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Estimating the incidence of breast cancer in Africa: a systematic review and meta-analysis.

ABSTRACT: Breast cancer is estimated to be the most common cancer worldwide. We sought to assemble publicly available data from Africa to provide estimates of the incidence of breast cancer on the continent.A systematic search of Medline, EMBASE, Global Health and African Journals Online (AJOL) was conducted. We included population- or hospital-based registry studies on breast cancer conducted in Africa, and providing estimates of the crude incidence of breast cancer among women. A random effects meta-analysis was employed to determine the pooled incidence of breast cancer across studies.The literature search returned 4648 records, with 41 studies conducted across 54 study sites in 22 African countries selected. We observed important variations in reported cancer incidence between population- and hospital-based cancer registries. The overall pooled crude incidence of breast cancer from population-based registries was 24.5 per 100?000 person years (95% confidence interval (CI) 20.1-28.9). The incidence in North Africa was higher at 29.3 per 100?000 (95% CI 20.0-38.7) than Sub-Saharan Africa (SSA) at 22.4 per 100?000 (95% CI 17.2-28.0). In hospital-based registries, the overall pooled crude incidence rate was estimated at 23.6 per 100?000 (95% CI 18.5-28.7). SSA and Northern Africa had relatively comparable rates at 24.0 per 100?000 (95% CI 17.5-30.4) and 23.2 per 100?000 (95% CI 6.6-39.7), respectively. Across both registries, incidence rates increased considerably between 2000 and 2015.The available evidence suggests a growing incidence of breast cancer in Africa. The representativeness of these estimates is uncertain due to the paucity of data in several countries and calendar years, as well as inconsistency in data collation and quality across existing cancer registries.

SUBMITTER: Adeloye D

PROVIDER: S-EPMC5903682 | biostudies-other | 2018 Jun

REPOSITORIES: biostudies-other

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Estimating the incidence of breast cancer in Africa: a systematic review and meta-analysis.

Adeloye Davies D Sowunmi Olaperi Y OY Jacobs Wura W David Rotimi A RA Adeosun Adeyemi A AA Amuta Ann O AO Misra Sanjay S Gadanya Muktar M Auta Asa A Harhay Michael O MO Chan Kit Yee KY

Journal of global health 20180601 1

<h4>Background</h4>Breast cancer is estimated to be the most common cancer worldwide. We sought to assemble publicly available data from Africa to provide estimates of the incidence of breast cancer on the continent.<h4>Methods</h4>A systematic search of Medline, EMBASE, Global Health and African Journals Online (AJOL) was conducted. We included population- or hospital-based registry studies on breast cancer conducted in Africa, and providing estimates of the crude incidence of breast cancer amo ...[more]

PMID: 29740502

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Project description:BACKGROUND:The incidence of breast cancer in sub-Saharan Africa is relatively low, but as survival from the disease in the region is poor, mortality rates are as high as in high-income countries. Stage at diagnosis is a major contributing factor to poor survival from breast cancer. We aimed to do a systematic review and meta-analysis on stage at diagnosis of breast cancer in sub-Saharan Africa to examine trends over time, and investigate sources of variations across the region. METHODS:We searched MEDLINE, Embase, Web of Knowledge, and Africa-Wide Information to identify studies on breast cancer stage at diagnosis in sub-Saharan African women published before Jan 1, 2014, and in any language. Random-effects meta-analyses were done to investigate between-study heterogeneity in percentage of late-stage breast cancer (stage III/IV), and meta-regression analyses to identify potential sources of variation. Percentages of women with late-stage breast cancer at diagnosis in sub-Saharan Africa were compared with similar estimates for black and white women in the USA from the Surveillance, Epidemiology, and End Results database. FINDINGS:83 studies were included, which consisted of 26?788 women from 17 sub-Saharan African countries. There was wide between-study heterogeneity in the percentage of late-stage disease at diagnosis (median 74·7%, range 30·3-100%, I2=93·3%, p<0·0001). The percentage of patients with late-stage disease at diagnosis did not vary by region in black women, but was lower in non-black women from southern Africa than in black women in any region (absolute difference [AD] from black women in western Africa [reference group] -18·1%, 95% CI -28·2 to -8·0), and higher for populations from mixed (urban and rural) settings rather than urban settings (13·2%, 5·7 to 20·7, in analyses restricted to black women). The percentage of patients with late-stage disease at diagnosis in black Africans decreased over time (-10·5%, -19·3 to -1·6; for 2000 or later vs 1980 or before), but it was still higher around 2010 than it was in white and black women in the USA 40 years previously. INTERPRETATION:Strategies for early diagnosis of breast cancer should be regarded as a major priority by cancer control programmes in sub-Saharan Africa. FUNDING:None.

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Project description:IntroductionThere are no data summarising the epidemiology of pulmonary hypertension (PH) among adults residing in Africa. Establishment of accurate epidemiological data on PH in this region may guide decision-making toward interventions to curb the burden of PH in Africa. The aim of this systematic review is to determine the prevalence, incidence and aetiologies of PH among people residing in Africa.Methods and analysisThis systematic review and meta-analysis will follow the MOOSE guidelines for reporting. Relevant abstracts published until 30 September 2016 will be searched in PubMed/Medline, EMBASE (Excerpta Medica Database), African Journals Online and Africa Index Medicus. Full texts of eligible studies will then be accessed through PubMed, Google Scholar, HINARI and the respective journals' websites. Relevant unpublished papers and conference proceedings will also be checked. Data will be analysed using STATA version 13 software. The study-specific estimates will be pooled through a random-effects meta-analysis model to obtain an overall summary estimate of the prevalence/incidence and aetiologies of PH across studies. Heterogeneity of studies will be evaluated by the ?2 test on Cochrane's Q statistic. Funnel plot analysis and Egger's test will be done to detect publication bias. Results will be presented by geographical region (central, eastern, northern, southern and western Africa).Ethics and disseminationThe current study is based on published data; ethical approval is, therefore, not required. This review will guide policy, practice and research by providing information on the magnitude of PH among people residing in Africa. Findings will be presented in evidence tables of individual studies as well as in summary tables. The final report of this systematic review, in the form of a scientific paper, will be published in a peer-reviewed journal. Furthermore, findings will be presented at conferences and submitted to relevant health authorities.Review registration numberPROSPERO CRD42016049351.

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Estimating the incidence of breast cancer in Africa: a systematic review and meta-analysis.

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Estimating the incidence of breast cancer in Africa: a systematic review and meta-analysis.

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