classified according to size and structure in long non-coding RNAs (lncRNAs), circular RNAs (circRNAs), and small RNAs; such as microRNAs (miRNAs), piwi-associated RNAs (piRNAs), small nucleolar RNAs (snoRNAs) and endogenous short-interfering RNAs. Recent evidence has shown that lncRNAs, miRNAs, and circRNAs are aberrantly expressed under pathological conditions such as cancer. In addition, those transcripts are dysregulated in HPV-related neoplasms, and their expression correlates with tumor progression, metastasis, poor prognosis, and recurrence. Nuclear lncRNAs are epigenetic regulators involved in controlling gene expression at the transcriptional level through chromatin modification and remodeling. Moreover, disruption of the expression profiles of those lncRNAs affects multiple biological processes such as cell proliferation, apoptosis, and migration. This review highlights the epigenetic alterations induced by HPV, from infection to neoplastic transformation. We condense the epigenetic role of non-coding RNA alterations and their potential as biomarkers in transformation's early stages and clinical applications. We also summarize the molecular mechanisms of action of nuclear lncRNAs to understand better their role in the epigenetic control of gene expression and how they can drive the malignant phenotype of HPV-related neoplasia. Finally, we review several chemical and epigenetic therapy options to prevent and treat HPV-associated neoplasms.

HPV16 and HPV18 Genome Structure, Expression, and Post-Transcriptional Regulation

Human papillomaviruses (HPV) are a group of small non-enveloped DNA viruses whose infection causes benign tumors or cancers. HPV16 and HPV18, the two most common high-risk HPVs, are responsible for ~70% of all HPV-related cervical cancers and head and neck cancers. The expression of the HPV genome is highly dependent on cell differentiation and is strictly regulated at the transcriptional and post-transcriptional levels. Both HPV early and late transcripts differentially expressed in the infected cells are intron-containing bicistronic or polycistronic RNAs bearing more than one open reading frame (ORF), because of usage of alternative viral promoters and two alternative viral RNA polyadenylation signals. Papillomaviruses proficiently engage alternative RNA splicing to express individual ORFs from the bicistronic or polycistronic RNA transcripts. In this review, we discuss the genome structures and the updated transcription maps of HPV16 and HPV18, and the latest research advances in understanding RNA cis-elements, intron branch point sequences, and RNA-binding proteins in the regulation of viral RNA processing. Moreover, we briefly discuss the epigenetic modifications, including DNA methylation and possible APOBEC-mediated genome editing in HPV infections and carcinogenesis.

Detection of Circulating HPV16 DNA as a Biomarker for Cervical Cancer by a Bead-Based HPV Genotyping Assay

Human papillomavirus (HPV) circulating tumor DNA (HPV ctDNA) was proposed as a biomarker for the detection and disease monitoring of HPV-related cancers. One hundred eighty plasma samples obtained from women diagnosed with HPV16-positive cervical cancer (CC) (n = 100), HPV16-positive premalignant lesions (cervical intraepithelial neoplasia grade 3 [CIN3]) (n = 20), and HPV DNA-negative controls (n = 60) were randomly selected from the archives for evaluating the performance of a bead-based HPV genotyping assay (E7 type-specific multiplex genotyping assay [E7-MPG]) in detecting HPV16 ctDNA. The performance of the E7-MPG was compared with those of DNA detection by droplet digital PCR (ddPCR) and detection of HPV16 E6 antibodies evaluated in an independent study. Internal controls to assess DNA quality were included in the molecular assays, i.e., beta-globin and ESR1, respectively. The sensitivity and specificity of E7-MPG and/or E6 antibodies to detect HPV16-positive CCs were evaluated. HPV16 ctDNA was detected using the E7-MPG in 42.3% of all plasma samples and in 74.7% of plasma samples from HPV16-positive CC cases. The validation of E7-MPG data by ddPCR showed that the sensitivity of the E7-MPG test for HPV16-positive CC detection was higher than that of ddPCR (74.7% versus 63.1%; P < 0.001). When both HPV16 ctDNA and E6 antibodies were considered, the sensitivity for HPV16-positive CC detection increased from 74.7% to 86.1%, while the specificity was unchanged at 97.8%. The performance of E7-MPG for the detection of HPV16 ctDNA appears to be at least as sensitive as that of ddPCR, offering an additional tool for ctDNA detection of HPV16-positive CC. The use of an additional blood marker of HPV infection, such as E6 antibodies, further improved the detection of CC. IMPORTANCE The validity of HPV ctDNA as a marker of HPV-driven cancers has been previously reported. Herein we validated an alternative to ddPCR for HPV16 ctDNA detection, using a bead-based HPV genotyping assay that offers the potential advantage of reducing the cost of clinical management due to the multiplex capability of the test, thus facilitating its use in clinical settings. In addition, we analyzed HPV ctDNA in the context of E6 antibodies as an additional HPV marker. The HPV16 ctDNA biomarker appeared to be highly specific and, to a lesser extent, sensitive for the detection of CC, mainly indicated for those at an advanced tumor stage. In this proof-of-principle study, E6 antibodies were mainly detected in early tumor stages of CC, while HPV ctDNA was mainly positive at advanced tumor stages.

