Policy analysis of cervical cancer screening strategies in low-resource settings: clinical benefits and cost-effectiveness

Modelling epidemiological and economics processes - the case of cervical cancer

Different types of mathematical models can be used to forecast the development of diseases as well as associated costs and analyse the cost-effectiveness of interventions. The set of models available to assess these parameters, reach from simple independent equations to highly complex agent-based simulations. For many diseases, it is simple to distinguish between infectious diseases and chronic-degenerative diseases. For infectious diseases, dynamic models are most appropriate because they allow for feedback from the number of infected to the number of new infections, while for the latter Markov models are more appropriate since this feedback is not required. However, for some diseases, the aforementioned distinction is not as clear. Cervical cancer, for instance, is caused by a sexually transmitted virus, and therefore falls under the definition of an infectious disease. However, once infected, the condition can progress to a chronic disease. Consequently, cervical cancer could be considered an infectious or a chronic-degenerative disease, depending on the stage of infection. In this paper, we will analyse the applicability of different mathematical models for epidemiological and economic processes focusing on cervical cancer. For this purpose, we will present the basic structure of different models. We will then conduct a literature analysis of the mathematical models used to predict the spread of cervical cancer. Based on these findings we will draw conclusions about which models can be used for which purpose and which disease. We conclude that each type of model has its advantages and disadvantages, but the choice of model type often seems arbitrary. In the case of cervical cancer, homogenous Markov models seem appropriate if a cohort of newly infected is followed for a shorter period, for instance, to assess the impact of screening programs. For long-term consequences, such as the impact of a vaccination program, a feedback loop from former infections to the future likelihood of infections is required. This can be done using system dynamics or inhomogeneous Markov models. Discrete event or agent-based simulations can be used in the case of cervical cancer when small cohorts or specific characteristics of individuals are required. However, these models require more effort than Markov or System Dynamics models.

Acceptability and feasibility of implementing thermal ablation as a preventive cervical cancer treatment and the comparison of treatment outcome with cryotherapy in Zimbabwe

Introduction and background

Thermal ablation, a technique that destroys precancerous cervical cells by extreme heat or cold, is predominantly used as a preventive cervical cancer treatment modality in high-income countries. Compared to other treatment methods thermal ablation has numerous advantages in its portability, minimal electricity use and comparable treatment rates, which is convenient for use in low- and middle-income countries (LMICs). Therefore, it is important to understand acceptability among providers and clients and the feasibility of achieving comparable treatment outcomes with other methods in LMICs.

Methodology

We conducted a prospective longitudinal, open-label two-arm study from June 2021 to April 2022 at seven health delivery points. In this study, 182 clients were enrolled to receive preventive cancer treatment at baseline and followed up 6 months later to measure treatment outcomes and experiences on the procedure. Eligible consented clients were elected to a preferred method (either thermal ablation as an intervention or cryotherapy as a control group). We also conducted qualitative interviews with 14 service providers in either static or outreach settings.

Results

At the 6-month follow-up, the efficacy was comparable among the two groups, 96.5% (95% CI 86.7%-99.1%) clients in the intervention group had successful lesion treatment rate compared to 80.8% (95% CI 69.9%-99.1%) of the control group. Furthermore, 99% of clients in the intervention group would recommend thermal ablation to their family members or peers. Service providers preferred thermal ablation due to its ease of use, lower costs, portability and lower likelihood of adverse events compared to cryotherapy.

Conclusion

The study showed the feasibility of implementing thermal ablation as a new preventive cervical cancer treatment modality in Zimbabwe. Furthermore, service providers indicated their preference for thermal ablation due to its ease of use, portability at static settings and lower likelihood of adverse events occurrence. Therefore, we recommend scaling up thermal ablation both at static and outreach sites.

Cost-effectiveness of approaches to cervical cancer screening in Malawi: comparison of frequencies, lesion treatment techniques, and risk-stratified approaches

BACKGROUND

Recently-updated global guidelines for cervical cancer screening incorporated new technologies-most significantly, the inclusion of HPV DNA detection as a primary screening test-but leave many implementation decisions at countries' discretion. We sought to develop recommendations for Malawi as a test case since it has the second-highest cervical cancer burden globally and high HIV prevalence. We incorporated updated epidemiologic data, the full range of ablation methods recommended, and a more nuanced representation of how HIV status intersects with cervical cancer risk and exposure to screening to model outcomes of different approaches to screening.

METHODS

Using a Markov model, we estimate the relative health outcomes and costs of different approaches to cervical cancer screening among Malawian women. The model was parameterized using published data, and focused on comparing "triage" approaches-i.e., lesion treatment (cryotherapy or thermocoagulation) at differing frequencies and varying by HIV status. Health outcomes were quality-adjusted life years (QALYs) and deaths averted. The model was built using TreeAge Pro software.

RESULTS

Thermocoagulation was more cost-effective than cryotherapy at all screening frequencies. Screening women once per decade would avert substantially more deaths than screening only once per lifetime, at relatively little additional cost. Moreover, at this frequency, it would be advisable to ensure that all women who screen positive receive treatment (rather than investing in further increases in screening frequency): for a similar gain in QALYs, it would cost more than four times as much to implement once-per-5 years screening with only 50% of women treated versus once-per-decade screening with 100% of women treated. Stratified screening schedules by HIV status was found to be an optimal approach.

CONCLUSIONS

These results add new evidence about cost-effective approaches to cervical cancer screening in low-income countries. At relatively infrequent screening intervals, if resources are limited, it would be more cost-effective to invest in scaling up thermocoagulation for treatment before increasing the recommended screening frequency. In Malawi or countries in a similar stage of the HIV epidemic, a stratified approach that prioritizes more frequent screening for women living with HIV may be more cost-effective than population-wide recommendations that are HIV status neutral.

Lightweight Low-Rank Adaptation Vision Transformer Framework for Cervical Cancer Detection and Cervix Type Classification

Cervical cancer is a major health concern worldwide, highlighting the urgent need for better early detection methods to improve outcomes for patients. In this study, we present a novel digital pathology classification approach that combines Low-Rank Adaptation (LoRA) with the Vision Transformer (ViT) model. This method is aimed at making cervix type classification more efficient through a deep learning classifier that does not require as much data. The key innovation is the use of LoRA, which allows for the effective training of the model with smaller datasets, making the most of the ability of ViT to represent visual information. This approach performs better than traditional Convolutional Neural Network (CNN) models, including Residual Networks (ResNets), especially when it comes to performance and the ability to generalize in situations where data are limited. Through thorough experiments and analysis on various dataset sizes, we found that our more streamlined classifier is highly accurate in spotting various cervical anomalies across several cases. This work advances the development of sophisticated computer-aided diagnostic systems, facilitating more rapid and accurate detection of cervical cancer, thereby significantly enhancing patient care outcomes.

Exploring computer-aided health decision-making on cervical cancer interventions through deliberative interviews in Ethiopia

Cervical cancer is a significant disease burden in Ethiopia. Mathematical models and computer simulations on disease dynamics can support effective resource allocation. The objectives of this work are (i) to explore the perspectives of health decision-makers on computer-aided predictions supporting cervical cancer interventions, (ii) to identify their information needs from these predictions, and (iii) their willingness to apply the results in their work. We conducted deliberative interviews with 15 health decision-makers and advisors in Ethiopia in autumn 2019. We analyze the data using a five steps framework approach drawing on thematic analysis and find that Ethiopian health decision-makers are willing to use computer-aided predictions in their decisions. Data on HPV prevalence and the cervical cancer burden are scarce but valued highly and decision-makers are particularly interested in the identification of local HPV hotspots. Data-driven mathematical models and computer simulations may increasingly influence health decision-making in Ethiopia.

