Achieving equity in cervical cancer screening in low- and middle-income countries (LMICs): Strengthening health systems using a systems thinking approach.

The World Health Organization (WHO) is leading a call to action to eliminate cervical cancer by the end of the century through global implementation of two effective evidence-based preventive interventions: HPV vaccination and cervical screening and management (CSM). Models estimate that without intervention, over the next 50 years 12.2 million new cases of cervical cancer will occur, nearly 60% of which are preventable only through CSM. Given that more than 80% of the cervical cancer occurs in low- and middle-income countries (LMICs), scaling up sustainable CSM programs in these countries is a top priority for achieving the global elimination goals. Multiple technologies have been developed and validated to meet this need. Now it is critical to identify strategies to implement these technologies into complex, adaptive health care delivery systems. As part of the coordinated cervical cancer elimination effort, we applied a systems thinking lens to reflect on our experiences with implementation of HPV-based CSM programs using the WHO health systems framework. While many common health system barriers were identified, the effectiveness of implementation strategies to address them was context dependent; often reflecting differences in stakeholder's belief in the quality of the evidence supporting a CSM algorithm, the appropriateness of the evidence and algorithm to context, and the 'implementability' of the algorithm under realistic assessments of resource availability and constraints. A structured planning process, with early and broad stakeholder engagement, will ensure that shared-decisions in CSM implementation are appropriately aligned with the culture, values, and resource realities of the setting.

Barriers and innovative interventions for early detection of cervical cancer.

Cervical cancer has decreased significantly over the past 30 years in some countries. However, it remains among the leading causes of cancer deaths in low-income, and racial/ethnic minority women. Cervical cancer prevention technologies are not always available. Laboratories are often not well equipped to use them. HPV information has not been widely disseminated. WHO guidelines, and US and Latin American data provide context for strategies on effective interventions to reduce cervical cancer disparities. Systemic, personal and cultural barriers, combined with decision-making guidelines, and impactful messaging can accelerate reductions in cervical cancer health inequities in the Americas.

El cáncer cervicouterino ha disminuido significativamente en los últimos 30 años, pero sigue siendo una de las principales causas de muerte entre mujeres de bajos recursos y minorías raciales/étnicas. Las tecnologías preventivas del cáncer cervicouterino no están siempre disponibles y los laboratorios no están siempre bien equipados para utilizarlas. La información sobre el VPH no ha sido difundida ampliamente. La OMS y datos de EEUU y Latinoamérica ofrecen estrategias para reducir el cáncer cervicouterino. El entendimiento de las barreras sistémicas, personales y culturales, dentro de un marco de toma de decisiones, y mensajes innovadores puede reducir las barreras asociadas con el cáncer cervicouterino en las Américas.

Barriers and innovative interventions for early detection of cervical cancer / Barreras e intervenciones innovadoras para la detección temprana del cáncer cervicouterino

Abstract: Cervical cancer has decreased significantly over the past 30 years in some countries. However, it remains among the leading causes of cancer deaths in low-income, and racial/ethnic minority women. Cervical cancer prevention technologies are not always available. Laboratories are often not well equipped to use them. HPV information has not been widely disseminated. WHO guidelines, and US and Latin American data provide context for strategies on effective interventions to reduce cervical cancer disparities. Systemic, personal and cultural barriers, combined with decision-making guidelines, and impactful messaging can accelerate reductions in cervical cancer health inequities in the Americas.

Resumen: El cáncer cervicouterino ha disminuido significativamente en los últimos 30 años, pero sigue siendo una de las principales causas de muerte entre mujeres de bajos recursos y minorías raciales/étnicas. Las tecnologías preventivas del cáncer cervicouterino no están siempre disponibles y los laboratorios no están siempre bien equipados para utilizarlas. La información sobre el VPH no ha sido difundida ampliamente. La OMS y datos de EEUU y Latinoamérica ofrecen estrategias para reducir el cáncer cervicouterino. El entendimiento de las barreras sistémicas, personales y culturales, dentro de un marco de toma de decisiones, y mensajes innovadores puede reducir las barreras asociadas con el cáncer cervicouterino en las Américas.

