Recommendations for cervical cancer prevention in Latin America and the Caribbean

High frequency of alpha7-HPV in Colombian Caribbean coast women: cervical cancer screening analysis

BACKGROUND

Cervical cancer (CC) is a significant global public health concern, particularly in developing countries such as Colombia. The main risk factor involves high-risk HPV types (HR-HPV) infection, coupled with population-specific variables. The Caribbean region in Colombia lacks research on HR-HPV-type frequencies. Therefore, this study aims to establish the prevalence of type-specific HR-HPV and its association with sociodemographic factors among women undergoing cervical cytology screening.

METHODS

A cross-sectional study involving voluntary women who provided informed consent and completed a questionnaire capturing sociodemographic, clinical, and sexual behavior information was conducted. All participants underwent cervical cytology and molecular analysis. Generic HPV detection employed three simultaneous PCRs (GP5+/6+, MY09/11, and PU1R/2 M), and positive samples were genotyped using the Optiplex HPV Genotyping kit. The analysis encompassed the 12 types of high-risk HPV (HR-HPV-16,-18,-31,-33,-35,-39,-45,-51,-52,-56,-58, and - 59). Frequencies were reported based on geographic subregions within the Córdoba department, and disparities were made between single and multiple infections. Sociodemographic and clinical variables were subjected to ordinal logistic regression, with statistical significance at a p-value < 0.05. The statistical analyses utilized STATA 14® and R-Core Team-software.

RESULTS

We included 450 women, mean age 40 (SD±11.44). PCR analysis revealed 43% HPV-positive (n=192). GP5+/6+ detected the most positives at 26% (n=119), followed by PU1R/2 M at 22% (n = 100) and MY09/11 at 15% (n=69). Multiple infections occurred in 87.3% (n=142), primarily 2 to 4 types (47.37%, n=90). Dominant types were HPV-18 (15.6%, n=61), HPV-16 (14.9%, n=58), HPV-31 (13.0%, n = 51), and HPV-45 (11.5%, n=45). Logistic regression identified age above 60 as a risk for concurrent multiple types (OR=6.10; 95% CI 1.18-31.63). Menopause was protective (OR=0.31; 95% CI 0.11-0.89).

CONCLUSIONS

Our study reveals a notable prevalence of multiple (2-4) high-risk HPV infections among adult women engaged in CC detection initiatives. Predominantly, α7 species constitute the prevalent HR-viral types, with the Medio Sinú subregion showing elevated prevalence. Menopausal status confers protection against diverse HR-HPV infections. Nevertheless, advancing age, particularly beyond 60 years, is linked to an increased susceptibility to simultaneous infections by multiple HPV-types.

Awareness and Knowledge of HPV, HPV Vaccination, and Cervical Cancer among an Indigenous Caribbean Community

Caribbean women experience a cervical cancer incidence rate that is three times higher than that among their North American counterparts. In this study, we performed a needs assessment of the knowledge and awareness of HPV, HPV vaccination, and cervical cancer and receipt of cervical cancer screening among an indigenous Caribbean community. We purposively recruited individuals aged ≥18 from a community health care clinic (n = 58) to complete a 57-item structured interview including items on demographics, cancer history, knowledge and awareness of HPV, HPV vaccines, cervical cancer, and cervical cancer screening. Participants' mean age was 47.1 years (SD: 14.4). Most were female (74.1%), were married/partnered (51.7%), had primary education (63.8%), and identified as Kalinago (72.4%). Whereas 79.5% had heard of cervical cancer, few had heard of HPV (19.6%) or the HPV vaccine (21.8%). Among those who knew someone with cancer, 90.9% had heard of the HPV vaccine, compared with only 9.1% of those who did not know anyone with cancer (p = 0.02). Access to HPV vaccination is an immediate, cost-effective cancer prevention priority for reducing the disproportionate burden of HPV-related cancers, particularly cervical cancer, in the Caribbean. We recommend culturally targeted education interventions to improve knowledge about HPV vaccination and the link between HPV and cervical cancer.

Multi-task network for automated analysis of high-resolution endomicroscopy images to detect cervical precancer and cancer

Cervical cancer is a public health emergency in low- and middle-income countries where resource limitations hamper standard-of-care prevention strategies. The high-resolution endomicroscope (HRME) is a low-cost, point-of-care device with which care providers can image the nuclear morphology of cervical lesions. Here, we propose a deep learning framework to diagnose cervical intraepithelial neoplasia grade 2 or more severe from HRME images. The proposed multi-task convolutional neural network uses nuclear segmentation to learn a diagnostically relevant representation. Nuclear segmentation was trained via proxy labels to circumvent the need for expensive, manually annotated nuclear masks. A dataset of images from over 1600 patients was used to train, validate, and test our algorithm; data from 20% of patients were reserved for testing. An external evaluation set with images from 508 patients was used to further validate our findings. The proposed method consistently outperformed other state-of-the art architectures achieving a test per patient area under the receiver operating characteristic curve (AUC-ROC) of 0.87. Performance was comparable to expert colposcopy with a test sensitivity and specificity of 0.94 (p = 0.3) and 0.58 (p = 1.0), respectively. Patients with recurrent human papillomavirus (HPV) infections are at a higher risk of developing cervical cancer. Thus, we sought to incorporate HPV DNA test results as a feature to inform prediction. We found that incorporating patient HPV status improved test specificity to 0.71 at a sensitivity of 0.94.