Cervical cancer in Nepal: Current screening strategies and challenges

Nepal has a high burden of cervical cancer primarily due to a limited screening program. Most present with advanced cervical disease. Despite no national cervical cancer control program, Nepal's Ministry of Health and Population has taken many initiatives with various international collaborations in screening, vaccination, and treating pre-invasive and invasive cancer. However, the existing prevention and treatment modalities are dismally inadequate to meet the targets of WHO's cervical cancer eliminative initiative by 2030. We provide an overview of the Ministry of Health and Population, Nepal's efforts to tackle the growing cervical cancer burden in the country. We discuss the challenges and potential solutions that could be practical and augment screening uptakes, such as single-dose vaccination and HPV DNA tests. The screen-and-treat approach on the same day could potentially address treatment delays and follow-up loss after testing positive. Our narrative summary highlights existing and innovative strategies, unmet needs, and collaborations required to achieve elimination across implementation contexts.

Mathematical Models for Evaluating Effectiveness and Cost-Effectiveness of Cervical Cancer Control Policies in Populations Including Women Living With Human Immunodeficiency Virus: A Scoping Review

OBJECTIVES

Mathematical modeling is increasingly used to inform cervical cancer control policies, and model-based evaluations of such policies in women living with human immunodeficiency virus (HIV) are an emerging research area. We did a scoping review of published literature to identify research gaps and inform future work in this field.

METHODS

We systematically searched literature up to April 2022 and included mathematical modeling studies evaluating the effectiveness or cost-effectiveness of cervical cancer prevention strategies in populations including women living with HIV. We extracted information on prevention strategies and modeling approaches.

RESULTS

We screened 1504 records and included 22 studies, almost half of which focused on South Africa. We found substantial between-study heterogeneity in terms of strategies assessed and modeling approaches used. Fourteen studies evaluated cervical cancer screening strategies, 7 studies assessed human papillomavirus vaccination (with or without screening), and 1 study evaluated the impact of HIV control measures on cervical cancer incidence and mortality. Thirteen conducted cost-effectiveness analyses. Markov cohort state-transition models were used most commonly (n = 12). Most studies (n = 17) modeled the effect of HIV by creating HIV-related health states. Thirteen studies performed model calibration, but 11 did not report the calibration methods used. Only 1 study stated that model code was available upon request.

CONCLUSIONS

Few model-based evaluations of cervical cancer control strategies have specifically considered women living with HIV. Improvements in model transparency, by sharing information and making model code publicly available, could facilitate the utility of these evaluations for other high disease-burden countries, where they are needed for assisting policy makers.

Advance Care Planning Documentation and Intensity of Care at the End of Life for Adults With Congestive Heart Failure, Chronic Kidney Disease, and Both Illnesses

CONTEXT

Heart failure (HF) and chronic kidney disease (CKD) are associated with high morbidity and mortality, especially in combination, yet little is known about the impact of these conditions together on end-of-life care.

OBJECTIVES

Compare end-of-life care and advance care planning (ACP) documentation among patients with both HF and CKD to those with either condition.

METHODS

We conducted a retrospective analysis of deceased patients (2010-2017) with HF and CKD (n = 1673), HF without CKD (n = 2671), and CKD without HF (n = 1706), excluding patients with cancer or dementia. We compared hospitalizations and intensive care unit (ICU) admissions in the last 30 days of life, hospital deaths, and ACP documentation >30 days before death.

RESULTS

39% of patients with HF and CKD were hospitalized and 33% were admitted to the ICU in the last 30 days vs. 30% and 28%, respectively, for HF, and 26% and 23% for CKD. Compared to patients with both conditions, those with only 1 were less likely to be admitted to the hospital [HF: adjusted odds ratio (aOR) 0.72, 95%CI 0.63-0.83; CKD: aOR 0.63, 95%CI 0.53-0.75] and ICU (HF: aOR 0.83, 95%CI 0.71-0.94; CKD: aOR 0.68, 95%CI 0.56-0.80) and less likely to have ACP documentation (aOR 0.53, 95%CI 0.47-0.61 and aOR 0.70, 95%CI 0.60-0.81).

CONCLUSIONS

Decedents with both HF and CKD had more ACP documentation and received more intensive end-of-life care than those with only 1 condition. These findings suggest that patients with co-existing HF and CKD may benefit from interventions to ensure care received aligns with their goals.

Comparative assessment of test characteristics of cervical cancer screening methods for implementation in low-resource settings

Cervical cancer disproportionately affects low-resource settings. Papanicolaou, human papillomavirus (HPV), and visual inspection of cervix with acetic acid (VIA) testing, each with different characteristics, will reduce cervical cancer burden. We conducted a critical literature review using PubMed, Cochrane, WHO, and grey literature from 1994 to 2020. We examined efficacy, harms, and comparative effectiveness of screening methods by age, human immunodeficiency virus, provider characteristics, and assessed implementation challenges in low-resource settings. Comprehensive data on utility and efficacy of screening tests indicates that each screening has strengths and shortcomings but all confer acceptable performance. HPV and VIA appear more promising. Primary HPV test-and-treat, self-testing, and co-testing have been studied but data on triage plans, cost, support system, implementation and sustainability is unclear in low-resource settings. HPV testing could help target subgroups of older or higher risk women. VIA offers local capacity-building and scalability. Quality VIA technique after HPV testing is still required to guide post-screening treatments. VIA competencies decline gradually with current standard trainings. Stationary cervicography improves VIA quality but isn't scalable. Affordable smartphones eliminate this barrier, enhance training through mentorship, and advance continuing education and peer-to-peer training. Smartphone-based VIA facilitates cervical image storage for patient education, health promotion, record-keeping, follow-up care, remote expert support, and quality control to improve VIA reliability and reproducibility and reduce mis-diagnoses and burden to health systems. Rather than ranking screening methods using test characteristics alone in study or higher-resource settings, we advocate for scalable strategies that maximize reliability and access and reduce cost and human resources.

At what age should the Uyghur minority initiate cervical cancer screening if screened using careHPV

Background

The careHPV test as a primary screening method for cervical cancer has been proven to be the best option for Uyghur women in Xinjiang in a previous study. In this research, we aim to discuss the appropriate age for Uyghur women in Xinjiang to be screened for cervical cancer using careHPV.

Methods

Eleven thousand women aged 20–69 years old (mean age 38.93 ± 9.74) from South Xinjiang were screened using careHPV and liquid‐based cytology, and the positive results were referred for colposcopy and cervical biopsy. A questionnaire regarding basic social characteristics, sexual practices, and reproductive history was administered to each woman. The age‐specific prevalence of HPV positivity, cytology abnormality, and cervical intraepithelial neoplasia (CIN) 2+ in ≥25, ≥30, and ≥35 age groups were analyzed, and the diagnostic value of careHPV in the three age groups was evaluated. The chi‐squared test was used to compare the differences between age groups. The sensitivity, specificity, positive predictive value, negative predictive value, and area under the receiver operating characteristic curve were calculated.

Results

The women were mostly married (76.3%) and delivered at 15–19 years of age (61.4%). The HPV infection rate was 9.15% and detection rates of CIN2+ and invasive cervical cancer were 1.53% (1530/100,000) and 0.25% (250/100,000), respectively. The first peak of HPV(+) appeared at the age of 30–34, while CIN2+ appeared at 35–39. CareHPV performed similarly well in the three age groups.

Conclusion

Based on the results of our study, Uyghur women in Xinjiang should be recommended to initiate cervical cancer screening at the age of 30 years when screened using careHPV.

Real-world effectiveness of primary screening with high-risk human papillomavirus testing in the cervical cancer screening programme in China: a nationwide, population-based study

BACKGROUND

Randomized controlled trials have shown a higher sensitivity and longer negative predictive value of high-risk human papillomavirus (HPV) testing than cytology for cervical cancer screening; however, little is known about the effectiveness of HPV testing in middle-income countries. Understanding the characteristics of HPV testing may increase the priority of HPV testing in health policies. The study aims to evaluate the effectiveness of HPV testing in the national cervical cancer screening programme in China.

METHODS

We performed a nationwide, population-based study using individual data from the national cervical cancer screening programme in rural China between 2015 and 2017. The analyses included 1,160,981 women aged 35-64 years who underwent cytology alone or high-risk HPV testing with cytology or genotyping triage. The main outcome was cervical intraepithelial neoplasia 2 or worse (CIN2+). We used multivariate logistic regressions and performed sensitivity analyses with propensity score matching to compare the screening positive, colposcopy referral, detection rate, and positive predictive value (PPV).

