Mosquito control exposures and breast cancer risk: analysis of 1071 cases and 2096 controls from the Ghana Breast Health Study

Epidemiologic data on insecticide exposures and breast cancer risk are inconclusive and mostly from high-income countries. Using data from 1071 invasive pathologically confirmed breast cancer cases and 2096 controls from the Ghana Breast Health Study conducted from 2013 to 2015, we investigated associations with mosquito control products to reduce the spread of mosquito-borne diseases, such as malaria. These mosquito control products were insecticide-treated nets, mosquito coils, repellent room sprays, and skin creams for personal protection against mosquitos. Multivariable and polytomous logistic regression models were used to estimate odds ratios (ORadj) and 95% confidence intervals (CI) with breast cancer risk-adjusted for potential confounders and known risk factors. Among controls, the reported use of mosquito control products were mosquito coils (65%), followed by insecticide-treated nets (56%), repellent room sprays (53%), and repellent skin creams (15%). Compared to a referent group of participants unexposed to mosquito control products, there was no significant association between breast cancer risk and mosquito coils. There was an association in breast cancer risk with reported use of insecticide-treated nets; however, that association was weak and not statistically significant. Participants who reported using repellent sprays were at elevated risks compared to women who did not use any mosquito control products, even after adjustment for all other mosquito control products (OR = 1.42, 95% CI=1.15-1.75). We had limited power to detect an association with repellent skin creams. Although only a few participants reported using repellent room sprays weekly/daily or < month-monthly, no trends were evident with increased frequency of use of repellent sprays, and there was no statistical evidence of heterogeneity by estrogen receptor (ER) status (p-het > 0.25). Our analysis was limited when determining if an association existed with repellent skin creams; therefore, we cannot conclude an association. We found limited evidence of risk associations with widely used mosquito coils and insecticide-treated nets, which are reassuring given their importance for malaria prevention. Our findings regarding specific breast cancer risk associations, specifically those observed between repellent sprays, require further study.

A gist on an obscure neoplasm in Ghana: gastrointestinal stromal tumours

BACKGROUND

Gastrointestinal Stromal Tumour is a rare but potentially curable tumour of the gastrointestinal tract accounting for up to 1% of all gastrointestinal tumours. The discovery of Imatinib mesylate, a novel tyrosine kinase inhibitor has improved the chances even for unresectable, recurrent, or metastatic diseases.

METHODS

This study sought to document the clinical and pathological characteristics of GISTs from two tertiary hospitals in Ghana that have undergone immunohistochemistry confirmation between 2014 and 2021.

RESULTS

The median age of the subjects was 50 years with most of them (28.0%) being above 61 years. There were more females than males (64.0% vs. 36.0%). Abdominal mass and abdominal pain made up the majority of the clinical presentations. The majority of the subjects had partial gastrectomy (32.0%) which was followed by wedge resection (28.0%). Appendectomy and sleeve gastrectomy were the least performed procedures (8% each). Four of the 25 patients (16.0%) had resections of involved contiguous organs done with splenectomy being the most common procedure. The majority of GISTs were found in the stomach (68.0%) followed by the appendix (12.0%) and small bowel (12.0%). Gastrointestinal bleeding (55.8%) and abdominal pain (38.5%) were the most reported symptoms. Free resection margins were observed in 84.0% of the subjects and only 3/25 (12.0%) experienced tumour recurrence.

CONCLUSION

GIST is a potentially curable tumour that once was obscure but currently gaining popularity. Surgical resection offers the hope of a cure for localized disease while targeted therapies is a viable option for recurrent, metastatic, or unresectable tumours.

Associations of Circulating Estrogens and Estrogen Metabolites with Fecal and Oral Microbiome in Postmenopausal Women in the Ghana Breast Health Study

