Impact of patient adherence and test performance on the cost-effectiveness of cervical cancer screening in developing countries: the case of Honduras

A Systematic Review of Health Economic Evaluations and Budget Impact Analyses to Inform Healthcare Decision-Making in Central America

BACKGROUND

Little is known about the quality, quantity and disease areas analysed by health economic research that inform healthcare decision-making in Central America. This study aimed to review the existing health economic evaluations (HEEs) and budget impact analyses (BIAs) evidence in Central America based on scope and reporting quality.

METHODS

HEEs and BIAs published from 2000 to April 2021 were searched in five electronic databases: PubMed, Embase, LILACS (Latin American and Caribbean Health Science Literature), EconLIT and OVID Global Health. Two reviewers assessed titles, abstracts and full texts of studies for eligibility. The quality appraisal for the reporting was based on La Torre and colleagues' version of the Drummond checklist and the ISPOR good practices for BIA. For each country, we correlated the number of studies by disease area with their respective burden of disease to identify under-researched health areas.

RESULTS

102 publications were eligible for this review. Ninety-four publications reported a HEE, six publications reported a BIA, and two studies reported both a HEE and a BIA. Costa Rica had the highest number of publications (n = 28, 27.5%), followed by Guatemala (n = 25, 24.5%). Cancer and respiratory infections were the most common types of disease studied. Diabetes mellitus, chronic kidney diseases, and mental disorders were under-researched relative to their disease burden in most of the countries. The overall mean quality reporting score for HEE and BIA studies were 71/119 points (60%) and 7/10 points (70%), respectively; however, these assessments were made on different scales.

CONCLUSION

In Central America, health economic research is sparse and is considered as suboptimal quality for reporting. The findings reported information useful to other low- and middle-income countries with similar advances in the application of economics to promote health policy decision-making.

Cervical cancer prevention in El Salvador: A prospective evaluation of screening and triage strategies incorporating high-resolution microendoscopy to detect cervical precancer

Cervical cancer remains a leading cause of cancer death for women in low- and middle-income countries. The goal of our study was to evaluate screening and triage strategies, including high-resolution microendoscopy (HRME), to detect cervical abnormalities concerning for precancer at the point of care. Women (n = 1824) were enrolled at the Instituto de Cáncer de El Salvador. All underwent screening by both human papillomavirus (HPV) testing using careHPV and visual inspection with acetic acid (VIA). Screen-positives, along with 10% of screen-negatives, were invited to return for a follow-up examination that included triage with VIA, colposcopy and HRME imaging. Biopsies were taken of any abnormalities identified. If no abnormalities were identified, then the worst scoring site by HRME was biopsied. The sensitivities of HPV testing and VIA to screen for cervical intraepithelial neoplasia Grade 2 or more severe diagnoses (CIN2+) were 82.1% and 75% (P = .77), while the specificities were 90.4% and 80.9% (P < .001), respectively. The sensitivities of VIA, colposcopy and HRME as triage tests for CIN2+ were 82.1%, 82.1% and 71.4%, respectively (P ≥ .38). HRME had a significantly higher specificity (66.7%) than VIA (51.9%) (P < .001) and colposcopy (53.3%) (P < .001). When evaluating different theoretical screening and triage strategies, screening with HPV testing followed by triage with HRME would result in more women receiving appropriate care (97%) compared to screening with VIA (75%) or HPV alone (90%). Our findings demonstrate that screening with HPV is superior to VIA, and that triage with HRME imaging increases the specificity of detecting CIN2+ at the point of care in a low-resource setting.

Long Noncoding RNA WT1-AS Inhibits the Progression of Cervical Cancer by Sponging miR-205