Barriers and facilitators to the HPV vaccine among mothers of adolescent girls: a qualitative study conducted in Trinidad and Tobago

Cervical cancer is a major public health problem in Latin America and the Caribbean and the human papillomavirus (HPV) vaccine may prevent thousands of cases of cervical cancer. The current study explored barriers and facilitators that affected the acceptance of the HPV vaccine by mothers of adolescents. This paper explores the qualitative findings from a larger mixed-methods study. Six focus groups were conducted (N = 33) throughout Trinidad and Tobago with mothers of adolescent girls. Three major themes emerged: a) cervical cancer and vaccine knowledge, b) barriers to uptake, and c) rephrasing the vaccine strategy. Data indicated that no widespread strategies to educate the population about the vaccine had occurred. Barriers to uptake of the vaccine were related to a lack of information on the efficacy and safety of HPV vaccines. Parents were unaware that the HPV caused cervical cancer. It is recommended that physicians and other health professionals be used to deliver targeted messages to parents and adolescents to improve uptake of the vaccine.

Prevalence, genotype distribution and risk factors of cervical HPV infection in Yangqu, China: a population-based survey of 10086 women

Human papillomavirus(HPV) infection is a necessary factor for the development of cervical cancer. The HPV vaccine is currently available, but there is still a lack of large-scale research on the distribution and risk factors of HPV. The aim of this study is to investigate the genotype distribution and risk factors of HPV infection in Yangqu which is located in North China. This study enrolled 10086 women aged <65 years from Yangqu County. HPV genotypes were identified via standard HPV DNA testing. The overall prevalence of HPV infection was 8.92%. The prevalence of high-risk HPV types was 8.80%, and it was 0.38% for low-risk HPV types. Single genotype infection accounted for 67.91% in HPV-positive cases. The most common HPV genotypes were HPV-16, -52, and -58. HPV-18 was only the 11th most common type in HPV-positive cases. Women ≥50 years of age had the highest prevalence rate of HPV, and women <30 years had the lowest prevalence rate. The distribution of HPV genotypes also varied among the three age groups: <30, 30-49, and ≥50 years. The risk factors that contributed to the rate of HPV infection included low educational level, low income, smoking, age at first sexual encounter <23 years old, and number of births ≥3 times. This large routine clinical practice report of HPV prevalence and genotype distribution revealed the characteristics of HPV infection-type distributions in Shanxi Province, which should be considered in formulating comprehensive prevention strategies including vaccination for cervical cancer in China.

Factors associated with high-risk human papillomavirus infection and high-grade cervical neoplasia: A population-based study in Paraguay

BACKGROUND

Cervical cancer (CC) is one of the leading causes of cancer mortality among women from Paraguay, with high incidence and mortality rates (31.2 and 16 per 100 000 women, respectively). Although the risk factors associated with high-risk human papillomavirus (hrHPV) infection and preneoplastic cervical lesions are widely studied, population-based characteristics of particular settings may influence the feasibility of HPV-based CC screening implementation. This study aimed to explore factors associated with hrHPV infection and high-grade cervical neoplasia in hrHPV-positive (hrHPV+) women from Paraguay.

METHODS

A total of 5677 women aged 30-64 years from the Central Department of Paraguay were screened with HPV test (Hybrid Capture 2) and Pap smear. Sociodemographic and risk factor interviews were conducted. hrHPV+ women were referred to colposcopy and women with an abnormal colposcopy had a biopsy taken. The outcomes recorded were the hrHPV status and the presence of high-grade cervical intraepithelial neoplasia or worse (CIN2+) among hrHPV+ women. Associations were investigated using multivariate logistic regressions.

RESULTS

hrHPV prevalence was 13.8% (95%CI 13.0-14.8). This value decreased with the age of women (p-trend<0.001) and increased with the lifetime number of sexual partners (p-trend<0.001) and number of previous female partners of their current male partner if women had had one lifetime sexual partner (p-trend<0.001), increasing from 3.06 (95%CI 0.073-20.9) if partners had had one previous female partner to 9.19 (95%CI 2.36-61.1) if they had had eight or more. In hrHPV+ women, CIN2+ prevalence was 10.7% (95%CI 8.58-13.2) and increased with time since the last Pap smear (p-trend<0.001) and with the increasing number of pregnancies (p-trend = 0.05).

