Human papillomavirus infection and related cancers in sub-Saharan Africa: burden and tools for prevention

Examining barriers and facilitators of HPV vaccination in Nigeria, in the context of an innovative delivery model: a mixed-methods study

Background

More than 80% of cervical cancer cases diagnosed globally are in low-income and middle-income countries. In sub-Saharan Africa, where treatment facilities are widely unavailable, it is a leading cause of cancer deaths in women. Human papillomavirus (HPV) vaccination, which is known to prevent almost 90% of cases of cervical cancer, has low uptake in this region, and little is known about the behaviour of those who have been offered the HPV vaccine. This knowledge is critical to guide policy-makers in sub-Saharan Africa on how best to roll out the vaccine and ensure successful and sustainable HPV vaccination programmes.

Methods

To better understand uptake of the HPV vaccine among schoolgirls in Nigeria, we designed a mixed-methods convergent study, with a case-control quantitative arm that recruited caregivers of adolescent schoolgirls as cases (those who accepted vaccination) and controls (those who did not accept vaccination). For the qualitative study, we conducted 10 focus group discussions with of caregivers and 6 in-depth interviews with school administrators, vaccination sponsors and policy-makers.

Results

Those with high awareness of HPV vaccination had three times the odds of uptake (adjusted OR (aOR) 2.6, 95% CI 1.54 to 4.31, p=0.002). Giving HPV vaccines in school was also associated with uptake (aOR 3.1, 95% CI 1.54 to 6.43, p=0.002). Being offered free HPV vaccination was significant in the bivariate analysis (aOR 1.67, 95% CI 1.03 to 2.70, p=0.039) but was marginally significant in the multivariate analysis (aOR 0.63, 95% CI 0.37 to 1.06, p=0.086). Qualitative themes supported these findings, demonstrating that effective awareness and convenience of vaccination could encourage uptake. Key barriers to uptake included lack of affordability and limited availability of vaccines.

Conclusions

Effective awareness, administering HPV vaccines in school and subsidising HPV vaccination costs can improve uptake.

Modeling for Predictors of Knowledge Score on Etiology and Prevention Strategies for Cervical Cancer Among Women of Reproductive Age in Ibadan

PURPOSE

Poor knowledge regarding cervical cancer in at-risk populations directly affects health-seeking behavior and is associated with high mortality among women with cervical cancer. This study aims to evaluate the knowledge of women regarding the causes, risk factors, and prevention strategies of cervical cancer.

METHODS

A multistage cross-sectional study of 1,002 women of reproductive age (18-49 years) in Ibadan was conducted. Knowledge of cervical cancer risk causes and prevention strategies was assessed using 13 and 9 question items, respectively. The knowledge score was graded as 0 (no knowledge), 1-4 (poor knowledge), or ≥ 5 (good knowledge). The proportional or partial proportional odds model was used to fit 3 models using the forward stepwise selection. All analysis was performed using Stata 15.0 (Stata Corp, College Station, TX).

RESULTS

The median age of participants was 29 years (interquartile range [IQR], 23-35 years). The median knowledge scores of participants on causes and prevention strategies of cervical cancer were 3 (IQR, 0-4) and 3 (IQR, 0-5), respectively. The assessment of knowledge on causes and prevention strategies for cervical cancer revealed that having multiple sexual partners and no previous opportunity for counseling on cervical cancer screening were factors associated with lower odds of knowledge.

CONCLUSION

The knowledge of women about the risk factors, causes, and prevention strategies of cervical cancer was poor. It is worrisome that poor knowledge was common among women with potential demographic risk factors for cervical cancer. We recommend innovative community mobilization to improve women’s knowledge of the risk factors associated with cervical cancer and prevention strategies.

Effect of Cryotherapy vs Loop Electrosurgical Excision Procedure on Cervical Disease Recurrence Among Women With HIV and High-Grade Cervical Lesions in Kenya: A Randomized Clinical Trial

Importance

The World Health Organization recommends cryotherapy or loop electrosurgical excision procedure (LEEP) for histologically confirmed cervical intraepithelial neoplasia (CIN) grade 2 or higher regardless of HIV status. Cryotherapy is more feasible in resource-limited settings but may be less effective for women living with HIV.

Objective

To evaluate whether cryotherapy or LEEP is a more effective treatment for high-grade cervical lesions among women with HIV.

Design, Setting, and Participants

Single-center randomized trial conducted among women with HIV and CIN grade 2 or 3. From June 2011 to September 2016, women with HIV in Kenya underwent cervical screening with Papanicolaou testing and confirmatory biopsy. The final date on which a study procedure was administered was September 7, 2016.

