A population-based evaluation of cervical screening in the United States: 2008-2011

Evolution of Pathological Techniques for the Screening of Cervical Cancer: A Comprehensive Review

The evolutionary journey of cervical cancer screening has been a major medical success story, considering the substantial role it has played in dwindling the disease burden. Through sustained collaborative efforts within the medical community, significant advances have been made from the humble yet path-breaking conventional Pap smear to the current automated screening systems and human papillomavirus (HPV) molecular testing. With the integration of artificial intelligence into screening techniques, we are currently at the precipice of circumventing the pitfalls of manual cytology readings and improving the efficiency of the screening systems by a significant margin. Despite the technological milestones traversed, the high logistics and operational cost, besides the technical know-how of operating the automated systems, can pose a major practical challenge in the widespread adoption of these advanced techniques in cervical cancer screening programs. This would suggest the need to adopt strategies that are tailored to the demands and needs of the different settings keeping their limitations in mind. This review aims to take the reader through the entire evolutionary journey of cervical cancer screening programs, highlight the individual merits and demerits of each technique, and discuss the recommendations from the major global guidelines.

Impact of HPV testing in opportunistic cervical screening: Support for primary HPV screening in the United States

Human papillomavirus (HPV) testing for cervical screening increases diagnosis of precancer and reduces the incidence of cervical cancer more than cytology alone. However, real-world evidence from diverse practice settings is lacking for the United States (U.S.) to support clinician adoption of primary HPV screening. Using a population-based registry, which captures all cervical cytology (with or without HPV testing) and all cervical biopsies, we conducted a real-world evidence study of screening in women aged 30 to 64 years across the entire state of New Mexico. Negative cytology was used to distinguish cotests from reflex HPV tests. A total of 264 198 cervical screening tests (with exclusions based on clinical history) were recorded as the first screening test between 2014 and 2017. Diagnoses of cervical intraepithelial neoplasia grades 2 or 3 or greater (CIN2+, CIN3+) from 2014 to 2019 were the main outcomes. Of cytology-negative screens, 165 595 (67.1%) were cotests and 4.8% of these led to biopsy within 2 years vs 3.2% in the cytology-only group. Among cytology-negative, HPV tested women, 347 of 398 (87.2%) CIN2+ cases were diagnosed in HPV-positive women, as were 147 of 164 (89.6%) CIN3+ cases. Only 29/921 (3.2%) CIN3+ and 67/1964 (3.4%) CIN2+ cases were diagnosed in HPV-negative, cytology-positive women with biopsies. Under U.S. opportunistic screening, across a diversity of health care delivery practices, and in a population suffering multiple disparities, we show adding HPV testing to cytology substantially increased the yield of CIN2+ and CIN3+. CIN3+ was rarely diagnosed in HPV-negative women with abnormal cytology, supporting U.S. primary HPV-only screening.

Survival of cervical cancer patients in Brunei Darussalam: 2002-2017

Objective

Cervical cancer is the fourth leading cause of cancer deaths among Bruneian women. This study aims to investigate the survival rate of cervical cancer patients in Brunei Darussalam between 2002 and 2017, to compare survival of cervical cancer patients between two periods: 2002-2009 and 2010-2017 and to identify prognostic factors of cervical cancer.

Methods

A retrospective cohort study on cervical cancer patients registered in Brunei Darussalam Cancer Registry between 2002 and 2017. De-identified data from the registry was extracted and survival analysis was performed using Kaplan-Meier estimator, log-rank test and multiple Cox regression analysis.

Results

The 1-, 3- and 5-year survival rates of cervical cancer patients in Brunei Darussalam were 87.3%, 77.4% and 72.5% respectively from 2002 to 2017. The 5-year survival rate for 2002-2009 and 2010-2017 were 77.3% and 69.1% respectively. The risk of mortality was significantly higher in 2010-2017 compared to 2002-2009 after adjusting for variables (Adjusted HR = 1.59; 95% CI: 1.08, 2.40; p = 0.019). Patients with distant cancer (Adjusted HR = 11.21; 95% CI: 6.18, 20.30; p < 0.001) had the highest risk of mortality.

Conclusion

The 5-year survival rate of cervical cancer patients in Brunei Darussalam was 72.5%, which ranks relatively high globally. However, increased mortality among elderly patients, and patients diagnosed with cervical cancers at the later stages, calls for public health efforts to raise awareness, early detection, and disease management.

A model-based analysis of the health impacts of COVID-19 disruptions to primary cervical screening by time since last screen for current and future disruptions

We evaluated how temporary disruptions to primary cervical cancer (CC) screening services may differentially impact women due to heterogeneity in their screening history and test modality. We used three CC models to project the short- and long-term health impacts assuming an underlying primary screening frequency (i.e., 1, 3, 5, or 10 yearly) under three alternative COVID-19-related screening disruption scenarios (i.e., 1-, 2-, or 5-year delay) versus no delay in the context of both cytology-based and human papillomavirus (HPV)-based screening. Models projected a relative increase in symptomatically detected cancer cases during a 1-year delay period that was 38% higher (Policy1-Cervix), 80% higher (Harvard), and 170% higher (MISCAN-Cervix) for underscreened women whose last cytology screen was 5 years prior to the disruption period compared with guidelines-compliant women (i.e., last screen 3 years prior to disruption). Over a woman's lifetime, temporary COVID-19-related delays had less impact on lifetime risk of developing CC than screening frequency and test modality; however, CC risks increased disproportionately the longer time had elapsed since a woman's last screen at the time of the disruption. Excess risks for a given delay period were generally lower for HPV-based screeners than for cytology-based screeners. Our independent models predicted that the main drivers of CC risk were screening frequency and screening modality, and the overall impact of disruptions from the pandemic on CC outcomes may be small. However, screening disruptions disproportionately affect underscreened women, underpinning the importance of reaching such women as a critical area of focus, regardless of temporary disruptions.

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

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

Key Words

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

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MESH Headings

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

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Grants

• 21070 Cancer Research UK
• 27046 Cancer Research UK
• C27045/A27046 Cancer Research UK
• Cancer Research UK
• National Institute of Allergy and Infectious Diseases

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Affiliation(s)

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

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Health impacts of COVID-19 disruptions to primary cervical screening by time since last screen: A model-based analysis for current and future disruptions

Background

We evaluated how temporary disruptions to primary cervical cancer (CC) screening services may differentially impact women due to heterogeneity in their screening history and test modality.

Methods

We used three CC models to project the short- and long-term health impacts assuming an underlying primary screening frequency (i.e., 1, 3, 5, or 10 yearly) under three alternative COVID-19-related screening disruption scenarios (i.e., 1-, 2- or 5-year delay) versus no delay, in the context of both cytology-based and HPV-based screening.

Results

Models projected a relative increase in symptomatically-detected cancer cases during a 1-year delay period that was 38% higher (Policy1-Cervix), 80% higher (Harvard) and 170% higher (MISCAN-Cervix) for under-screened women whose last cytology screen was 5 years prior to the disruption period compared with guidelines-compliant women (i.e., last screen three years prior to disruption). Over a woman's lifetime, temporary COVID-19-related delays had less impact on lifetime risk of developing CC than screening frequency and test modality; however, CC risks increased disproportionately the longer time had elapsed since a woman's last screen at the time of the disruption. Excess risks for a given delay period were generally lower for HPV-based screeners than for cytology-based screeners.

Conclusions

Our independent models predicted that the main drivers of CC risk were screening frequency and screening modality, and the overall impact of disruptions from the pandemic on CC outcomes may be small. However, screening disruptions disproportionately affect under-screened women, underpinning the importance of reaching such women as a critical area of focus, regardless of temporary disruptions.

Funding

This study was supported by funding from the National Cancer Institute (U01CA199334). The contents are solely the responsibility of the authors and do not necessarily represent the official views of the National Cancer Institute. Megan A Smith receives salary support from the National Health and Medical Research Council, Australia (APP1159491) and Cancer Institute NSW (ECF181561). Matejka Rebolj is funded by Cancer Research UK (reference: C8162/A27047). James O'Mahony is funded by Ireland's Health Research Board (EIA2017054). Karen Canfell receives salary support from the National Health and Medical Research Council, Australia (APP1194679). Emily A. Burger receives salary support from the Norwegian Cancer Society.