Background: Cervical cancer (CC) is the second frequent cancer of women in developing countries. Plentiful studies proved that long noncoding RNA antisense of the tumor suppressor gene WT1 (WT1-AS) participated in the progression of CC. However, the role of WT1-AS remains unclear. This study investigated the potential mechanisms of WT1-AS in CC. Methods: The expression of WT1-AS and miR-205 were determined by quantitative real-time polymerase chain reaction. The cellular localization of WT1-AS in CC cells was detected by subcellular fractionation assay. The level of epithelial-mesenchymal transition (EMT)-related proteins of N-cadherin, E-cadherin, MMP9, and MMP2 were measured by Western blot. Moreover, cell cycle, apoptosis, migration, and invasion were detected by flow cytometry and transwell assay, respectively. The interrelation between WT1-AS and miR-205 was verified by dual-luciferase reporter and RNA immunoprecipitation assays. The role of WT1-AS in modifying CC growth was identified using xenograft tumor model. Results: WT1-AS was downregulated in cervical tissues and cell lines. WT1-AS was predominantly located in the cytoplasm of CC cells. Upregulation of WT1-AS promoted cell apoptosis, blocked cell cycle, migration, invasion, and EMT in vitro. Moreover, miR-205, as a target gene of WT1-AS, was increased in cervical tissues and cell lines. Besides, miR-205 mimic reversed the effect of WT1-AS upregulation on cell cycle, apoptosis, migration, invasion, and EMT. Also, WT1-AS caused the curb of xenograft tumor growth in vivo. Conclusion: Upregulation of WT1-AS suppressed CC development through sponging miR-205, providing experimental basis for clinical targeted treatment of CC.

Systematic review of model-based cervical screening evaluations

BACKGROUND

Optimising population-based cervical screening policies is becoming more complex due to the expanding range of screening technologies available and the interplay with vaccine-induced changes in epidemiology. Mathematical models are increasingly being applied to assess the impact of cervical cancer screening strategies.

METHODS

We systematically reviewed MEDLINE®, Embase, Web of Science®, EconLit, Health Economic Evaluation Database, and The Cochrane Library databases in order to identify the mathematical models of human papillomavirus (HPV) infection and cervical cancer progression used to assess the effectiveness and/or cost-effectiveness of cervical cancer screening strategies. Key model features and conclusions relevant to decision-making were extracted.

RESULTS

We found 153 articles meeting our eligibility criteria published up to May 2013. Most studies (72/153) evaluated the introduction of a new screening technology, with particular focus on the comparison of HPV DNA testing and cytology (n = 58). Twenty-eight in forty of these analyses supported HPV DNA primary screening implementation. A few studies analysed more recent technologies - rapid HPV DNA testing (n = 3), HPV DNA self-sampling (n = 4), and genotyping (n = 1) - and were also supportive of their introduction. However, no study was found on emerging molecular markers and their potential utility in future screening programmes. Most evaluations (113/153) were based on models simulating aggregate groups of women at risk of cervical cancer over time without accounting for HPV infection transmission. Calibration to country-specific outcome data is becoming more common, but has not yet become standard practice.

CONCLUSIONS

Models of cervical screening are increasingly used, and allow extrapolation of trial data to project the population-level health and economic impact of different screening policy. However, post-vaccination analyses have rarely incorporated transmission dynamics. Model calibration to country-specific data is increasingly common in recent studies.

Evaluation of a single-visit approach to cervical cancer screening and treatment in Guyana: feasibility, effectiveness and lessons learned

AIM

To evaluate a cervical cancer prevention project in Guyana utilizing visual inspection with acetic acid (VIA) and immediate cryotherapy in a single-visit approach; and to identify lessons learned to inform the improvement of cervical cancer prevention programs in Guyana and other low-resource settings.

METHODS

Service records from January 2009 to June 2012 were analyzed for 18 cervical cancer prevention sites across Guyana. Records included women's HIV status, data on visual inspection with acetic acid screening and treatment status for women's initial and 1-year follow-up screenings, provider training and retention. A process evaluation was conducted in 2011 to identify programmatic strengths and interventions for integration, scale-up and sustainability.

RESULTS

During the 42-month interval, 21,597 new screenings were performed, reaching 95% of HIV(+) women enrolled in care and 17% of women aged 25-49 years in Guyana. The VIA(+) rate was 13% (n = 2806); 85% of women eligible for cryotherapy received immediate treatment. Half of VIA(+) women treated with cryotherapy or loop electrosurgical excision procedure returned for a 1-year follow-up screening (n = 1027); 95% were VIA(-) at the second screening. Non-physician providers were more likely to continue offering services than physicians. Most programmatic challenges were related to systemic rather than technical/clinical issues.

CONCLUSION

The single-visit approach-based program is feasible, effective, and when scaled up, likely to have an impact on overall incidence of cervical cancer. Services can be shifted to non-physicians for scale-up of high-quality cervical cancer prevention services nationally. To ensure sustainability and expansion, support structures should be prioritized.