Interplay between the temporal dynamics of the vaginal microbiota and human papillomavirus detection.

BACKGROUND: We sought to describe the temporal relationship between vaginal microbiota and human papillomavirus (HPV) detection. METHODS: Thirty-two reproductive-age women self-collected midvaginal swabs twice weekly for 16 weeks (937 samples). Vaginal bacterial communities were characterized by pyrosequencing of barcoded 16S rRNA genes and clustered into 6 community state types (CSTs). Each swab was tested for 37 HPV types. The effects of CSTs on the rate of transition between HPV-negative and HPV-positive states were assessed using continuous-time Markov models. RESULTS: Participants had an average of 29 samples, with HPV point prevalence between 58%-77%. CST was associated with changes in HPV status (P<.001). Lactobacillus gasseri-dominated CSTs had the fastest HPV remission rate, and a low Lactobacillus community with high proportions of the genera Atopobium (CST IV-B) had the slowest rate compared to L. crispatus-dominated CSTs (adjusted transition rate ratio [aTRR], 4.43, 95% confidence interval [CI], 1.11-17.7; aTRR, 0.33, 95% CI, .12-1.19, respectively). The rate ratio of incident HPV for low Lactobacillus CST IV-A was 1.86 (95% CI, .52-6.74). CONCLUSIONS: Vaginal microbiota dominated by L. gasseri was associated with increased clearance of detectable HPV. Frequent longitudinal sampling is necessary for evaluation of the association between HPV detection and dynamic microbiota.

Differences in patterns of high-risk human papillomavirus infection between urban and rural low-resource settings: cross-sectional findings from Mali.

BACKGROUND: The burden of cervical cancer is disproportionately high in low-resource settings. With limited implementation of human papillomavirus (HPV) vaccines on the horizon in the developing world, reliable data on the epidemiology of high-risk HPV (HR-HPV) infection in distinct geographic populations is essential to planners of vaccination programs. The purpose of this study was to determine whether urban patterns of HR-HPV occurrence can be generalized to rural areas of the same developing country, using data from Mali, West Africa, as an example. METHODS: Urban and rural women in Mali participated in a structured interview and clinician exam, with collection of cervical samples for HPV DNA testing, to determine HR-HPV prevalence and correlates of infection. Correlates were assessed using bivariate analysis and logistic regression. RESULTS: A total of 414 women (n=202 urban women; n=212 rural women) were recruited across both settings. The prevalence of HR-HPV infection in rural women was nearly twice that observed in urban women (23% v. 12%). Earlier age of sexual debut and fewer pregnancies were associated with HR-HPV infection among urban women, but not rural women. Twenty-six percent of urban women who had sexual intercourse by age 14 had an HR-HPV infection, compared to only 9% of those who had later sexual debut (p<0.01). Overall, age, income, and polygamy did not appear to have a relationship with HR-HPV infection. CONCLUSIONS: Compared to urban women, rural women were significantly more likely to be infected with high-risk HPV. The patterns and risk factors of HR-HPV infection may be different between geographic areas, even within the same developing country. The high prevalence in both groups suggests that nearly all rural women and most urban women in Mali will be infected with HR-HPV during their lifetime, so the effects of risk factors may not be statistically apparent. To control HPV and cervical cancer in West Africa and the rest of the developing world, planners should prioritize vaccination in high-burden areas.

Human papillomavirus prevalence and cytopathology correlation in young Ugandan women using a low-cost liquid-based Pap preparation.