Screening technologies for cervical cancer: Overview

Ever since the introduction of the Papanicolaou (PAP) smear test was published in 1941 in American Journal of Obstetrics and Gynecology, PAP test linked with definitive treatment has prevented millions of women from cervical cancer in the developed countries. Due to limited availability of resources, a lack of infrastructure and difficulty in getting highly trained professionals, widespread implementation of PAP test dependent cervical cancer screening program has not been established in low and middle income countries such as India. Therefore, after availability of non-cytological tests such as visual inspection on acetic acid (VIA) and human papillomavirus (HPV) DNA test, there is a paradigm shift in cervical cancer screening methods. In past two decades, various research work has convincingly established the utility of VIA and HPV test in developing countries. The evidences were evaluated by the World Health Organization (WHO) and recommendations have been recently published for comprehensive cervical cancer control strategies for the low and middle income countries. For any successful screening program, achieving high coverage (>70%) of the target population rather than frequent screening is the most important determinant. It is also equally important to ensure appropriate investigations of the screen positive women to establish the disease and treatment of the screen detected cases of cervical intra epithelial neoplasia (CIN) and cancer. HPV testing is the WHO recommended test for cervical cancer screening especially in view of widespread HPV vaccination in young population leading to lower prevalence of CIN and other HPV related diseases.

Median Age at HPV Infection Among Women in the United States: A Model-Based Analysis Informed by Real-world Data

Background

The US Advisory Committee for Immunization Practices (ACIP) recommended shared clinical decision-making for human papillomavirus (HPV) vaccination of individuals aged 27 to 45 years (mid-adults) in June 2019. Determining the median age at causal HPV infection and CIN2+ diagnosis based on the natural history of HPV disease can help elucidate the incidence of HPV infections and the potential benefits of vaccination in mid-adults.

Methods

Real-world data on CIN2+ diagnosis from the prevaccine era were sourced from a statewide surveillance registry in Connecticut. Age distribution of CIN2+ diagnosis in 2008 and 2009 was estimated. A discrete event simulation model was developed to predict the age distribution of causal HPV infection. The optimal age distribution of causal HPV infection provided the best goodness-of-fit statistic to compare the predicted vs real-world age distribution of CIN2+ diagnosis.

Results

The median age at CIN2+ diagnosis from 2008 through 2009 in Connecticut was 28 years. The predicted median age at causal HPV infection was estimated to be 23.9 years. There was a difference of 5.2 years in the median age at acquisition of causal HPV infection and the median age at CIN2+ diagnosis.

Conclusions

Real-world data on CIN2+ diagnosis and model-based analysis indicate a substantial burden of infection and disease among women aged 27 years or older, which supports the ACIP recommendation to vaccinate some mid-adults. When natural history is known, this novel approach can also help determine the timing of causal infections for other commonly asymptomatic infectious diseases.

Burden of Mycoplasma genitalium and Bacterial Coinfections in a Population-Based Sample in New Mexico

ABSTRACT

In this population-based US study, the overall prevalence of Mycoplasma genitalium was 1.95% (95% confidence interval [CI], 1.62%-2.34%), declining from 6.12% (95% CI, 4.72%-7.92%) in women aged 21 to 24 years to 0.48% (95% CI, 0.25%-0.94%) in women aged 40 to 64 years. The prevalence of coinfections with Chlamydia trachomatis and Trichomonas vaginalis was low.

Clinical follow-up practices after cervical cancer screening by co-testing: A population-based study of adherence to U.S. guideline recommendations

Failure to follow-up women after abnormal cervical screening could lead to cervical cancers, yet little is known about adherence to recommended follow-up after abnormal co-testing [cytology and high-risk human papillomavirus (hrHPV) testing]. We documented clinical management following cervical screening by co-testing in a diverse population-based setting. A statewide surveillance program for cervical screening, diagnosis, and treatment was used to investigate all cytology, hrHPV and biopsy reports in the state of New Mexico from January 2015 through August 2019. Guideline-adherent follow-up after co-testing required 1) biopsy within 6 months for low-grade cytology if positive for hrHPV, for high-grade cytology irrespective of hrHPV, and for HPV 16/18 positive results irrespective of cytology and; 2) repeat co-testing within 18 months if cytology was negative and hrHPV test was positive (excluding types 16/18). Screening co-tests (2015-2017) for 164,522 women were analyzed using descriptive statistics, Kaplan Meier curves, and pairwise comparisons between groups. Guideline adherence was highest when both cytology and hrHPV tests were abnormal, ranging from 61.7% to 80.3%. Guideline-adherent follow-up was lower for discordant results. Women with high-grade cytology were less likely to receive a timely biopsy when hrHPV-testing was negative (48.1%) versus positive (83.3%) (p < 0.001). Only 47.9% of women received biopsies following detection of HPV16/18 with normal cytology, and 30.8% received no follow-up within 18-months. Among women with hrHPV-positive normal cytology without evidence of HPV 16/18 infection, 51% received no follow-up within 18 months. Provider education and creation of robust recall systems may help ensure appropriate follow-up of abnormal screening results.

Adherence to National Guidelines on Cervical Screening: A Population-Based Evaluation from a Statewide Registry

In 2012, national recommendations for cervical-cancer screening of women aged 30-64 years were quinquennial human papillomavirus and cytology co-testing or triennial cytology. Data from a state-wide surveillance program in New Mexico demonstrated 65.2% (95% confidence interval [95%CI]= 64.6%% to 65.7%) of women screened in 2019 had negative co-test within the last 3 years. Percentages of women screened in 2013, 2016, and 2019 with a prior negative co-test more than 5 and up to 7 years ago were 2.6% (95% CI = 2.2% to 2.9%), 2.1% (95% CI = 1.9% to 2.2%), and 6.5% (95% CI = 6.2% to 6.8%), respectively (2-sided P trend<.001). Percentages of women screened in 2013, 2016, and 2019 with a prior negative cytology more than 5 and up to 7 years ago were 3.8% (95% CI = 3.7% to 3.9%), 9.0% (95% CI = 8.7% to 9.3%), and 14.9% (95% CI = 14.4% to 15.4%), respectively (2-sided P trend<.001). Thus, in 2019, only 12.7% (95% CI = 12.4% to 13.1%) of the 30,215 women aged 30-64 years underwent co-testing and 27.7% (95% CI = 27.1% to 28.3%) of the 18,733 underwent cytology at the recommended interval. The observed under- and over-screening could result in increases in cervical-cancer incidence and harms and costs, respectively.

Providing more balanced information on the harms and benefits of cervical cancer screening: A randomized survey among US and Norwegian women

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Additional information did not impact intentions to participate in CC screening.

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Additional information increased uncertainty to seek precancer treatment in Norway.

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Women reported strong system-specific preferences for sources of information.

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Having a prior Pap-test was an important predictor of intentions-to-participate.

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Socioeconomic factors influenced follow-up intentions in the U.S. but not in Norway.

We aimed to identify how additional information about benefits and harms of cervical cancer (CC) screening impacted intention to participate in screening, what type of information on harms women preferred receiving, from whom, and whether it differed between two national healthcare settings. We conducted a survey that randomized screen-eligible women in the United States (n = 1084) and Norway (n = 1060) into four groups according to the timing of introducing additional information. We found that additional information did not significantly impact stated intentions-to-participate in screening or follow-up testing in either country; however, the proportion of Norwegian women stating uncertainty about seeking precancer treatment increased from 7.9% to 14.3% (p = 0.012). Women reported strong system-specific preferences for sources of information: Norwegians (59%) preferred it come from a national public health agency while Americans (59%) preferred it come from a specialist care provider. Regression models revealed having a prior Pap-test was the most important predictor of intentions-to-participate in both countries, while having lower income reduced the probabilities of intentions-to-follow-up and seek precancer treatment among U.S. women. These results suggest that additional information on harms is unlikely to reduce participation in CC screening but could increase decision uncertainty to seek treatment. Providing unbiased information would improve on the ethical principle of respect for autonomy and self-determination. However, the clinical impact of additional information on women’s understanding of the trade-offs involved with CC screening should be investigated. Future studies should also consider country-specific socioeconomic barriers to screening if communication re-design initiatives aim to improve CC screening participation.

Human papillomavirus vaccination for adults aged 30 to 45 years in the United States: A cost-effectiveness analysis

BACKGROUND

A nonavalent human papillomavirus (HPV) vaccine has been licensed for use in women and men up to age 45 years in the United States. The cost-effectiveness of HPV vaccination for women and men aged 30 to 45 years in the context of cervical cancer screening practice was evaluated to inform national guidelines.

METHODS AND FINDINGS

We utilized 2 independent HPV microsimulation models to evaluate the cost-effectiveness of extending the upper age limit of HPV vaccination in women (from age 26 years) and men (from age 21 years) up to age 30, 35, 40, or 45 years. The models were empirically calibrated to reflect the burden of HPV and related cancers in the US population and used standardized inputs regarding historical and future vaccination uptake, vaccine efficacy, cervical cancer screening, and costs. Disease outcomes included cervical, anal, oropharyngeal, vulvar, vaginal, and penile cancers, as well as genital warts. Both models projected higher costs and greater health benefits as the upper age limit of HPV vaccination increased. Strategies of vaccinating females and males up to ages 30, 35, and 40 years were found to be less cost-effective than vaccinating up to age 45 years, which had an incremental cost-effectiveness ratio (ICER) greater than a commonly accepted upper threshold of $200,000 per quality-adjusted life year (QALY) gained. When including all HPV-related outcomes, the ICER for vaccinating up to age 45 years ranged from $315,700 to $440,600 per QALY gained. Assumptions regarding cervical screening compliance, vaccine costs, and the natural history of noncervical HPV-related cancers had major impacts on the cost-effectiveness of the vaccination strategies. Key limitations of the study were related to uncertainties in the data used to inform the models, including the timing of vaccine impact on noncervical cancers and vaccine efficacy at older ages.