RESULTS

The screening positive rates for HPV testing and cytology were 10.1% and 4.0%, respectively. The per protocol colposcopy referral rate of HPV testing was significantly lower than that of cytology (3.5% vs 4.0%), and this difference was mostly due to the low referral threshold of cytology (≥ASC-US). Overall, HPV testing detected more CIN2+ (5.5 vs. 4.4 per 1000, adjusted odds ratio [aOR]=1.18, 95% confidence interval 1.11-1.25) and had a higher PPV (13.8% vs 10.9%, aOR 1.29, 95% CI 1.21-1.37) than cytology. The colposcopy referrals of HPV testing in comparison to cytology differed by income status; it significantly increased in lower-middle-income areas (3.7% vs 3.1%, aOR 1.21, 95% CI 1.17-1.25) and significantly decreased in upper-middle-income areas (3.4% vs 4.9%, aOR 0.69, 95% CI 0.67-0.71). Sensitivity analyses demonstrated the reliability and robustness of the results.

CONCLUSIONS

The introduction of HPV testing could improve both the CIN2+ detection rate and efficiency of cervical cancer screening programme, supporting the introduction of primary screening with high-risk HPV testing in China. Further study is needed to investigate the long-term effect of this change.

Implementation of HPV-based screening in Burkina Faso: lessons learned from the PARACAO hybrid-effectiveness study

BACKGROUND

Cervical cancer screening in sub-Saharan countries relies on primary visual inspection with acetic acid (VIA). Primary human papillomavirus (HPV)-based screening is considered a promising alternative. However, the implementation and real-life effectiveness of this strategy at the primary-care level in limited-resource contexts remain under explored. In Ouagadougou, Burkina Faso, free HPV-based screening was implemented in 2019 in two primary healthcare centers. We carried out a process and effectiveness evaluation of this intervention.

METHODS

Effectiveness outcomes and implementation indicators were assessed through a cohort study of screened women, observations in participating centers, individual interviews with women and healthcare providers and monitoring reports. Effectiveness outcomes were screening completeness and women's satisfaction. Logistic regression models and concurrent qualitative analysis explored how implementation variability, acceptability by women and the context affected effectiveness outcomes.

RESULTS

After a 3-month implementation period, of the 350 women included in the cohort, 94% completed the screening, although only 26% had their screening completed in a single visit as planned in the protocol. The proportion of highly satisfied women was higher after result disclosure (95%) than after sampling (65%). A good understanding of the screening results and recommendations increased screening completeness and women's satisfaction, while time to result disclosure decreased satisfaction. Adaptations were made to fit healthcare workers' workload.

CONCLUSION

Free HPV-based screening was successfully integrated within primary care in Ouagadougou, Burkina Faso, leading to a high level of screening completeness despite the frequent use of multiple visits. Future implementation in primary healthcare centers needs to improve counseling and reduce wait times at the various steps of the screening sequence.

Factors related to completion of referral among women with suspected cervical cancer and dysplasia in Tanzania

OBJECTIVE

To investigate completion of referral among women with suspected cervical cancer in Tanzania.

METHODS

Retrospective cohort study of 196 women referred from two healthcare clinics to Ocean Road Cancer Institute, Dar es Salaam, between March 2016 and June 2018. Women with precancerous lesions or suspected cancer were interviewed about their knowledge and perception of cervical cancer and referred for follow-up.

RESULTS

Most participants were unable to name symptoms (55.1%), prevention methods (88.3%), or treatments (59.0%), although 79.1% rated the disease as severe. Women who came for routine early detection were less likely to complete referral than those who did not (odds ratio [OR], 0.18; 95% confidence interval [CI], 0.05-0.70). Women who knew someone who died from cervical cancer were 5.40 times more likely to complete referral than those who did not. Knowing someone with cervical cancer was a predictor of referral completion in three multivariate models: OR, 5.62 (95% CI, 2.20-14.38); 4.34 (1.64-11.47); and 4.61 (1.72-12.36). Having severe symptoms was a predictor of non-completion in two models: 0.30 (0.12-0.75) and 0.35 (0.14-0.87).

CONCLUSION

Patient-directed interventions should include education involving survivors of cancer and dysplasia, whereas system-directed interventions should utilize reminders to increase referral completion.

Outcomes for Step-Wise Implementation of a Human Papillomavirus Testing-Based Cervical Screen-and-Treat Program in El Salvador

PURPOSE

The Cervical Cancer Prevention in El Salvador (CAPE) project is a public-sector intervention introducing lower-cost human papillomavirus (HPV) testing in all four departments of the Paracentral region that screened a total of 28,015 women. After demonstrating success of an HPV screen-and-treat (S&T) algorithm over colposcopy management in the first two phases, the third phase scaled up the S&T strategy. We present results from phase III and evaluate S&T components across the entire project.

METHODS

During phase III, 17,965 women age 30-59 years underwent HPV testing. HPV-positive women were asked to return and, if eligible, received gas-based cryotherapy. We compare loss to follow-up and time intervals between S&T steps across the three phases.

RESULTS

There were no differences in HPV positivity across phases (phase I, 11.9%; phase II, 11.4%; phase III, 12.3%; P = .173). Although most HPV-positive women completed indicated follow-up procedures within 6 months in phases I (93.3%, 111 of 119) and II (92.3%, 429 of 465), this proportion declined to 74.9% (1,659 of 2,214; P < .001) in phase III. Mean days between testing and delivery of results to patients increased over program phases (phase I, 23.2 days; phase II, 46.7 days; phase III, 99.8 days; P < .001).

CONCLUSION

A public-sector implementation of an HPV-based S&T algorithm was successfully scaled up in El Salvador, albeit with losses in efficiency. After CAPE, the Ministry of Health changed its screening guidelines and procured additional tests to expand the program.

Evaluation of cytopathological screening results and risk factors of women who underwent Papanicolaou test in a maternity school in Fortaleza, Ceará, Brazil

INTRODUCTION

Papanicolaou test (Pap smear) is the standard screening test of pre-neoplastic lesions and cervical cancer. This study aimed to investigate cervical cancer screening results and risk factors such as age, reason for the examination, the epithelia detected in the sample, microbiota and signs of sexually transmitted infection (STIs) of women in a maternity school in Fortaleza, Ceará, Brazil.

METHODS

In this cross-sectional study, data were retrieved of 353 women who underwent Pap smear between April 2016 and January 2017 at the Federal University of Ceará.

RESULTS

Of all Pap smear samples retrieved, 54.1% (191/353) had glandular epithelium and 40.2% (142/353) had metaplastic epithelium. After statistical analyses adjusted for the final model, age ≥51 years (odds ratio = 3.47) and signs of STIs (odds ratio = 4.95) remained as risk factors.

CONCLUSIONS

The diagnosis of high-grade lesions and carcinomas in patients older than 50 years indicates a deficiency in cervical screening. Women with signs and symptoms of STIs and candidiasis sought medical services more frequently than asymptomatic women, and presence of these signs and symptoms contributes to the diagnosis of cervical cancer. We highlight the importance of obtaining a correct smear sampling to allow prompt detection of all preneoplastic lesions; moreover, the implementation of human papillomavirus vaccination and an efficient routine Pap screening are necessary in low-resource settings.

Clinical evaluation of modifications to a human papillomavirus assay to optimise its utility for cervical cancer screening in low-resource settings: a diagnostic accuracy study

BACKGROUND

HPV-based screen and treat is the recommended approach for cervical cancer screening in low-resource settings, but quite low specificity of human papillomavirus (HPV) testing, particularly in women living with HIV, leads to overtreatment. We evaluated whether HPV type restriction and more stringent cutoffs on Xpert HPV optimise performance characteristics of this assay for screen and treat.