CONCLUSION

In these settings, the sexual behavior of women and their male partners is associated with hrHPV infection. In hrHPV+ women, underscreening practices and multiple pregnancies are associated with CIN2+. This knowledge can contribute to public health policies for CC prevention and control in Paraguay.

Predictors and acceptability of human papilloma virus vaccine uptake among senior secondary school students in Ile-Ife

Introduction: Cervical cancer is the second most common cancer in women worldwide and in Nigeria. Human papilloma virus (HPV), has been implicated as the causative agent of cervical cancer. The fact that HPV vaccination can prevent the occurrence of this deadly cancer is well established. Though the vaccine has been licensed in Nigeria since 2009 with widespread availability, it is yet to be included in National immunization program in Nigeria. This study aimed to assess the predictors and acceptability of the HPV vaccine among senior secondary girls in Ile-Ife. Methods: This descriptive cross-sectional study recruited 400 students randomly selected from various secondary schools in Ife central-local government. The data was collected with the use of a pre-tested interviewer-administered questionnaire on knowledge, attitude, and acceptability of cervical cancer, HPV and HPV vaccine. Data were analyzed using descriptive and inferential statistics. Results: Most respondents (93.2%) had poor knowledge of cervical cancer, HPV and HPV vaccine. Attitude towards cervical cancer and HPV vaccine was good and the majority (74.5%) had high acceptability for the HPV vaccine. Only 2.8% of the respondents have been vaccinated. Predictors of acceptability of HPV vaccine were younger age group ((AOR) 4.05, CI = 2.30-5.45), good knowledge ((AOR = 2.50, CI = 2.31-6.83), mother' higher level of education (AOR = 1.55, CI = 2.62-4.58), perceived fatality of cervical cancer (AOR = 4.13, CI = 1.49 - 4.19) and perceived efficacy of the HPV vaccine (AOR = 1.57, CI = 0.49 - 3.18). Conclusions: The knowledge of secondary school girls in the study area on cervical cancer, HPV and HPV vaccine is poor though the HPV vaccine acceptability is high. The high acceptability of the vaccine in this study is a reflection of the willingness of this vulnerable group to learn more about the subject matter. There is the need to create school health programs that will focus on health educating the students on this preventable cancer and the available vaccine. Including HPV vaccine into National immunization program in Nigeria may also improve awareness of cervical cancer and the vaccine uptake.

Localizing Global Medicine: Challenges and Opportunities in Cervical Screening in an Indigenous Community in Ecuador

This participatory research study examines the tensions and opportunities in accessing allopathic medicine, or biomedicine, in the context of a cervical cancer screening program in a rural indigenous community of Northern Ecuador. Focusing on the influence of social networks, the article extends research on "re-appropriation" of biomedicine. It does so by recognizing two competing tensions expressed through social interactions: suspicion of allopathic medicine and the desire to maximize one's health. Semistructured individual interviews and focus groups were conducted with 28 women who had previously participated in a government-sponsored cervical screening program. From inductive thematic analysis, the article traces these women's active agency in navigating coherent paths of health. Despite drawing on social networks to overcome formidable challenges, the participants faced enduring system obstacles-the organizational effects of the networks of allopathic medicine. Such obstacles need to be understood to reconcile competing knowledge systems and improve health care access in underresourced communities.

Social and Cultural Barriers to Women's Participation in Pap Smear Screening Programs in Low- and Middle-Income Latin American and Caribbean Countries: An Integrative Review

PURPOSE

Pap smear screening programs have been ineffective in reducing cervical cancer mortality in most Latin American and Caribbean countries, in part due to low screening rates. The purpose of this review was to analyze recent studies to identify demographic, social, and cultural factors influencing women's participation in Pap screening programs in Latin America and the Caribbean.

DESIGN/METHOD

For this integrative review, cervical cancer screening in Latin America and the Caribbean was searched using PubMed, CINAHL, EMBASE, and PsycINFO databases. Findings/Results: Demographic barriers to screening were socioeconomic status, education, race/ethnicity, and geography. Social barriers included lack of uniformity in screening guidelines, lack of knowledge regarding cervical cancer, and lack of preventive culture. Cultural barriers were fear/embarrassment and gender roles.

CONCLUSIONS

There are multilevel barriers to Pap smear utilization among women in Latin America and the Caribbean.

IMPLICATIONS FOR PRACTICE

Findings highlight a need for health system engagement, promotion of preventive care, and community-generated educational programs and solutions.