CONCLUSIONS

Our results from 2 independent models suggest that HPV vaccination for adult women and men aged 30 to 45 years is unlikely to represent good value for money in the US.

Impact of screening on cervical cancer incidence: A population-based case-control study in the United States

Cervical cancer is widely preventable through screening, but little is known about the duration of protection offered by a negative screen in North America. A case-control study was conducted with records from population-based registries in New Mexico. Cases were women diagnosed with cervical cancer in 2006-2016, obtained from the Tumor Registry. Five controls per case from the New Mexico HPV Pap Registry were matched to cases by sex, age and place of residence. Dates and results of all cervical screening and diagnostic tests since 2006 were identified from the pap registry. We estimated the odds ratio of nonlocalized (Stage II+) and localized (Stage I) cervical cancer associated with attending screening in the 3 years prior to case-diagnosis compared to women not screened in 5 years. Of 876 cases, 527 were aged 25-64 years with ≥3 years of potential screening data. Only 38% of cases and 61% of controls attended screening in a 3-year period. Women screened in the 3 years prior to diagnosis had 83% lower risk of nonlocalized cancer (odds ratio [OR] = 0.17, 95% CI: 0.12-0.24) and 48% lower odds of localized cancer (OR = 0.52, 95% CI: 0.38-0.72), compared to women not screened in the 5 years prior to diagnosis. Women remained at low risk of nonlocalized cancer for 3.5-5 years after a negative screen compared to women with no negative screens in the 5 years prior to diagnosis. Routine cervical screening is effective at preventing localized and nonlocalized cervical cancers; 3 yearly screening prevents 83% of nonlocalized cancers, with no additional benefit of more frequent screening. Increasing screening coverage remains essential to further reduce cervical cancer incidence.

Impact of introduction of endocervical brush on cytologic detection of cervical epithelial cell abnormalities: A clinical audit of 13-years' experience at a cancer research centre

OBJECTIVE

To study the temporal trends in cytologic detection of cervical epithelial cell abnormalities (ECA) and to evaluate the impact of introduction of endocervical brush sampling on detection of ECA.

STUDY DESIGN

This was a cross-sectional study of conventional cervical smears collected over a 13 year period (2006-2018). The study was divided into two time periods (TP)-TP1 (2006-2014, 67,437 smears) using only extended tip Ayre's spatula and TP2 (2015-2018; 36,746 smears) when Cytobrush Papsmear kit (Ayre's spatula + endocervical brush) was used. The unsatisfactory rate and detection rate of ECA was compared between the two TPs.

RESULTS

The unsatisfactory rate reduced from 4.7 % in TP 1-1.5% in TP2 (P < 0.001). The frequency of ECA was 1.5 % in TP1 and 1.9 % in TP2 (P < 0.001). A significantly higher number of ASC-H and HSIL were detected in TP2. There was a substantial improvement (3.7 times) in detection of glandular abnormalities overall (P < 0.001), as also for both the qualifiers AGC- NOS (4.4 times) and AGC- FN (3.3 times) in TP2.

CONCLUSIONS

Cervical sampling using combined spatula and endocervical brush reduces the unsatisfactory rate and improves the detection of both squamous and glandular precancerous lesions. Hence, this sampling procedure should be recommended for all laboratories practicing conventional cervical cytology.

How the Cervical Microbiota Contributes to Cervical Cancer Risk in Sub-Saharan Africa

Despite ongoing efforts, sub-Saharan Africa faces a higher cervical cancer burden than anywhere else in the world. Besides HPV infection, definitive factors of cervical cancer are still unclear. Particular states of the cervicovaginal microbiota and viral infections are associated with increased cervical cancer risk. Notably, HIV infection, which is prevalent in sub-Saharan Africa, greatly increases risk of cervicovaginal dysbiosis and cervical cancer. To better understand and address cervical cancer in sub-Saharan Africa, a better knowledge of the regional cervicovaginal microbiome is required This review establishes current knowledge of HPV, HIV, cervicovaginal infections, and the cervicovaginal microbiota in sub-Saharan Africa. Because population statistics are not available for the region, estimates are derived from smaller cohort studies. Microbiota associated with cervical inflammation have been found to be especially prevalent in sub-Saharan Africa, and to associate with increased cervical cancer risk. In addition to high prevalence and diversity of HIV and HPV, intracellular bacterial infections such as Chlamydia, Gonorrhea, and Mycoplasma hominis are much more common than in regions with a low burden of cervical cancer. This suggests the prevalence of cervical cancer in sub-Saharan Africa may be partially attributed to increased cervical inflammation resulting from higher likelihood of cervical infection and/or microbial dysbiosis.

Overview of Centers for Disease Control and Prevention's Case Investigation of Cervical Cancer Study

Background: Despite advances in cervical cancer screening, a significant number of women in the United States have not received adequate screening. Studies have suggested that approximately half of the women who developed cervical cancer were not adequately screened. The Centers for Disease Control and Prevention (CDC) Case Investigation of Cervical Cancer (CICC) Study took a unique approach to reconstruct the time before a woman's cervical cancer diagnosis and understand the facilitators and barriers to screening and care. This article provides an overview of the study. Methods: This study included all cervical cancer survivors diagnosed with invasive cervical cancer aged 21 years and older in three U.S. states from 2014-2016. The study design consisted of three different data collection methods, including comprehensive registry data, a mailed survey, and medical chart abstraction. This overview compares the characteristics of cervical cancer survivors in the three states by study participation and eligibility status. Results: Registries identified 2,748 women diagnosed with invasive cervical cancer. Of these, 1,730 participants were eligible for participation, 28% (n = 481) enrolled in the study and 23% (n = 400) consented to the medical chart abstraction. Conclusion: The CICC Study is unique in that it addresses, with medical record verification, the medical history of woman 5 years before their cervical cancer diagnosis as well as provides information from the woman on her health care behaviors. This study provides data on a general population of cervical cancer survivors in three states that could be used to guide interventions to increase cervical cancer screening.

Perceived Susceptibility to Cervical Cancer among African American Women in the Mississippi Delta: Does Adherence to Screening Matter?

BACKGROUND

Although preventive measures have greatly decreased the national burden of cervical cancer, racial/ethnic and geographic disparities remain, including the disproportionate incidence and mortality among African American women in the Mississippi Delta. Along with structural barriers, health perceptions and cultural beliefs influence participation in cervical screening. This study examined perceived susceptibility to cervical cancer among African American women in the Delta across three groups: 1) women attending screening appointments (screened), 2) women attending colposcopy clinic following an abnormal Papanicolaou test (colposcopy), and 3) women with no screening in 3 years or longer (unscreened/underscreened).

METHODS

Data were collected during a study assessing the feasibility/acceptability of self-collected sampling for human papillomavirus (HPV) testing as a cervical screening modality. A questionnaire assessed demographics, health care access, and cervical cancer knowledge and beliefs (including perceived susceptibility). Participants were asked, "Do you think you are at risk for cervical cancer?", and responses included yes, no, and I don't know. Multinomial logistic regression models compared variables associated with answers among each group.

RESULTS

Of 524 participants, one-half did not know if they were at risk of cervical cancer (50%) or HPV exposure (53%). Between the unscreened/underscreened (n = 160), screened (n = 198), and colposcopy (n = 166) groups, age (p < .001), education (p = .02), and perceived risk of HPV exposure (p < .01) differed. Older age and younger age at first intercourse (unscreened/underscreened), family history and screening recommendations (screened), and family history and perceived risk of HPV exposure (colposcopy) were associated with perceived susceptibility to cervical cancer.

CONCLUSIONS

Differences in the perceived susceptibility to cervical cancer exist between African American women in the Delta. Understanding these variations can help in developing strategies to promote screening among this population with a high burden of disease.

Screening for Cervical Cancer in Primary Care: A Decision Analysis for the US Preventive Services Task Force

IMPORTANCE

Evidence on the relative benefits and harms of primary high-risk human papillomavirus (hrHPV) testing is needed to inform guidelines.

OBJECTIVE

To inform the US Preventive Services Task Force by modeling the benefits and harms of various cervical cancer screening strategies.

DESIGN, SETTING, AND PARTICIPANTS

Microsimulation model of a hypothetical cohort of women initiating screening at age 21 years.