The human fecal and oral microbiome may play a role in the etiology of breast cancer through modulation of endogenous estrogen metabolism. This study aimed to investigate associations of circulating estrogens and estrogen metabolites with the fecal and oral microbiome in postmenopausal African women. A total of 117 women with fecal (N = 110) and oral (N = 114) microbiome data measured by 16S rRNA gene sequencing, and estrogens and estrogen metabolites data measured by liquid chromatography tandem mass spectrometry were included. The outcomes were measures of the microbiome and the independent variables were the estrogens and estrogen metabolites. Estrogens and estrogen metabolites were associated with the fecal microbial Shannon index (global P < 0.01). In particular, higher levels of estrone (β = 0.36, P = 0.03), 2-hydroxyestradiol (β = 0.30, P = 0.02), 4-methoxyestrone (β = 0.51, P = 0.01), and estriol (β = 0.36, P = 0.04) were associated with higher levels of the Shannon index, while 16alpha-hydroxyestrone (β = -0.57, P < 0.01) was inversely associated with the Shannon index as indicated by linear regression. Conjugated 2-methoxyestrone was associated with oral microbial unweighted UniFrac as indicated by MiRKAT (P < 0.01) and PERMANOVA, where conjugated 2-methoxyestrone explained 2.67% of the oral microbial variability, but no other estrogens or estrogen metabolites were associated with any other beta diversity measures. The presence and abundance of multiple fecal and oral genera, such as fecal genera from families Lachnospiraceae and Ruminococcaceae, were associated with several estrogens and estrogen metabolites as indicated by zero-inflated negative binomial regression. Overall, we found several associations of specific estrogens and estrogen metabolites and the fecal and oral microbiome. IMPORTANCE Several epidemiologic studies have found associations of urinary estrogens and estrogen metabolites with the fecal microbiome. However, urinary estrogen concentrations are not strongly correlated with serum estrogens, a known risk factor for breast cancer. To better understand whether the human fecal and oral microbiome were associated with breast cancer risk via the regulation of estrogen metabolism, we conducted this study to investigate the associations of circulating estrogens and estrogen metabolites with the fecal and oral microbiome in postmenopausal African women. We found several associations of parent estrogens and several estrogen metabolites with the microbial communities, and multiple individual associations of estrogens and estrogen metabolites with the presence and abundance of multiple fecal and oral genera, such as fecal genera from families Lachnospiraceae and Ruminococcaceae, which have estrogen metabolizing properties. Future large, longitudinal studies to investigate the dynamic changes of the fecal and oral microbiome and estrogen relationship are needed.

Associations of breast cancer etiologic factors with stromal microenvironment of primary invasive breast cancers in the Ghana Breast Health Study

Background

Emerging data suggest that beyond the neoplastic parenchyma, the stromal microenvironment (SME) impacts tumor biology, including aggressiveness, metastatic potential, and response to treatment. However, the epidemiological determinants of SME biology remain poorly understood, more so among women of African ancestry who are disproportionately affected by aggressive breast cancer phenotypes.

Methods

Within the Ghana Breast Health Study, a population-based case-control study in Ghana, we applied high-accuracy machine-learning algorithms to characterize biologically-relevant SME phenotypes, including tumor-stroma ratio (TSR (%); a metric of connective tissue stroma to tumor ratio) and tumor-associated stromal cellular density (Ta-SCD (%); a tissue biomarker that is reminiscent of chronic inflammation and wound repair response in breast cancer), on digitized H&E-stained sections from 792 breast cancer patients aged 17-84 years. Kruskal-Wallis tests and multivariable linear regression models were used to test associations between established breast cancer risk factors, tumor characteristics, and SME phenotypes.

Results

Decreasing TSR and increasing Ta-SCD were strongly associated with aggressive, mostly high grade tumors (p-value < 0.001). Several etiologic factors were associated with Ta-SCD, but not TSR. Compared with nulliparous women [mean (standard deviation) = 28.9% (7.1%)], parous women [mean (standard deviation) = 31.3% (7.6%)] had statistically significantly higher levels of Ta-SCD (p-value = 0.01). Similarly, women with a positive family history of breast cancer [FHBC; mean (standard deviation) = 33.0% (7.5%)] had higher levels of Ta-SCD than those with no FHBC [mean (standard deviation) = 30.9% (7.6%); p-value = 0.01]. Conversely, increasing body size was associated with decreasing Ta-SCD [mean (standard deviation) = 32.0% (7.4%), 31.3% (7.3%), and 29.0% (8.0%) for slight, moderate, and large body sizes, respectively, p-value = 0.005]. These associations persisted and remained statistically significantly associated with Ta-SCD in mutually-adjusted multivariable linear regression models (p-value < 0.05). With the exception of body size, which was differentially associated with Ta-SCD by grade levels (p-heterogeneity = 0.04), associations between risk factors and Ta-SCD were not modified by tumor characteristics.