Detection of Host Cell Gene/HPV DNA Methylation Markers: A Promising Triage Approach for Cervical Cancer

Cervical cancer is the most prevalent gynecologic malignancy, especially in women of low- and middle-income countries (LMICs). With a better understanding of the etiology and pathogenesis of cervical cancer, it has been well accepted that this type of cancer can be prevented and treated via early screening. Due to its higher sensitivity than cytology to identify precursor lesions of cervical cancer, detection of high-risk human papillomavirus (HR-HPV) DNA has been implemented as the primary screening approach. However, a high referral rate for colposcopy after HR-HPV DNA detection due to its low specificity in HR-HPV screening often leads to overtreatment and thus increases the healthcare burden. Emerging evidence has demonstrated that detection of host cell gene and/or HPV DNA methylation represents a promising approach for the early triage of cervical cancer in HR-HPV-positive women owing to its convenience and comparable performance to cytology, particularly in LMICs with limited healthcare resources. While numerous potential markers involving DNA methylation of host cell genes and the HPV genome have been identified thus far, it is crucial to define which genes or panels involving host and/or HPV are feasible and appropriate for large-scale screening and triage. An ideal approach for screening and triage of CIN/ICC requires high sensitivity and adequate specificity and is suitable for self-sampling and inexpensive to allow population-based screening, particularly in LMICs. In this review, we summarize the markers of host cell gene/HR-HPV DNA methylation and discuss their triage performance and feasibility for high-grade precancerous cervical intraepithelial neoplasia or worse (CIN2+ and CIN3+) in HR-HPV-positive women.

Known Benefits and Unknown Risks of Active Surveillance of Cervical Intraepithelial Neoplasia Grade 2

Cervical intraepithelial neoplasia grade 2 (CIN 2) is an equivocal diagnosis with high interobserver variation. Owing to high regression rates of 50%, many countries recommend active surveillance of CIN 2, especially in women younger than age 25-30 years, where regression rates are even higher (ie, 60%). Additionally, excisional treatment is associated with increased risk of reproductive harm, particularly preterm birth. Active surveillance typically consists of semi-annual follow-up visits for up to 2 years, including colposcopy and either cytology, testing for human papillomavirus, or both. Excisional treatment is recommended for progression or persistent disease after 2 years. Because active surveillance in younger women is relatively new, knowledge on subsequent risk of cervical cancer is limited. Considering human papillomavirus latency, women undergoing active surveillance might be at higher risk of cervical cancer than women undergoing excisional treatment. Furthermore, there are limited data describing preferences of women for the management of CIN 2, and it is also unclear how active surveillance may affect planning for future pregnancy. In this context, biomarkers for risk stratification of CIN 2 into either high or low probability of progression would allow for targeted treatment. Currently, immunohistochemical staining for p16 is used to clarify the histologic diagnosis, but whether it or other biomarkers can be used for risk-stratification in clinical management of women with CIN 2 remains unknown. In conclusion, active surveillance of CIN 2 needs further investigation, including understanding the long-term cervical cancer risk and evaluation of markers that may enable risk stratification of CIN 2.