Interventions that facilitate adherence to Pap smear exam: integrative review

RESUMO Objetivo: identificar produções científicas que apresentem intervenções relevantes para implementar o Programa de Prevenção do Câncer Cérvico-Uterino, aumentando a adesão à realização do exame. Método: revisão integrativa da literatura, realizada por busca on-line, nas bases de dados: LILACS, SciELO e Pubmed®, abrangendo artigos publicados de 2009 a 2014. Resultados: trinta e oito artigos compuseram a amostra final do estudo. Estes indicaram as seguintes intervenções: utilização de gerente de caso, contato telefônico, carta-convite, atividades educativas, divulgação na mídia, agentes de saúde da comunidade, parcerias, rastreamento de base populacional e múltiplas intervenções. Conclusão: as pesquisas concentram-se entre mulheres provenientes de países em desenvolvimento, e estas intervenções são eficazes no aumento da adesão e do conhecimento destas mulheres em relação à prevenção do câncer cérvico-uterino.

Awareness of Cervical Cancer Causes and Predeterminants of Likelihood to Screen Among Women in Haiti

OBJECTIVES

Cervical cancer is the leading cause of cancer deaths among women in Haiti. Given this high disease burden, we sought to better understand women's knowledge of its causes and the sociodemographic and health correlates of cervical cancer screening.

MATERIALS AND METHODS

Participants were 410 adult women presenting at clinics in Léogâne and Port-au-Prince, Haiti. We used bivariate and multivariate logic regression to identify correlates of Pap smear receipt.

RESULTS

Only 29% of respondents had heard of human papillomavirus (HPV), whereas 98% were aware of cervical cancer. Of those aware of cervical cancer, 12% believed that sexually transmitted infections (STIs) cause it, and only 4% identified HPV infection as the cause. Women with a previous sexually transmitted infection were more likely to have had Pap smear (34% vs 71%, odds ratio = 3.45; 95% CI = 1.57-7.59). Screening was also more likely among women who were older than the age of 39 years, better educated, and employed (all p < .05). Almost all women (97%) were willing to undergo cervical cancer screening.

CONCLUSIONS

This sample of Haitian women had limited awareness of HPV and cervical cancer causes; but when provided with health information, they saw the benefits of cancer screening. Future initiatives should provide health education messages, with efforts targeting young and at-risk women.

Vaccine strategies: Optimising outcomes

Successful immunisation programmes generally result from high vaccine effectiveness and adequate uptake of vaccines. In the development of new vaccination strategies, the structure and strength of the local healthcare system is a key consideration. In high income countries, existing infrastructures are usually used, while in less developed countries, the capacity for introducing new vaccines may need to be strengthened, particularly for vaccines administered beyond early childhood, such as the measles or human papillomavirus (HPV) vaccine. Reliable immunisation service funding is another important factor and low income countries often need external supplementary sources of finance. Many regions also obtain support in generating an evidence base for vaccination via initiatives created by organisations including World Health Organization (WHO), the Pan American Health Organization (PAHO), the Agence de Médecine Préventive and the Sabin Vaccine Institute. Strong monitoring and surveillance mechanisms are also required. An example is the efficient and low-cost approaches for measuring the impact of the hepatitis B control initiative and evaluating achievement of goals that have been established in the WHO Western Pacific region. A review of implementation strategies reveals differing degrees of success. For example, in the Americas, PAHO advanced a measles-mumps-rubella vaccine strategy, targeting different population groups in mass, catch-up and follow-up vaccination campaigns. This has had much success but coverage data from some parts of the region suggest that children are still not receiving all appropriate vaccines, highlighting problems with local service infrastructures. Stark differences in coverage levels are also observed among high income countries, as is the case with HPV vaccine implementation in the USA versus the UK and Australia, reflecting differences in delivery settings. Experience and research have shown which vaccine strategies work well and the factors that encourage success, which often include strong support from government and healthcare organisations, as well as tailored, culturally-appropriate local approaches to optimise outcomes.

Cancer mortality in Itapúa--A rural province of Paraguay 2003-2012

BACKGROUND

Itapúa is a rural department in Paraguay with a population of about 500,000 and a high degree of agro-mechanization for the production of soybean and other crops. So far, only basic health care is provided. Here we analyzed the cancer mortality in this region as a first step towards epidemiological data for cancer prevention.

METHODS

We calculated the age-adjusted mortality rates according to world standard (AMRWs) for the major cancer sites in both males and females between 2003 and 2012, and estimated the differences between the capital and more central districts of Itapúa vs. remote districts.

RESULTS

There were about 2000 cancer deaths in the decade studied, with AMRWs for all malignancies of 90.9/100,000 in males from central vs. 49.1/100,000 in remote districts and 69.0/100,000 vs. 45.0/100,000 in women. Cancer was mentioned in 12.4% of all death certificates and outweighed mortality from certain infectious and parasitic diseases (3.6%). Cause of death was ill-defined in 19.6% of all death certificates, especially in remote regions and among the elderly. The part of cancer located in the uterus (47.8%) or cell type of neoplasm of the lymphatic or hematopoietic system (73.1%) were often not specified. The uterus (mainly the cervix) (C53-C55) was the leading cancer site in women with AMRWs of 17.2/100,000 in central and 14.0/100,000 in remote districts, followed by the breast. Lung and prostate were the leading cancer sites among men. The lung cancer mortality rate was 19.3/100,000 in the central region but 9.5/100,000 in remote districts. Although children comprised 36% of the population, only 24 death certificates listed cancer as cause of death in this decade.

