Immunohistochemical and molecular subtypes of breast cancer in Nigeria

Regulatory and therapeutic implications of competing endogenous RNA network in breast cancer progression and metastasis: A review

Breast cancer (BC) is a global health concern, and development of diagnostic tools and targeted treatments for BC remains challenging. Therapeutic approaches for BC often involve a combination of surgery, radiation therapy, chemotherapy, targeted therapy, and hormone therapy. In recent years, there has been a growing interest in the role of noncoding RNAs (ncRNAs), including long ncRNAs (lncRNAs) and microRNAs (miRNAs), in BC and their therapeutic implications. Various biological processes such as cell proliferation, migration, and apoptosis rely on the activities of these ncRNAs, and their dysregulation has been implicated in BC progression. The regulatory function of the competitive endogenous RNA (ceRNA) network, which comprises lncRNAs, miRNAs, and mRNAs, has been the subject of extensive pathophysiological research. Most lncRNAs serve as molecular sponges for miRNAs and sequester their activities, thereby regulating the expression of target mRNAs and contributing to the promotion or inhibition of BC progression. This review summarizes recent findings on the role of ceRNA networks in BC progression, metastasis, and therapeutic resistance, and highlights the association of ceRNA networks with transcription factors and signaling pathways. Understanding the ceRNA network can lead to the discovery of biomarkers and targeted treatment methods to prevent the spread and metastasis of BC.

Discordance between PAM50 intrinsic subtyping and immunohistochemistry in South African women with breast cancer

PURPOSE

Breast cancer is a heterogeneous disease with different gene expression profiles, treatment options and outcomes. In South Africa, tumors are classified using immunohistochemistry. In high-income countries multiparameter genomic assays are being utilized with implications for tumor classification and treatment.

METHODS

In a cohort of 378 breast cancer patients from the SABCHO study, we investigated the concordance between tumor samples classified by IHC and the PAM50 gene assay.

RESULTS

IHC classified patients as ER-positive (77.5%), PR-positive (70.6%), and HER2-positive (32.3%). These results, together with Ki67, were used as surrogates for intrinsic subtyping, and showed 6.9% IHC-A-clinical, 72.7% IHC-B-clinical, 5.3% IHC-HER2-clinical and 15.1% triple negative cancer (TNC). Typing using the PAM50 gave 19.3% luminal-A, 32.5% luminal-B, 23.5% HER2-enriched and 24.6% basal-like. The basal-like and TNC had the highest concordance, while the luminal-A and IHC-A group had the lowest concordance. By altering the cutoff for Ki67, and realigning the HER2/ER/PR-positive patients to IHC-HER2, we improved concordance with the intrinsic subtypes.

CONCLUSION

We suggest that the Ki67 be changed to a cutoff of 20-25% in our population to better reflect the luminal subtype classifications. This change would inform treatment options for breast cancer patients in settings where genomic assays are unaffordable.

Nanoindentation study of the viscoelastic properties of human triple negative breast cancer tissues: Implications for mechanical biomarkers

This paper presents the results of a combined experimental and theoretical study of the structure and viscoelastic properties of human non-tumorigenic mammary breast tissues and triple negative breast cancer (TNBC) tissues of different histological grades. A combination of immunofluorescence and confocal microscopy, and atomic force microscopy is used to study the actin cytoskeletal structures of non-tumorigenic and tumorigenic breast tissues (grade I to grade III). A combination of nanoindentation and statistical techniques is then used to measure viscoelastic properties of non-tumorigenic and human TNBC of different histological grades. A Standard Fluid Model/Anti-Zener Model II is also used to characterize the viscoelastic properties of the non-tumorigenic and tumorigenic TNBC tissues of different grades. The implications of the results are discussed for the potential application of nanoindentation and statistical deconvolution techniques to the development of mechanical biomarkers for TNBC detection/cancer diagnosis. STATEMENT OF SIGNIFICANCE: There is increasing interest in the development of mechanical biomarkers for cancer diagnosis. Here, we show that nanoindentation techniques can be used to characterize the viscoelastic properties of normal breast tissue and TNBC tissues of different histological grades. The Standard Fluid Model (Anti-Zener Model II) is used to classify the viscoelastic properties of breast tissues of different TNBC histological grades. Our results suggest that breast tissue and TNBC tissue viscoelastic properties can be used as mechanical biomarkers for the detection of TNBC at different stages.

Adhesion of LHRH/EphA2 to human Triple Negative Breast Cancer tissues

The adhesive interactions between molecular recognition units (such as specific peptides and antibodies) and antigens or other receptors on the surfaces of tumors are of great value in the design of targeted nanoparticles and drugs for the detection and treatment of specific cancers. In this paper, we present the results of a combined experimental and theoretical study of the adhesion between Luteinizing Hormone Releasing Hormone (LHRH)/Epherin type A2 (EphA2)-AFM coated tips and LHRH/EphA2 receptors that are overexpressed on the surfaces of human Triple Negative Breast Cancer (TNBC) tissues of different histological grades. Following a histochemical and immuno-histological study of human tissue extracts, the receptor overexpression, and their distributions are characterized using Immunohistochemistry (IHC), Immunofluorescence (IF), and a combination of fluorescence microscopy and confocal microscopy. The adhesion forces between LHRH or EphA2 and human TNBC breast tissues are measured using force microscopy techniques that account for the potential effects of capillary forces due to the presence of water vapor. The corresponding adhesion energies are also determined using adhesion theory. The pull off forces and adhesion energies associated with higher grades of TNBC are shown to be greater than those associated with normal/non-tumorigenic human breast tissues, which were studied as controls. The observed increase in adhesion forces and adhesion energies are also correlated with the increasing incidence of LHRH/EphA2 receptors at higher grades of TNBC. The implications of the results are discussed for the development of targeted nanostructures for the detection and treatment of TNBC.

Pharmacogenetics of Breast Cancer Treatments: A Sub-Saharan Africa Perspective

Breast cancer is the most frequent cause of cancer death in low- and middle-income countries, in particular among sub-Saharan African women, where response to available anticancer treatment therapy is often limited by the recurrent breast tumours and metastasis, ultimately resulting in decreased overall survival rate. This can also be attributed to African genomes that contain more variation than those from other parts of the world. The purpose of this review is to summarize published evidence on pharmacogenetic and pharmacokinetic aspects related to specific available treatments and the known genetic variabilities associated with metabolism and/or transport of breast cancer drugs, and treatment outcomes when possible. The emphasis is on the African genetic variation and focuses on the genes with the highest strength of evidence, with a close look on CYP2A6, CYP2B6, CYP2C8, CYP2C9, CYP2C19, CYP2D6, CYP3A4/5, CYP19A1, UGT1A4, UGT2B7, UGT2B15, SLC22A16, SLC38A7, FcγR, DPYD, ABCB1, and SULT1A1, which are the genes known to play major roles in the metabolism and/or elimination of the respective anti-breast cancer drugs given to the patients. The genetic variability of their metabolism could be associated with different metabolic phenotypes that may cause reduced patients' adherence because of toxicity or sub-therapeutic doses. Finally, this knowledge enhances possible personalized treatment approaches, with the possibility of improving survival outcomes in patients with breast cancer.

The African Female Breast Cancer Epidemiology Study Protocol

Breast cancer is now the commonest cancer in most sub-Saharan African countries. Few studies of the epidemiology and genomics of breast cancer and its molecular subtypes in these countries have been done. The African Female Breast Cancer Epidemiology (AFBRECANE) study, a part of the Human Heredity and Health in Africa (H3Africa) initiative, is designed to study the genomics and epidemiology of breast cancer and its molecular subtypes in Nigerian women. We link recruitment of breast cancer cases at study sites with population-based cancer registries activities to enable ascertainment of the incidence of breast cancer and its molecular subtypes. We use centralized laboratory processing to characterize the histopathological and molecular diagnosis of breast cancer and its subtypes using multiple technologies. By combining genome-wide association study (GWAS) data from this study with that generated from 12,000 women participating in our prospective cohort study of cervical cancer, we conduct GWAS of breast cancer in an entirely indigenous African population. We test associations between dietary intakes and breast cancer and focus on vitamin D which we measure using dietary intakes, serum vitamin D, and Mendelian randomization. This paper describes the AFBRECANE project, its design, objectives and anticipated contributions to knowledge and understanding of breast cancer.