Interventions

Women with HIV infection and CIN grade 2 or 3 were randomized 1:1 to receive cryotherapy (n = 200) or LEEP (n = 200) and were followed up every 6 months for 24 months with a Papanicolaou test and confirmatory biopsy.

Main Outcome and Measures

The primary outcome was disease recurrence, defined as CIN grade 2 or higher on cervical biopsy, during the 24-month follow-up period.

Results

Among 400 women who were randomized (median age, 37.4 [interquartile range, 31.9-43.8] years), 339 (85%) completed the trial. Over 2 years, 60 women (30%) randomized to cryotherapy had recurrent CIN grade 2 or higher vs 37 (19%) in the LEEP group (relative risk, 1.71 [95% CI, 1.12-2.65]; risk difference, 7.9% [95% CI, 1.9%-14.0%]; P = .01). Adverse events occurred in 40 women (45 events, including change in pathology and death due to other causes) in the cryotherapy group and in 30 women (38 events, including change in pathology and unrelated gynecological complications) in the LEEP group.

Conclusions and Relevance

In this single-center study of women with HIV infection and CIN grade 2 or 3, treatment with LEEP compared with cryotherapy resulted in a significantly lower rate of cervical neoplasia recurrence over 24 months. Cost-effectiveness analysis is necessary to determine whether the additional benefit of LEEP represents an efficient use of the additional resources that would be required.

Trial Registration

ClinicalTrials.gov Identifier: NCT01298596.

The Need for Societal Investment to Improve Cervical Cancer Outcomes in Nigeria: A commentary

Although cervical cancer is a preventable cancer with a well-known natural history, it remains a huge burden in developing countries of sub-Saharan Africa where organized cervical cancer screening services are lacking. Developed countries that have invested on providing organized screening programs have made substantial progress in reducing both incidence and mortality due to cervical cancer. Implementing evidence-based interventions such as human papillomavirus (HPV) vaccination of young girls, early detection and treatment of premalignant conditions of the cervix through conventional Pap cytology, HPV screening or visual aided inspection with acetic acid could significantly reduce incidence of new cases at population level. Societal investment for such preventive services and provision of effective treatment for those diagnosed at early stages will yield economic benefits in reducing premature deaths of women at the prime of their productive lives. From a societal perspective, this should be a priority area for national investment towards the achievement of sustainable development in Nigeria and similar settings in Africa.

Human papillomavirus (HPV) awareness and vaccine receptivity among Senegalese adolescents

OBJECTIVE

To examine HPV vaccine awareness and receptivity among adolescents and young adults in Senegal.

METHODS

Participants from six high schools and five community centres across five regions of Senegal (n = 2286) completed a self-administered questionnaire in October and November 2014. The study assessed HPV awareness and receptivity towards receiving the HPV vaccine. Multivariable logistic regression explored statistically significant relationships between the predictor variables and both outcomes.

RESULTS

Twenty-seven percent had heard of HPV. Among those who had heard of HPV (n = 616), only 28% indicated willingness to vaccinate. Multivariable analysis showed that respondents from rural areas had 63% higher odds (95% CI: 1.24, 2.12) of having heard of HPV than those in urban areas. Respondents with fathers who had completed higher education had 41% higher odds (95% CI: 1.04, 1.92) of being aware of HPV (P < 0.05); however, every level of father's education (as compared to no education at all) was negatively associated with willingness to vaccinate. Respondents who had previously spoken to a healthcare professional about the HPV vaccine had 80% higher odds (95% CI: 1.16, 2.81) of willingness to vaccinate than those who did not speak to a provider about the vaccine.

CONCLUSIONS

Healthcare providers and parents are important stakeholders in disseminating HPV vaccine information. Given the overall low levels of awareness, there is a great opportunity for public health communication efforts to craft health messaging and information in a way to maximise receptivity, outlining benefits and providing information on the minimal risks associated with the vaccine.