METHODS

We recruited HIV-negative and HIV-positive women aged 30-65 years from a primary care facility and a referral colposcopy clinic in Cape Town, South Africa. Women included had no history of any anogenital cancer or treatment for cervical dysplasia, had no hysterectomy, and were not pregnancy at the time of recruitment. All women had cervical samples collected for Xpert HPV (an assay that detects high-risk HPV types in five channels: HPV type 16; HPV types 18 or 45, or both; HPV types 31, 33, 35, 52, or 58, or more than one of these types; HPV types 51 or 59, or both; and HPV types 39, 56, 66, or 68, or more than one of these types) and underwent colposcopy and histological sampling with consensus pathology review. Logistic regression and receiver operating characteristic curves were used to evaluate improvements in specificity attained by modifying cycle threshold cutoffs to define screen-positive results.

RESULTS

We recruited 1121 women aged 30-65 years, 586 of whom were HIV-negative and 535 HIV-positive. Sensitivity of detecting cervical intraepithelial neoplasia grade 2 or greater in HIV-negative women using manufacturer-defined cycle threshold cutoffs for all channels was 88·7% (95% CI 83·1-94·3), and specificity was 86·9% (83·4-90·4). Sensitivity was 93·6% (90·0-97·3) and specificity 59·9% (54·1-65·7) in HIV-positive women. Cycle threshold values from channels detecting HPV type 16, HPV types 18 or 45 (or both), and HPV types 31, 33, 35, 52, or 58 (or more than one of these types) were informative to predict cervical intraepithelial neoplasia grade 2 or greater. Shifting cycle threshold cutoffs on these three channels allowing sensitivity to decline to 75-85%, led to specificities of 91·3-95·3% in HIV-negative women and 77·0-85·8% in HIV-positive women.

INTERPRETATION

More stringent cycle threshold cutoffs on selected channels in Xpert HPV improve specificity with only modest losses in sensitivity, making this assay an optimal choice for HPV-based screen and treat in settings with a high prevalence of HIV. These modifications can be made from standard output with no need for new engineering. Decision making about performance characteristics of HPV testing can be shifted to programme implementers and cutoffs selected according to resource availability and community preferences.

FUNDING

Supported by the National Cancer Institute UH2/3 CA189908.

From potential to practice: how accelerating access to HPV tests and screen and treat programmes can help eliminate cervical cancer

Human papillomavirus (HPV) vaccination campaigns to prevent cervical cancer are being considered and implemented in countries around the world. While vaccination will protect future generations, it will not help the millions of women currently infected, leading to an estimated 311 000 deaths per year globally. This paper examines a selection of strategies that when applied to both existing and new technologies, could accelerate access to HPV testing. Authors from the US Agency for International Development, the National Institutes of Health, and the Bridge to Health Medical and Dental, a non-governmental organisation, joined forces to propose a scalable and country-directed solution for preventing cervical cancer using an end-to-end approach. Collectively, the authors offer seven evidence-based strategies, that when used alone or in combination have the ability to reduce HPV-caused cervical cancer deaths and disability. These strategies include (1) consistent HPV test intervals to decrease HPV DNA test costs; (2) exploring market shaping opportunities; (3) employing iterative user research methodologies like human-centred design; (4) target product profiles for new HPV tests; (5) encouraging innovation around cervical cancer screen and treat programmes; (6) developing national cancer control plans; and (7) integrating cervical cancer screen and treat services into existing infrastructure. By using the strategies outlined here, in combination with HPV vaccination campaigns, national governments will be able to scale and expand cervical cancer screening programmes and provide evidence-based treatment programmes for HPV-infected women.

Cost-effectiveness studies of HPV self-sampling: A systematic review

HPV self-sampling (HPV-SS) can increase cervical cancer screening participation by addressing barriers in high- and low- and middle-income settings. Successful implementation of HPV-SS programs will depend on understanding potential costs and health effects. Our objectives were to summarize the methods and results of published HPV-SS cost and cost-effectiveness studies, present implications of these results for HPV-SS program implementation, and identify knowledge gaps. We followed the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guidelines. One reviewer searched online databases for articles published through June 12, 2019, identified eligible studies, and extracted data; a second reviewer checked extracted data for accuracy. Eligible studies used an economic model to compare HPV-SS outreach strategies to standard-of-care tests. Of 16 eligible studies, 14 reported HPV-SS could be a cost-effective strategy. Studies differed in model type, HPV-SS delivery methods, triage strategies for positive results, and target populations. Most (9/16) modeled HPV-SS in European screening programs, 6/16 targeted women who were underscreened for cervical cancer, and 5/16 modeled HPV-SS in low- and middle-income countries. The most commonly identified driver of HPV-SS cost-effectiveness was the level of increase in cervical cancer screening attendance. Lower HPV-SS material and testing costs, higher sensitivity to detect cervical precancer, and longer duration of underscreening among HPV-SS users were also associated with increased cost-effectiveness. Future HPV-SS models in high-income settings should explore the effect of widespread vaccination and new triage strategies such as partial HPV genotyping. Knowledge gaps remain about the cost-effectiveness of HPV-SS in low- and middle-income settings.

Comparison of the Accuracy of Papanicolaou Test Cytology, Visual Inspection With Acetic Acid, and Visual Inspection With Lugol Iodine in Screening for Cervical Neoplasia in Southeast Nigeria

Purpose

This study aimed to compare the accuracy of Papanicolaou test cytology, visual inspection with 5% acetic acid (VIA), and visual inspection with Lugol iodine (VILI) in the detection of premalignant and malignant lesions of the cervix.

Materials and Methods

This was a cross-sectional comparative study of 200 consenting participants at the Federal Teaching Hospital, Abakaliki over a 6-month period. All the participants had Papanicolaou test cytology. Subsequently, they were classified into two groups of 100 each through systematic random sampling: group 1 had VIA and group 2 had VILI. Thereafter, all the participants had cervical punch biopsy at the 6 and 12 o’clock cervical positions. Cervical punch biopsy was also done on the suspicious lesions of the cervix irrespective of their positions. The tests of validity of the three methods were calculated using the histology of the biopsy specimen as the gold standard. P value ≤ .05 was considered to be statistically significant.

Results

Among the VIA group, 19 (19%) had cervical epithelial abnormalities on Papanicolaou test cytology, and VIA was positive in 14 (14%). Histology results showed cervical neoplasia in 15 (15%) of the participants. Among the VILI group, 15 (15%) had cervical epithelial abnormalities on Papanicolaou test cytology, and VILI was positive in 19 (19%). Histology results showed cervical neoplasia in 15 (15%) of the participants. There was no significant difference in overall accuracy of Papanicolaou test cytology, VIA, and VILI. The overall accuracy of the Papanicolaou test cytology plus VIA was significantly more than Papanicolaou test cytology alone.

Conclusion

VIA or VILI can be used as a stand-alone cervical cancer screening test when compared with Papanicolaou test cytology, particularly in resource-limited settings. VIA can also complement Papanicolaou test cytology.

Performance of vaginal self-sampling for human papillomavirus testing among women living with HIV in Botswana

Background:

In Botswana, where HIV prevalence remains high, cervical cancer is the leading cause of cancer deaths in women. Multiple organizations recommend high-risk human papillomavirus (hr-HPV) testing as a screening tool, however, high coverage may not be feasible with provider-collected samples. We conducted the first assessment of self- versus provider-collected samples for hr-HPV testing in HIV-positive women in Botswana and report prevalence of hr-HPV and histological outcomes.

Methods:

We recruited HIV-positive women ≥25 years attending an HIV clinic in Gaborone. Self- and provider-collected samples from participants were tested for hr-HPV using Cepheid GeneXpert. Women testing positive for any hr-HPV returned for colposcopy. We used unweighted κ statistics to determine hr-HPV agreement.

Results:

Thirty-one (30%) of 103 women tested positive for any hr-HPV. The most common genotypes were HPV 31/33/35/52/58. Overall agreement between self- and provider-collected samples for any hr-HPV was 92% with a κ of 0.80. Ten of the 30 hr-HPV positive women attending colposcopy had CIN 2+ (33%).

Conclusions:

In this HIV-positive population, hr-HPV prevalence was 30%, with excellent agreement between self and provider samples. Self-sampling may play an important role in screening programs in high HIV burden settings with limited resources like Botswana.