Evaluation of a 5-year cervical cancer prevention project in Indonesia: opportunities, issues, and challenges

AIM

The Cervical and Breast Cancer Prevention (CECAP) Project sought to develop a national model for cervical cancer prevention in Indonesia based on visual inspection with acetic acid (VIA) to detect abnormal changes in the cervix. The purpose of this study was to evaluate a pilot project introducing VIA and cryotherapy in Indonesia and to identify lessons learned that could be applied to the national scale-up of cervical cancer prevention services.

MATERIAL AND METHODS

Fifty-four months (July 2007 to December 2011) of service records at 17 health centers were abstracted and analyzed. The data were used to calculate the proportion of all women aged 30-50 who received VIA screening, the VIA-positive rate, the treatment rate, and the interval between screening and treatment.

RESULTS

The 45 050 women screened during the project included 24.4% of the total female population in the target age group in the catchment area. Throughout the 5-year project, 83.1% of VIA-positive women sought cryotherapy. During the last 18 months of the project, after data collection tools were revised to more accurately reflect when cryotherapy was received, 13% of women were treated on the same day that they were screened. Among the 74% of women treated within 1 month of screening, the mean interval between screening and treatment was 7.2 days.

CONCLUSION

As cervical cancer prevention services are scaled up throughout Indonesia, changes in the service delivery model and program management are needed to increase screening coverage, promote a single-visit approach, and ensure the quality of services.

A cross-sectional study to assess HPV knowledge and HPV vaccine acceptability in Mali

Despite a high prevalence of oncogenic human papilloma virus (HPV) infection and cervical cancer mortality, HPV vaccination is not currently available in Mali. Knowledge of HPV and cervical cancer in Mali, and thereby vaccine readiness, may be limited. Research staff visited homes in a radial pattern from a central location to recruit adolescent females and males aged 12-17 years and men and women aged ≥ 18 years (N = 51) in a peri-urban village of Bamako, Mali. Participants took part in structured interviews assessing knowledge, attitudes, and practices related to HPV, cervical cancer, and HPV vaccination. We found low levels of HPV and cervical cancer knowledge. While only 2.0% of respondents knew that HPV is a sexually transmitted infection (STI), 100% said they would be willing to receive HPV vaccination and would like the HPV vaccine to be available in Mali. Moreover, 74.5% said they would vaccinate their child(ren) against HPV. Men were found to have significantly greater autonomy in the decision to vaccinate themselves than women and adolescents (p = 0.005), a potential barrier to be addressed by immunization campaigns. HPV vaccination would be highly acceptable if the vaccine became widely available in Bamako, Mali. This study demonstrates the need for a significant investment in health education if truly informed consent is to be obtained for HPV vaccination. Potential HPV vaccination campaigns should provide more information about HPV and the vaccine. Barriers to vaccination, including the significantly lower ability of the majority of the target population to autonomously decide to get vaccinated, must also be addressed in future HPV vaccine campaigns.

Knowledge about HPV, relation between HPV and cervix cancer and acceptance of HPV vaccine in women in eastern region of Turkey

Objective

The aim of this study is to determine the knowledge of the women living in the eastern region of Turkey about human papillomavirus (HPV) and cervix cancer and their approaches to HPV vaccine.

Methods

The questionnaire forms were distributed to 1,052 patients who applied to the Gynecology Department of Elazig Training and Research Hospital. The subjects were recruited from the general gynecology outpatient clinic of the hospital. The patients from sexually transmitted disease and oncology outpatient clinics were not included in the study. The information about 945 women who completely filled in the questionnaire form was included into the study. The questions set forth in the questionnaire form consisting of 20 questions were prepared by taking the studies previously performed as model.

Results

Ninety-five percent of the women were married and 83.5% were housewives (unemployed). Thirteen percent of the women were illiterate, only 12% were graduated from university. Seventy-four percent of the women did not hear about HPV, 78.4% did not know about HPV vaccine, 63% did not know about the fact that some viruses cause cancer, and 83% did not know about the relation between HPV and cervix cancer. According to the multivariate analysis, free-of-charge vaccination, vaccinated relatives or friends, graduation from university and being under the age of 25 predict to accept the vaccine for themselves.