Survival and Predictors of Mortality among Breast Cancer Patients in Northwest Ethiopia: A Retrospective Cohort Study

BACKGROUND

Breast cancer is the most common malignant tumor and the leading cause of cancer death in over 100 countries. Despite the high burden of difficulty, the survival status and the predictors for mortality are not yet determined in Ethiopia. Studies related to this area are scarce. Therefore, we aimed to estimate the survival status and predictors of mortality among breast cancer patients in Northwest Ethiopia.

METHODS

A retrospective cohort study design was carried out from September 2015 to August 2020 among 482 women who had breast cancer in Northwest Ethiopia. A systematic sampling technique was employed to select the required representative sample. The Cox regression model was used to identify the predictors of mortality among breast cancer patients.

RESULTS

For this study, 482 participants had followed for 8824 person-months total analysis time or at-risk time. In our findings, the overall survival of breast cancer patients at the end of two and five years was 54.24% and 25.8%, respectively. In the multivariable Cox regression model, age, stage of BC, menopausal status, and surgical therapy were significant predictors of death.

CONCLUSION

The overall survival after two years was 54.24%, and after five years was 25.8%. This result is lower than the recently published report and indicates that in LMIC, especially in rural cancer centers, the infrastructure and resources for routine screening mammography are often unavailable. Therefore, there is a need to promote early diagnosis of BC at each level of health-care delivery point.

Hormone Receptors and Her-2/neu Overexpression in Breast Carcinomas in Patients of West African Origin Seen at Lagos State University Teaching Hospital, Nigeria

Breast carcinoma is a disease of utmost concern to the individual, family, and society at large. The current trend in the management of breast carcinoma also involves hormonal therapy. Consequently, the hormone expression of the tumor in the individual involved must be known if he or she is to benefit from such therapy. This is a prospective study of estrogen and progesterone receptors as well as Her-2/neu overexpression in all breast carcinomas seen at the Lagos State University Teaching Hospital, Ikeja, Nigeria, between April, 1, 2016, and September, 30, 2018. The total number of cases analyzed during the period under study was 107, comprising 105 women and 2 men with an age range of 26 to 88 years and a mean age of 52 ± 13 years. The tumors fell into histologic grade II (71.0%) and grade III (29.0%). They expressed ER, PR, and Her-2/neu positivity in 42.1%, 33.6%, and 30.8% of the cases, respectively. Triple-negative breast cancer was 35.5%. Male breast cancers presented as invasive ductal carcinoma and exhibit similar staining pattern as the female breast cancer. In conclusion, this study shows that breast carcinomas occurred predominantly in females of younger age and present with tumors, most of which were of high grade and exhibit triple negativity. This observation is relevant to any therapeutic decisions and management of these patients. Improvement in breast carcinoma screening programs so that the disease can be detected early is also advocated.

Predictive and prognostic relevance of immunohistochemical testing of estrogen and progesterone receptors in breast cancer in South East Nigeria: A review of 417 cases

ER/PgR testing are now routinely performed in breast cancer evaluation in Southeastern Nigeria. ER is predictive to show beneficiaries of hormonal therapy and a prognostic marker to establish tumors that will resist paclitaxel induced apoptosis so a cost effective combination of anthracylines can be used as treatment in our low resource setting thus improving survival, reducing recurrence, and cost. Four hundred seventeen cases of breast cancer seen over a period of 3 years were routinely tested for ER/PgR. ER positivity was defined as nuclear positivity of 1% in the presence of internal and external controls. Four hundred seventeen patients with Ductal Carcinoma participated. Majority were females 98.3%. Majority 60.2% were between 31 and 50 years old. Mean age was 33.5 ± 6.4 years. Two hundred fifty-seven (61.6%) were positive both for ER/PgR. 70.3% of age group 41–50 years had positive ER, age groups 20–30, and >70 years had positive ER also. ER positive cancer was 60.2%. Fifty-seven were 1%–9% positive. Most positive estrogen receptors were seen between 41 and 50 years at 70.3%. Least was seen at 31–40 years at 51.4%. Study provides an objective basis for using hormonal manipulation and makes cost affordable with appropriate chemotherapeutic agents in our low resource setting. Presentations were typically late. Seventy-six percent of stage 2 disease survived after 6 years compared with only 56% of stage 2 disease prior to immunotyping and radiotherapy in 2007. Both stage 3 and 4 had remarkable survival too at 55% and 33% respectively when compared with 2007 figures at 33% for stage 3 and 9.2% at stage 4.

Adherence to endocrine therapy and its relation to disease-free survival among breast cancer patients visiting an out-patient clinic at Khartoum Oncology Hospital, Sudan

RATIONALE

Adherence to endocrine therapy provides substantial reduction in breast cancer (BC) relapses and improve survival. Hence, non-adherence remains an under reported issue mainly in developing countries.

AIMS AND OBJECTIVES

The aim of this study is to evaluate the adherence to endocrine therapy (tamoxifen [TAM] and aromatase inhibitors [AIs]) among BC patients visiting an out-patient clinic (2015-2016) in Khartoum Oncology Hospital, Sudan.

METHODS

Adherence was assessed using pills count and self-reporting methods. A total of 172 patients were interviewed. Also, records were reviewed for demographic and other cancer characteristics.

RESULTS

The patients' mean age at diagnosis was 53 years, with the highest frequency at (41-60) years. Invasive ductal carcinoma 69.2% formed the main pathological diagnosis. T2 tumour size (51.2%) and lymph node involvement (N1) (31.4%) were most evident. Also, the majority of patients were stage III (45.9%) and grade II (48%). The studied women were postmenopausal (49.4%) and premenopausal (47.7%). Regarding hormonal receptors, about 68% were oestrogen (ER)+/progesterone (PR)+ and 23.3% were ER+/PR-. Studying adherence, almost (93%) of the studied group were ≥80% adherent to TAM and AIs. The hormonal therapy persistence mean was 27.2 ± 22.5 months (40-96). While adherence percentage mean was 93.7 ± 13.6% (0%-100%). Also disease-free survival (DFS) mean was 36.3 ± 32.7 months (4-312). Adherence to hormonal therapy and persistence were significantly correlated (P < .000). Also, statistically significant association was found between hormonal therapy adherence (≥80%) and patient poor to average economic status (P = .006), and the marital status "married" (P = .008).

CONCLUSIONS

A high rate of adherence (93%) to endocrine therapy was estimated in the present study. Also, a positive association was found between the hormonal therapy persistence, and the DFS year's groups (P = .000), and the hormonal therapy types (P = .000). Adherence to hormonal therapy and persistence were significantly correlated (P < .000).

Breast Cancer and Tamoxifen: A Nigerian Perspective to Effective Personalised Therapy

Estrogen-receptor positivity in tumour, often requiring long-term tamoxifen therapy, is thought to characterise between 43% and 65% of breast cancer cases in Nigeria. The patient population is further marked by late-stage diagnosis which significantly heightens the tendency for tumour relapse in the course of tamoxifen therapy. Despite tamoxifen being considered a reliable chemopreventive in high-risk individuals and an effective adjuvant therapy for hormone-sensitive tumours, mortality has remained high among breast cancer patients in the West African region where Nigeria belongs. The Nigerian breast cancer population, like other similar patient-populations in the West African region, provides a mix of intrinsic genome-diversity and perhaps unique tumour biology and evolution. These peculiarities suggest the need for a rational approach to tumour management and a personalised delivery of therapy in Nigeria's dominant estrogen-receptor-positive patient population. Herein, critical indices of tamoxifen-therapy success are discussed in the context of the Nigerian breast cancer population with emphasis on salient aspects of tamoxifen-biotransformation, host- and tumour-genomics, and epigenetics.

Impact of axillary node-positivity and surgical resection margins on survival of women treated for breast cancer in Ibadan, Nigeria

Introduction

Oncologic surgical extirpation, the mainstay of loco-regional disease control in breast cancer, is aimed at achieving negative margins and lymph node clearance. Even though axillary lymph nodal metastasis is a critical index of prognostication, establishing the impact of lymph node ratio (LNR) and adequate surgical margins on disease-specific survivorship would be key to achieving longer survival. This study examines the prognostic role of pN (lymph nodes positive for malignancy), LNR and resection margin on breast cancer survival in a tertiary hospital in Ibadan, Nigeria.

Methods

We conducted a longitudinal cohort study of 225 patients with breast carcinoma, documented clinico-pathologic parameters and 5-year follow up outcomes - distant metastasis and survival. Chi-square test and logistic regression analysis were used to evaluate the interaction of resection margin and proportion of metastatic lymph nodes with patients' survival. The receiver operating characteristic curve was plotted to determine the proportion of metastatic lymph nodes which predicted survival. The survival analysis was done using Kaplan-Meier method.