CONCLUSIONS

Analysis of cancer mortality in this rural region of Paraguay, which lacks resources for diagnostics and care, revealed an already large number of cases, with higher rates in the central region than in remote districts. Lung and uterus (primarily the cervix) are common cancer sites and indicate the potential for prevention. However, the quality of the vital statistics needs to be improved. The true cancer burden is most likely underestimated, especially in remote regions and children.

Mothers' acceptance of human papillomavirus (HPV) vaccination for daughters in a country with a high prevalence of HPV

Cervical cancer is the second most common cancer among women in Argentina and the mortality rate is not declining despite opportunistic screening. Free-of-charge human papillomavirus (HPV) vaccination of 11-year-old girls was introduced in 2011. Parental acceptance of HPV vaccination is considered to be of great importance for HPV vaccine uptake. However, little is known regarding this factor in Argentina. The aim of the present study was to explore maternal HPV vaccination acceptance, willingness to pay for HPV vaccination and correlates of this willingness, awareness of HPV and HPV-associated disease and behaviors and attitudes associated with HPV vaccination acceptance. A total of 180 mothers of girls aged 9-15 years comprised this quantitative, cross-sectional, survey-based study, conducted at two hospitals in the Mendoza Province. Correlates of willingness to pay for HPV vaccination were obtained using multivariable logistic regression models. Maternal HPV vaccination acceptance was 90%, and 60% of mothers were willing to pay for HPV vaccination. Mothers who were gainfully employed and had a higher disposable household income were significantly more willing to pay for HPV vaccination [odds ratio (OR)=2.54, 95% confidence interval (CI) 1.01-6.38; OR=3.28, 95% CI 1.36-7.94, respectively], as were mothers who were aware of cervical cancer prior to the study (OR=3.22, 95% CI 1.02-10.14). Only one in 10 mothers were informed that HPV vaccination does not offer complete protection against cervical cancer. In conclusion, the present study showed high maternal HPV vaccination acceptance, although acceptance decreased when vaccination was not free-of-charge. Continuous public education campaigns are needed to improve knowledge of HPV, HPV vaccines and HPV-associated disease.

Equity of access to Pap smears: population-based study in Campinas, São Paulo, Brazil

OBJECTIVE

To determine the prevalence of the Papanicolaou exam among women aged 20 to 59 years in the city of Campinas (state of São Paulo, Brazil) and to analyze associations between this test and affiliation to private health insurance plans as well as socioeconomic/demographic variables and health-related behavior.

METHOD

To do so, a population-based, cross-sectional study was carried out. Statistical analyses took the study design into account.

RESULTS

Despite the significant socioeconomic differences between women with and without private health plans, no differences between these groups were found regarding having been submitted to the Papanicolaou test. In fact no differences were found as to socioeconomic and health variables analyzed. Among all variables analyzed, only marital status was significantly associated with having undergone the test. The Brazilian public health system accounted for 55.7% of the exams.

CONCLUSION

The present findings indicate social equity in the city of Campinas regarding the preventive exam for cervical cancer in the age group studied.

Prevalence of human papillomavirus infection and phylogenetic analysis of HPV-16 E6 variants among infected women from Northern Brazil

Background

The main cause of cervical cancer in the world is high risks human papillomavirus infection (mainly represented by HPV-16 and HPV-18), that are associated to the development of malign transformation of the epithelium. HPV prevalence exhibits a wide geographical variability and HPV-16 variants have been related to an increased risk of developing cervical intraepithelial lesion. The aim of this study was to describe DNA-HPV prevalence and HPV-16 variants among a women population from Northern Brazil.

Methods

One hundred and forty three women, during routine cervical cancer screening, at Juruti Project, fulfilled an epidemiological inquiry and were screened through a molecular HPV test. HPV-16 variants were determined by sequencing the HPV-16 E6 open reading frame.

Results

Forty two samples were considered HPV positive (29.4%). None of those had abnormal cytology results. HPV prevalence varied between different age groups (Z(U) = 14.62; p = <0.0001) and high-risk HPVs were more frequent among younger ages. The most prevalent type was HPV-16 (14%) and it variants were classified, predominantly, as European (87.5%).

Conclusions

HPV prevalence in our population was higher than described by others and the most prevalent HPV types were high-risk HPVs. The European HPV-16 variant was the most prevalent among HPV-16 positive samples. Our study reinforces the fact that women with normal cytology and a positive molecular test for high-risk HPVs should be submitted to continuous follow up, in order to verify persistence of infection, promoting an early diagnosis of cervical cancer and/or its precursors.