Assessment of the scale-up of cervical cancer screening in Abidjan stratified by HIV status

OBJECTIVE

To report the successes and challenges of scaling up a population-based cervical cancer (CC) screening program from HIV clinics to various healthcare facilities in Abidjan, Côte d'Ivoire.

METHOD

A retrospective analysis of characteristics, outcomes, and follow-up of women attending an initial CC screening visit in Abidjan between January 2010 and December 2014. Data were collected via forms that were systematically completed during CC screening visits. Data from the 2014 population census were used to estimate screening coverage.

RESULTS

Among 16 169 women attending an initial CC screening, 1616 (10.0%) had a positive VIA test. Among 848 women eligible for immediate cryotherapy, 618 (72.9%) underwent the "see-and-treat" approach. The 1-year follow-up rate after cryotherapy was 23.1% (143/618), and was higher among women with HIV (111/362, 30.7%) than among other women (32/256, 12.5%) (P=0.001). The estimated coverage of CC screening in Abidjan was 1.2% (95% confidence interval, 0.6-3.1).

CONCLUSION

Despite successful expansion of CC screening from HIV clinics to other facilities, the estimated screening coverage of the targeted population remained low. Follow-up of positively screened and treated women is a major challenge, especially outside HIV clinics, and would benefit from an innovative information system proving unique identification and tracking systems.

Cervical cancer screening decentralized policy adaptation: an African rural-context-specific systematic literature review

Background: Worldwide, nearly 570,000 women are diagnosed with cervical cancer each year, with 85% of new cases in low- and middle-income countries. The African continent is home to 35 of 40 countries with the highest cervical cancer mortality rates. In 2014, a partnership involving a rural region of Senegal, West Africa, was facing cervical cancer screening service sustainability barriers and began adapting regional-level policy to address implementation challenges.

Objective: This manuscript reports the findings of a systematic literature review describing the implementation of decentralized cervical cancer prevention services in Africa, relevant in context to the Senegal partnership. We report barriers and policy-relevant recommendations through Levesque’s Patient-Centered Access to Healthcare Framework and discuss the impact of this information on the partnership’s approach to shaping Senegal’s regional cervical cancer screening policy.

Methods: The systematic review search strategy comprised two complementary sub-searches. We conducted an initial search identifying 4272 articles, then applied inclusion criteria, and ultimately 19 studies were included. Data abstraction focused on implementation barriers categorized with the Levesque framework and by policy relevance.

Results: Our findings identified specific demand-side (clients and community) and supply-side (health service-level) barriers to implementation of cervical cancer screening services. We identify the most commonly reported demand- and supply-side barriers and summarize salient policy recommendations discussed within the reviewed literature.

Conclusions: Overall, there is a paucity of published literature regarding barriers to and best practices in implementation of cervical cancer screening services in rural Africa. Many articles in this literature review did describe findings with notable policy implications. The Senegal partnership has consulted this literature when faced with various similar barriers and has developed two principal initiatives to address contextual challenges. Other initiatives implementing cervical cancer visual screening services in decentralized areas may find this contextual reporting of a literature review helpful as a construct for identifying evidence for the purpose of guiding ongoing health service policy adaptation.

HPV self-testing for primary cervical cancer screening in Madagascar: VIA/VILI triage compliance in HPV-positive women

Objective

To assess triage compliance and the effect of the time from screening to triage on follow-up among HPV-positive women.

Methods

We recruited 1232 women in a screening campaign in Madagascar from February to October 2015. In the first period (February–May), HPV tests were performed remotely using the cobas test. In the second period (May–October), testing was performed on-site using the Xpert HPV assay. HPV-positive women were invited for triage with visual inspection with acetic acid (VIA) and Lugol’s iodine (VILI). Systematic biopsy and endocervical brushing were performed on all HPV-positive women for quality control. Three groups were defined according to time from HPV testing to triage invitation for HPV-positive women—Group I: delayed (> 3 months), Group II: prompt (24–48 hours), and Group III: immediate (< 24 hours).

Results

A total 1232 self-sampled HPV tests were performed in the study period (496 in Group I, 512 in Group II, and 224 in Group III). Participants’ mean age was 43.2 ± 9.3 years. Mean time from screening to VIA/VILI testing was 103.5 ± 43.6 days. Overall HPV prevalence was 28.0%. HPV prevalence was 27.2% in Group I (cobas test), 29.2% in Group 2 (Xpert test), and 26,7% in Group III (Xpert test). The VIA/VILI compliance rate was 77.8% for Group I, 82.7% for Group II, and 95.0% for Group III. Of women undergoing VIA/VILI, 56.3% in Group I and 43.5% in Groups II/III had positive results. Prevalence of cervical intraepithelial neoplasia grade 2 or worse among HPV-positive women was 9.8% for Group I and 6.8% for Groups II/III. Non-adherence was higher among rural women, uneducated women, and women in Group I.

Conclusion

HPV-positive women with immediate VIA/VILI triage invitation had the best triage compliance. A single-day test and triage strategy is preferred for low-resource settings.

Impact of operational factors on HPV positivity rates in an HPV-based screening study in Colombia

OBJECTIVE

To assess the effect of operational factors on the positivity rates of three HPV assays.

METHODS

Within the cross-sectional ESTAMPA study, women aged 30-64 years were recruited at healthcare centers from Soacha, Colombia, during 2012-2015. Cervical samples were collected for cotesting with Hybrid Capture 2 (HC2; Qiagen, Gaithersburg, MD, USA), and either Aptima (Hologic, Marlborough, MA, USA) or Cobas 4800 (Roche Diagnostics, Indianapolis, IN, USA). The effect of operational factors on assay performance was assessed using adjusted positivity rates obtained from logistic regression models.

RESULTS

There were 4168 women included. For samples collected in assay-specific medium, positivity rate differences were associated with the expertise of the nurse collecting the sample (P=0.014 HC2; P=0.091 Aptima) and if sample collection occurred after an initial cytology (P=0.025 HC2; P=0.033 Aptima). If PreservCyt medium (Hologic) was used, HC2 positivity differences were observed depending on the time between sample collection and processing (P=0.026) and on the laboratory technician processing the samples (P=0.003). No differences were observed for PreservCyt samples processed with Aptima or Cobas.

CONCLUSION

Nurse expertise, collection of previous cytology, processing time, and laboratory technician could influence HPV assay performance. Suitable quality assurance protocols for HPV-based screening programs are required. ClinicalTrials.gov: NCT01881659.

Implementation of Multicolor Melt Curve Analysis for High-Risk Human Papilloma Virus Detection in Low- and Middle-Income Countries: A Pilot Study for Expanded Cervical Cancer Screening in Honduras

PURPOSE

Cervical cancer is a leading cause of cancer-related mortality in low- and middle-income countries (LMICs) and screening in LMICs is extremely limited. We aimed to implement on-site high-risk human papillomavirus (hrHPV) DNA testing in cohorts of women from an urban factory and from a rural village.

METHODS

A total of 802 women were recruited for this study in partnership with La Liga Contra el Cancer through the establishment of women's health resource fairs at two locations in Honduras: a textile factory (n = 401) in the city of San Pedro Sula and the rural village of El Rosario (n = 401) in Yoro. Participants received a routine cervical examination during which three sterile cytobrushes were used to collect cervical samples for testing. hrHPV genotyping was performed using a hrHPV genotyping assay and a real-time polymerase chain reaction instrument.

RESULTS

hrHPV status across all participants at both sites was 13% hrHPV positive and 67% hrHPV negative. When hrHPV status was compared across all three testing sites, hrHPV-positive rates were approximately equal among the factory (13%), village (12%), and confirmatory testing at Dartmouth-Hitchcock Medical Center (Lebanon, NH; 14%). hrHPV genotype was compared across sites, with HPV16 showing the highest infection rate (15%), followed by HPV59 (12%), and HPV68 (11%). There was a low prevalence of HPV18 observed in both populations compared with the hrHPV-positive population in the United States.