Results

Sixty (26.7%) patients of the patients had positive resection margins, with the most common immuno-histochemical type being Lumina A. 110 (49%) patients had more than 10 axillary lymph nodes harvested. The mean age was 48.6 ± 11.8 years. Tumour size (p = 0.018), histological type (p = 0.015), grade (p = 0.006), resection margin (p = 0.023), number of harvested nodes (p < 0.01), number of metastatic nodes (p < 0.001) and loco-regional recurrence (p < 0.01) are associated with survival. The overall 5-year survival was 65.3%.

Conclusion

Unfavourable survival outcomes following breast cancer treatment is multifactorial, including the challenges faced in the multimodal treatment protocol received by our patients.

Panoptic Overview of Triple-Negative Breast Cancer in Nigeria: Current Challenges and Promising Global Initiatives

Purpose

Triple-negative breast cancer (TNBC) is the most deadly form of breast cancer (BC) today. TNBC treatment is fraught with challenges because of the extensive interpatient heterogeneity in clinical behavior and scarcity of stratifying biomarkers and actionable targets. Women of African ancestry face a disproportionate burden resulting from this disease, which affects them earlier and more aggressively and has a higher propensity to spread and resist conventional treatments. A much higher proportion of Nigerian patients with BC have TNBC compared with patients with BC in the United States and Europe.

Methods

This article spotlights Nigeria as an example of a nation wherein genetic and nongenetic spheres of influence intersect to affect the prevalence of this disease, the scale of its challenge, and its toll.

Results

Studies have illuminated the inherently different tumor biology of Nigerian TNBCs, which show distinct genetic variants and gene expression patterns compared with European or European-American TNBCs. Parallels are apparent between TNBC phenotypes among African Americans and Nigerians, implicating the common thread of shared genetic ancestry between these populations. Reproductive, lifestyle, socioeconomic, and cultural factors also shape TNBC outcomes in Nigeria, as do resource constraints in Nigerian health care and research sectors.

Conclusion

Increasing our understanding of how these factors contribute to poorer outcomes among Nigerian women may uncover valuable insights and strategies in alleviating the TNBC burden in many countries of the world and help reduce the racial disparity in BC-related outcomes here in the United States. Importantly, this review also highlights collaborative global and local initiatives that converge expertise and resources to advance research on effective management of TNBC in diverse populations.

Outcome of Cerebral Metastasectomy in Select Cases of Brain Metastases from Breast Cancer in Ibadan, Nigeria

BACKGROUND

Brain metastasis (BM) from breast cancer is increasingly encountered clinically because of the continuing success in the oncological control of the primary disease. Data-driven reports on the surgical treatment of BM from breast cancer are sparse in sub-Saharan Africa.

METHODS

This is a prospective cohort study of the outcome of surgical excision of BM from breast cancer in an academic surgical practice in Ibadan, Nigeria.

RESULTS

A total of 12 consecutive cerebral metastasectomies, all in females with primary breast cancer, were recorded over the study period. The median age (range) at breast cancer diagnosis was 41 (27-72) years, and the time interval from primary disease to BM was 19 (12-29) months. The BM was the first site of systemic disease progression in all, and was heralded by headache, seizures, and hemiparesis in more than two-thirds of the patients. The brain lesions were multiple in a quarter: >4 cm large in 42% and were located supratentorial in >80%. They all achieved good recovery and in-hospital outcome after surgical lesionectomy-infra- and supratentorial craniotomies-but only two-thirds could access postsurgical adjuvant whole brain radiation therapy. Median survival after cerebral metastasectomy was 18 (11-55) months, and more than a quarter were alive for ≥3years. These survival statistics were significantly better than those of a contemporary cohort of our patients with breast cancer who also had BMs that were not surgically treated for various clinical and logistic limitations.

CONCLUSIONS

Surgical resection is feasible for BM from breast cancer even in low-resource clinical practice. It has a salutary effect on the patients' quality of life.

Molecular profile of breast cancers in Guinean oncological settings

Breast cancer is a complex disease characterized by the accumulation of multiple molecular alterations giving each tumor phenotype and an own evolutionary potential. This study aimed to describe the distribution of the profile and molecular subtypes of breast cancers followed at Surgical Oncology Unit of Donka National Hospital. This was retrospective and descriptive study on cases of breast cancer in which the hormone receptor status and expression of the Her2 oncogene have been performed from 2007 to 2016. We recorded 58 cases including 56 (96.6%) women and 2 (3.4%) men. The average age was 48.2 ± 10.9. Invasive ductal carcinoma accounted for 50 (86.2%) cases. The SBR grade was II in 31(53.4%) cases, III in 21 (36.2%) cases and I in 6 (10.3%) cases. The tumor was classified as T4 in 36 (62.1%) cases; it was metastatic in 11(19.0%) cases. Estrogen receptors were positive in 29 (50.0%) cases, progesterone receptors positive in 25 (43.1%) cases, the Her2 oncogene was positive in 22 (39.3%) cases. The distribution of molecular sub-types was: 20 (34.5%) luminal A, 15 (25.9%) triple negative, 13 (22.4%) Her2 overexpressed, 8 (13.8%) luminal B and 2 (3.2%) undetermined. This preliminary study showed the poor accessibility of immunohistochemistry for the molecular diagnosis of breast cancer in our country. Luminal A subtypes and triple negatives were more common. The determination of molecular subtypes is a rational basis for hormone therapy and targeted therapy, thus personalizing the treatment of breast cancer.

Subtypes of Breast Cancer in Lao P.D.R.: A Study in a Limited-Resource Setting

Aim:

The purpose of this study is to evaluate the prevalence of the immunohistochemical subtypes of breast cancer among Lao women by using immunohistochemistry (according to the St. Gallen 2017 guidelines) and to study their correlation to clinicopathological features in order to help guide better treatment plans for patients.

Materials and methods:

Formalin-fixed and paraffin embedded tissue blocks of 76 cases of primary invasive breast cancer were retrieved from the University of Health Sciences, Vientiane, Lao PDR, from 2013 to 2016. Patients’ information and previous histological reports were reviewed. Immunohistochemistry was done using antibodies against estrogen receptor (ER), progesterone receptor (PR), human epidermal growth factor receptor 2 (HER2/neu) and Ki-67 (MIB-1).

Results:

The mean age of the patients was 49 years, and the major histologic type was invasive ductal carcinoma, NOS (90.7%). The proportion of each subtype was hormone receptor-positive and HER2-negative, 44.7%; hormone receptor-positive and HER2-positive, 3.9%; hormone receptor-negative and HER2-positive, 13.2%; and triple-negative, 38.2%. ER was positive in 40.8% of the cases, while PR was positive in 47.4%. More than half of the cases were poorly differentiated cancer (65.8%), followed by moderately differentiated (34.2%). Tumors presented with pT2 (60.5%), followed by pT3 (25.0%) and pT4 (7.9%).

Conclusion:

Breast cancer among Lao women is characterized by a large percentage of the triple-negative subtype that is less susceptible to hormonal treatments. The empirical treatment with tamoxifen should be reconsidered since it would be less effective to these patients. More importantly, basic pathology services should be the first requirement in Lao PDR in order to provide adequate care.

Improving early detection of breast cancer in sub-Saharan Africa: why mammography may not be the way forward

Background and methods

The prevention and control of breast cancer in sub-Saharan Africa (SSA) is an increasingly critical public health issue. Breast cancer is the most frequent female cancer in SSA and mortality rates from this disease are the highest globally. Breast cancer has traditionally been considered a disease of high-income countries, and programs for early detection have been developed and implemented in these settings. However, screening programs for breast cancer in SSA have been less effective than in high-income countries. This article reviews the literature on breast cancer in SSA, focusing on early detection practices. It then examines the case for and against mammography and other early detection approaches for breast cancer in SSA.

Results

Women with breast cancer in SSA are younger compared with high-income countries. Most women present with advanced disease and because treatment options are limited, have poor prognoses. Delay between symptom onset and healthcare seeking is common. Engagement with early detection practices such as mammography and breast examination is low and contributes to late stage at diagnosis.