Cancer in indigenous people in Latin America and the Caribbean: a review

Cancer is a leading cause of death in Latin America but there have been few assessments of the cancer burden for the 10% of the population who are indigenous. Evidence from other world regions suggests cancer survival is poorer for indigenous people than for others due to a greater incidence of case-fatal cancers, later stage at diagnosis, and less cancer treatment. A status report on the cancer profile of indigenous people in Latin America and the Caribbean (LAC) is therefore clearly warranted. We undertook a systematic review of the peer-reviewed literature in academic databases, and considered evidence from cancer registries from 1980, to assess cancer epidemiology among indigenous people in LAC. We identified 35 peer-reviewed articles pertaining to cancer in indigenous people. Rates of cervical cancer in parts of Brazil, Ecuador, and Guyana, stomach cancer rates in regions of Chile and gallbladder rates in Chile and Bolivia, were higher for indigenous compared to others. Breast cancer rates were lower in Ecuador, Brazil, and Chile. Six cancer registries in Brazil provided incidence data but no other reports of incidence, mortality, or survival were identified. There was a paucity of data surrounding the cancer burden of indigenous people in LAC. In view of predicted increases in cancer rates in ensuing decades, and the disparities in burden already experienced by indigenous people in the region, it is imperative that cancer profiles are obtained and cancer control measures identified and prioritized.

[Efficacy of commercially available vaccines against HPV infection in women: a systematic review and meta-analysis]

Persistent HPV infection is a necessary condition for the occurrence of cervical cancer. Prophylactic HPV vaccines have been developed to reduce the incidence of cervical cancer. Two vaccines are commercially available: bivalent (types 16, 18) and quadrivalent (6, 11, 16 and 18). This study aimed to perform a systematic review and metaanalysis of the HPV vaccines' efficacy in women, focusing its performance stratified by clinical outcomes. Randomized controlled trials (RCT) published between 2000 and 2009 were identified from searches of MEDLINE, LILACS and Cochrane Library, and evaluated by two independent reviewers. Six RCT were selected. The vaccines reduced the risk of precursor lesions of cervical cancer, presenting efficacy of 97% (95%CI: 90-99) for CIN 2 and 96% (95%CI: 89-99) for CIN 3, in the per protocol analysis. The efficacies in the analysis by intention to treat were smaller: 63% (95%CI: 52-71) and 42% (95%CI: 26-55), respectively. In order to evaluate its effectiveness on the incidence and mortality rates for cervical cancer, longer-term studies will be needed.

Inequalities in Pap smear screening for cervical cancer in Brazil

OBJECTIVE

To examine the risk factors associated with never being screened for cervical cancer (CC) in Brazil.

METHODS

Using the National Household Sample Survey 2008 (PNAD), we analyzed data from 102,108 Brazilian women ages 25-64years. The patients were analyzed as having been or never having been screened with a Pap smear (Yes/No). Age-adjusted prevalence of never-screening was analyzed using a Chi-squared test. Crude and adjusted models using Poisson regression were performed.

RESULTS

The prevalence of never-screened women for CC was 12.9%, 11.5% and 22.2% in Brazil in general, urban and rural areas, respectively. The Brazilian region with the highest prevalence of never-screening was the North (17.4%, 14.7% and 27.3% in general, urban and rural areas, respectively). The factors associated with a higher risk for never being screened were the following: poverty, younger age, lower educational level, non-white skin color, a greater number of children, no supplemental health insurance and not having visited a doctor in the past 12months.

CONCLUSION

Socioeconomic and demographic conditions lead to inequalities in access to Pap smear screening in Brazil. Public health policy addressing these risk groups is necessary.

Human papillomavirus (HPV) vaccine implementation in low and middle-income countries (LMICs): health system experiences and prospects

•

Multi-method review of challenges introducing HPV vaccine in developing countries.

•

HPV vaccine delivery methods can overcome inadequate health systems.

•

Political will is essential for successful HPV vaccine roll-out.

Prophylactic vaccines for human papillomavirus (HPV) are being introduced in many countries for the prevention of cervical cancer, the second most important cause of cancer-related death in women globally. This is likely to have a significant impact on the future burden of cervical cancer, particularly where screening is non-existent or limited in scale. Previous research on the challenges of vaccinating girls with the HPV vaccine has focused on evidence from developed countries. We conducted a systematic search of the literature in order to describe the barriers and challenges to implementation of HPV vaccine in low- and middle-income countries. We identified literature published post-2006 to September 2012 from five major databases. We validated the findings of the literature review with evidence from qualitative key informant interviews. Three key barriers to HPV vaccine implementation were identified: sociocultural, health systems and political. A linked theme, the sustainability of HPV vaccines programmes in low- and middle-income countries, cuts across these three barriers. Delivering HPV vaccine successfully will require multiple barriers to be addressed. Earlier research in developed countries emphasised sociocultural issues as the most significant barriers for vaccine roll-out. Our evidence suggests that the range of challenges for poorer countries is significantly greater, not least the challenge of reaching girls for three doses in settings where school attendance is low and/or irregular. Financial and political barriers to HPV vaccine roll-out continue to be significant for many poorer countries. Several demonstration and pilot projects have achieved high rates of acceptability and coverage and lessons learned should be documented and shared.