EXPOSURES

Screening with cytology, hrHPV testing, and cytology and hrHPV cotesting, varying age to switch from cytology to hrHPV testing or cotesting (25, 27, 30 years), rescreening interval (3, 5 years), and triage options for hrHPV-positive results (16/18 genotype, cytology testing). Current guidelines-based screening strategies comprised cytology alone every 3 years starting at age 21 years, with or without a switch to cytology and hrHPV cotesting every 5 years from ages 30 to 65 years. Complete adherence for all 19 strategies was assumed.

MAIN OUTCOMES AND MEASURES

Lifetime number of tests, colposcopies, disease detection, false-positive results, cancer cases and deaths, life-years, and efficiency ratios expressing the trade-off of harms (ie, colposcopies, tests) vs benefits (life-years gained, cancer cases averted). Efficient strategies were those that yielded more benefit and less harm than another strategy or a lower harm to benefit ratio than a strategy with less harms.

RESULTS

Compared with no screening, all modeled cervical cancer screening strategies were estimated to result in substantial reductions in cancer cases and deaths and gains in life-years. The effectiveness of screening across the different strategies was estimated to be similar, with primary hrHPV-based and alternative cotesting strategies having slightly higher effectiveness and greater harms than current guidelines-based cytology testing. For example, cervical cancer deaths associated with the guidelines-based strategies ranged from 0.30 to 0.76 deaths per 1000 women, whereas new strategies involving primary hrHPV testing or cotesting were associated with fewer cervical cancer deaths, ranging from 0.23 to 0.29 deaths per 1000 women. In all analyses, primary hrHPV testing strategies occurring at 5-year intervals were efficient. For example, 5-year primary hrHPV testing (cytology triage) based on switching from cytology to hrHPV screening at ages 30 years, 27 years, and 25 years had ratios per life-year gained of 73, 143, and 195 colposcopies, respectively. In contrast, strategies involving 3-year hrHPV testing had much higher ratios, ranging from 2188 to 3822 colposcopies per life-year gained. In most analyses, strategies involving cotesting were not efficient.

CONCLUSIONS AND RELEVANCE

In this microsimulation modeling study, it was estimated that primary hrHPV screening may represent a reasonable balance of harms and benefits when performed every 5 years. Switching from cytology to hrHPV testing at age 30 years yielded the most efficient harm to benefit ratio when using colposcopy as a proxy for harms.

Impact of Widespread Cervical Cancer Screening: Number of Cancers Prevented and Changes in Race-specific Incidence

OBJECTIVES

With recent approval of standalone HPV testing and increasing uptake of HPV vaccination, some have postulated that we are moving toward a "post-Pap" era of cervical cancer prevention. However, the total number cases that have been prevented by Pap smear screening as well as its impact on racial disparities are unknown.

METHODS

We estimated national cervical cancer incidence from 1976 to 2009 using the Surveillance, Epidemiology, and End Result database. Screening data were obtained from the literature and National Cancer Institute Progress Reports. We examined early, late, and race-specific trends in cancer incidence, and calculated the estimated number of cancers prevented over the past 3 decades.

RESULTS

From 1976 to 2009, there was a significant decrease in the incidence of early-stage cervical cancer, from 9.8 to 4.9 cases per 100,000 women (P<0.001). Late-stage disease incidence also decreased, from 5.3 to 3.7 cases per 100,000 women (P<0.001). The incidence among black women decreased from 26.9 to 9.7 cases per 100,000 women (P<0.001), a greater decline compared with that of white women and women of other races. After adjusting for "prescreening era" rates of cervical cancer, we estimate that Pap smears were associated with a reduction of between 105,000 and 492,000 cases of cervical cancer over the past 3 decades in the United States.

CONCLUSIONS

A large number of early-stage and late-stage cervical cancers were prevented and racial disparity in cancer rates were reduced during an era of widespread Pap smear screening.

Understanding the cervical screening behaviour of Chinese women: The role of health care system and health professions

BACKGROUND

In China, cervical cancer cases are increasing, making an impact on the worldwide burden of cervical cancer. Despite the initiatives undertaken by the Chinese government, the current coverage of cervical screening in China remains suboptimal. There is an urgent need to identify the facilitators and barriers associated with the uptake of cervical cancer screening among the Chinese population.

PURPOSE

The study aimed to explore the experiences and perceptions of cervical cancer screening of mainland Chinese women in relation to their screening behaviour, particularly in the aspects of health care system and health profession roles.

METHODS

A qualitative research was conducted using semi-structured interviews. A total of 27 Chinese women aged 25 to 50 (both screened and non-screened women) completed the interviews. The analysis of the interview data was undertaken inductively using latent content analysis.

DISCUSSION AND CONCLUSION

Results showed that organised health examination programmes provide a good basis for integrating cervical screening into broader checks on the health of women, and utilising different networks of social support facilitate the utilisation of the screening service. However, education on cervical cancer and screening must be made more generally available. More importantly, there is a need for a more participatory and empowering exchange in the encounter between health professions and these women. Appropriate training program is strongly recommended for health professions about communicate skills with patients. Future work should focus on identifying strategies to overcome the barriers to cervical screening related to health care system and medical professions among this population.

Uptake of HPV testing and extended cervical cancer screening intervals following cytology alone and Pap/HPV cotesting in women aged 30-65 years

OBJECTIVE

To evaluate the adoption of HPV testing and recommended extended cervical cancer screening intervals in clinical practice, we described yearly uptake of Pap/HPV cotesting and estimated length of time between normal screens by patient characteristics.

METHODS

We examined 55,575 Pap/HPV records from 27,035 women aged 30-65 years from the Johns Hopkins Hospital Pathology Data System between 2006 and 2013. Cotest uptake and median times to next screening test for cotests and cytology only were calculated. Adjusted hazard ratios were estimated using Cox proportional hazards models, with random effects adjustment for clustering within clinic.

RESULTS

Cotest usage increased from < 10% in 2006 to 78% in 2013. The median time to next screening test following normal cytology alone remained constant around 1.5 years. Screening intervals following a dual-negative cotest increased from 1.5 years in 2006/2007 to 2.5 years in 2010, coincident with increases in the proportion of women cotested. Intervals following a dual negative cotest were longer among Medicare patients (3 years) compared with privately insured women (2.5 years), and shorter among black (2 years) compared with white women (2.8 years).

CONCLUSION

By mid-2013 we observed broad adoption of Pap/HPV cotesting in routine screening in a large academic medical center. Increased screening intervals were observed only among cotested women, while those screened by cytology alone continued to be screened almost annually. The influence of different combinations of race and insurance on screening intervals should be further evaluated to ensure balance of screening risks and benefits in the U.S.

POPULATION

Outcomes in Women With Cytology Showing Atypical Squamous Cells of Undetermined Significance With vs Without Human Papillomavirus Testing

IMPORTANCE

Little is known about the long-term yield of high-grade cervical intraepithelial neoplasia (CIN) and the influence on biopsy and treatment rates of human papillomavirus (HPV) triage of cytology showing atypical squamous cells of undetermined significance (hereafter ASC-US cytology).

OBJECTIVE

To examine 5-year outcomes after ASC-US cytology with vs without HPV testing.

DESIGN, SETTING, AND PARTICIPANTS

In this observational study, all cervical cytology and HPV testing reports from January 1, 2007, to December 31, 2012, were obtained for women throughout New Mexico and linked to pathology reports. The dates of the analysis were May 4, 2015, to January 13, 2017.

MAIN OUTCOMES AND MEASURES

Influence of HPV testing on disease yield, time to histologically confirmed disease, and biopsy or loop electrosurgical excision procedure rates.

RESULTS

A total of 457 317 women (mean [SD] age, 39.8 [12.5] years) with a screening test were recorded between 2008 and 2012, and 20 677 (4.5%) of the first cytology results per woman were reported as ASC-US. CIN grade 3 or more severe (CIN3+) lesions were detected in 2.49% of women with HPV testing vs 2.15% of women without HPV testing (P = .23). Time to CIN3+ detection was much shorter in those with HPV testing vs those without testing (median, 103 vs 393 days; P < .001). CIN grade 1 was detected in 11.6% of women with HPV testing vs 6.6% without testing (relative risk, 1.76; 95% CI, 1.56-2.00; P < .001). Loop electrosurgical excision procedure rates within 5 years were 20.0% higher in those who underwent HPV testing, resulting in more CIN2+ and CIN3+ detection.

CONCLUSIONS AND RELEVANCE

Human papillomavirus testing led to faster and more complete diagnosis of cervical disease, but 55.8% more biopsies and 20.0% more loop electrosurgical excision procedures were performed. In those tested, virtually all high-grade disease occurred in the 43.1% of women who were HPV positive, allowing clinical resources to be focused on women who need them most. These data provide essential information for cervical screening guidelines and public health policy.

Cervical Cancer Screening and Incidence by Age: Unmet Needs Near and After the Stopping Age for Screening

INTRODUCTION

Leading professional organizations recommend cervical cancer screening for average-risk women aged 21-65 years. For average-risk women aged >65 years, routine screening may be discontinued if "adequate" screening with negative results is documented. Screening is recommended after age 65 years for women who do not meet adequate prior screening criteria or are at special risk.