Discussion

While early detection of breast cancer through screening has contributed to important reductions in mortality in many high-income countries, most countries in SSA have not been able to implement and sustain screening programs due to financial, logistical and sociocultural constraints. Mammography is widely used in high-income countries but has several limitations in SSA and is likely to have a higher harm-to-benefit ratio. Breast self-examination and clinical breast examination are alternative early detection methods which are more widely used by women in SSA compared with mammography, and are less resource intensive. An alternative approach to breast cancer screening programs for SSA is clinical downstaging, where the focus is on detecting breast cancer earlier in symptomatic women. Evidence demonstrates effectiveness of clinical downstaging among women presenting with late stage disease.

Conclusions

Approaches for early detection of breast cancer in SSA need to be context-specific. While screening programs with mammography have been effective in high-income countries, evidence suggests that other strategies might be equally important in reducing mortality from breast cancer, particularly in low-resource settings. There is a strong argument for further research into the feasability and acceptability of clinical downstaging for the control of breast cancer in SSA.

Electronic supplementary material

The online version of this article (10.1186/s12992-018-0446-6) contains supplementary material, which is available to authorized users.

Comparison of Receptor-Defined Breast Cancer Subtypes Between German and Sudanese Women: A Facility-Based Cohort Study

PURPOSE

The objective of this study was to compare tumor characteristics, biomarkers, and surrogate subtypes of breast cancer between Sudanese and German women.

METHODS

Tumor characteristics and immunohistochemistry markers (estrogen receptor [ER], progesterone receptor [PR], and human epidermal growth factor receptor 2 [HER2]) were collected from the routine assessment of consecutive patients with invasive breast cancer diagnosed from 2010 to 2015 (Gezira University Pathology Laboratory, Gezira, Sudan) and from 1999 to 2013 (Breast Centre, Martin-Luther-University, Halle, Germany).

RESULTS

A total of 2,492 patients (German [n = 1,932] and Sudanese [n = 560]) were included. Age at diagnosis ranged from 20 to 94 years. Sudanese women were, on average, 10 years younger than German women, with a mean (± standard deviation) age of 48.8 (13.5) and 58.6 (12.4) years, respectively. The Sudanese women had a higher grade, larger tumor, and more lymph node positivity compared with German women. ER-, PR-, and HER2-negative proportions were 55%, 61.8%, and 71.3%, respectively, for Sudanese women versus 22.7%, 32.3%, and 82.5%, respectively, for German women. The triple-negative subtype was more prevalent in Sudanese women (34.5%) than in German women (14.2%). The strongest factor associated with ER-negative disease was grade III (odds ratio, 19.6; 95% CI 11.6 to 33.4; P < .001). Sudanese patients were at higher risk for ER-negative breast cancer, with an odds ratio of 2.01 ( P = .001; adjusted for age, size, nodal status, histologic type, and grade). Stratified by grade, the influence of origin was observed in grade I and grade II tumors, but not in grade III tumors.

CONCLUSION

Sudanese women had more aggressive tumor characteristics and unfavorable prognostic biomarkers. After adjustment, Sudanese origin was still associated with hormone receptor-negative disease, especially in grade I and II tumors. These findings suggest differences in tumor biology among these ethnic groups.

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

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.

Breast Cancer in Low- and Middle-Income Countries: Why We Need Pathology Capability to Solve This Challenge

Breast cancer is the leading cause of cancer mortality among women in developing countries. Timely and accurate histopathological diagnosis of breast cancer is critical to delivering high-quality breast cancer care to patients in low- and middle-income countries (LMIC). The most important prognostic factors in breast cancer along with tumor size and nodal status are tumor grade, estrogen receptor status, as well as HER2 status in countries where specific targeted therapies are available. In addition, detailed and complete cancer registry data are needed to assess a country's disease burden and guide disease prioritization and allocation of resources for breast cancer treatment. Innovations in leapfrog technology and low-cost point-of-care tests for molecular evaluations are needed to provide accurate and timely pathology, with the ultimate goal of improving survival outcomes for patients with breast cancer in LMIC.

Immunohistochemistry defined subtypes of breast cancer in 678 Sudanese and Eritrean women; hospitals based case series

BACKGROUND

Breast cancer is the most common malignancy accounting for 25% of all cancers in females. In Africa, breast cancer prevalence and mortality are steadily increasing. Knowledge of hormone receptors and human epidermal growth factor receptor-2 (HER-2) expressions are vital for breast cancer management plans and decision making. There is wide regional variation in the proportion of these biomarkers, especially in African countries. Hormone receptors positivity in indigenous African and African American women is considered to be low and triple negative breast cancer is a dominant phenotype. There is paucity of data regarding hormone receptors (ER and PR) and HER2 expressions in North-eastern Africa (Eritrea and Sudan). The purpose of this study was to evaluate the expression of ER, PR and HER2 in Eritrean and Sudanese case series and correlate these biomarkers with the clinicopathological profile.

METHOD

Clinicopathologic data of patients were collected from clinical records. Immunohistochemistry biomarkers (ER, PR, and HER2) were assessed in consecutive female patients who had been diagnosed with invasive breast cancer from 2011 to 2015 in Gezira University Pathology Laboratory, the Sudan and National Health laboratory, Asmara, Eritrea.

RESULTS

There were 678 cases involved in this study. The mean age was 48.8 years with ±0.53 standard error of the mean. Two-thirds of the case were ≤50 years. Invasive ductal carcinoma, no special type was the most dominant histologic type (86%) in both study groups. The majority of cases (70%) had tumour stage pT2 and pT3 and about 50% had lymph node involvement. Less than 5% of the cases had well-differentiated tumours. The ER, PR and HER2 positive rates were 45%, 32%, and 29%, respectively. The proportion of luminal-A like, luminal-B like, HER2 enriched and TNBC were 37%, 13%, 16% and 34%, respectively. Fisher extract analysis showed age (p = .015), tumour size (p = .041), and histologic grade (p = .000) were significantly associated with intrinsic subtypes. Furthermore, Logistic regression analysis stratified by origin, age, tumour size, lymph-node metastasis and grade indicated that younger women age (≤50 years) and grade III tumours were more likely to be diagnosed with ER negative breast cancer.

CONCLUSION

Most of Sudanese and Eritrean women were diagnosed at younger age and with unfavourable prognostic clinicopathologic prognostic markers. TNBC is more frequent in this cohort study; patients with grade III tumours and young age are more likely to be hormone receptors negative. Therefore, routine determination of hormone receptors is warranted for appropriate targeted therapy.

Breast cancer in Angola, molecular subtypes: a first glance

Purpose

The aim of this study was to investigate the breast cancer (BC) molecular subtypes according to its surrogate immunohistochemistry (IHC) markers. We conducted a preliminary study, to correlate the clinical pathological profiles and molecular subtypes of breast cancer in Luanda, Angola.

Methods

From January 2011 to 30 December 2014, 140 consecutive cases of microscopically confirmed invasive breast carcinoma were classified regarding histology and IHC (ER, PR, HER2, and Ki-67). Surrogate molecular subtypes were classified according to ESMO recommendations.

Results

All patients were female; the median age was 47 years (24–84 years). Invasive carcinoma NST was the most common type (91.4%) and grade 2 was prevalent (70.7%). Most tumours were locally advanced (stage III – 65% and stage IV – 3.6%). In 140 studied cases, 74 (52.8%) malignancies were hormone receptor positive; 25.7% were luminal A like, 19.3% luminal B and HER2 negative like, 7.9% luminal B and HER2-positive like, 15.7% HER2 positive, and 31.4% were triple negative.

Conclusion

Women’s BC in Luanda-Angola is diagnosed at a young age and at an advanced stage. The two predominant molecular subtypes are HR positive and triple negative. The percentage of HER2-positive BC cases was high. Determining the molecular subtype using surrogate IHC markers has important treatment and prognostic implications for Angolan women with BC. There is an urgent need to study a prospective BC series in order to confirm the present results.

Tumor infiltrating leukocyte density is independent of tumor grade and molecular subtype in aggressive breast cancer of Western Kenya

Background

Tumors commonly are infiltrated by leukocytes, or tumor infiltrating leukocytes (TILs). It remains unclear, however, if the density and type of individual TILs has a direct or simply correlative role in promoting poor prognosis in breast cancer patients. Breast cancer in Kenyan women is aggressive with presentation at a young age, with advanced grade (grade III), large tumor size (>2.0 cm), and poor prognosis. We previously observed that the tumors were predominantly estrogen receptor positive (ER+) but also included both a high percentage of triple negative tumors and also increased immune cell infiltration within the tumors. We used breast tumor tissues from each patient to make tissue microarrays that were then stained for leukocyte and myeloid markers including CD4, CD8, CD20, CD25, CD68, and CD163 using immunohistochemical techniques. The immune cell infiltration into the cancer tissue included increased numbers of macrophages (CD68+), helper T cells (CD4+), and CD25+ lymphocytes compared to benign tissue.