CONCLUSION

In collaboration with oncologists and pathologists from La Liga Contra el Cancer, we were able to provide a continuum of care once health-fair testing was performed. We established a method and implementation plan for hrHPV testing that is sustainable in LMICs.

Secondary prevention of cervical cancer

Cervical cancer affects women in their reproductive ages. Screening is an important secondary prevention strategy. The long process of carcinogenic transformation from human papillomavirus (HPV) infection to invasive cancer provides ample opportunities to detect the disease at a stage when treatment is highly effective. Suitable screening tests are cytology, visual inspection after acetic acid application and HPV detection tests. Evidence of effectiveness of the tests to reduce cervical cancer mortality and the cost-effectiveness of screening programs have been demonstrated. Cervical intraepithelial neoplasia grade 2 and grade 3 are the high-grade cervical cancer precursors and need to be treated. Treatment is safe and effective with ablative or excisional techniques. The World Health Organization recommends screening women at least once in a lifetime between 30 and 49 years of age and ensuring effective treatment of the detected abnormalities. Combination of HPV vaccination and population-based screening will be instrumental in eliminating cervical cancer.

Community-Based Screening for Cervical Cancer Using Visual Inspection With Acetic Acid: Results and Lessons Learned From a Pilot Study in Vietnam

CONTEXT

Vietnam still applies the opportunistic cytology-based screening model, which failed to have an impact on the increasing burden of cervical cancer in Vietnam.

OBJECTIVES

To pilot a community-based screening model for cervical cancer using visual inspection with acetic acid (VIA) in Vietnam by training midwife and assistant physician working at grassroots level of health care system.

DESIGN

The study employed a pre-experimental design.

SETTING

Cases from 2 provinces of Vietnam.

PARTICIPANTS

The study trained 36 assistant physicians/midwives working at commune health centers to do VIA screening for cervical cancer and provided screening services for 1945 women 30 to 65 years of age.

INTERVENTION

The pilot intervention had 2 aims: train health care workers to do VIA screening and assess the quality of screening services provided by the trained staffs by examining the diagnostics value of VIA.

RESULTS

All selected health care workers were able to perform VIA screening method after training. Their VIA services had high diagnostic value: positive predicted value of 11.5% and negative predicted value of 99%; for the detection of cervical intraepithelial neoplasia (CIN) 2, the sensitivity of VIA is 100%, specificity of 67.0%, positive predicted value of 5.7%, and negative predicted value of 100%; for the detection of CIN 3, the sensitivity of VIA is 100%, specificity of 66.5%, positive predicted value of 3.8%, and negative predicted value of 100%. The diagnostic value of VIA is comparable with Papanicolaou test but requires far fewer resources and suitable with community-based setting.

CONCLUSION

Local midwives and assistant physicians who currently work at commune health centers and district health centers can be trained to do VIA efficiently. Regarding to implications for policy and practice, VIA can offer significant advantages over Papanicolaou test in low-resource settings like Vietnam, particularly in terms of increased screening coverage, improved follow-up care, and overall program quality.

Cost-effectiveness of cervical cancer screening and preventative cryotherapy at an HIV treatment clinic in Kenya

Objective

This study evaluated the potential cost-effectiveness of cervical cancer screening in HIV treatment clinics in Nairobi, Kenya.

Methods

A Markov model was used to project health outcomes and costs of cervical cancer screening and cryotherapy at an HIV clinic in Kenya using cryotherapy without screening, visual inspection with acetic acid (VIA), Papanicolaou smear (Pap), and testing for human papillomavirus (HPV). Direct and indirect medical and non-medical costs were examined from societal and clinic perspectives.

Results

Costs of cryotherapy, VIA, Pap, and HPV for women with CD4 200–500 cells/mL were $99, $196, $219, and $223 from a societal perspective and $19, $94, $124, and $113 from a clinic perspective, with 17.3, 17.1, 17.1, and 17.1 years of life expectancy, respectively. Women at higher CD4 counts (>500 cells/mL) given cryotherapy VIA, Pap, and HPV resulted in better life expectancies (19.9+ years) and lower cost (societal: $49, $99, $115, and $102; clinic: $13, $51, $71, and $56). VIA was less expensive than HPV unless HPV screening could be reduced to a single visit.

Conclusions

Preventative cryotherapy was the least expensive strategy and resulted in highest projected life expectancy, while VIA was most cost-effective unless HPV could be reduced to a single visit.

Management algorithms for cervical cancer screening and precancer treatment for resource-limited settings

Management algorithms for screen-positive women in cervical cancer prevention programs have undergone substantial changes in recent years. The WHO strongly recommends human papillomavirus (HPV) testing for primary screening, if affordable, or if not, then visual inspection with acetic acid (VIA), and promotes treatment directly following screening through the screen-and-treat approach (one or two clinic visits). While VIA-positive women can be offered immediate ablative treatment based on certain eligibility criteria, HPV-positive women need to undergo subsequent VIA to determine their eligibility. Simpler ablative methods of treatment such as cryotherapy and thermal coagulation have been demonstrated to be effective and to have excellent safety profiles, and these have become integral parts of new management algorithms. The challenges faced by low-resource countries are many and include, from the management perspective, identifying an affordable point-of-care HPV detection test, minimizing over-treatment, and installing an effective information system to ensure high compliance to treatment and follow-up.

Scale-Up of an Human Papillomavirus Testing Implementation Program in El Salvador

Scale-up of a low-cost human papillomavirus testing implementation project in El Salvador showed that the follow-up completion rate with screen-and-treat management was twice that with colposcopy management.

Objective

The Cervical Cancer Prevention in El Salvador is a demonstration project to introduce a lower-cost human papillomavirus (HPV)-DNA test into a public sector project. Started in October 2012, The Cervical Cancer Prevention in El Salvador consists of 3 phases and will ultimately screen 30,000 women. Results of phase 2 of the project are presented. The objective of this project was to compare colposcopy and noncolposcopy-based management for HPV-positive women.

Material and Methods

In phase 2, a total of 8,050 women, aged 30 to 49 years, were screened; 6,761 provided both self- and provider-collected specimens and 1,289 provided only provider-testing specimens. HPV results from self-collected specimens were not used in clinical management decisions. Women with provider-collected HPV-positive results were treated based on the strategy assigned to their community; the strategy was colposcopy management (CM) or screen-and-treat (ST) management if they were cryotherapy eligible or colposcopy if not eligible. Outcomes were assessed 6 months after screening.

Results

Overall, 489 (12.3%) of 3,963 women receiving CM and 465 (11.4%) of 4,087 women receiving ST tested HPV positive. In the CM cohort, 216 (44.2%) of 489 completed their intervention (203 treated, 11 diagnosed negative, 2 pregnant). In the ST cohort, 411 (88.4%) of 465 completed their intervention (407 treated, 2 diagnosed negative, 1 pregnant). Overall agreement between HPV test results from self-collected and provider-collected specimens was 93.7%, with a κ value of 0.70 (95% CI = 0.68–0.73).

Conclusions

Human papillomavirus testing with ST management resulted in an approximately twice completion rate compared with CM management. Agreement between self- and provider-based sampling was good and might be used to extend screening to women in areas that are more difficult to reach.

Interventions to close the divide for women with breast and cervical cancer between low-income and middle-income countries and high-income countries

Breast and cervical cancers are the commonest cancers diagnosed in women living in low-income and middle-income countries (LMICs), where opportunities for prevention, early detection, or both, are few. Yet several cost-effective interventions could be used to reduce the burden of these two cancers in resource-limited environments. Population- wide vaccination against human papillomavirus (HPV) linked to cervical screening, at least once, for adult women has the potential to reduce the incidence of cervical cancer substantially. Strategies such as visual inspection with acetic acid and testing for oncogenic HPV types could make prevention of cervical cancer programmatically feasible. These two cancers need not be viewed as inevitably fatal, and can be cured, particularly if detected and treated at an early stage. Investing in the health of girls and women is an investment in the development of nations and their futures. Here we explore ways to lessen the divide between LMICs and high-income countries for breast and cervical cancers.