HPV prevention and control - The way forward

The global confrontation with COVID-19 has not only diverted current healthcare resources to deal with the infection but has also resulted in increased resources in the areas of testing and screening, as well as educating most of the global public of the benefits of vaccination. When the COVID-19 pandemic eventually recedes, the opportunity must not be missed to ensure that these newly created resources are maintained and redeployed for use in testing and immunisation against other vaccine-preventable infectious diseases. A notable example is infection by human papillomavirus (HPV), the commonest sexually transmitted human virus and the leading cause of a variety of cancers in both men and women, such as cervical, head and neck, anal, vaginal, vulvar and penile cancers. The most important is cervical cancer, the objective of the global elimination goals targeting the vaccination of young female and male adolescents, screening all women and treatment of all infected women. As the campaigns to control SARS-CoV-2, the eradication of HPV-induced cancers also relies on effective prevention and control programs. The lessons learned and the technical, logistical and human resources which have been established to combat COVID-19 by vaccination and testing must be applied to the eradication of other infections which affect the global population. This commentary summarizes the opportunities that the COVID-19 pandemic has created for HPV prevention and control, lists the already available tools for HPV control, and emphasizes the potential public health threats amidst the ongoing COVID-19 pandemic.

STRIDES - STudying Risk to Improve DisparitiES in Cervical Cancer in Mississippi - Design and baseline results of a Statewide Cohort Study

Cervical cancer rates in Mississippi are disproportionately high, particularly among Black individuals; yet, research in this population is lacking. We designed a statewide, racially diverse cohort of individuals undergoing cervical screening in Mississippi. Here, we report the baseline findings from this study. We included individuals aged 21 years and older undergoing cervical screening with cytology or cytology-human papillomavirus (HPV) co-testing at the Mississippi State Health Department (MSDH) and the University of Mississippi Medical Center (UMMC) (December 2017-May 2020). We collected discarded cytology specimens for future biomarker testing. Demographics and clinical results were abstracted from electronic medical records and evaluated using descriptive statistics and chi-square tests. A total of 24,796 individuals were included, with a median age of 34.8 years. The distribution of race in our cohort was 60.2% Black, 26.4% White, 7.5% other, and 5.9% missing. Approximately 15% had abnormal cytology and, among those who underwent co-testing at MSDH (n = 6,377), HPV positivity was 17.4% and did not vary significantly by race. Among HPV positives, Black individuals were significantly less likely to be HPV16/18 positive and more likely to be positive for other high-risk 12 HPV types compared to White individuals (20.5% vs. 27.9%, and 79.5% and 72.1%, respectively, p = 0.011). Our statewide cohort represents one of the largest racially diverse studies of cervical screening in the U.S. We show a high burden of abnormal cytology and HPV positivity, with significant racial differences in HPV genotype prevalence. Future studies will evaluate cervical precancer risk, HPV genotyping, and novel biomarkers in this population.

The Improving Risk Informed HPV Screening (IRIS) Study: Design and Baseline Characteristics

BACKGROUND

Cervical cancer screening with high-risk HPV (HrHPV) testing is being introduced. Most HrHPV infections are transient, requiring triage tests to identify individuals at highest risk for progression to cervical cancer. Head-to-head comparisons of available strategies for screening and triage are needed. Endometrial and ovarian cancers could be amenable to similar testing.

METHODS

Between 2016-2021 discard cervical cancer screening specimens from women ages 25-65 undergoing screening at Kaiser Permanente Northern California were collected. Specimens were aliquoted, stabilized, and stored frozen. HPV, cytology and histopathology results as well as demographic and co-factor information were obtained from electronic medical records. Follow-up collection of specimens was conducted for 2 years and EMR-based data collection was planned five years.