Results

This study characterized the grade, molecular subtypes, and proliferation index of these tumors and determined if TIL density was enriched across any of these factors. We analyzed 49 malignant patient tissue samples for this study. The patient population had a mean age of 51.9 years. The tumors analyzed were heterogeneous by grade: grade I (6%), grade II (47%), and grade III (39%). Most patients presented with large tumors (>2.0 cm) (69%). We classified the tumors into molecular subtypes based on clinical marker expression. Based on this analysis, the molecular subtype distribution was heterogeneous with luminal B (41%), basal/triple negative (TN) (37%), luminal A (14%) and HER2 (8%) breast cancer subtypes. While the basal/TN subtype had a much higher proliferative index (Ki-67+) than did the other molecular subtypes, we did not see a significant correlation between TIL density and either subtype or tumor grade. Therefore, TIL density is independent of molecular subtype and grade.

Conclusion

This study identified a Kenyan patient cohort that develops large, high-grade tumors primarily of the luminal B and basal molecular subtypes. After analyzing the TILs within these tumors, we found that immune cell infiltration of these tumors correlated with increased proliferation but not grade or molecular subtype. Future research is required to determine if the aberrant recruitment of TILs to tumors contributes to cancer progression and response to cancer treatments.

Breast Cancer Molecular Subtypes Defined by ER/PR and HER2 Status: Association with Clinicopathologic Parameters in Ivorian Patients

BACKGROUND

Breast cancer is a heterogeneous disease that represents a major public health problem. The immunohistochemical determination of breast cancer subtypes with regard to estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor (HER2) status can contribute to improved selection of therapy and patientcare. The purpose of this study was to determine the prevalence of the molecular breast cancer subtypes and to assess their associations with classical clinicopathologic parameters for better therapeutic decisions in women with breast cancer in the Ivory Coast.

MATERIALS AND METHODS

Formalin- fixed and paraffin-embedded blocks of patients diagnosed with primary breast carcinoma were subjected to immunohistochemical assay for the assessment of ER/RP and HER2 expression. The one-way analysis of variance evaluated the difference between breast cancer subtypes and mean age of patients. The Chi-square Test was used to compare standard clinicopathologic prognostic parameters with tumor subtypes.

RESULTS

Among 302 patients, 57% were premenopausal and 43% were postmenopausal. The invasive ductal carcinoma not otherwise specified (IDC NOS) (82.8%) was the most frequent histological type, and the tumor grade 2 (56%) was predominant followed by grade 3 (20.9%). The proportion of positivity of ER, PR, and HER2 was 56%, 49%, and 15.6%, respectively. Half of patients of this study (51.6%) had luminal A breast tumor type followed by TN (32.1%). Other subtypes were luminal B (10.1% ) and non-luminal HER2+ (6.3%).

CONCLUSIONS

The findings of the present study are in line with the literature and should assist in management of breast cancer in our country.

First report on molecular breast cancer subtypes and their clinico-pathological characteristics in Eastern Morocco: series of 2260 cases

BACKGROUND

Breast cancer is the most frequent malignancy among women in Eastern Morocco. In this paper, we provide the first report on molecular breast cancer subtypes in this region. This is the largest population-based study on breast cancer among Moroccan women.

METHODS

We analyzed 2260 breast cancer cases diagnosed at the Hassan II Regional Oncology Center between October 2005 and December 2012. Clinico-pathological and therapeutic features were studied. Molecular subtypes were determined and their associations with the clinico-pathological characteristics of the tumors were examined.

RESULTS

The mean age at diagnosis was 48.7 years ±11.4. Invasive ductal carcinoma was the predominant histological type (77.1%), followed by lobular invasive carcinoma (15.3%). The mean size of breast tumors was 3.5 cm ± 1.96, and 84% of our patients are diagnosed with tumors of more than 2 cm. Histological grade II tumors were the most frequent (70.4%), followed by advanced histological grade (18%). Lymph node positive tumors were observed in 64.8% of cases and 29.3% of patients had distant metastasis. Most tumors were hormone receptor-positive (73%) and 28.6% were HER2 positive. 86.1% of patients with hormone receptor-positive breast cancer were given hormone therapy, while 68.9% of patients with HER2+ breast cancer received targeted therapy with Herceptin. Luminal A was the commonest molecular subtype, followed by Luminal B, Triple Negative and HER2. The highest prevalence of premenopausal patients was observed in Triple Negative subtype (72.2%), followed by HER2 (64.1%), Luminal B (62.2%), and Luminal A (55.1%). Luminal B subtype had a poorer prognosis than Luminal A. Compared with Triple Negative, HER2 subtype tend to spread more aggressively and is associated with poorer prognosis.

CONCLUSIONS

Unlike Western countries, breast cancer occurs at an earlier age and is diagnosed at a more advanced stage in Eastern Morocco. In this region, hormone receptor-positive tumors are predominant and so the majority of breast cancer patients should benefit from hormone therapy. HER2 subtype presents an aggressive tendency, suggesting the importance of anti-HER2 therapy. This study will contribute in developing appropriate screening and cancer management strategies in Eastern Morocco.

Correlation of Hormone Receptor and Human Epidermal Growth Factor Receptor-2/neu Expression in Breast Cancer with Various Clinicopathologic Factors

Background

A significant development in the breast carcinoma management is the correlation between the presence of hormone receptors in the tumor and response to hormonal therapy and chemotherapy. Human epidermal growth factor receptor-2/neu (Her-2/neu) overexpression also serves as a very useful parameter to predict response to herceptin.

Aim of Study

The study was conducted to correlate immunohistochemical expression of markers such as estrogen receptor (ER), progesterone receptor (PR), and Her-2/neu with various clinicopathologic parameters.

Materials and Methods

The study included 509 cases of breast carcinoma over a period of 5 years (from May 2009 to May 2014). Immunohistochemistry (IHC) for ER, PR, and her-2/neu was performed.

Results

ER positivity was observed in 42.8% (218/509) cases, PR positivity in 31.8% (194/509) cases whereas her-2 neu positivity was seen in 40.7% (203/509) cases. Triple marker (ER, PR, and Her-2/neu) negative cases were 23.6% (120/509) cases. ER and PR expression was found to have a statistically significant correlation with tumor grade. Statistically significant correlation was observed between tumor size and tumor grade and her-2/neu expression. Her-2/neu expression showed statistically significant association with tumor stage. As the tumor grade increased, the proportion of triple-negative cases went on increasing, which was statistically significant.

Conclusion

IHC has an increasingly important prognostic role in determination of factors that affect clinicopathologic features. Nevertheless, the results of this large series showed different patterns of findings with respect to clinicopathologic features.

Aggressive breast cancer in western Kenya has early onset, high proliferation, and immune cell infiltration

Background

Breast cancer incidence and mortality vary significantly among different nations and racial groups. African nations have the highest breast cancer mortality rates in the world, even though the incidence rates are below those of many nations. Differences in disease progression suggest that aggressive breast tumors may harbor a unique molecular signature to promote disease progression. However, few studies have investigated the pathology and clinical markers expressed in breast tissue from regional African patient populations.

Methods

We collected 68 malignant and 89 non-cancerous samples from Kenyan breast tissue. To characterize the tumors from these patients, we constructed tissue microarrays (TMAs) from these tissues. Sections from these TMAs were stained and analyzed using immunohistochemistry to detect clinical breast cancer markers, including estrogen receptor (ER), progesterone receptor (PR), human epidermal growth factor 2 receptor (HER2) status, Ki67, and immune cell markers.

Results

Thirty-three percent of the tumors were triple negative (ER-, PR-, HER2-), 59 % were ER+, and almost all tumors analyzed were HER2-. Seven percent of the breast cancer patients were male, and 30 % were <40 years old at diagnosis. Cancer tissue had increased immune cell infiltration with recruitment of CD163+ (M2 macrophage), CD25+ (regulatory T lymphocyte), and CD4+ (T helper) cells compared to non-cancer tissue.

Conclusions

We identified clinical biomarkers that may assist in identifying therapy strategies for breast cancer patients in western Kenya. Estrogen receptor status in particular should lead initial treatment strategies in these breast cancer patients. Increased CD25 expression suggests a need for additional treatment strategies designed to overcome immune suppression by CD25+ cells in order to promote the antitumor activity of CD8+ cytotoxic T cells.