Implementing visual cervical cancer screening in Senegal: a cross-sectional study of risk factors and prevalence highlighting service utilization barriers

BACKGROUND

Senegal ranks 15th in the world in incidence of cervical cancer, the number one cause of cancer mortality among women in this country. The estimated participation rate for cervical cancer screening throughout Senegal is very low (6.9% of women 18-69 years old), especially in rural areas and among older age groups (only 1.9% of women above the age of 40 years). There are no reliable estimates of the prevalence of cervical dysplasia or risk factors for cervical dysplasia specific to rural Senegal. The goals of this study were to estimate the prevalence of cervical dysplasia in a rural region using visual inspection of the cervix with acetic acid (VIA) and to assess risk factors for cervical cancer control.

PATIENTS AND METHODS

We conducted a cross-sectional study in which we randomly selected 38 villages across the Kédougou region using a three-stage clustering process. Between October 2013 and March 2014, we collected VIA screening results for women aged 30-50 years and cervical cancer risk factors linked to the screening result.

RESULTS

We screened 509 women; 5.6% of the estimated target population (9,041) in the region. The point prevalence of cervical dysplasia (positive VIA test) was 2.10% (95% confidence interval [CI]: 0.99-3.21). Moreover, 287 women completed the cervical cancer risk factor survey (56.4% response rate) and only 38% stated awareness of cervical cancer; 75.9% of the screened women were less than 40 years of age.

CONCLUSION

The overall prevalence of dysplasia in this sample was lower than anticipated. Despite both overall awareness and screening uptake being less than expected, our study highlights the need to address challenges in future prevalence estimates. Principally, we identified that the highest-risk women are the ones least likely to seek screening services, thus illustrating a need to fully understand demand-side barriers to accessing health services in this population. Targeted efforts to educate and motivate older women to seek screenings are needed to sustain an effective cervical cancer screening program.

Feasibility of thermocoagulation in a screen-and-treat approach for the treatment of cervical precancerous lesions in sub-Saharan Africa

BACKGROUND

The use of thermocoagulation for the treatment of cervical precancerous lesions has recently generated a great deal of interest. Our aim was to determine the feasibility of this outpatient procedure in the context of a cervical cancer (CC) screen-and-treat campaign in sub-Saharan Africa.

METHODS

Between July and December 2015, women living in the area of Dschang (Cameroon) aged between 30 and 49 years, were enrolled in a CC screening study. HPV self-sampling was performed as a primary screening test and women who were either "HPV 16/18/45-positive" or "positive to other HPV types and to VIA" were considered screen-positive, thus requiring further management. The primary outcome was the percentage of screen-positive patients who met the criteria to undergo thermocoagulation. The secondary outcome was the assessment of the procedure's side effects immediately after treatment and at the 1-month follow-up visit.

RESULTS

A total of 1012 women were recruited in the study period. Among 121 screen-positive women, 110 of them (90.9%) were eligible to be treated with thermocoagulation. No patients discontinued treatment because of pain or other side effects. The mean ± SD (Standard Deviation) score measured on the 10-point Visual Analogue Scale (VAS) was 3.0 ± 1.6. Women having less than 2 children were more likely to report a higher pain score than those with more than two (4.2 ± 2.0 versus 2.9 ± 1.5, respectively; p value = 0.016). A total of 109/110 (99.1%) patients came to the 1-month follow-up visit. Vaginal discharge was reported in 108/109 (99.1%) patients throughout the month following treatment. Three patients (2.8%) developed vaginal infection requiring local antibiotics. No hospitalizations were required.

CONCLUSION

The majority of screen-positive women met the criteria and could be treated by thermocoagulation. The procedure was associated to minor side effects and is overall feasible in the context of a CC screen-and-treat campaign in sub-Saharan Africa.

TRIAL REGISTRATION

The trial was retrospectively registered on November 11, 2015 with the identifier: ISRCTN99459678 .

Introducing a High-Risk HPV DNA Test Into a Public Sector Screening Program in El Salvador

OBJECTIVE

In a primary human papillomavirus (HPV) screening program, we compared the 6-month follow-up among colposcopy and noncolposcopy-based management strategies for screen-positive women.

MATERIALS AND METHODS

Women aged 30 to 49 years were screened with HPV DNA tests using both self-collection and provider collection of samples. Women testing positive received either (1) colposcopy management (CM) consisting of colposcopy and management per local guidelines or (2) screen-and-treat (ST) management using visual inspection with acetic acid to determine cryotherapy eligibility, with eligible women undergoing immediate cryotherapy. One thousand women were recruited in each cohort. Of these, 368 (18.4%) of 2000 women were recruited using a more intensive outreach strategy. Demographics, HPV positivity, and treatment compliance were compared across recruitment and management strategies.

RESULTS

More women in the ST cohort received treatment within 6 months compared with those in the CM cohort (117/119 [98.3%] vs 64/93 [68.8%]; p < .001). Women recruited through more intensive outreach were more likely to be HPV positive, lived in urban areas, were more educated, and had higher numbers of lifetime sexual partners and fewer children.

CONCLUSIONS

Women in the CM arm were less likely to complete care than women in the ST arm. Targeted outreach to underscreened women successfully identified women with higher prevalence of HPV and possibly higher disease burden.

A Markov Decision Process Model for Cervical Cancer Screening Policies in Colombia

Cervical cancer is the second most common cancer in women around the world, and the human papillomavirus (HPV) is universally known as the necessary agent for developing this disease. Through early detection of abnormal cells and HPV virus types, cervical cancer incidents can be reduced and disease progression prevented. We propose a finite-horizon Markov decision process model to determine the optimal screening policies for cervical cancer prevention. The optimal decision is given in terms of when and what type of screening test to be performed on a patient based on her current diagnosis, age, HPV contraction risk, and screening test results. The cost function considers the tradeoff between the cost of prevention and treatment procedures and the risk of taking no action while taking into account a cost assigned to loss of life quality in each state. We apply the model to data collected from a representative sample of 1141 affiliates at a health care provider located in Bogotá, Colombia. To track the disease incidence more effectively and avoid higher cancer rates and future costs, the optimal policies recommend more frequent colposcopies and Pap tests for women with riskier profiles.

Cost-Effectiveness of Primary HPV Testing, Cytology and Co-testing as Cervical Cancer Screening for Women Above Age 30 Years

BACKGROUND

Cervical cancer screening guidelines for women aged ≥30 years allow for co-testing or primary cytology testing. Our objective was to determine the test characteristics and costs associated with Cytology, HPV and Co-testing screening strategies.

MAIN METHODS

Retrospective cohort study of women undergoing cervical cancer screening with both cytology and HPV (Hybrid Capture 2) testing from 2004 to 2010 in an integrated health system. The electronic health record was used to identify women aged ≥30 years who had co-testing. Unsatisfactory or unavailable test results and incorrectly ordered tests were excluded. The main outcome was biopsy-proven cervical intraepithelial neoplasia grade 3 or higher (CIN3+).

KEY RESULTS

The final cohort consisted of 99,549 women. Subjects were mostly white (78.4 %), married (70.7 %), never smokers (61.3 %) and with private insurance (86.1 %). Overall, 5121 (5.1 %) tested positive for HPV and 6115 (6.1 %) had cytology ≥ ASCUS; 1681 had both and underwent colposcopy and 310 (0.3 %) had CIN3+. Sensitivity for CIN3+ was 91.9 % for Primary Cytology, 99.4 % for Co-testing, and 94.8 % for Primary HPV; specificity was 97.3 % for Co-testing and Primary Cytology and 97.9 % for Primary HPV. Over a 3-year screening interval, Primary HPV detected more cases of CIN3+ and was less expensive than Primary Cytology. Co-testing detected 14 more cases of CIN3+ than Primary HPV, but required an additional 100,277 cytology tests and 566 colposcopies at an added cost of $2.38 million, or $170,096 per additional case detected.

CONCLUSIONS

Primary HPV was more effective and less expensive than Primary Cytology. Primary HPV screening appears to represent a cost-effective alternative to Co-testing.