Type-specific human papillomavirus distribution in invasive cervical carcinomas in Paraguay. A study of 432 cases

Cervical carcinoma is the most common malignant tumor among woman in Paraguay. Cytological screening programs have not been successful and a plan for human papillomavirus (HPV) based-screening program and/or vaccination is under evaluation. This study aimed to identify the contribution of HPV genotypes in invasive cervical cancer in Paraguay to provide essential background data to guide and assess the introduction and impact of new preventive strategies based on HPV. Four hundred thirty two histologically confirmed cases (1960-2004) were analyzed. HPV detection in paraffin blocks was performed at the Catalan Institute of Oncology using PCR with SPF-10 broad spectrum primers followed by DNA enzyme immunoassay and genotyping with a reverse hybridization line probe analysis. The majority of cases were squamous cell carcinoma (92.8%). Mean patients age was 48 years old. HPV DNA was detected in 73.1% of the cases and single infections were predominant (97.8%). The most common HPV single types were 16, 18, 45, 33, 31, 52, 35, and 39. 73.1% of HPV positive cases had an HPV 16, 18 as single infection. HPV16 was frequent in SCC whereas HPV 18 and 45 were prevalent in glandular tumors. Significant decrease of HPV 16 with age groups (P-trend = 0.022) and increase in other HPV types (P-trend > 0.001) were observed. The potential impact of HPV 16 and 18 for a vaccination program was 73.1%. The study provide a profile of the HPV situation in the country, with robust clinical, pathological and virological data which would permit a better cervical cancer screening and vaccination programs.

Comparison of human papillomavirus testing and cytology for cervical cancer screening in a primary health care setting in the Democratic Republic of the Congo

OBJECTIVES

We compared the screening performance of conventional Pap cytology and two human papillomavirus (HPV) DNA assays, the original Hybrid Capture 2 (HC2) and an expanded version that tests for 4 additional HPV types (HC2+4; Qiagen Corporation), in the detection of cervical neoplasia among unscreened women in a primary care setting in a suburb of Kinshasa, Democratic Republic of the Congo.

METHODS

All women 30 years or older residing in the area were invited to participate, and 1528 were evaluated by Pap cytology and the two HPV assays, conducted at a European and US reference laboratory, respectively, followed by colposcopy. Cervical biopsies were obtained from all women with abnormal colposcopy and from 290 randomly chosen women with normal colposcopy (to correct for verification bias).

RESULTS

Using a relative light unit of 1 as the cutoff for positivity, 169 and 168 (11%) women tested positive using HC2 and HC2+4, respectively. HC2 and HC2+4 were in agreement in 98.6% of cases (Kappa=0.94; 95% confidence interval: 0.91-0.96). Both assays were sensitive (~83%) and specific (~91%) for the detection of cervical intraepithelial neoplasia-2 or worse disease. Irrespective of the cutoff point used to define positivity, Pap cytology was both less sensitive and more specific than HC2 or HC2+4. For instance, cytology was 63% sensitive and 97% specific when a cutoff point of low-grade squamous intraepithelial lesions or worse was used.

CONCLUSIONS

Among unscreened women, HC2 and HC2+4 had similar screening accuracy for cervical neoplasia, and both were more sensitive but less specific than Pap cytology.

Regional variation in histopathology-specific incidence of invasive cervical cancer among Peruvian women

OBJECTIVE

To evaluate patterns of cervical cancer incidence in Peru by examining variation in 2 common histopathologic types, squamous cell carcinoma (SCC) and adenocarcinoma (ADC), and analyzing trends over time.

METHODS

Data on the incidence of invasive cervical cancer between 1984 and 2006 were obtained from 3 population-based cancer registries in Peru: Lima, Trujillo, and Arequipa. For each registry, data quality assessment was performed, crude and age-specific incidence was calculated, and time trends were analyzed.

RESULTS

Overall and SCC incidence varied across registries but incidence of ADC did not. Overall and SCC incidence showed significant declines in Trujillo (P<0.05) and modest declines in Lima (P>0.05) over time. ADC incidence showed marginally significant increases among women aged 15-29 years in Trujillo (P=0.10) and modest increases among young women in Lima (P>0.05).