Electronic supplementary material

The online version of this article (doi:10.1186/s12885-016-2204-6) contains supplementary material, which is available to authorized users.

Histological Features and Tissue Microarray Taxonomy of Nigerian Breast Cancer Reveal Predominance of the High-Grade Triple-Negative Phenotype

INTRODUCTION

Little is known about the biology, molecular profile and hence optimal treatment of African Nigerian breast cancer. The aim of this work, therefore, was to characterize the histology and molecular profile of Nigerian breast cancer.

METHODS

Breast carcinomas from women at 6 centres of similar tribal origin in Nigeria were reviewed and assembled into tissue microarrays (TMAs), and sections were stained for hormone receptors, i.e. estrogen receptor (ER)α, ERβ1, ERβ progesterone receptor (PR) and androgen receptor, cyclin D, HER2, Ki67 and cytokeratins (CKs), i.e. CK5/6 and CK14 (basal) and CK18 and 19 (luminal).

RESULTS

A total of 835 tumours were analysed. The mean age at diagnosis was 48.62 ± 12.41 years. The most common histological subtype was ductal NST (no-special-type) carcinoma (87.3%). Over 90% of the tumours were grade 2 or 3. The predominant molecular phenotype was the non-basal, triple-negative type (47.65%) followed by the HER2-positive group (19.6%). The percentage of ER-, PR- and HER2-positive tumours was 22.4, 18.9 and 18.8%, respectively.

CONCLUSION

Nigerian breast cancer predominantly has a high-grade, triple-negative profile. It occurs at a younger age and bears similarities at the molecular level to pre-menopausal breast cancer in white women, with remarkably lower levels of ERβ expression. The early presentation and histological and molecular phenotype may explain the poor prognosis, and tailoring treatment strategies to target this unique profile are required.

Copy Number Analysis of the DLX4 and ERBB2 Genes in South African Breast Cancer Patients

Breast cancer is one of the main causes of cancer death among South African women. Although several risk factors can be attributed to the observed high mortality rate, the biology of the tumors is not extensively investigated. Copy number gain of the DLX4 homeobox gene has been observed in breast cancer in association with poor prognosis and specific racial groups. Therefore, we aimed to assess the copy number and prognostic role of DLX4 in breast cancer from South African patients. Due to the co-location of ERBB2 and DLX4 in the 17q21 region, its copy number was also evaluated. Our results in the analysis of 66 cases demonstrated copy number gains of DLX4 and ERBB2 in 24.1 and 29.7% of the cases, respectively. Linear regression analysis showed no dependency between the copy number alterations in these genes. Although not significant, patients with DLX4 and ERBB2 gains presented a higher frequency of advanced-grade tumors. In addition, copy number alterations of these genes were not significantly differently observed in the 3 main racial groups of the Western Cape population: Colored, White, and Black. These findings indicate that gains of DLX4 and ERBB2 occur in South African breast cancer patients irrespectively of their race and factors known to influence prognosis.

A retrospective analysis of breast cancer subtype based on ER/PR and HER2 status in Ghanaian patients at the Korle Bu Teaching Hospital, Ghana

Background

Breast cancer is a heterogeneous disease composed of multiple subgroups with different molecular alterations, cellular composition, clinical behaviour, and response to treatment. This study evaluates the occurrence of the various subtypes and their clinical and pathological behaviour in the Ghanaian breast cancer population at the Korle Bu Teaching Hospital (KBTH).

Methods

Retrospective review of case notes of patients who had completed treatment for breast cancer at the KBTH within the last 5 years was conducted between April 2011 and March 2012. Subtypes were determined by immunohistochemistry classification based on expression of estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor-2 (HER-2).

Result

A total of 165 cases contributed to this study. The mean age at diagnosis was 52.5 ± 12.1 years. Tumour size ranged from 0.8 cm to 15 cm with a mean of 4.9 ± 2.8 cm and median of 4 cm. Tumour grade was Grade I 8.3 %, Grade II 60.8 % and Grade III 30.8 %. ER, PR and HER2/neu receptor positivity was 32.1, 25.6 and 25.5 % respectively. Almost half (49.4 %) of the study population had triple negative tumours. Luminal A, luminal B and non-luminal HER2 were 25.6, 12.2, and 12.8 % respectively. No statistically significant association was seen between subtype and tumour size, tumour grade, lymph node status and age at diagnosis.

Conclusion

Triple negative tumour is the most occurring subtype in the Ghanaian breast cancer population treated at the Korle Bu Teaching Hospital. Lack of association seen between subtypes and their clinical and pathological behaviour could be due to small sample size.

No difference in the prevalence of benign breast changes between women from Ghana and Norway: an autopsy study

Breast carcinoma develops gradually through multiple steps, some of which are recognizable as benign or premalignant histological changes. The age-standardized breast-cancer incidence rate is three times higher in Norway than in Ghana. A similar difference in the prevalence of benign and premalignant breast changes in the general populations would be expected if the difference in incidence rates were mainly due to cancer initiation factors, but not if it were caused by later stage promotion and progression factors. Breast tissue was taken by a standardized protocol from the autopsies of 44 Ghanaian and 26 Norwegian women between 15 and 60 years of age. Blind-labelled hematoxylin and eosin stained sections were examined independently by each of the three authors and the occurrence of histological changes in each section was recorded. The study revealed no significant difference between Norwegian and Ghanaian women in the prevalence of either proliferative or non-proliferative breast changes. The recorded incidence of breast cancer in Ghana may be under-estimated because of lower access to health services, lower patient awareness, and absence of population screening for breast cancer. Otherwise, the results support the conclusion that the lower incidence of breast cancer in Ghana than in Norway is mainly due to late-stage promotion and progression rather than initiation factors.

Clinical and histopathological factors associated with Ki-67 expression in breast cancer patients

The aim of the present study was to identify the optimal Ki-67 cut-off value in breast cancer (BC) patients, and investigate the association of Ki-67 expression levels with other prognostic factors. Firstly, a retrospective search was performed to identify patients with stage I–III BC (n=462). A range of Ki-67 index values were then assigned to five groups (<10, 10–14, 15–19, 20–24 and ≥25%). The correlation between the Ki-67 index and other prognostic factors [age, tumor type, histological and nuclear grade, tumor size, multifocality, an in situ component, lymphovascular invasion (LVI), estrogen and progesterone receptor (ER/PR) expression, human epidermal growth factor receptor (HER-2) status, axillary involvement and tumor stage] were investigated in each group. The median Ki-67 value was revealed to be 20% (range, 1–95%). A young age (≤40 years old), tumor type, size and grade, LVI, ER/PR negativity and HER-2 positivity were revealed to be associated with the Ki-67 level. Furthermore, Ki-67 was demonstrated to be negatively correlated with ER/PR expression (P<0.001), but positively correlated with tumor size (P<0.001). The multivariate analysis revealed that a Ki-67 value of ≥15% was associated with the largest number of poor prognostic factors (P=0.036). In addition, a Ki-67 value of ≥15% was identified to be statistically significant in association with certain luminal subtypes. The rate of disease-free survival was higher in patients with luminal A subtype BC (P=0.036). Following the correlation analysis for the Ki-67 index and the other prognostic factors, a Ki-67 value of ≥15% was revealed to be the optimal cut-off level for BC patients.

The prevalence of estrogen receptor-negative breast cancer in Ethiopia

Background

In contrast with breast cancers (BCs) in other parts of the world, most previous studies reported that the majority of BCs in sub-Saharan Africa are estrogen-receptor (ER) negative. However, a recent study using the US SEER database showed that the proportion of ER-negative BC is comparable between US-born blacks and West-African born blacks but substantially lower in East African-born blacks, with over 74% of patients Ethiopians or Eritreans. In this paper, we provide the first report on the proportion of ER-negative BC in Ethiopia, and the relation to progesterone-receptor (PgR) status.

Methods

We analysed 352 female patients with ER results available out of 1208 consecutive female BC patients treated at Addis Ababa-University Hospital, Ethiopia, from June 2005 through December 2010. The influences of age, stage, and histology on the probability of ER-negative tumours were assessed by a log-linear regression model.