METHODS

Authors examined the most recent cervical cancer incidence data from two federal cancer surveillance programs for all women by age and race, corrected for hysterectomy status. The 2013 and 2015 National Health Interview Surveys were analyzed in 2016 to examine the proportion of women aged 41-70 years without a hysterectomy who reported that they never had a Pap test or that their most recent Pap test was >5 years ago (not recently screened).

RESULTS

The incidence rate for cervical cancer among older women, corrected for hysterectomy status, did not decline until age ≥85 years. The proportion not recently screened increased with age, from 12.1% for women aged 41-45 years to 18.4% for women aged 61-65 years.

CONCLUSIONS

Even among women within the recommended age range for routine screening, many are not up to date, and a substantial number of women approach the "stopping" age for cervical cancer screening without an adequate prior screening history. Efforts are needed to reach women who have not been adequately screened, including women aged >65 years, to prevent invasive cervical cancer cases and deaths among older women.

Health Service Accessibility and Risk in Cervical Cancer Prevention: Comparing Rural Versus Nonrural Residence in New Mexico

PURPOSE

Multiple intrapersonal and structural barriers, including geography, may prevent women from engaging in cervical cancer preventive care such as screening, diagnostic colposcopy, and excisional precancer treatment procedures. Geographic accessibility, stratified by rural and nonrural areas, to necessary services across the cervical cancer continuum of preventive care is largely unknown.

METHODS

Health care facility data for New Mexico (2010-2012) was provided by the New Mexico Human Papillomavirus Pap Registry (NMHPVPR), the first population-based statewide cervical cancer screening registry in the United States. Travel distance and time between the population-weighted census tract centroid to the nearest facility providing screening, diagnostic, and excisional treatment services were examined using proximity analysis by rural and nonrural census tracts. Mann-Whitney test (P < .05) was used to determine if differences were significant and Cohen's r to measure effect.

FINDINGS

Across all cervical cancer preventive health care services and years, women who resided in rural areas had a significantly greater geographic accessibility burden when compared to nonrural areas (4.4 km vs 2.5 km and 4.9 minutes vs 3.0 minutes for screening; 9.9 km vs 4.2 km and 10.4 minutes vs 4.9 minutes for colposcopy; and 14.8 km vs 6.6 km and 14.4 minutes vs 7.4 minutes for precancer treatment services, all P < .001).

CONCLUSION

Improvements in cervical cancer prevention should address the potential benefits of providing the full spectrum of screening, diagnostic and precancer treatment services within individual facilities. Accessibility, assessments distinguishing rural and nonrural areas are essential when monitoring and recommending changes to service infrastructures (eg, mobile versus brick and mortar).

Population-Based Incidence Rates of Cervical Intraepithelial Neoplasia in the Human Papillomavirus Vaccine Era

IMPORTANCE

A substantial effect of human papillomavirus (HPV) vaccines on reducing HPV-related cervical disease is essential before modifying clinical practice guidelines in partially vaccinated populations.

OBJECTIVE

To determine the population-based cervical intraepithelial neoplasia (CIN) trends when adjusting for changes in cervical screening practices that overlapped with HPV vaccination implementation.

DESIGN, SETTING, AND PARTICIPANTS

The New Mexico HPV Pap Registry, which captures population-based estimates of both cervical screening prevalence and CIN, was used to compute CIN trends from January 1, 2007, to December 31, 2014. Under New Mexico Administrative Code, the New Mexico HPV Pap Registry, a statewide public health surveillance program, receives mandatory reporting of all cervical screening (cytologic and HPV testing) and any cervical, vulvar, and vaginal histopathological findings for all women residing in New Mexico irrespective of outcome.

MAIN OUTCOME MEASURES

Prespecified outcome measures included low-grade CIN (grade 1 [CIN1]) and high-grade CIN (grade 2 [CIN2] and grade 3 [CIN3]).

RESULTS

From 2007 to 2014, a total of 13 520 CIN1, 4296 CIN2, and 2823 CIN3 lesions were diagnosed among female individuals 15 to 29 years old. After adjustment for changes in cervical screening across the period, reductions in the CIN incidence per 100 000 women screened were significant for all grades of CIN among female individuals 15 to 19 years old, dropping from 3468.3 to 1590.6 for CIN1 (annual percentage change [APC], -9.0; 95% CI, -12.0 to -5.8; P < .001), from 896.4 to 414.9 for CIN2 (APC, -10.5; 95% CI, -18.8 to -1.2; P = .03), and from 240.2 to 0 for CIN3 (APC, -41.3; 95% CI, -65.7 to 0.3; P = .05). Reductions in the CIN2 incidence were also significant for women 20 to 24 years old, dropping from 1027.7 to 627.1 (APC, -6.3; 95% CI, -10.9 to -1.4; P = .02).

CONCLUSIONS AND RELEVANCE

Population-level decreases in CIN among cohorts partially vaccinated for HPV may be considered when clinical practice guidelines for cervical cancer screening are reassessed. Evidence is rapidly growing to suggest that further increases in raising the age to start screening are imminent, one step toward integrating screening and vaccination.

Harms of cervical cancer screening in the United States and the Netherlands

We studied harms related to cervical cancer screening and management of screen-positive women in the United States (US) and the Netherlands. We utilized data from four US integrated health care systems (SEARCH), the US National Health Interview Survey, New Mexico state, the Netherlands national histopathology registry, and included studies on adverse health effects of cervical screening. We compared the number of Papanicolaou (Pap) smear tests, abnormal test results, punch biopsies, treatments, health problems (anxiety, pain, bleeding and discharge) and preterm births associated with excisional treatments. Results were age-standardized to the 2007 US population. Based on SEARCH, an estimated 36 million Pap tests were performed in 2007 for 91 million US women aged 21-65 years, leading to 2.3 million abnormal Pap tests, 1.5 million punch biopsies, 0.3 million treatments for precancerous lesions, 5 thousand preterm births and over 8 million health problems. Under the Netherlands screening practice, fewer Pap tests (58%), abnormal test results (64%), punch biopsies (75%), treatment procedures (40%), preterm births (60%) and health problems (63%) would have occurred. The SEARCH data did not differ much from other US data for 2007 or from more recent data up to 2013. Thus compared to the less intensive screening practice in the Netherlands, US practice of cervical cancer screening may have resulted in two- to threefold higher harms, while the effects on cervical cancer incidence and mortality are similar. The results are also of high relevance in making recommendations for HPV screening. Systematic collection of harms data is needed for monitoring and for better incorporation of harms in making screening recommendations.

Cervical cancer screening in Switzerland: cross-sectional trends (1992-2012) in social inequalities

Background: Incidence and mortality of cervical cancer declined thanks to Pap smear screening. However cervical cancer screening (CCS) inequalities are documented, including in high income countries. This population-based study aims to assess the importance and 20-year trends of CCS inequalities in Switzerland, where healthcare costs and medical coverage are among the highest in the world. Methods: We analyzed data from five waves of the population-based Swiss Health Interview Survey (SHIS) covering the period 1992–2012. Multivariable Poisson regression were used to estimate weighted prevalence ratios (PR) of CCS and 95% Confidence Intervals (CI) adjusting for socio-economic, socio-demographic characteristics, family status, health status, and use of healthcare. Results: The study included 32’651 women aged between 20 and 70 years old. Between 1992 and 2012, rates of CCS over the past 3 years fluctuated between 71.7 and 79.6% (adjusted P < 0.001). Lower CCS was observed among women with low education, low income, those having limited emotional support, who were non-Swiss, single, older, living in non-metropolitan area or in the French-speaking region, overweight. Over the analyzed period, differences in CCS across age groups diminished while rates among women who visited a GP over the previous year, versus those who did not, increased. Conclusions : While important changes occurred in screening recommendations and in social circumstances of the targeted population, CCS rates remained fairly stable in Switzerland between 1992 and 2012. At the same time, inequalities in CCS persisted over that period.

Examining the Cervical Screening Behaviour of Women Aged 50 or above and Its Predicting Factors: A Population-Based Survey

Under-screening may increase the risk of cervical cancer in middle-aged women. This study aimed to investigate cervical cancer screening behaviour and its predictors among women aged 50 years or above. A population-based sample of 959 women was recruited by telephone from domestic households in Hong Kong, using random methods, and a structured questionnaire developed to survey participants. Multivariable logistic regressions were performed to examine the factors independently associated with cervical screening behaviour. Nearly half the sample (48%) had never had a cervical smear test. Multivariable analyses showed that age, educational level, marital status, family history of cancer, smoking status, use of complementary therapy, recommendation from health professionals, and believing that regular visits to a doctor or a Chinese herbalist were good for their health were predictors of cervical screening behaviour. Misconceptions concerned with menopause may reduce women's perceived susceptibility to cervical cancer, especially if they are 50 or above, and exert a negative effect on their screening behaviour. Healthcare professionals should actively approach these high-risk groups-older unmarried women, smokers, those less educated and who are generally not much concerned with their health.