Barriers to Cervical Cancer Screening in Burkina Faso: Needs for Patient and Professional Education

Cervical cancer is among the leading causes of cancer deaths for women in low-income African countries, such as Burkina Faso. Given that cervical cancer is a preventable disease through early detection and vaccination, this study aimed at understanding the barriers to cervical cancer early detection in Ouagadougou, the capital city of Burkina Faso. Women seeking screening and treatment for cervical cancer (n = 351) during the period of May-August 2014, at the Yalgado Ouedraogo University Hospital, were interviewed about their knowledge, attitudes, and practices toward cervical cancer. Interview questions elicited information about sociodemographic of participants, history of screening, knowledge of cervical cancer, and attitudes toward cervical screening. Scores were assigned to responses of questions and knowledge, and tertitles of distributions were used for comparison. A multivariate logistic regression was performed to predict cervical screening. Study participants were relatively young (37.5 ± 10.7 years) and predominately resident of urban areas (83.8 %), and over half had no or less than high school education. Over 90 % of participants had heard about cervical cancer, and about 55 % of them had intermediate-level knowledge of the disease, its screening, and/or risk factors. Knowledge level was lower among rural than urban residents. Predictors of screening included higher level of education (odds ratio (OR) = 2.2; 95 % confidence interval (CI) 1.48-3.23), older age (OR = 1.1; 95 % CI 1.06-1.12), higher socioeconomic standard (SES) (OR = 1.5; 95 % CI 1-2.37), urban residence (OR = 2.0; 95 % CI 1.19-3.25), encouragement for screening by a health care worker (1.98; 95 % CI 1.06-3.69), and employment (OR = 1.9; 95 % CI 1.13-3.11). Low awareness and socioeconomic barriers lead to underutilization of screening services of women. Motivation and education by healthcare workers are important factors for increasing screening rates. Organized patient and professional education programs in gynecologic services are warranted for improving screening in Burkina Faso and other low-resource countries in Africa.

Evaluation of safety and immunogenicity of a quadrivalent human papillomavirus vaccine in healthy females between 9 and 26 years of age in Sub-Saharan Africa

Due to sporadic and not easily accessible cervical cancer screening, human papillomavirus (HPV)-related cervical cancer is a leading cause of cancer death in Sub-Saharan African women. This study was designed to assess the safety and immunogenicity of a quadrivalent human papillomavirus (qHPV) vaccine in sub-Saharan African women. This seven month, double-blind study enrolled 250 healthy, human immunodeficiency virus (HIV)-uninfected females ages 9-26 residing in Ghana, Kenya, and Senegal. Thirty females ages 13-15 and 120 females ages 16-26 received qHPV vaccine. In addition, 100 females ages 9-12 y were randomized in a 4:1 ratio to receive either qHPV vaccine (n = 80) or placebo (n = 20 ). The primary immunogenicity hypothesis was that an acceptable percentage of subjects who received the qHPV vaccine seroconvert to HPV6/11/16/18 at 4 weeks post-dose 3, defined as the lower bound of the corresponding 95% confidence interval (CI) exceeding 90%. The primary safety objective was to demonstrate that qHPV vaccine was generally well tolerated when administered in a 3-dose regimen. The pre-specified statistical criterion for the primary immunogenicity hypothesis was met: the lower bound of the 95% exact binomial CI on the seroconversion rate was at least 98% for each vaccine HPV type and all subjects seroconverted by 4 weeks post-dose 3. Across vaccination groups, the most common adverse events (AE) were at the injection site, including pain, swelling, and erythema. No subject discontinued study medication due to an AE and no serious AEs were reported. There were no deaths. This study demonstrated that qHPV vaccination of sub-Saharan African women was highly immunogenic and generally well tolerated.

HIV Status and Acute Hematologic Toxicity Among Patients With Cervix Cancer Undergoing Radical Chemoradiation

INTRODUCTION

Women infected with the human immunodeficiency virus (HIV) have a higher risk of developing cervix carcinoma than do other women who are thought to be more vulnerable to acute toxicities during chemoradiation. We compared HIV-positive/HIV-negative patients with cervix carcinoma at a single institution with respect to cancer treatment toxicities.

METHODS AND MATERIALS

Among patients with stage Ib1-IIIb invasive cervical carcinoma who received radiation or chemoradiation with curative intent, we evaluated demographic and clinical characteristics of HIV-positive and HIV-negative patients. Treatment regimens were documented and toxicities scored as per Radiation Therapy Oncology Group guidelines. We developed logistic regression models for the associations of grade 3/4 toxicities with HIV status.

RESULTS

Complete data were available on 213 patients, including 36 (16.8%) who were HIV positive. More than 85% of both HIV-positive and HIV-negative patients received a minimum of 68-Gy equivalent dose in 2-Gy-fraction external beam and high-dose-rate brachytherapy. More HIV-positive than HIV-negative patients were prescribed radiation alone (38.9% vs 24.29%, P = 0.01), experienced at least 1 grade 3/4 toxicity (38.9% vs 26.6%), or developed grade 3/4 leucopenia (30.6% vs 10.2%, P = 0.003).In a multivariable model, patients who developed a grade 3/4 toxicity were 4 times as likely to have received chemotherapy (odds ratio, 4.41 [95% confidence interval, 1.76-11.1]; P = 0.023) and twice as likely to be HIV positive (odds ratio 2.16 [95% confidence interval, 0.98-4.8]; P = 0.05) as women who did not experience such toxicities.