RESULTS

Collection of enrollment and follow-up specimens are complet and EMR-based follow-up data collection is ongoing. At baseline, specimens were collected from 54,971 HPV-positive, 10,219 HPV-negative/Pap-positive and 12,751 HPV-negative/Pap-negative women. Clinical history prior to baseline was available for 72.6% of individuals, of which 53.9% were undergoing routine screening, 8.6% recently had an abnormal screen, 30.3% had previous colposcopy, and 7.2% had previous treatment. As of November 2020, 55.6% had one or more colposcopies, yielding 5,515 CIN2, 2,735 CIN3 and 147 cancer histopathology diagnoses.

CONCLUSIONS

This robust population-based cohort study represents all stages of cervical cancer screening, management, and post-treatment follow-up.

IMPACT

The IRIS study is a unique and highly relevant resource allowing for natural history studies and rigorous evaluation of candidate HrHPV screening and triage markers, while permitting studies of biomarkers associated with other gynecological cancers.

Viral Causality of Human Cancer and Potential Roles of Human Endogenous Retroviruses in the Multi-Omics Era: An Evolutionary Epidemiology Review

Being responsible for almost 12% of cancers worldwide, viruses are among the oldest known and most prevalent oncogenic agents. The quality of the evidence for the in vivo tumorigenic potential of microorganisms varies, thus accordingly, viruses were classified in 4 evidence-based categories by the International Agency for Research on Cancer in 2009. Since then, our understanding of the role of viruses in cancer has significantly improved, firstly due to the emergence of high throughput sequencing technologies that allowed the “brute-force” recovery of unknown viral genomes. At the same time, multi-omics approaches unravelled novel virus-host interactions in stem-cell biology. We now know that viral elements, either exogenous or endogenous, have multiple sometimes conflicting roles in human pathophysiology and the development of cancer. Here we integrate emerging evidence on viral causality in human cancer from basic mechanisms to clinical studies. We analyze viral tumorigenesis under the scope of deep-in-time human-virus evolutionary relationships and critically comment on the evidence through the eyes of clinical epidemiology, firstly by reviewing recognized oncoviruses and their mechanisms of inducing tumorigenesis, and then by examining the potential role of integrated viruses in our genome in the process of carcinogenesis.

Epigenetic approaches for cervical neoplasia screening (Review)

Human papillomavirus (HPV) infection is the leading cause of cervical cancer. The Papanicolaou cytology test is the usually employed type of screening for this infection; however, its sensibility is limited. Only a small percentage of women infected with high-risk HPV develop cervical cancer with an array of genetic and epigenetic modifications. Thus, it is necessary to develop rapid, reproducible and minimally invasive technologies for screening. DNA methylation has gained attention as an alternative method for molecular diagnosis and prognosis in HPV infection. The aim of the present review was to highlight the potential of DNA methylation in cervical neoplasia screening for clinical applications. It was observed that the methylation human and viral genes was correlated with high-grade lesions and cancer. Methylation biomarkers have shown a good capacity to discriminate between high-grade lesions with a transformative potential and cervical cancer, being able to detect these modifications at an early stage. With further research, the epigenetic profiles and subtypes of the tumors could be elaborated, which would aid in therapy selection by opening avenues in personalized precision medicine. Response to therapy could also be evaluated through such methods and the accessibility of liquid biopsies would allow a constant monitoring of the patient's status without invasive sampling techniques.

Moving towards a strategy to accelerate cervical cancer elimination in a high-burden city-Lessons learned from the Amazon city of Manaus, Brazil