CONCLUSION

Population-based cancer registries were an efficient source of data for evaluating the incidence of cervical cancer once data quality had been established. Geographic and temporal variations in cervical cancer burden were documented in Peru. The trends suggest that cervical ADC is increasing among young women in urban Peru, particularly in Trujillo. We recommend supplementing current Papanicolaou test screening with complementary methods of cervical cancer control, including human papillomavirus (HPV) vaccination and HPV DNA testing.

Health and economic impact of HPV 16/18 vaccination and cervical cancer screening in Eastern Africa

Eastern Africa has the world's highest cervical cancer incidence and mortality rates. We used epidemiologic data from Kenya, Mozambique, Tanzania, Uganda, and Zimbabwe to develop models of HPV-related infection and disease. For each country, we assessed HPV vaccination of girls before age 12 followed by screening with HPV DNA testing once, twice, or three times per lifetime (at ages 35, 40, 45). For women over age 30, we assessed only screening (with HPV DNA testing up to three times per lifetime or VIA at age 35). Assuming no waning immunity, mean reduction in lifetime cancer risk associated with vaccination ranged from 36 to 45%, and vaccination followed by screening once per lifetime at age 35 with HPV DNA testing ranged from 43 to 51%. For both younger and older women, the most effective screening strategy was HPV DNA testing three times per lifetime. Provided the cost per vaccinated girl was less than I$10 (I$2 per dose), vaccination had an incremental cost-effectiveness ratio [I$ (international dollars)/year of life saved (YLS)] less than the country-specific per capita GDP, a commonly cited heuristic for "very cost-effective" interventions. If the cost per vaccinated girl was between I$10 (I$2 per dose) and I$25 (I$5 per dose), vaccination followed by HPV DNA testing would save the most lives and would be considered good value for public health dollars. These results should be used to catalyze design and evaluation of HPV vaccine delivery and screening programs, and contribute to a dialogue on financing HPV vaccination in poor countries.

Scaling up human papillomavirus vaccination: a conceptual framework of vaccine adherence

This review article provides a conceptual framework for human papillomavirus (HPV) vaccine acceptance and adherence, with a focus on improving understanding of the sociocultural factors impacting vaccine adherence behaviour. We include a systematic review of the slowly expanding literature on HPV vaccine acceptability and uptake in developed nations, as well as the relatively few publications from poorer nations, where more than 80% of global cervical cancer related deaths occur and where the vaccine will probably have the largest impact. We suggest that this conceptual framework will not only improve our understanding of HPV vaccine uptake and adherence, but it may also guide future sociobehavioural research geared towards improving adherence to the HPV vaccine and other multi-step vaccines in a young population at risk for sexually transmissible infections.

Impact of a quadrivalent HPV6/11/16/18 vaccine in Mexican women: public health implications for the region

BACKGROUND AND AIMS

Recognition of human papillomavirus (HPV) as a necessary cause of cervical cancer (CC) led to new perspectives for its control and the demonstration of an effective primary prevention strategy through vaccination. We undertook this study to evaluate the safety, efficacy and immunogenicity of a quadrivalent HPV6/11/16/18 vaccine in Mexican women.

METHODS

A total of 679 Mexican women between 18 and 23 years old participated in two Phase III double-blind, randomized, placebo-controlled clinical trials of a quadrivalent HPV 6/11/16/18 vaccine. Women were enrolled who tested negative for pregnancy and reported having four or less sexual partners during their lifetime. Vaccine or placebo was administered at day 1, month 2 and month 6.

RESULTS

Among Mexican women who were naïve to the respective vaccine type at enrollment, the quadrivalent vaccine was highly efficacious, preventing 100% of HPV6/11/16/18-related cervical intraepithelial neoplasia grade 2/3, adenocarcinoma in situ, condyloma and vaginal intraepithelial neoplasia. Statistical significance was not reached for every endpoint due to the limited sample size. Vaccination was generally well tolerated and immunogenic.

DISCUSSION

To widely administer the vaccine, collaborative efforts should be coordinated among public, private and local community sectors. In light of the scarce knowledge of many health professionals with respect to the primary prevention of CC, it will be necessary to educate health providers on the advantages and specific recommendations of HPV vaccines and secondary prevention. Decision making should be based on scientific evidence, allowing health professionals to provide an organized social response that supports the universal right to health.

EUROGIN 2008 roadmap on cervical cancer prevention

The EUROGIN 2008 Roadmap represents a continuing effort to provide updated information on primary and secondary prevention of cervical cancer. The report addresses several areas including the progress made toward global implementation of currently licensed human papillomavirus (HPV) vaccines, the possibilities and value of future-generation HPV vaccines, endpoints under consideration for evaluation of candidate HPV vaccines, and monitoring impact of HPV vaccination programmes that can be implemented within developed and less-developed countries. For the sake of completeness, a short update on the evolution of HPV testing in primary screening programmes at present and after HPV vaccine introduction has also been included. The report is available on the EUROGIN website (www.eurogin.com).