Conclusion

The young population and the women who graduated from university seem to be more well-informed about HPV and more sensitive about being vaccinated. In addition, free vaccination will ensure the expansion of the vaccine.

Prevent cervical cancer by screening with reliable human papillomavirus detection and genotyping

The incidence of cervical cancer is expected to rise sharply in China. A reliable routine human papillomavirus (HPV) detection and genotyping test to be supplemented by the limited Papanicolaou cytology facilities is urgently needed to help identify the patients with cervical precancer for preventive interventions. To this end, we evaluated a nested polymerase chain reaction (PCR) protocol for detection of HPV L1 gene DNA in cervicovaginal cells. The PCR amplicons were genotyped by direct DNA sequencing. In parallel, split samples were subjected to a Digene HC2 HPV test which has been widely used for "cervical cancer risk" screen. Of the 1826 specimens, 1655 contained sufficient materials for analysis and 657 were truly negative. PCR/DNA sequencing showed 674 infected by a single high-risk HPV, 188 by a single low-risk HPV, and 136 by multiple HPV genotypes with up to five HPV genotypes in one specimen. In comparison, the HC2 test classified 713 specimens as infected by high-risk HPV, and 942 as negative for HPV infections. The high-risk HC2 test correctly detected 388 (57.6%) of the 674 high-risk HPV isolates in clinical specimens, mislabeled 88 (46.8%) of the 188 low-risk HPV isolates as high-risk genotypes, and classified 180 (27.4%) of the 657 "true-negative" samples as being infected by high-risk HPV. It was found to cross-react with 20 low-risk HPV genotypes. We conclude that nested PCR detection of HPV followed by short target DNA sequencing can be used for screening and genotyping to formulate a paradigm in clinical management of HPV-related disorders in a rapidly developing economy.

Lessons learned from successful Papanicolaou cytology cervical cancer prevention in the Socialist Republic of Vietnam

In 1996, we documented that the burden of cervical cancer in Vietnam was associated with troop movements during the Vietnam War. Subsequently, establishment of Papanicolaou screening in southern Vietnam was associated with reductions in cervical cancer incidence from 29.2/100,000 in 1998 to 16/100,000 in 2003. This is one of the first English-language reports of a real-world cervical cancer prevention effort associated with a decisive impact on health outcomes in a contemporary developing country.

LESSONS LEARNED

if our ideological commitment is to improve health outcomes as rapidly as possible among as many people as possible, then Papanicolaou screening (with or without HPV or visual screening) must be implemented without further delay in any setting where cervical screening is appropriate but unavailable; consideration must be given to HPV vaccination after, rather than before, full coverage of target demographic groups by screening services has been achieved and/or the possibility has been excluded that HPV vaccination may be ineffective for cancer prevention. Competing ideological commitments engender imprudent yet commercially useful alternative strategies prone to decelerate global reductions in mortality by suppressing the more-rapid uptake of less-expensive open-source technology in favor of the less-rapid uptake of more-expensive proprietary technologies with uncertain real-world advantages and unfavorable real-world operational limitations. Global cervical cancer prevention efforts will become more effective if global health leaders, including the Bill & Melinda Gates Foundation, embrace an ideological commitment to improving health outcomes as rapidly as possible among as many people as possible and assimilate the policy implications of that commitment.

Visual inspection methods for cervical cancer prevention

The need for simple, cost-effective screening approaches for cervical cancer prevention in low-resource countries has led to the evaluation of visual screening with 3-5% acetic acid. The low reproducibility and wide variation in accuracy reflect the subjective nature of the test. Pooled sensitivity, specificity, positive and negative predictive values were 80%, 92%, 10% and 99%, respectively, for detecting cervical intraepithelial neoplasia grade 2 or worse lesions. Realistic sensitivity of a quality- assured single visual inspection with acetic acid is around 50%. A single round of visual inspection with acetic acid screening has been associated with a 25-35% reduction in cervical cancer incidence and the frequency of cervical intraepithelial neoplasia grade 2 or worse lesions in randomised-controlled trials. Despite all its limitations, implementing visual inspection with acetic acid screening in low-resource countries may provide a pragmatic approach to building up human resources and infrastructure that may facilitate the highly anticipated low-cost, rapid human papilloma virus testing in the near future.