Year : 2013 | Volume
: 12 | Issue : 1 | Page : 57--58
Breast cancer outcome in African women: If different, how different, why different?
Robert B Sanda
Department of Surgery, Drumheller Hospital, Drumheller, Alberta, Canada
Robert B Sanda
Department of Surgery, Drumheller Hospital, Drumheller, Alberta
|How to cite this article:|
Sanda RB. Breast cancer outcome in African women: If different, how different, why different?.Ann Afr Med 2013;12:57-58
|How to cite this URL:|
Sanda RB. Breast cancer outcome in African women: If different, how different, why different?. Ann Afr Med [serial online] 2013 [cited 2023 Jun 1 ];12:57-58
Available from: https://www.annalsafrmed.org/text.asp?2013/12/1/57/108258
Diseases that have single known etiologic factors are those that are amenable to ease of diagnosis, treatment, and prevention. With diseases of indeterminate or multifactorial etiology clinical challenges are considerable. Treatment options and results are often constrained by the different therapeutic contingencies that result in heterogeneous treatment outcomes. This is the case with breast cancer.
The work of Sir Geoffrey Keynes  in the 1930s and that of Bernard Fisher , and others  beginning in the 1970s brought to light the limitation of aggressive surgical excision as an effective treatment and forced on the thinking of breast cancer as a systemic disease from early in its evolution and paved the way for systemic therapy to complement local therapy. This pioneering thought compelled us to appreciate that breast cancer cells are adaptable through clonal selection with tumor progression. They attain this status by genetic and epigenetic alterations to ensure their parasitic survival at the expense of the host. Chemotherapy and endocrine modulation have been employed in oncology by taking advantage of the biologic characteristics of the tumors, particularly their expression of receptors for growth factors. , In parts of the world where the greatest advancements have been made in the treatment of breast cancer over the years, researchers have taken advantage of available funding and their rich database of patients to review and compare treatment results to promote or demote each option of treatment. The recent withdrawal of the Food and Drug Administration (FDA)-approval of the drug Bevacizumab (Avastin) in the treatment of breast cancer is a case in point.
In sub-Saharan Africa where the disease is less common but more deadly due to a combination of social factors that keep patients away from modern medicine at a stage where the disease is at its most treatable and government inability to establish health institutions capable of rendering optimal treatment for the women so afflicted, clinicians are compelled to rely on publications from developed countries with data from a different population group. This may work for the majority of patients but even if only a minority of patients differ in certain biological parameters from their contemporaries from which these treatment recommendations were drawn, there is a chance that this subset of patients may be harmed through the use of inappropriate or ineffective treatment for their types of cancer.
The observation that a significant difference in the incidence rate of breast cancer exists between women in Africa, the Middle East, Asia, South America on the one hand and their counterparts in Europe, Oceania, and North America on the other has not been adequately explained. The World Health Organization estimates that this difference is up to a magnitude of a factor of four.  Since the majority of women in the latter regions share a common Caucasian ancestry and since these territories account for the vast majority of the developed nations of the world and since life expectancy is significantly higher, the confusion of whether this difference in susceptibility is due to genetic or environmental factors is not easy to understand.
Temporal trends suggest that breast cancer incidence in industrialized countries increased sharply from the mid-1980s onwards, a fact that some observers have attributed to the introduction of mammography and cancer screening programs in these same countries. Similarly, breast cancer mortality rate seems to have decreased shortly thereafter. Statisticians have been quick to point out that this decline in mortality specific to breast cancer is probably due in part to the fact that the pool of breast cancer has been diluted by preclinical stages of the disease as well as the inclusion of nonfatal forms of cancer that are picked up during the screening process in addition to newer modalities of treatment. It probably will take another decade or two before we can confidently say that the changes noted in breast cancer incidence in Caucasian women in recent decades has not been due to a lead-time bias.
Women in Africa, while enjoying the advantage of a lower incidence rate, cannot lay claim to equal access to quality care as their counterparts in North America or Europe. In this part of the world, delay in initial presentation, absence of national cancer screening programs, limitation of diagnostic and treatment options, and the cultural penchant to resort to alternative medicine to incur further delay in starting treatment all lead to a poor survival rates.
The finding of poor expression of hormone receptors and high tumor grades in the majority of specimens from Nigerian women in an international collaborative study published in this edition of the journal has important implications.  Before discarding our oars in celebration we need to replicate this interesting observation qualitatively and quantitatively. A multicenter, prospective randomized study that seeks not only to describe the problem but also the long-term survival differences is called for. The problem of funding can be surmounted by institutions, the federal ministries of health as well as the ministry of science and technology in addition to state governments and private institutions in lending financial support to academic and research institutions where these patients are treated just as is done in the developed world.
|1||Keynes G. Conservation treatment of cancer of the breast. BMJ 1937;2:643-7.|
|2||Fisher B, Carbone P, Economou SG, Frelick R, Glass A, Lerner H, et al. L-Phenylalanine mustard in the management of primary breast cancer - a report of early findings. N Engl J Med 1975;292:117-22.|
|3||Fisher B, Redmond C, Fisher ER, Bauer M, Wolmark N, Wickerham DL, et al. Ten-year results of a randomized clinical trial comparing radical mastectomy and total mastectomy with or without radiation. N Engl J Med 1985;312:674-81.|
|4||Bonadonna G, Brusamolino E, Valagussa P, Rossi A, Brugnatelli L, Brambilla C, et al. Combination of chemotherapy as an adjuvant treatment in operable breast cancer. N Engl J Med 1976;294:405-10.|
|5||Lindeman GJ, Visvader JE. Insights into the cell of origin in breast cancer and breast cancer stem cells. Asia Pac J Clin Oncol 2010;6:89-97.|
|6||Iwasa Y, Michor F. Evolutionary dynamics of intratumor heterogeneity. PLoS One 2011;6:e17866.|
|7||Boyle P, Levin B. World cancer report 2008. Lyons: IARC; 2008. p. 413-7.|
|8||Adisa CA, Eleweke N, Alfred AA, Campbell MJ, Sharma R, Nseyo O, et al. Biology of breast cancer in Nigerian women: A pilot study. Ann Afr Med 2011;11:169-75.|