How advanced is breast cancer in Africa?
Breast cancer is a growing problem in low-resource settings. According to the GLOBOCAN database,
an estimated 94 378 new cases of breast cancer are diagnosed in sub-Saharan Africa annually. Incidence rates vary considerably between African countries—eg, 38 new cases per 100 000 women per year in Kenya compared with 28 cases per 100 000 women per year in Uganda. An average increase in incidence rate of 3·7 cases per 100 000 women per year was seen in the past 20 years in Uganda.
The Concord study group has published survival data from individual patients from 279 population-based registries in 67 countries worldwide. Outcomes vary greatly between regions and improvements in survival were seen over time. The outcome was dependent on early diagnosis and access to therapy.
Findings from hospital-based studies suggest that patients who actually receive therapy can have a good outcome; one such study from Ethiopia
reported a distant metastasis survival rate of 74% after 2 years.
Patients with breast cancer in Africa are often thought of as being young and presenting at a late stage of the disease. In The Lancet Global Health, Elima Jedy-Agba and colleagues
present the first comprehensive systematic review and meta-analysis of breast cancer stage at diagnosis in sub-Saharan Africa. The authors included 83 studies with 26 788 individuals. Most results were from consecutive or convenience case series at tertiary hospitals, an important source of information for health-care planning. Notably, the percentage of patients with late-stage (stage III/IV) cancer varied greatly between studies, ranging from 30% in South Africa to nearly 98% in one Nigerian study. The meta-regression analysis revealed that urban populations and non-black South African populations had lower percentages of patients with late-stage breast cancer at diagnosis than black or mixed ethnic South African patients and those from rural or rural and urban backgrounds. Readers might have expected age, region, or type of health facility to affect the percentage of women with late-stage breast cancer, but no differences were seen. Information about late-stage breast cancer from a population-based cancer registry would be useful to account for the selection bias of hospitals. Population-based data showed that 74% of women in Côte d’Ivoire and 81% of women in Democratic Republic of the Congo had late-stage breast cancer in 2008–09.
Jedy-Agba and colleagues also report that the average age at diagnosis in sub-Saharan Africa (35–49 years) is lower than in high-income countries, which is due to the high proportion of young people in these countries. Others have shown that age-specific incidence rates in young age groups in Africa do not differ when compared with European countries.
These findings are evidence against the theory of a unique highly aggressive form of breast cancer in Africa. However, some differences in tumour biology or genetics have been described in studies comparing African-American patients with white patients, which showed a slightly earlier onset of the disease and adverse outcome in African-American patients after adjusting for known adverse prognostic factors.
These other known prognostic factors were not presented in most of the African papers and were therefore not reviewed by Jedy-Agba and colleagues.
Trained volunteers and health-care workers have been shown to be able to do simplified screening to find advanced breast cancer at a village level.
The need for patient advocates, such as survivors, and education of health-care workers to correctly help women with symptoms of breast cancer is evident. Their success will depend on the assurance of diagnosis and the availability of appropriate treatment. Pathology resources have to be sustainably developed across sub-Saharan Africa.
Palliative care for patients with late-stage breast cancer is much needed because the risk of metastasis in these patients is high. The financial burden for the average patient with breast cancer in sub-Saharan Africa should also be considered in strategies to improve early diagnosis.