Screening for HPV-driven cervical dysplasia and neoplasia is a significant public health concern in the developing world. The purpose of this study was to use a manual, low-cost liquid-based Pap preparation to determine HPV prevalence in HIV-positive and HIV-negative young women in Kampala, Uganda and to correlate cervical cytopathology with HPV-DNA genotype. About 196 post-partum women aged 18-30 years underwent rapid HIV testing and pelvic examination. Liquid-based cervical cytology samples were processed using a low-cost manual technique. A DNA collection device was used to collect specimens for HPV genotyping. HIV and HPV prevalence was 18 and 64%, respectively. Overall, 49% of women were infected with a high-risk HPV genotype. The most common high-risk HPV genotypes were 16 (8.2%), 33 (7.7%), 35 (6.6%), 45 (5.1%), and 58 (5.1%). The prevalence of HPV 18 was 3.6%. HIV-positive women had an HPV prevalence of 86% compared to 59% in HIV-negative women (P = 0.003). The prevalence of HPV 16/18 did not differ by HIV status. HIV-positive women were infected with a significantly greater number of HPV genotypes compared to HIV-negative women. By multivariate analysis, the main risk factor for HPV infection was coinfection with HIV. HIV-positive women were four times more likely to have abnormal cytology than HIV-negative women (43% vs. 11.6%, P < 0.001). These data highlight that HIV infection is a strong risk factor for HPV infection and resultant abnormal cervical cytology. Notably, the manual low-cost liquid-based Pap preparation is practical in this setting and offers an alternate method for local studies of HPV vaccine efficacy.

Baseline assessment of prevalence and geographical distribution of HPV types in Chile using self-collected vaginal samples.

BACKGROUND: Chile has broad variations in weather, economics and population from the far desert north (Region 1) to the cold, icy south (Region 12). A home-based self-collected vaginal sampling was nested in the 2003 Chilean population-based health survey in order to explore the possibility of a type-specific geographical variation for human papillomavirus METHODS: The population was a national probability sample of people 17 years of age and over. Consenting women provided self-collected cervicovaginal swabs in universal collection media (UCM). DNA was extracted and typed to 37 HPV genotypes using PGMY consensus PCR and line blot assay. Weighted prevalence rates and adjusted OR were calculated. RESULTS: Of the 1,883 women participating in the health survey, 1,219 (64.7%) provided a cervicovaginal sample and in 1,110 (56.2% of participants and 66.5% of those eligible) the samples were adequate for analysis. Refusal rate was 16.9%. HPV prevalence was 29.2% (15.1% high-risk HPV and 14.1% low-risk HPV). Predominant high-risk types were HPV 16, 52, 51, 56 and 58. Predominant low-risk HPVs were HPV 84, CP6108, 62, 53 and 61. High-risk and low-risk HPV rates were inversely correlated between the regions. High-risk HPV prevalence was highest among the youngest women, whereas low-risk HPV increased slightly with age. CONCLUSION: Self-obtained vaginal sampling is adequate for monitoring HPV in the community, for identifying high-risk areas, and for surveying the long term impact of interventions.

Validation of a low-cost, liquid-based screening method for cervical intraepithelial neoplasia.

OBJECTIVE: The objective of the study was to validate a low-cost, liquid-based method for cervical cancer screening. STUDY DESIGN: We conducted a retrospective, split-sample comparison of 300 liquid-based cervical cytology samples from a group of 150 human immunodeficiency virus-seropositive women and 150 women from low-risk general gynecology clinics whose specimens were screened via standard liquid-based methodology as part of routine care. Residual samples from each specimen were used to prepare a slide using a novel, inexpensive manual membrane method of liquid-based cytology. These slides were screened by a cytotechnologist and abnormal cases were reviewed by a pathologist. Final diagnoses from the manual membrane method of liquid-based cytology slides were compared with the original diagnoses and available cervical biopsy data. RESULTS: There was good overall agreement between the manual membrane method of liquid-based cytology and original cytology diagnoses (76.3% agreement; kappa = 0.52, 95% confidence interval 0.44 to 0.59). Using available biopsy data to determine the accuracy of each method to identify high-grade squamous intraepithelial lesions, the manual membrane method of liquid-based cytology method was found to have a higher sensitivity (71.4% versus 57.1%) and lower specificity (82.1% versus 89.7%). The slightly higher referral rate to colposcopy using the manual membrane method of liquid-based cytology method was limited to women from the low-risk general gynecology clinics (16.7% versus 12.0%, P = .05). CONCLUSION: The low-cost manual membrane method of liquid-based cytology cervical cytology method is comparable with a standard commercial method. Consequently, it may be of value in alternative screening strategies in resource-limited settings.