The World Health Organization Call to Eliminate Cervical Cancer resonates in cities like Manaus, Brazil, where the burden is among the world's highest. Manaus has offered free cytology-based screening since 1990 and HPV immunization since 2013, but the public system is constrained by many challenges and performance is not well-defined. We obtained cervical cancer prevention activities within Manaus public health records for 2019 to evaluate immunization and screening coverage, screening by region and neighborhood, and the annual Pink October screening campaign. We estimated that among girls and boys age 14-18, 85.9% and 64.9% had 1+ doses of HPV vaccine, higher than rates for age 9-13 (73.4% and 43.3%, respectively). Of the 90,209 cytology tests performed, 24.9% were outside the target age and the remaining 72,230 corresponded to 40.1% of the target population (one-third of women age 25-64). The East zone had highest screening coverage (49.1%), highest high-grade cytology rate (2.5%) and lowest estimated cancers (38.1/100,000) compared with the South zone (32.9%, 1.8% and 48.5/100,000, respectively). Largest neighborhoods had fewer per capita screening locations, resulting in lower coverage. During October, some clinics successfully achieved higher screening volumes and high-grade cytology rates (up to 15.4%). Although we found evidence of some follow-up within 10 months post-screening for 51/70 women (72.9%) with high-grade or worse cytology, only 18 had complete work-up confirmed. Manaus has successfully initiated HPV vaccination, forecasting substantial cervical cancer reductions by 2050. With concerted efforts during campaigns, some clinics improved screening coverage and reached high-risk women. Screening campaigns in community locations in high-risk neighborhoods using self-collected HPV testing can achieve widespread coverage. Simplifying triage and treatment with fewer visits closer to communities would greatly improve follow-up and program effectiveness. Achieving WHO Cervical Cancer Elimination goals in high-burden cities will require major reforms for screening and simpler follow-up and treatment.

Rethinking Cervical Cancer Screening in Brazil Post COVID-19: A Global Opportunity to Adopt Higher Impact Strategies

The World Health Organization global call to eliminate cervical cancer encourages countries to consider introducing or improving cervical cancer screening programs. Brazil's Unified Health System (SUS) is among the world's largest public health systems offering free cytology testing, follow-up colposcopy, and treatment. Yet, health care networks across the country have unequal infrastructure, human resources, equipment, and supplies resulting in uneven program performance and large disparities in cervical cancer incidence and mortality. An effective screening program needs multiple strategies feasible for each community's reality, facilitating coverage and follow-up adherence. Prioritizing those at highest risk with tests that better stratify risk will limit inefficiencies, improving program impact across different resource settings. Highly sensitive human papillomavirus (HPV)-DNA testing performs better than cytology and, with self-collection closer to homes and workplaces, improves access, even in remote regions. Molecular triage strategies like HPV genotyping can identify from the same self-collected sample, those at highest risk requiring follow-up. If proven acceptable, affordable, cost-effective, and efficient in the Brazilian context, these strategies would increase coverage while removing the need for speculum exams for routine screening and reducing follow-up visits. SUS could implement a nationwide organized program that accommodates heterogenous settings across Brazil, informing a variety of screening programs worldwide.

Association of Asthma and Rhinitis with Epigenetics of Coronavirus Related Genes

Introduction:

Susceptibility factors for coronavirus disease 2019 (COVID-19) include sex and medical conditions such as asthma and rhinitis. DNA methylation (DNAm) is associated with asthma, rhinitis, and several viruses. We examined associations of asthma/rhinitis with DNAm at CpGs located on coronavirus related genes, and if these associations were sex-specific.

Methods:

In total, n = 242 subjects aged 26 years from the Isle of Wight Birth Cohort were included in the study. Linear regressions were used to examine sex specific and non-specific associations of DNAm at CpGs on coronavirus related genes with asthma/rhinitis status. Associations of DNAm with gene expression in blood were assessed for functional relevance of identified CpGs.

Results:

Statistically significant interaction effects of asthma or rhinitis with sex were identified at 40 CpGs for asthma and 27 CpGs for rhinitis. At 21 CpGs, DNAm was associated with asthma, and at 45 CpGs with rhinitis, regardless of sex. Assessment of functional relevance of the identified CpGs indicated a potential of epigenetic regulatory functionality on gene activity at 14 CpGs for asthma and 17 CpGs for rhinitis, and of those 6 CpGs for asthma and 7 CpGs for rhinitis were likely to be sex-specific.