Conclusions

Our findings raise the possibility that epidemiological factors may act via the SME to impact both risk and biology of breast cancers in this population, underscoring the need for more population-based research into the role of SME in multi-state breast carcinogenesis.

Abstract 2247: Evaluation of multidrug resistant genes among breast cancer patients in Ghana

Background: Breast cancer (BC) is a leading cause of cancer death in Ghana and around the world. Ghanaian women are diagnosed at younger ages with the more aggressive Triple Negative BC (TNBC) subtype where West African ancestry is associated with advanced BC diagnosis and higher mortality rates compared to age-matched women of European ancestry. Genomic comparisons of BC tumors from women of African and European ancestry show differences in frequencies of single nucleotide polymorphisms (SNP) and copy number variations. These differences may contribute to disparities in disease and treatment outcomes observed in women of African ancestry. Chemotherapy plays a major role in treatment of recurrent and metastatic BC. Long-term BC survival remains poor especially in Africa due to multidrug resistance (MDR). MDR has been associated with binding cassette (ABC) protein transporters. ABCB1, ABCC1 and ABCG2 are ABC transporter genes that code for proteins involved in drug efflux. We hypothesize that SNPs in ABC transporter genes may alter their physiological protective role and increase risk of MDR, treatment failure and death among BC patients. Preliminary dataWe explored gene expression profiles of ABCB1, ABCC1 and ABCG2 in an African ancestry-enriched subset of women with TNBC (ICSBCS cohort: Ghanaian n = 6, African American (AA) n = 9, Ethiopian n = 11). Preliminary data showed significantly higher expression of ABCC1 among Ghanaian and AA patients compared to Ethiopians, and a significant positive correlation with African ancestry. ABCB1 and ABCG2 showed lower expression in all three groups (ns).To study the relationship between ABC transporter gene SNPs and MDR, we have collected data over a 3-year period (2019-2021) from the Oncology Department of the Komfo Anokye Teaching Hospital in Ghana. The overall prevalence of BC recurrence was 3.4% (CI = 2.5 - 4.7%), and prevalence of metastatic BC was 47.6% (CI = 44.6 - 50.6%).

Methodology: SNPs in ABC transporter genes will be obtained from 150 consented female BC patients who have undergone chemotherapy. We will compare genotype frequencies among patients with disease recurrence and/or metastasis (n = 100) to those with no disease recurrence or metastasis (n = 50). Single-plex genotyping of the ABC gene SNPs will be completed using a real-time PCR allelic discrimination assay.

Conclusion: ABCC1 has been established to be associated with African ancestry. Determining the association of ABC gene SNPs and MDR among Ghanaian BC patients will provide further information on allelic variants and their effects on BC treatment outcomes.

Citation Format: Gloria Agyekum Boaitey, Rachel Martini, Melissa B. Davis, Lisa Newman, Brian Stonaker, Linda Ahenkorah Fondjo, Christian Obirikorang, Ernest Osei Bonsu, Ernest Adjei, Ishmael Kyei, Mavis Bobie Ansah, Mahteme Bekele, Timothy Chu, Nicolas Robine. Evaluation of multidrug resistant genes among breast cancer patients in Ghana [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 2247.

Abstract NG03: Multiomics in disparities research: Identifying African ancestry-specific mechanisms in the triple negative breast cancer tumor microenvironment

Triple negative breast cancer (TNBC) represents the most aggressive subtype of breast cancer (BC),often diagnosed as early-onset and late-stage disease with worse prognosis due to lack of targeted therapeutic options. In the US, approximately 10% of BC diagnoses annually are TNBC, however, frequency of TNBC diagnoses are significantly higher among African American (AA) women, driving a 40% higher mortality rate among AA women compared to White/European American (EA) women. Work from our International Center for the Study of Breast Cancer Subtypes (ICSBCS) cohort has linked west African ancestry to frequency of TNBC diagnoses, where we reported increased TNBC disease among women of west African ancestry (AA and Ghanaian) compared EA or east African (Ethiopian) women. Quantification of west African ancestry across the ICSBCS cohort has revealed significantly higher percentage of west African ancestry among TNBC patients, and this significant result remained when only considering AA women with TNBC. We hypothesize that African ancestry-specific factors drive differences in TNBC tumor etiology, and in combination with external factors yield a unique TNBC tumor microenvironment (TME). Approaching this work with a genetic ancestry (versus self-reported race) focus allows us the opportunity to define these unique factors that will ultimately translate into targeted therapeutic opportunities for this underserved population. To address this persisting disparity, we have leveraged multiomics approaches to: (1) identify unique African ancestry-specific gene expression profiles and enrichments using transcriptomic approaches, and (2) determine mutational profiles and signatures enriched among women of African ancestry with TNBC with whole genome sequencing (WGS).