Options for Handling Missing Data in the Health Utilities Index Mark 3

Background. The Health Utilities Index Mark 3 (HUI3) is a tool composed of 41 questions, covering 8 attributes: vision, hearing, speech, ambulation, dexterity, emotion, cognition, and pain. Responses to these questions can define more than 972,000 health situations. This tool allows respondents to answer “Don’t Know,” for which there is no scoring instruction, to any given question. This situation creates a break in the scoring algorithm and leads to considerable amounts of missing data. The goal of this study is to develop strategies to deal with HUI3 scores for participants who have missing data. Methods. The authors used data from 248 individuals enrolled in the Cataract Management Trial, focusing on the HUI3 vision and ambulation attributes, which had 19% and 10% of attribute levels missing, respectively. Inspection and deduction were used to fill in values independent of the value of the missing data, then alternative analytic techniques were compared, including mean substitution, model scoring, hot deck, multiple imputation, and regression imputation. Results. Inspection and logical deduction reduced the percentage of missing information in the HUI3 by 49% to 87%. A comparison of analytic techniques used for the remaining HUI3 vision data missing demonstrated the value of building models based on internal response patterns and that simple analytic techniques fare as well as more complicated ones when the number of missing cases is small. Conclusion .Analyzing the pattern of responses in cases where the attribute level score is missing reduces the amount of missing data and can simplify the analytic process for the remaining missing data.

The Cost-Effectiveness of Screening Programs Using Single and Multiple Birth Cohort Simulations: A Comparison Using a Model of Cervical Cancer

Despite early recognition of the theoretical advantages of simulations that include different population subgroups/ strata and different birth cohorts, manymodeling-based economic evaluations of cervical screening have been based on unrealistic single birth cohort simulations. The authors examined the effect of amultiple birth cohort simulation on the incremental cost-effectiveness estimates of cervical screening programs, compared to a conventional single cohort simulation. The choice of hypothetical cohort that starts the simulation had a major impact on the cost-effectiveness estimates: Compared with a single birth cohort simulation, the incremental cost-effectiveness of a shift from biennial to triennial screening was 30% higher when using the multiple cohort simulation. Multiple cohort simulations using the different age structures of 4 countries had little impact on the costeffectiveness ratios (variation <5%). Future modeling-based evaluations of screening policies should better reflect the age range of the population that is targeted by carefully specifying the nature of the starting cohort(s).

Prevalence, Predictors, and Same Day Treatment of Positive VIA Enhanced by Digital Cervicography and Histopathology Results in a Cervical Cancer Prevention Program in Cameroon

Background

In 2007, the Cameroon Baptist Convention Health Services (CBCHS) implemented a screen-and-treat cervical cancer prevention program using visual inspection with acetic acid enhanced by digital cervicography (VIA-DC).

Methods

We retrospectively analyzed 46,048 medical records of women who received care through the CBCHS Women’s Health Program from 2007 through 2014 to determine the prevalence and predictors of positive VIA-DC, rates of same day treatment, and cohort prevalence of invasive cervical cancer (ICC).

Results

Of the 44,979 women who were screened for cervical cancer, 9.0% were VIA-DC-positive, 66.8% were VIA-DC-negative, 22.0% were VIA-DC-inadequate (normal ectocervix, but portions of the transformation zone were obscured), and 2.2% were VIA-DC-uncertain (cervical abnormalities confounding VIA-DC interpretation). Risk factors significantly associated with VIA-DC-positive screen were HIV-positivity, young age at sexual debut, higher lifetime number of sexual partners, low education status and higher gravidity. In 2014, 31.1% of women eligible for cryotherapy underwent same day treatment. Among the 32,788 women screened from 2007 through 2013, 201 cases of ICC were identified corresponding to a cohort prevalence of 613 per 100,000.

Conclusions

High rate of VIA-DC-positive screens suggests a significant burden of potential cervical cancer cases and highlights the need for expansion of cervical cancer screening and prevention throughout the 10 regions of Cameroon. VIA-DC-inadequate rates were also high, especially in older women, and additional screening methods are needed to confirm whether these results are truly negative. In comparison to similar screening programs in sub-Saharan Africa there was low utilization of same day cryotherapy treatment. Further studies are required to characterize possible program specific barriers to treatment, for example cultural demands, health system challenges and cost of procedure. The prevalence of ICC among women who presented for screening was high and requires further investigation.

Cost-effectiveness analysis of human papillomavirus vaccination in South Africa accounting for human immunodeficiency virus prevalence

Background

This study aims at evaluating the cost-effectiveness of a 2-dose schedule human papillomavirus (HPV) vaccination programme of HPV and human immunodeficiency virus (HIV) naïve 12-year-old girls, in addition to cervical cancer (CC) screening alone, in South Africa. The study aims to account for both the impact of the vaccine among girls who are HIV-positive (HIV+) as well as HIV-negative (HIV-) population.

Methods

A previously published Markov cohort model was adapted to assess the impact and cost-effectiveness of a HPV vaccination programme in girls aged 12 years (N = 527 900) using the AS04-adjuvanted HPV-16/18 vaccine from a public payer perspective. Two subpopulations were considered: HIV- and HIV+ women. Each population followed the HPV natural history with different transition probabilities. Model input data were obtained from the literature, local databases and Delphi panel. Costs and outcomes were discounted at 5 %. Extensive sensitivity analyses were conducted to assess the robustness of the evaluation.

Results

Implementation of the AS04-adjuvanted HPV-16/18 vaccine in combination with current cytological screening in South African girls could prevent up to 8 869 CC cases and 5 436 CC deaths over the lifetime of a single cohort. Without discounting, this HPV vaccine is dominant over screening alone; with discounting, the incremental cost-effectiveness ratio is ZAR 81 978 (South African Rand) per quality-adjusted life years (QALY) gained. HPV vaccination can be considered cost-effective based on World Health Organization (WHO) recommended threshold (3 x gross domestic product/capita = ZAR 200 293). In a scenario with a hypothetical targeted vaccination in a HIV+ subpopulation alone, the modelled outcomes suggest that HPV vaccination is still cost-effective, although the incremental cost-effectiveness ratio increases to ZAR 102 479. Results were sensitive to discount rate, vaccine efficacy, HIV incidence and mortality rates, and HPV-related disease transition probabilities.

Conclusions

The AS04-adjuvanted HPV-16/18 vaccine can be considered cost-effective in a South African context although the cost-effectiveness is expected to be lower in the HIV+ subpopulation than in the overall female population. With improved access to HIV treatment, the HIV mortality and incidence rates are likely to be reduced, which could improve cost-effectiveness of the vaccination programme in South Africa.

Electronic supplementary material

The online version of this article (doi:10.1186/s12879-015-1295-z) contains supplementary material, which is available to authorized users.

Cervical cancer screening in developing countries at a crossroad: Emerging technologies and policy choices

Cervical cancer (CC) represents the fourth most common malignancy affecting women all over the world and is the second most common in developing areas. In these areas, the burden from disease remains important because of the difficulty in implementing cytology-based screening programmes. The main obstacles inherent to these countries are poverty and a lack of healthcare infrastructures and trained practitioners. With the availability of new technologies, researchers have attempted to find new strategies that are adapted to low- and middle-income countries (LMIC) to promote early diagnosis of cervical pathology. Current evidence suggests that human papillomavirus (HPV) testing is more effective than cytology for CC screening. Therefore, highly sensitive tests have now been developed for primary screening. Rapid molecular methods for detecting HPV DNA have only recently been commercially available. This constitutes a milestone in CC screening in low-resource settings because it may help overcome the great majority of obstacles inherent to previous screening programmes. Despite several advantages, HPV-based screening has a low positive predictive value for CC, so that HPV-positive women need to be triaged with further testing to determine optimal management. Visual inspection tests, cytology and novel biomarkers are some options. In this review, we provide an overview of current and emerging screening approaches for CC. In particular, we discuss the challenge of implementing an efficient cervical screening adapted to LMIC and the opportunity to introduce primary HPV-based screening with the availability of point-of-care (POC) HPV testing. The most adapted screening strategy to LMIC is still a work in progress, but we have reasons to believe that POC HPV testing makes part of the future strategies in association with a triage test that still needs to be defined.