Results

Of the 352 patients, only 35% were ER-negative. The proportion of ER-negative tumours decreased with advancing age at diagnosis and was not affected by histology or stage. For age, the proportion decreased by 6% for each additional 5 years (stage-adjusted prevalence ratio PR = 0.94, 95% CI: 0.89–1.00). About 31% were ER- and PgR-negative, and 69% were ER- and/or PgR-positive.

Conclusions

Contrary to most previous reports in other parts of sub-Saharan Africa, the majority of patients in Ethiopia are ER-positive rather than ER-negative. These findings are in line with low proportions of ER-negative BCs from East African immigrants within the SEER database, and they have clinical implications for management of BC patients in Ethiopia and other parts of sub-Saharan Africa where ER-status is not ascertained as part of routine management of the disease. Since the majority of patients showed ER-positive BC, Tamoxifen-therapy should be given to all patients even with unknown ER status.

Racial comparison of receptor-defined breast cancer in Southern African women: subtype prevalence and age-incidence analysis of nationwide cancer registry data

BACKGROUND

Receptor-defined breast cancer proportions vary across Africa. They have important implications for survival prospects and research priorities.

METHODS

We studied estrogen receptor (ER), progesterone receptor (PR), and HER2 receptor statuses in two multiracial Southern African countries with routine diagnostic immunohistochemistry. A total of 12,361 women with histologically confirmed breast cancer diagnosed at age ≥20 years during (i) 2009-2011 from South Africa's national cancer registry (public sector) and (ii) 2011-2013 from Namibia's only cancer hospital were included. Crude, age, and age + laboratory-adjusted ORs of receptor status were analyzed using logistic regression, and age-incidence curves were analyzed using Poisson regression.

RESULTS

A total of 10,047 (81%) women had known ER status. Ranking of subtypes was consistent across races: ER(+)/PR(+)HER2(-) was most common (race-specific percentage range, 54.6%-64.8%), followed by triple-negative (17.4%-21.9%), ER(+)/PR(+)HER2(+) (9.6%-13.9%), and ER(-)PR(-)HER2(+) (7.8%-10.9%). Percentages in black versus white women were 33.8% [95% confidence (CI), 32.5-35.0] versus 26.0% (24.0-27.9) ER(-); 20.9% (19.7-22.1) versus 17.5% (15.4-19.6) triple-negative; and 10.7% (9.8-11.6) versus 7.8% (6.3-9.3) ER(-)PR(-)HER2(+). Indian/Asian and mixed-ancestry women had intermediate values. Age-incidence curves had similar shapes across races: rates increased by 12.7% per year (12.2-13.1) across ER subtypes under the age of 50 years, and thereafter slowed for ER(+) (1.95%) and plateaued for ER(-) disease (-0.1%).

CONCLUSIONS

ER(+) breast cancer dominates in all Southern African races, but black women have a modest excess of aggressive subtypes.

IMPACT

On the basis of the predominant receptor-defined breast tumors in Southern Africa, improving survival for the growing breast cancer burden should be achievable through earlier diagnosis and appropriate treatment.

Stage at breast cancer diagnosis and distance from diagnostic hospital in a periurban setting: a South African public hospital case series of over 1,000 women

Advanced stage at diagnosis contributes to low breast cancer survival rates in sub-Saharan Africa. Living far from health services is known to delay presentation, but the effect of residential distance to hospital, the radius at which this effect sets in and the women most affected have not been quantified. In a periurban South African setting, we examined the effect of a geographic information system (GIS)-measured straight-line distance, from a patient's residence to diagnostic hospital, on stage at diagnosis in 1,071 public-sector breast cancer patients diagnosed during 2006-2012. Generalized linear models were used to estimate risk ratios for late stage (stage III/IV vs. stage I/II) associated with distance, adjusting for year of diagnosis, age, race and socioeconomic indicators. Mean age of patients was 55 years, 90% were black African and diagnoses were at stages I (5%), II (41%), III (46%) and IV (8%). Sixty-two percent of patients with distances >20 km (n = 338) had a late stage at diagnosis compared to 50% with distances <20 km (n = 713, p = 0.02). Risk of late stage at diagnosis was 1.25-fold higher (95% CI: 1.09, 1.42) per 30 km. Effects were pronounced in an underrepresented group of patients over age 70. This positive stage-distance association held to 40 km, and plateaued or slightly reversed in patients (9%) living beyond this distance. Studies of woman and the societal and healthcare-level influences on these delays and on the late stage at diagnosis distribution are needed to inform interventions to improve diagnostic stage and breast cancer survival in this and similar settings.

Breast cancer receptor status and stage at diagnosis in over 1,200 consecutive public hospital patients in Soweto, South Africa: a case series

Introduction

Estimates of the proportion of estrogen receptor negative (ERN) and triple-negative (TRN) breast cancer from sub-Saharan Africa are variable and include high values. Large studies of receptor status conducted on non-archival tissue are lacking from this region.

Methods

We identified 1218 consecutive women (91% black) diagnosed with invasive breast cancer from 2006–2012 at a public hospital in Soweto, South Africa. Immunohistochemistry based ER, progesterone receptor (PR) and human epidermal factor 2 (HER2) receptors were assessed at diagnosis on pre-treatment biopsy specimens. Mutually adjusted associations of receptor status with stage, age, and race were examined using risk ratios (RRs). ER status was compared with age-stratified US Surveillance Epidemiology and End Results program (SEER) data.

Results

35% (95% confidence interval (CI): 32–38) of tumors were ERN, 47% (45–52) PRN, 26% (23–29) HER2P and 21% (18–23) TRN. Later stage tumors were more likely to be ERN and PRN (RRs 1.9 (1.1-2.9) and 2.0 (1.3-3.1) for stage III vs. I) but were not strongly associated with HER2 status. Age was not strongly associated with ER or PR status, but older women were less likely to have HER2P tumors (RR, 0.95 (0.92-0.99) per 5 years). During the study, stage III + IV tumors decreased from 66% to 46%. In black women the percentage of ERN (37% (34–40)) and PRN tumors (48% (45–52)) was higher than in non-black patients (22% (14–31) and 34% (25–44), respectively, P = 0.004 and P = 0.02), which remained after age and stage adjustment. Age-specific ERN proportions in black South African women were similar to those of US black women, especially for women diagnosed over age 50.

Conclusion

Although a greater proportion of black than non-black South African women had ER-negative or TRN breast cancer, in all racial groups in this study breast cancer was predominantly ER-positive and was being diagnosed at earlier stages over time. These observations provide initial indications that late-stage aggressive breast cancers may not be an inherent feature of the breast cancer burden across Africa.

Challenges in the detection, prevention, and treatment of HIV-associated malignancies in low- and middle-income countries in Africa

Cancers associated with immunosuppression and infections have long been recognized as a major complication of HIV/AIDS. More recently, persons living with HIV are increasingly diagnosed with a wider spectrum of HIV-associated malignancies (HIVAM) as they live longer on combination antiretroviral therapy. This has spurred research to characterize the epidemiology and determine the optimal management of HIVAM with a focus on low-and middle-income countries (LMICs). Given background coinfections, environmental exposures, host genetic profiles, antiretroviral therapy usage, and varying capacities for early diagnosis and treatment, one can expect the biology of cancers in HIV-infected persons in LMICs to have a significant impact on chronic HIV care, as is now the case in high-income countries. Thus, new strategies must be developed to effectively prevent, diagnose, and treat HIVAM in LMICs; provide physical/clinical infrastructures; train the cancer and HIV workforce; and expand research capacity-particularly given the challenges posed by the limitations on available transportation and financial resources and the population's general rural concentration. Opportunities exist to extend resources supported by the President's Emergency Plan for AIDS Relief and the Global Fund to Fight AIDS, Tuberculosis, and Malaria to improve the health-care infrastructure and train the personnel required to prevent and manage cancers in persons living with HIV. These HIV chronic care infrastructures could also serve cancer patients regardless of their HIV status, facilitating long-term care and treatment for persons who do not live near cancer centers, so that they receive the same degree of care as those receiving chronic HIV care today.

Receptor-defined subtypes of breast cancer in indigenous populations in Africa: a systematic review and meta-analysis

BACKGROUND

Breast cancer is the most common female cancer in Africa. Receptor-defined subtypes are a major determinant of treatment options and disease outcomes but there is considerable uncertainty regarding the frequency of poor prognosis estrogen receptor (ER) negative subtypes in Africa. We systematically reviewed publications reporting on the frequency of breast cancer receptor-defined subtypes in indigenous populations in Africa.