CONCLUSIONS

HIV-positive patients with cervical carcinoma received adequate radiotherapy but were less likely than HIV-negative patients to complete chemotherapy. Few HIV-positive or HIV-negative patients who received radiotherapy without chemotherapy experienced grade 3/4 toxicity. However, among patients who received chemotherapy, those who were HIV positive were more likely than others to experience hematologic toxicity.

Assessing cost-effectiveness of HPV vaccines with decision analytic models: what are the distinct challenges of low- and middle-income countries? A protocol for a systematic review

BACKGROUND

Cervical cancer poses a huge health burden, both to developed and developing nations, making prevention and control strategies necessary. However, the challenges of designing and implementing prevention strategies differ for low- and middle-income countries (LMICs) as compared to countries with fully developed health care systems. Moreover, for many LMICs, much of the data needed for decision analytic modelling, such as prevalence, will most likely only be partly available or measured with much larger uncertainty. Lastly, imperfect implementation of human papillomavirus (HPV) vaccination may influence the effectiveness of cervical cancer prevention in unpredictable ways. This systematic review aims to assess how decision analytic modelling studies of HPV cost-effectiveness in LMICs accounted for the particular challenges faced in such countries. Specifically, the study will assess the following: (1) whether the existing literature on cost-effectiveness modelling of HPV vaccines acknowledges the distinct challenges of LMICs, (2) how these challenges were accommodated in the models, (3) whether certain parameters systemically exhibited large degrees of uncertainty due to lack of data and how influential were these parameters on model-based recommendations, and (4) whether the choice of modelling herd immunity influences model-based recommendations, especially when coverage of a HPV vaccination program is not optimal.

METHODS

We will conduct a systematic review to identify suitable studies from MEDLINE (via PubMed), EMBASE, NHS Economic Evaluation Database (NHS EED), EconLit, Web of Science, and CEA Registry. Searches will be conducted for studies of interest published since 2006. The searches will be supplemented by hand searching of the most relevant papers found in the search. Studies will be critically appraised using Consolidated Health Economic Evaluation Reporting Standards (CHEERS) statement checklist. We will undertake a descriptive, narrative, and interpretative synthesis of data to address the study objectives.

DISCUSSION

The proposed systematic review will assess how the cost-effectiveness studies of HPV vaccines accounted for the distinct challenges of LMICs. The gaps identified will expose areas for additional research as well as challenges that need to be accounted for in future modelling studies.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42015017870.

Health care access dimensions and cervical cancer screening in South Africa: analysis of the world health survey

BACKGROUND

Cervical cancer is the most commonly diagnosed cancer and the leading cause of cancer mortality among women in sub-Saharan Africa. Recent recommendations for cervical cancer primary prevention highlight HPV vaccination, and secondary prevention through screening. However, few studies have examined the different dimensions of health care access, and how these may influence screening behavior, especially in the context of clinical preventive services.

METHODS

Using the 2003 South Africa World Health Survey, we determined the prevalence of cervical cancer screening with pelvic examinations and/or pap smears among women ages 18 years and older. We also examined the association between multiple dimensions of health care access and screening focusing on the affordability, availability, accessibility, accommodation and acceptability components.

RESULTS

About 1 in 4 (25.3%, n = 65) of the women who attended a health care facility in the past year got screened for cervical cancer. Screened women had a significantly higher number of health care providers available compared with unscreened women (mean 125 vs.12, p-value <0.001), and were more likely to have seen a medical doctor compared with nurses/midwives (73.1% vs. 45.9%, p-value = 0.003). In multivariable analysis, every unit increase in the number of health care providers available increased the likelihood of screening by 1% (OR = 1.01, 95% CI: 1.00, 1.01). In addition, seeing a nurse/midwife compared to a medical doctor reduced the likelihood of screening by 87% (OR = 0.13, 95% CI: 0.04, 0.42).

CONCLUSIONS

Our findings suggest that cost issues (affordability component) and other patient level factors (captured in the acceptability, accessibility and accommodation components) were less important predictors of screening compared with availability of physicians in this population. Meeting cervical cancer screening and HPV vaccination goals will require significant investments in the health care workforce, improving health care worker density in poor and rural areas, and improved training of the existing workforce.