Similar Risk Patterns After Cervical Screening in Two Large U.S. Populations: Implications for Clinical Guidelines

OBJECTIVE

To compare the risks of histologic high-grade cervical intraepithelial neoplasia (CIN) or worse after different cervical cancer screening test results between two of the largest U.S. clinical practice research data sets.

METHODS

The New Mexico Human Papillomavirus (HPV) Pap Registry is a statewide registry representing a diverse population experiencing varied clinical practice delivery. Kaiser Permanente Northern California is a large integrated health care delivery system practicing routine HPV cotesting since 2003. In this retrospective cohort study, a logistic-Weibull survival model was used to estimate and compare the cumulative 3- and 5-year risks of histologic CIN 3 or worse among women aged 21-64 years screened in 2007-2011 in the New Mexico HPV Pap Registry and 2003-2013 in Kaiser Permanente Northern California. Results were stratified by age and baseline screening result: negative cytology, atypical squamous cells of undetermined significance (ASC-US) (with or without HPV triage), low-grade squamous intraepithelial lesion, and high-grade squamous intraepithelial lesion.

RESULTS

There were 453,618 women in the New Mexico HPV Pap Registry and 1,307,528 women at Kaiser Permanente Northern California. The 5-year CIN 3 or worse risks were similar within screening results across populations: cytology negative (0.52% and 0.30%, respectively, P<.001), HPV-negative and ASC-US (0.72% and 0.49%, respectively, P=.5), ASC-US (3.4% and 3.4%, respectively, P=.8), HPV-positive and ASC-US (7.7% and 7.1%, respectively, P=.3), low-grade squamous intraepithelial lesion (6.5% and 5.4%, respectively, P=.009), and high-grade squamous intraepithelial lesion (53.1% and 50.4%, respectively, P=.2). Cervical intraepithelial neoplasia grade 2 or worse risks and 3-year risks had similar trends across populations. Age-stratified analyses showed more variability, especially among women aged younger than 30 years, but patterns of risk stratification were comparable.

CONCLUSION

Current U.S. cervical screening and management recommendations are based on comparative risks of histologic high-grade CIN after screening test results. The similar results from these two large cohorts from different real-life clinical practice settings support risk-based management thresholds across U.S. clinical populations and practice settings.

Trends in cervical cancer incidence in younger US women from 2000 to 2013

OBJECTIVE

This study aimed to assess the temporal trends in invasive cervical cancer (ICC) incidence rates among 21-25year-olds. US guidelines no longer recommend screening prior to age 21, and concerns have been raised that delayed screening initiation may increase ICC incidence among young women.

METHODS

This study utilized ICC incidence data from 18 US population-based cancer registries in SEER from 2000 to 2013 and Pap test prevalence data from the Behavioral Risk Factor Surveillance System from 1996 to 2012. Trends were evaluated with annual percent changes (APCs) using Joinpoint regression.

RESULTS

The prevalence of never having a Pap test before age 21 increased from 22.0% in 1996-2004 to 38.3% in 2006-2012 (APC=+5.48, 95%CI=+4.20, +7.50). Despite this decline in screening, ICC incidence among 21-23year olds significantly declined between 2000 and 13 (APC=-5.36, 95%CI=-7.83,-2.82), particularly from 2006 to 2013 (APC=-9.70, 95%CI=-15.79, -3.17). ICC incidence remained constant among 24-25year olds (APC=+0.45, 95%CI=-2.00, 2.97). Compared to women born in 1978-1985, women born in 1986-1991 had a higher prevalence of never receiving a Pap test prior to 21 (35.4% vs. 22.1%, p<0.001), but a lower ICC incidence at 21-23 (0.98 vs. 1.55 per 100,000, p<0.001).

CONCLUSION

While US females born in 1986-1991 were less likely to receive a Pap test before age 21, diagnoses of ICC in the early 20s were rare and lower than for those born in earlier years. This provides reassurance that the updated guidelines to delay screening until 21 has not resulted in a population-level increase in ICC rates among young women.

Prevalence of Primary HPV in Djibouti: Feasibility of Screening for Early Diagnosis of Squamous Intraepithelial Lesions

OBJECTIVE

In many African Sub-Saharan countries, human papilloma virus (HPV) prevalence data are not available. The current study estimated the prevalence of HPV virus in the female population of Djibouti.

METHODS

Approximately 1000 asymptomatic women 16 to 64 years old were enrolled from 3 of the main health structures of Djibouti in 2014 and 2015; 998 cervical samples were tested for HPV-DNA of high risk types, 499 during the first year, and 499 during the second. Positive samples were typed with an HPV genotyping kit.

RESULTS

The women were an average age of 38.8 years (SD, 10.2); 54 women tested positive for HPV (prevalence rate, 5.4% [95% confidence interval, 4.0-6.8]). The highest prevalence was observed among the women younger than 35 years. HPV66 was the most prevalent (15.4% of the infections), followed by HPV31 and HPV52 (10.8% both) and HPV16 (9.2%). All 54 women who tested HPV-positive underwent a Pap test, which was positive in 8 cases (14.8%): 2 high-grade squamous intraepithelial lesion (HSIL) and 6 low-grade (LSIL).

CONCLUSIONS

The HPV prevalence shows a curve by age similar to that of other African countries. The proportion of HPV16 is among the lowest ever seen in similar studies. The findings suggest to Djibouti the choice of a strategy of screening that includes forms of cytological triage, thus limiting recourse to colposcopy.

Comparative effectiveness of two outreach strategies for cervical cancer screening

OBJECTIVE

Test-specific reminder letters can improve cancer screening adherence. Little is known about the effectiveness of a reminder system that targets the whole person by including multiple screening recommendations per letter.

METHODS

We compared the effectiveness of a Pap-specific reminder letter sent 27months after a woman's last Pap, to a reminder letter that included up to seven preventive service recommendations sent before a woman's birthday ("birthday letter") on Pap smear adherence from a natural experiment occurring in routine clinical care. Participants included 82,016 women from Washington State who received 72,615 Pap-specific letters between 2003 and 2007 and 100,218 birthday letters between 2009 and 2012. We defined adherence as having a Pap test within a six month window around the Pap test due date. Using logistic regression, we calculated adjusted odds ratios (OR) for adherence with 95% confidence intervals (CI) following the birthday letter with 1-2 recommendations, 3-5 recommendations, and 6-7 recommendations compared to the Pap-specific letter. All analyses were stratified by whether a woman was up-to-date or overdue for screening at the time she received a letter.

RESULTS

Adjusted ORs showed reduced adherence following the birthday letter compared with the Pap-specific letter for up-to-date women whether the letter had 1-2 recommendations (OR=0.37, 95%CI=0.36-0.39), 3-5 recommendations (OR=0.44, 95%CI=0.42-0.45), or 6-7 recommendations (OR=0.36, 95%CI=0.32-0.40). We noted no difference in Pap-test adherence between letter types for overdue women.

CONCLUSIONS

In conclusion, for women regularly adherent to screening, an annual birthday letter containing reminders for multiple preventive services was less effective at promoting cervical cancer screening compared with a Pap-specific letter.

The potential harms of primary human papillomavirus screening in over-screened women: a microsimulation study

BACKGROUND

It is well acknowledged that HPV testing should not be performed at young age and at short intervals. Cytological screening practices have shown that over-screening, i.e., from a younger age and at shorter intervals than recommended, is hard to avoid. We quantified the consequences of a switch to primary HPV screening for over-screened women, taking into account its higher sensitivity but lower specificity than cytology.

METHODS

The health effects of using the HPV test instead of cytology as the primary screening method were determined with the MISCAN-Cervix model. We varied the age women start screening and the interval between screens. In the sensitivity analyses, we varied the background risk of cervical cancer, the HPV prevalence, the discount rate, the triage strategy after cytology, and the test characteristics of both cytology and the HPV test.

RESULTS

For women screened 5 yearly from age 30, 32 extra deaths per 100,000 simulated women were prevented when switching from primary cytology to primary HPV testing. For annual screening from age 20, such a switch resulted in 6 extra deaths prevented. It was associated with 9,044 more positive primary screens in the former scenario versus 76,480 in the latter. Under all conditions, for women screened annually, switching to HPV screening resulted in a net loss of quality-adjusted life years.

CONCLUSION

For over-screened women, the harms associated with a lower test specificity outweigh the life years gained when switching from primary cytology to primary HPV testing. The extent of over-screening should be considered when deciding on inclusion of primary HPV screening in cervical cancer screening guidelines.

Use of claims data to estimate annual cervical cancer screening percentages in Portland metropolitan area, Oregon

BACKGROUND

Human papillomavirus (HPV) vaccine should reduce cervical dysplasia before cervical cancer. However, dysplasia diagnosis is screening-dependent. Accurate screening estimates are needed.