Conclusion:

Subjects with asthma/rhinitis may have altered susceptibility to COVID-19 due to changes in their DNAm associated with these conditions. Sex specificity on association of asthma/rhinitis with DNAm at certain CpGs, and on the association of DNAm at asthma/rhinitis-linked CpGs with gene expression have the potential to explain the reported sex-specificity in COVID-19 morbidity and mortality.

Phylogenomic Analysis of Human Papillomavirus Type 31 and Cervical Carcinogenesis: A Study of 2093 Viral Genomes

Human papillomavirus (HPV) type 31 (HPV31) is closely related to the most carcinogenic type, HPV16, but only accounts for 4% of cervical cancer cases worldwide. Viral genetic and epigenetic variations have been associated with carcinogenesis for other high-risk HPV types, but little is known about HPV31. We sequenced 2093 HPV31 viral whole genomes from two large studies, one from the U.S. and one international. In addition, we investigated CpG methylation in a subset of 175 samples. We evaluated the association of HPV31 lineages/sublineages, single nucleotide polymorphisms (SNPs) and viral methylation with cervical carcinogenesis. HPV31 A/B clade was >1.8-fold more associated with cervical intraepithelial neoplasia grade 3 and cancer (CIN3+) compared to the most common C lineage. Lineage/sublineage distribution varied by race/ethnicity and geographic region. A viral genome-wide association analysis identified SNPs within the A/B clade associated with CIN3+, including H23Y (C626T) (odds ratio = 1.60, confidence intervals = 1.17-2.19) located in the pRb CR2 binding-site within the E7 oncogene. Viral CpG methylation was higher in lineage B, compared to the other lineages, and was most elevated in CIN3+. In conclusion, these data support the increased oncogenicity of the A/B lineages and suggest variation of E7 as a contributing risk factor.

Human papillomavirus 16 L1 gene methylation as a potential biomarker for predicting anal intraepithelial neoplasia in men who have sex with men (MSM)

The human papillomavirus (HPV) 16 early promoter and L1 gene methylation were quantitatively measured using pyrosequencing assay in anal cells collected from men who have sex with men (MSM) to determine potential biomarkers for HPV-related anal cancer. The methylation patterns of HPV16 genes, including the early promoter (CpG 31, 37, 43, 52, and 58) and L1 genes (CpG 5600, 5606, 5609, 5615, 7136, and 7145), were analyzed in 178 anal samples. The samples were diagnosed as normal, anal intraepithelial neoplasia (AIN) 1, AIN2, and AIN3. Low methylation levels of the early promoter (< 10%) and L1 genes (< 20%) were found in all detected normal anal cells. In comparison, medium to high methylation (≥ 20–60%) in the early promoter was found in 1.5% (1/67) and 5% (2/40) of AIN1 and AIN2-3 samples, respectively. Interestingly, slightly increased L1 gene methylation levels (≥ 20–60%), especially at the HPV16 5’L1 regions CpGs 5600 and 5609, were demonstrated in AIN2-3 specimen. Moreover, a negative correlation between high HPV16 L1 gene methylation at CpGs 5600, 5609, 5615, and 7145 and a percentual CD4 count was found in AIN3 HIV positive cases. When comparing the methylation status of AIN2-3 to that of normal/AIN1 lesions, the results indicated the potential of using HPV16 L1 gene methylation as a biomarker for HPV-related cancer screening.

Outcomes of women with positive oncogenic HPV and reflex cytology showing possible high-grade squamous intraepithelial lesion

AIM

To examine outcomes in women following cervical screening detection of oncogenic human papillomavirus (HPV), with reflex cytology showing possible high-grade squamous intraepithelial lesion (pHSIL).

MATERIALS AND METHODS

A retrospective observational study of 523 women seen in the Royal Women's Hospital Colposcopy Clinic from 1 January 2018 to 31 July 2020.