METHODS AND FINDINGS

Medline, Embase, and Global Health were searched for studies published between 1st January 1980 and 15th April 2014. Reported proportions of ER positive (ER+), progesterone receptor positive (PR+), and human epidermal growth factor receptor-2 positive (HER2+) disease were extracted and 95% CI calculated. Random effects meta-analyses were used to pool estimates. Fifty-four studies from North Africa (n=12,284 women with breast cancer) and 26 from sub-Saharan Africa (n=4,737) were eligible. There was marked between-study heterogeneity in the ER+ estimates in both regions (I2>90%), with the majority reporting proportions between 0.40 and 0.80 in North Africa and between 0.20 and 0.70 in sub-Saharan Africa. Similarly, large between-study heterogeneity was observed for PR+ and HER2+ estimates (I2>80%, in all instances). Meta-regression analyses showed that the proportion of ER+ disease was 10% (4%-17%) lower for studies based on archived tumor blocks rather than prospectively collected specimens, and 9% (2%-17%) lower for those with ≥ 40% versus those with <40% grade 3 tumors. For prospectively collected samples, the pooled proportions for ER+ and triple negative tumors were 0.59 (0.56-0.62) and 0.21 (0.17-0.25), respectively, regardless of region. Limitations of the study include the lack of standardized procedures across the various studies; the low methodological quality of many studies in terms of the representativeness of their case series and the quality of the procedures for collection, fixation, and receptor testing; and the possibility that women with breast cancer may have contributed to more than one study.

CONCLUSIONS

The published data from the more appropriate prospectively measured specimens are consistent with the majority of breast cancers in Africa being ER+. As no single subtype dominates in the continent availability of receptor testing should be a priority, especially for young women with early stage disease where appropriate receptor-specific treatment modalities offer the greatest potential for reducing years of life lost. Please see later in the article for the Editors' Summary.

Is breast cancer from Sub Saharan Africa truly receptor poor? Prevalence of ER/PR/HER2 in breast cancer from Kenya

OBJECTIVES

Studies on ER/PR/HER2 in breast cancer from Sub Saharan Africa (SSA) are fraught with inconsistencies in the prevalence of hormone receptor status. In Kenya, ER/PR/HER2 for breast cancers is not part of routine assessment and available in only three to four centers across the country. Variability in methodology and interpretation makes comparison between data difficult. Our aim was to accurately determine the prevalence of ER/PR/HER2 using standardized techniques and double reporting. Prognostic tumor parameters were also correlated with clinical features and receptor status.

MATERIALS AND METHODS

Consecutive invasive breast cancers (IBC) accrued between September 2011 and December 2012 were analyzed at Aga Khan University Hospital, Nairobi (AKUHN). Tumor blocks were stained for ER/PR/HER2 on an automated platform. Double reporting of ER/PR/HER2 was done using the Allred system and the ASCO/CAP guidelines respectively.

RESULTS

A total of 301 cases of IBC were analyzed for pathology and ER/PR/HER2. The age range of patients was 19-94 years with a median of 47.5 years. Invasive ductal carcinoma (NOS) was the most common histologic type (84.2%). ER positivity was seen in 72.8%, PR in 64.8% and HER2 in 17.6% of all cases. Triple negative breast cancers (TNBC) constituted 20.2% of the cases. There was a significant association between receptor status and histologic grade (p < 0.001) and statistically significant trend of increasing pathological stage of tumor (pT) associated with TNBC (p = 0.020).

CONCLUSIONS

We present a definitive prospective analysis of ER/PR/HER2 from a single center and demonstrate that prevalence of receptor status from SSA is comparable with that in the West.

Cancer in Africa 2012

BACKGROUND

Noncommunicable diseases, and especially cancers, are recognized as an increasing problem for low and middle income countries. Effective control programs require adequate information on the size, nature, and evolution of the health problem that they pose.

METHODS

We present estimates of the incidence and mortality of cancer in Africa in 2012, derived from "GLOBOCAN 2012," published by the International Agency for Research on Cancer.

RESULTS

There were 847,000 new cancer cases (6% of the world total) and 591,000 deaths (7.2% of the world total) in the 54 countries of Africa in 2012, with about three quarters in the 47 countries of Sub-Saharan Africa. While the cancer profiles often differ markedly between regions, the most common cancers in men were prostate (16.4% of new cancers), liver (10.7%), and Kaposi sarcoma (6.7%); in women, by far the most important are cancers of the breast (27.6% of all cancers) and cervix uteri (20.4%).

CONCLUSIONS

There are still deficiencies in surveillance systems, particularly in Sub-Saharan Africa and, specifically, of their most vital component, population-based cancer registries. With the number of annual cancer cases and deaths likely to increase by at least 70% by 2030, there is a pressing need for a coordinated approach to improving the extent and quality of services for cancer control in Africa, and better surveillance systems with which they can be planned and monitored.

IMPACT

The results are the best data currently available and provide a reasonable appraisal of the cancer situation in Africa.

Frequency of 5382insC mutation of BRCA1 gene among breast cancer patients: an experience from Eastern India

The incidence of breast cancer in India is on the rise and is rapidly becoming the number one cancer in females pushing the cervical cancer to the second position. The mutations in two breast cancer susceptibility genes, BRCA1 and BRCA2, are frequently associated with familial breast cancer. The main objective of the study was to determine the frequency of the mutation 5382insC in BRCA1 of eastern Indian breast cancer patients and also study the hormonal receptor status and histopathology of the patients. Altogether 92 patients affected with breast cancer were included in this study. ARMS-PCR based amplification was used to detect the presence of mutation. The mutations were considered only after pedigree analysis. Out of 92 patients (age range: 20-77 years) with family history (57 individuals) and without family history (35 individuals) were screened. Fifty controls have been systematically investigated. Seven patients and two family members were found to be carriers of 5382insC mutation in BRCA1 gene. We have found 42.64 % ER(-)/PR(-) cancer and 20.58 % triple negative cancer. Invasive ductal carcinoma is the most common histology among the investigated individuals. The presented data confirm a noticeable contribution of BRCA1 5382insC mutation in BC development in Eastern India, which may justify an extended BRCA1 5382insC testing within this patient population. We found HER-2/neu negativity and BRCA1 positivity associated with familial breast cancer. From the hospital's patient history, it was revealed that the age of menarche plays an important role in development of breast cancer.

Radiation therapy: a major factor in the five-year survival analysis of women with breast cancer in Lagos, Nigeria

PURPOSE

This retrospective study was carried out to examine five-year survival from breast cancer cases diagnosed between 2005 and May 2008 in Nigerian women.

MATERIAL AND METHODS

Two hundred and twenty-four patients were entered into the study. Five-year survival was evaluated using proportional hazard model proposed by Cox to assess variables such as age of diagnosis, menopausal status, and stage of the disease in the two treatment groups: surgery/chemotherapy or surgery/chemotherapy/radiotherapy.

RESULTS

Findings revealed that the different staging of disease and treatment are independent predictors of disease outcome whereas age of diagnosis and menopausal status although associated with low hazards, are not significant. TNM Stage I (Hazard Ratio=0.153, 95% CI 0.45-0.51, P=0.003), II (Hazard Ratio=0.245, 95% CI 0.12-0.46, P=0.0001), and III (Hazard Ratio=0.449, 95% CI 0.31-0.46, P=0.0001) showed significantly greater survival rates compared to TNM Stage IV for patients receiving surgery/chemotherapy. Similarly, for patients receiving surgery/chemotherapy/radiotherapy TNM Stage II (Hazard Ratio=0.110, 95% CI 0.02-0.46, P=0.003) and III (Hazard Ratio=0.238, 95% CI 0.07-0.73, P=0.012) also showed significantly greater survival rates compared to TNM Stage IV. Treatment had a significant impact on survival independent of stage, age, and menopausal status. Patients receiving surgery/chemotherapy/radiotherapy had a significant increase in survival outcome for TNM Stage (II, P=0.045; III, P=0.0001); age groups (40-49, P=0.021; 50-59, P=0.016; 60-69, P=0.017; >70, P=0.025); and menopausal status (premenopausal, P=0.049; postmenopausal, P=0.0001) compared to those receiving surgery/chemotherapy.

CONCLUSION

The five-year breast cancer survival rate in Lagos, Nigeria 24.1% (54/224) is relatively poor compared to most countries in the world and needs to be improved. Poor survival rates are mainly attributed to late presentation and poor follow-up, hence early detection through breast cancer awareness programs, appropriate logistics and better management of patients through guidelines for the treatment of breast need to be implemented to improve survival.