PURPOSE

To estimate the percentage of women in a geographic population that has had cervical cancer screening.

METHODS

We analyzed claims data for (Papanicolau) Pap tests from 2008-2012 to estimate the percentage of insured women aged 18-39 years screened. We estimated screening in uninsured women by dividing the percentage of insured Behavioral Risk Factor Surveillance Survey respondents reporting previous-year testing by the percentage of uninsured respondents reporting previous-year testing, and multiplying this ratio by claims-based estimates of insured women with previous-year screening. We calculated a simple weighted average of the two estimates to estimate overall screening percentage. We estimated credible intervals using Monte-Carlo simulations.

RESULTS

During 2008-2012, an annual average of 29.6% of women aged 18-39 years were screened. Screening increased from 2008 to 2009 in all age groups. During 2009-2012, the screening percentages decreased for all groups, but declined most in women aged 18-20 years, from 21.5% to 5.4%. Within age groups, compared to 2009, credible intervals did not overlap during 2011 (except age group 21-29 years) and 2012, and credible intervals in the 18-20 year group did not overlap with older groups in any year.

CONCLUSIONS

This introduces a novel method to estimate population-level cervical cancer screening. Overall, percentage of women screened in Portland, Oregon fell following changes in screening recommendations released in 2009 and later modified in 2012.

Risk Stratification Using Human Papillomavirus Testing among Women with Equivocally Abnormal Cytology: Results from a State-Wide Surveillance Program

BACKGROUND

Clinical guidelines for cervical cancer screening have incorporated comparative risks of cervical intraepithelial neoplasia grade 3 or cancer (CIN3(+)) for various screening outcomes to determine management. Few cohorts are large enough to distinguish CIN3(+) risks among women with minor abnormalities versus negative cytology because of low incidence. The New Mexico Human Papillomavirus (HPV) Pap Registry offers a unique opportunity to evaluate cervical cancer screening in a diverse population across a broad-spectrum of health service delivery.

METHODS

Kaplan-Meier and logistic-Weibull survival models were used to estimate cumulative risks of CIN3(+) among women ages 21 to 64 who were screened in New Mexico between 2007 and 2011 with negative, equivocal or mildly abnormal cytology, that is, atypical squamous cells of undetermined significance (ASC-US; with or without HPV triage), or low-grade squamous intraepithelial lesions (LSIL).

RESULTS

We identified 452,045 women meeting the selection criteria. The 3-year CIN3(+) risks for women with negative, ASC-US, and LSIL cytology were 0.30%, 2.6%, and 5.2%, respectively. HPV triage of ASC-US stratified 3-year CIN3(+) risks were 0.72% for HPV-negative and 7.7% for HPV-positive. Risks tended to decline after age 30 for all screening results.

CONCLUSIONS

In this state-wide population-based cohort, cytology and HPV triage of ASC-US stratified women's CIN3(+) risk into similar patterns observed previously, suggesting the validity of screening guidelines for diverse populations in the United States. Absolute risk estimates should be compared across other large populations.

IMPACT

Strategies for HPV triage of ASC-US derived from clinical trials are upheld in large clinical practice settings and across diverse screening populations in the United States.

Comparison of the performance of Anyplex II HPV HR, the Cobas 4800 human papillomavirus test and Hybrid Capture 2

BACKGROUND

Anyplex II HPV HR (Anyplex_HR; Seegene, Seoul, Korea) is a new multiplex real-time polymerase chain reaction assay for screening cervical cancer, and it is designed to detect 14 high-risk human papillomaviruses along with all the genotype information in a single tube. The aim of this study was to evaluate the performance of the Anyplex_HR in comparison to that of the Cobas 4800 HPV (Cobas_4800; Roche Molecular Diagnostics, Pleasanton, CA, USA) and the Hybrid capture 2 (HC2; Qiagen GmbH, Hilden, Germany).

METHODS

The performance of the Anyplex_HR for high-risk human papillomavirus genotype detection was prospectively evaluated against that of the HC2 and the Cobas_4800 at the National Cancer Center using 400 cervical samples. All discrepant samples were confirmed by polymerase chain reaction with type-specific primers followed by sequencing.

RESULTS

The overall agreement and kappa value of the Anyplex_HR with the Cobas_4800 were 98.0% and 0.96, respectively. The level of agreement between the two assays and the corresponding kappa values for human papillomavirus16, human papillomavirus18 and other high-risk human papillomaviruses were 99.5%, 99.8% and 98.8%, and 0.98, 0.96 and 0.97, respectively. The agreement and kappa value of the HC2 with the Cobas_4800 were 95.3% and 0.91. The human papillomavirus positivity of the Anyplex_HR and the Cobas_4800 in low-grade squamous intraepithelial lesion/high-grade squamous intraepithelial lesion samples demonstrated 100% concordance. Both the Anyplex_HR and the Cobas_4800 showed excellent results in the precision test.

CONCLUSIONS

The Anyplex_HR is comparable with the Cobas_4800 and the HC2 for human papillomavirus DNA testing, and it may prove more useful for follow-up testing and patient management by providing genotyping information additional to human papillomavirus16 and human papillomavirus18.

Inefficiencies and High-Value Improvements in U.S. Cervical Cancer Screening Practice: A Cost-Effectiveness Analysis

BACKGROUND

Studies suggest that cervical cancer screening practice in the United States is inefficient. The cost and health implications of nonadherence in the screening process compared with recommended guidelines are uncertain.

OBJECTIVE

To estimate the benefits, costs, and cost-effectiveness of current cervical cancer screening practice and assess the value of screening improvements.

DESIGN

Model-based cost-effectiveness analysis.

DATA SOURCES

New Mexico HPV Pap Registry; medical literature.

TARGET POPULATION

Cohort of women eligible for routine screening.

TIME HORIZON

Lifetime.

PERSPECTIVE

Societal.

INTERVENTION

Current cervical cancer screening practice; improved adherence to guidelines-based screening interval, triage testing, diagnostic referrals, and precancer treatment referrals.

OUTCOME MEASURES

Reductions in lifetime cervical cancer risk, quality-adjusted life-years (QALYs), lifetime costs, incremental cost-effectiveness ratios, and incremental net monetary benefits (INMBs).

RESULTS OF BASE-CASE ANALYSIS

Current screening practice was associated with lower health benefit and was not cost-effective relative to guidelines-based strategies. Improvements in the screening process were associated with higher QALYs and small changes in costs. Perfect adherence to screening every 3 years with cytologic testing and adherence to colposcopy/biopsy referrals were associated with the highest INMBs ($759 and $741, respectively, at a willingness-to-pay threshold of $100,000 per QALY gained); together, the INMB increased to $1645.

RESULTS OF SENSITIVITY ANALYSIS

Current screening practice was inefficient in 100% of simulations. The rank ordering of screening improvements according to INMBs was stable over a range of screening inputs and willingness-to-pay thresholds.

LIMITATION

The effect of human papillomavirus vaccination was not considered.

CONCLUSIONS

The added health benefit of improving adherence to guidelines, especially the 3-year interval for cytologic screening and diagnostic follow-up, may justify additional investments in interventions to improve U.S. cervical cancer screening practice.

PRIMARY FUNDING SOURCE

U.S. National Cancer Institute.

Global epidemiology of hysterectomy: possible impact on gynecological cancer rates

Despite the fact that hysterectomy is the most common surgical procedure worldwide in gynecology, national reporting of the incidence rate of gynecological cancers rarely removes the proportion no longer at risk of the disease from the population-at-risk-denominator (ie, women who have had a hysterectomy). The incidence rate of gynecological cancers is thus likely underestimated. Because hysterectomy, as well as oophorectomy, incidence varies across countries, age, and over time, meaningful comparison of gynecological cancer incidence rates may be compromised. Without accurate estimates of gynecological cancer incidence rates, performed via removing the proportion of hysterectomized or oophorectomized women from the population-at-risk-denominator, the impact of prevention strategies may be masked or misinterpreted. Furthermore, because national cervical cancer screening guidelines are at least in part based on the national reporting of cervical cancer incidence, it is important that the incidence rate reflects the true population at risk.

Population-based trends in high-grade cervical lesions in the early human papillomavirus vaccine era in the United States

BACKGROUND

Cervical intraepithelial neoplasia grade 2, 3, and adenocarcinoma in situ (CIN2+) lesions can be monitored as early indicators of human papillomavirus (HPV) vaccine impact. Changes to screening utilization will affect observed reductions in CIN2+ rates and complicate the interpretation of vaccine impact.

METHODS

From 2008 to 2012, 9119 cases of CIN2+ among 18- to 39-year-old residents of catchment areas in California, Connecticut, New York, and Oregon were reported to the HPV-IMPACT Project, a sentinel system for monitoring the population impact of HPV vaccine. Age-stratified CIN2+ incidence rates were calculated for each catchment. Annual cervical screening was estimated for California, New York, and Oregon catchments with administrative and survey data. The Cochran-Armitage test was used to examine trends.