RESULTS

Two hundred eighty-two (53.9%) women had histology-confirmed HSIL, encompassing CIN2 or worse (CIN2+), including seven cancers (1.3%) and two adenocarcinoma in situ (AIS) (0.4%). In 81.2% (229/282) of women with CIN2+, this was detected on cervical biopsy at initial colposcopy, with another 8.9% (25/282) of CIN2+ detected at cervical excision following initial colposcopy and the remaining 9.9% (28/282) at follow-up colposcopy thereafter. When discordant cervical biopsy results were discussed at multidisciplinary meeting (MDM), 66.7% of women with pHSIL cytology upgraded to definite HSIL were found to have CIN2+, but only 20.8% when pHSIL cytology was retained and none when downgraded to low-grade (LSIL) or normal. No significant difference was found in the proportion of CIN2+ based on patient age above or below 40, HPV16 and/or 18 versus non 16/18, or whether discordant findings were reviewed at MDM.

CONCLUSIONS

We propose a pathway for management of women with positive oncogenic HPV and reflex pHSIL cytology. MDM review is recommended when CIN2+ is not identified on cervical biopsy at initial colposcopy. Conservative management is safe with low risk of CIN2+ when LBC prediction of pHSIL is confirmed or downgraded at MDM with no high-grade change on colposcopy or repeat cytology.

Emerging technologies for cervical cancer screening

Cervical cancer remains a concern worldwide, and cervical cancer screening plays an important role in reducing the burden of this disease. Although cytology is still the main strategy for cervical cancer screening, it has gradually changed to human papillomavirus testing. The specificity of human papillomavirus testing is lower than that of cytology, which leads to an increased rate of colposcopy after positive results. To decrease colposcopic examinations, an efficient triage method is needed for human papillomavirus screening. New biomarkers have been developed and evaluated for primary screening and triage of abnormal cytology or human papillomavirus-positive results. Their sensitivity and specificity were estimated and compared with those of cytology. In the present study, the following new techniques were examined: p16/Ki67 dual staining, DNA methylation, micro-ribonucleic acid, chromosomal abnormalities, Claudins and DNA ploidy. Evaluation studies of p16/Ki67 dual staining and DNA methylation were more advanced than those of other options. When p16/Ki67 dual staining was used for triage for human papillomavirus testing, the sensitivity of 2 or greater cervical intraepithelial neoplasia (CIN2+) detection was higher than that of cytology without decreased specificity. Although there are several types of DNA methylation, sensitivity and specificity were moderate for detecting CIN2+. S5 classifier is a commercialized product that consists of viral methylation, and high sensitivity with decreased specificity has been reported. Considering its combination with self-sampling, DNA methylation is a highly anticipated technique along with human papillomavirus testing for the next generation of cervical cancer screening. However, the backgrounds for cervical cancer screening differ among countries and further study is needed to identify the best available method.

Genetic and Epigenetic Variations of HPV52 in Cervical Precancer

The goal of this study was to identify human papillomavirus (HPV) type 52 genetic and epigenetic changes associated with high-grade cervical precancer and cancer. Patients were selected from the HPV Persistence and Progression (PaP) cohort, a cervical cancer screening program at Kaiser Permanente Northern California (KPNC). We performed a nested case-control study of 89 HPV52-positive women, including 50 cases with predominantly cervical intraepithelial neoplasia grade 3 (CIN3) and 39 controls without evidence of abnormalities. We conducted methylation analyses using Illumina sequencing and viral whole genome Sanger sequencing. Of the 24 CpG sites examined, increased methylation at CpG site 5615 in HPV52 L1 region was the most significantly associated with CIN3, with a difference in median methylation of 17.9% (odds ratio (OR) = 4.8, 95% confidence interval (CI) = 1.9–11.8) and an area under the curve of 0.73 (AUC; 95% CI = 0.62–0.83). Complete genomic sequencing of HPV52 isolates revealed associations between SNPs present in sublineage C2 and a higher risk of CIN3, with ORs ranging from 2.8 to 3.3. This study identified genetic and epigenetic HPV52 variants associated with high risk for cervical precancer, improving the potential for early diagnosis of cervical neoplasia caused by HPV52.

