Rising global burden of breast cancer: the case of sub-Saharan Africa (with emphasis on Nigeria) and implications for regional development: a review

Abstract

Background: Despite mortality from breast cancer in Africa being higher than in high income countries, breast cancer has not been extensively studied in the region. The aim of this paper was to highlight the rising burden of breast cancer with an emphasis on sub-Saharan Africa as well as trends, characteristics, controversies and their implications for regional development.

Methodology: A review of published studies and documents was conducted in Medline, Scopus, Pubmed and Google using combinations of key words-breast neoplasm, breast cancer, cancer, incidence, mortality, Africa, Nigeria. Graphical and frequency analyses were carried out on some of the incidence and mortality figures retrieved from published papers and the GLOBOCAN website.

Findings: Globally, about 25% and 15% of all new cancer cases and cancer deaths respectively among females were due to breast cancer. Africa currently had the highest age-standardized breast cancer mortality rate globally, with the highest incidence rates being recorded within the sub-Saharan African sub-region. Incidence trends such as inherently aggressive tumour and younger age profile had been subject to controversies. Certain factors such as westernized diet, urbanization and possibly increasing awareness had been implicated, though their specific contributions were yet to be fully established.

Conclusion: Unless urgent action is taken, breast cancer will compound sub-Saharan Africa's disease burden, increase poverty and gender inequality as well as reverse the current global gains against maternal and neonatal mortality.

Keywords: Africa; Breast cancer; Incidence; Mortality; Nigeria.

Fig. 1

Diagrammatic explanation of data extraction process

Fig. 2

Global burden of breast cancer by continents (per 100,000 women per year)(based on Ferlay et al. [8]). Figure 2 was based on seven continent model [65]. Central America and Caribbean were grouped under northern America, while New Zealand, Polynesia and Micronesia were grouped under Australia. It showed that while continent of Europe had the highest ASR incidence rate, Africa had the highest ASR mortality rate. This may differ slightly when analysis is based on United Nation’s world areas shown

Fig. 3

Breast Cancer Burden by United Nations world areas. The figure shows that while northern America has the highest incidence rate, western Africa has the highest mortality rate

Fig. 4

a Distribution of breast cancer incidence and mortality in Africa (based on GLOBOCAN, 2012). b Map of Africa showing distribution of age-standardized incidence rates by countries. c Map of Africa showing distribution of age-standardized mortality rates by countries

Fig. 5

Increasing incidence of breast cancer in Nigeria since 1960 (based on Jeddy Egba etal [38] and GLOBOCAN, 2012 [12]

Fig. 6

Top 20 countries with the highest incidence and Mortality associated with breast cancer in Africa

Fig. 7

Map of Africa showing sub-Saharan Africa (countries below the grey area). (Source: https://www.librarything.com/topic/183039)