RESULTS

From 2008 to 2012, the incidence of CIN2+ significantly decreased among 18- to 20-year-olds (California, from 94 to 5 per 100,000 women; Connecticut, from 450 to 57 per 100,000 women; New York, from 299 to 43 per 100,000 women; and Oregon, from 202 to 37 per 100,000 women; Ptrend  < .0001) and among 21- to 29-year-olds in Connecticut (from 762 to 589 per 100,000 women) and New York (from 770 to 465 per 100,000 women; Ptrend  < .001); rates did not differ among 30- to 39-year-olds. During the same period, screening rates also declined, with the largest decreases among 18- to 20-year-olds (from 67% in Oregon to 88% in California) and with smaller declines among 21- to 29-year-olds (13%-27%) and 30- to 39-year-olds (3%-21%).

CONCLUSIONS

The declines in CIN2+ detection in young women were likely due to reduced screening but could also reflect the impact of vaccination. These data illustrate challenges in interpreting CIN2+ ecologic trends in the new era of cervical cancer prevention and emphasize the importance of information such as HPV types detected in lesions to assess the impact of HPV vaccine on cervical precancers.

Cervical cancer screening and follow-up in 4 geographically diverse US health care systems, 1998 through 2007

BACKGROUND

Cervical cancer screening and follow-up guidelines have changed considerably in recent years, but to the authors' knowledge few published reports exist to estimate the impact of these changes in community-based settings. The authors examined the patterns and results of cervical cancer testing and follow-up over a decade in 4 geographically diverse US health care systems to inform the future evaluation of changes resulting from increased uptake of the human papillomavirus (HPV) vaccination.

METHODS

The authors studied women aged 21 to 65 years who were members of one of these health systems at any time between 1998 and 2007. Data were collected and standardized across sites, based on receipt of Papanicolaou (Pap) and HPV tests, HPV vaccination, cervical biopsies, and treatment of cervical dysplasia. Annual rates (per 1000 person-years) of Pap testing, HPV testing, and cervical biopsy and treatment procedures were calculated. Screening intervals and trends in the results of screening Pap tests and cervical biopsies also were examined.

RESULTS

Pap testing rates decreased (from 483 per 1000 person-years in 2000 to 412 per 1000 person-years in 2007) and HPV testing rates increased over the study period. Screening frequency varied across health care systems, and many women continued to receive annual testing. All 4 sites moved to less frequent screening over the study period without marked changes in the overall use of cervical biopsy or treatment.

CONCLUSIONS

Despite differences over time and across health plans in rates of cervical cancer testing and follow-up cervical procedures, the authors found no notable differences in Pap test results, diagnostic or treatment procedure rates, or pathological outcomes. This finding suggests that the longer screening intervals did not lead to more procedures or more cancer diagnoses.

Human papillomavirus testing 2007-2012: co-testing and triage utilization and impact on subsequent clinical management

In the United States, high-risk human papillomavirus (HPV) testing is recommended for women with atypical squamous cells of unknown significance (ASC-US) cytology, and co-testing with cytology and HPV is a recommended option for screening women aged ≥ 30 years. No population-based data are available to examine utilization of HPV testing in the United States. Using the New Mexico HPV Pap Registry data resource, we describe population trends (2007-2012) in utilization and positivity rates for HPV testing as a routine co-testing screening procedure and for triage of ASC-US and other cytologic outcomes. For women aged 30-65 years co-testing increased from 5.2% in 2007 to 19.1% in 2012 (p < 0.001). Overall 82% of women with ASC-US cytology who did not receive co-testing also had an HPV test. HPV positivity was age and cytology result dependent but did not show time trends. For women with negative cytology, 64% received an additional screening test within 3 years if no co-test was done or if it was positive, but this was reduced to 47% with a negative co-test. Reflex HPV testing for ASC-US cytology is well established and occurs in most women. Evidence for reflex testing is also observed following other abnormal cytology outcomes. Co-testing in women aged 30-65 years has more than tripled from 2007 to 2012, but was still only used in 19.1% of women aged 30-65 years attending for screening in 2012. Women receiving co-testing had longer repeat screening intervals, but rescreening within 3 years is still very common even with co-testing.

Concurrence of multiple human papillomavirus infections in a large US population-based cohort

We examined the concurrence of multiple human papillomavirus (HPV) infections in 47,617 women who underwent cervical screening in New Mexico between December 2007 and April 2009 using the LINEAR ARRAY HPV Genotyping Test (Roche Diagnostics, Indianapolis, Indiana), which detects 37 different types of HPV. Our primary goal was to examine the distributions of multiple HPV types with a special interest in negative interactions, which could signal the possibility of type replacement associated with a common niche if some HPV types were prevented by vaccination. Multiple infections were found to be more common than expected under independence, but this could largely be accounted for by a woman-specific latent heterogeneity parameter which was found to be dependent on age and cytological grade. While multiple infections were more common in young women and in those with abnormal cytology, greater heterogeneity was seen in older women and in those with normal cytology, possibly reflecting greater variability in exposure due to current or past HPV exposure or due to heterogeneity in related HPV reactivation or in immune responses to HPV infection or persistence. A negative interaction was found between HPV 16 and several other HPV types for women with abnormal cytology but not for those with normal cytology, suggesting that type replacement in women vaccinated against HPV 16 is unlikely to be an issue for the general population.

Human papillomavirus genotype-specific prevalence across the continuum of cervical neoplasia and cancer

BACKGROUND

The New Mexico HPV Pap Registry was established to measure the impact of cervical cancer prevention strategies in the United States. Before widespread human papillomavirus (HPV) vaccine implementation, we established the baseline prevalence for a broad spectrum of HPV genotypes across the continuum of cervical intraepithelial neoplasia (CIN) and cancer.

METHODS

A population-based sample of 6,272 tissue specimens was tested for 37 HPV genotypes. The number of specimens tested within each diagnostic category was: 541 negative, 1,411 CIN grade 1 (CIN1), 2,226 CIN grade 2 (CIN2), and 2,094 CIN grade 3 (CIN3) or greater. Age-specific HPV prevalence was estimated within categories for HPV genotypes targeted by HPV vaccines.

RESULTS

The combined prevalence of HPV genotypes included in the quadrivalent and nonavalent vaccines increased from 15.3% and 29.3% in CIN1 to 58.4% and 83.7% in CIN3, respectively. Prevalence of HPV types included in both vaccines tended to decrease with increasing age for CIN1, CIN2, CIN3, and squamous cell carcinoma (SCC), most notably for CIN3 and SCC. The six most common HPV types in descending order of prevalence were HPV-16, -31, -52, -58, -33, and -39 for CIN3 and HPV-16, -18, -31, -45, -52, and -33 for invasive cancers.

CONCLUSIONS

Health economic modeling of HPV vaccine impact should consider age-specific differences in HPV prevalence.

IMPACT

Population-based HPV prevalence in CIN is not well described, but is requisite for longitudinal assessment of vaccine impact and to understand the effectiveness and performance of various cervical screening strategies in vaccinated and unvaccinated women.

Intent to participate in future cervical cancer screenings is lower when satisfaction with the decision to be vaccinated is neutral

BACKGROUND

HPV vaccination programs have adversely affected participation in future cervical cancer screening. The purpose of this study is to determine the influence of decision satisfaction with accepting/rejecting the HPV vaccine, as well as traditional clinical factors, on the intent to participate in future screening.

METHODS AND FINDINGS

From January 2011 through August 2012 women 18-26 years old presenting for health care in an urban college student health and wellness clinic in the US Midwest were asked to complete a descriptive and medical history survey including a six element decisional satisfaction survey scored on 5-point Likert scales, where the intent to participate in future cervical cancer screening was measured. Of the 568 women who completed the decisional satisfaction survey, 17% of those <21 years and 7% ≥ 21 years indicated no intent to participate in future cervical cancer screenings. Among women of current screening age, the univariate risk factors of race/ethnicity, contraceptive use, number of lifetime sexual partners, and receipt of HPV vaccine were not predictors of intent for future cervical cancer screening. Instead, only a history of a prior Pap test was a significant positive predictor and only a decisional satisfaction of 'neutral' (Likert score = 3) for any of the four decisional satisfaction elements was a significant negative predictor. For the decisional satisfaction element "best for me personally", there was a 78% decreased likelihood of intending to participate in future screening if the satisfaction was neutral rather than firm (aOR = 0.22, 95% CI: 0.05-0.91) and a 26 fold increased likelihood if she had had a prior Pap test (aOR = 26, 95% CI: 5-133).

CONCLUSIONS

HPV vaccination implementation programs must help women be the owner of their decision around HPV vaccination and understand the importance of future participation in cervical cancer screening.