The role of HPV-induced epigenetic changes in cervical carcinogenesis (Review)

Cervical cancer is associated with infection by certain types of human papillomaviruses (HPVs), and this affects women worldwide. Despite the improvements in prevention and cure of HPV-induced cervical cancer, it remains the second most common type of cancer in women in the least developed regions of the world. Epigenetic modifications are stable long-term changes that occur in the DNA, and are part of a natural evolutionary process of necessary adaptations to the environment. They do not result in changes in the DNA sequence, but do affect gene expression and genomic stability. Epigenetic changes are important in several biological processes. The effects of the environment on gene expression can contribute to the development of numerous diseases. Epigenetic modifications may serve a critical role in cancer cells, by silencing tumor suppressor genes, activating oncogenes, and exacerbating defects in DNA repair mechanisms. Although cervical cancer is directly related to a persistent high-risk HPV infection, several epigenetic changes have been identified in both the viral DNA and the genome of the infected cells: DNA methylation, histone modification and gene silencing by non-coding RNAs, which initiate and sustain epigenetic changes. In the present review, recent advances in the role of epigenetic changes in cervical cancer are summarized.

Primary HPV cervical screening: Clinical audit of outcomes of women seen at a tertiary referral centre for colposcopy in Australia

BACKGROUND

Primary human papillomavirus (HPV) screening was introduced in Australia in December 2017.

AIMS

Outcomes for women after positive HPV in their cervical screening test (CST).

MATERIALS AND METHODS

A retrospective observational study of 4458 women seen at the Royal Women's Hospital Colposcopy Clinic from 1 January 2018 to 31 July 2020.

RESULTS

HPV16/18 was positive (considered higher-risk CST) in 42.2% of women in the study, 16.6% with reflex possible with high-grade squamous intraepithelial lesions (pHSIL) or worse and 54.9% with normal cytology. There were 24.8% of women with positive HPV16/18 who had histological confirmed cervical intraepithelial neoplasia grade 2 or worse (CIN2+), 10.3% CIN2+ (including six cancers) among women with reflex negative cytology and 87.7% CIN2+ among women with reflex HSIL cytology. In women with positive HPV (not 16/18), CIN2+ was found in 60.2% with reflex pHSIL or worse cytology (higher risk) and 10.2% with reflex low-grade SIL (LSIL) or normal cytology (intermediate risk). Median waiting time to colposcopy with the intermediate-risk group went up to 181 days. Our colposcopists were able to achieve a positive predictive value (PPV) for CIN2+ of 69.9%, higher than 57.8% PPV in the National Cervical Screening Program (NCSP) 2020 monitoring report. Women with type 3 transformation zone on colposcopy could be followed up with CST if no HSIL was suspected on screening or at colposcopy as their risk of CIN2+ was only 2.5%.

CONCLUSIONS

Our findings support direct referral to colposcopy for women with higher-risk CST, with all cancers confined to this group. The NCSP recommendation to refer for colposcopy only after three intermediate-risk CST will need monitoring with the LSIL triage group.

Is group testing ready for prime-time in disease identification?

Large-scale disease screening is a complicated process in which high costs must be balanced against pressing public health needs. When the goal is screening for infectious disease, one approach is group testing in which samples are initially tested in pools and individual samples are retested only if the initial pooled test was positive. Intuitively, if the prevalence of infection is small, this could result in a large reduction of the total number of tests required. Despite this, the use of group testing in medical studies has been limited, largely due to skepticism about the impact of pooling on the accuracy of a given assay. While there is a large body of research addressing the issue of testing errors in group testing studies, it is customary to assume that the misclassification parameters are known from an external population and/or that the values do not change with the group size. Both of these assumptions are highly questionable for many medical practitioners considering group testing in their study design. In this article, we explore how the failure of these assumptions might impact the efficacy of a group testing design and, consequently, whether group testing is currently feasible for medical screening. Specifically, we look at how incorrect assumptions about the sensitivity function at the design stage can lead to poor estimation of a procedure's overall sensitivity and expected number of tests. Furthermore, if a validation study is used to estimate the pooled misclassification parameters of a given assay, we show that the sample sizes required are so large as to be prohibitive in all but the largest screening programs.