Utilizing a TNBC transcriptomics cohort enriched with women of African ancestry (n = 26), including AA, Ghanaian and Ethiopian TNBC patients, we have identified an African ancestry-associated gene signature comprised of 613 genes. After quantifying genetic ancestry across our patient cohort, we performed gene linear regression analyses to identify this gene signature. We also performed self-reported race (SRR) comparative analyses for differences in gene expression across population groups, and report that African ancestry associated gene are largely distinct from genes associated with SRR. Our African ancestry-associated gene signature revealed significant enrichment in immune cell trafficking pathways, where predicted activation of immune cell migration was observed among women with higher proportion of African ancestry. Deconvolution of the bulk RNAseq data revealed increases in tumor associated leukocytes proportions among AA and Ghanaian women, specifically B- and T- cell populations. Two separate validation cohorts looking at immunohistochemistry and multiplexed geospatial analysis also showed significant increases in T-cell infiltration into TNBC tumors of African ancestry women. Leveraging sub-continental ancestry estimations across the cohort, we additionally identified over 2000 genes associated with 5 African sub-continental reference populations, where significant enrichment in terms related to immune response was also observed. We hypothesize that these African ancestry-associated genes (1) will show enrichment with local ancestry estimates at the gene loci, and (2) that ancestral informative markers (AIMs) or population-private single nucleotide polymorphisms (SNPs) are expression quantitative trait loci (eQTLs) driving the observed African ancestry-specific gene expression observed. Workflow development is underway to apply local ancestry estimation methods to RNAseq data, to determine these associations in a loci-specific manner.

WGS analysis was also completed on a cohort of patients with TNBC (n = 51) and hormone receptor positive (HR+) BC (n =23). Both cohorts are primarily comprised of AA patients and include Ethiopian patients with HR+ BC (n = 4) and TNBC (n = 3), and Ghanaian patients with TNBC (n = 3). Analysis of top mutated genes revealed significantly high frequency of TP53 mutations in TNBC (82%) compared to HR+ cases (35%) (p = 0.0001), with primarily missense and nonsense mutations in the P53 DNA-binding domain. All TNBC African cases harbored TP53 mutation, where only 1 Ethiopian HR+ case had a TP53 missense mutation. We compared COSMIC mutational signatures between TP53 mutation carriers and non-carriers and report a significant increase in proportion of Signature 3 (p = 0.0298), associated with double-strand break repair, and Signature 8 (p = 0.0026), which is associated with BC but has an unknown etiology. Of note, Signature 3 is often associated with germline BRCA1/2 mutations, and work is underway to determine BRCA1/2 status across our cohort. We have also reported the rs2363956 germline variant of the ANKLE1 gene as a potential TNBC protective allele among AA women, where ANKLE1 is reported to play a role in DNA repair pathways. We observe a higher fraction of Signature 3 across among the minor allele of ANKLE1 rs2363956 GG genotype, and a similar, lower fraction of Signature 3 among heterozygotes (GT) and major allele (TT) genotypes. DNAH5 and DNAH9 missense mutations were also detected among TNBC cases (16% and 14%, respectively), and not among HR+ cases (0%) (p = 0.05, p = 0.09, respectively). Mutations in DNA5 have been associated with chemosensitivity in ovarian cancer patients, and mutations in both DNAH5 and DNAH9 genes have been associated with chemosensitivity among patients with gastric cancer. GATA3 mutations were found exclusively among HR+ cases (26%, p = 0.0005), and PIK3CA mutations were also found at a significantly higher frequency among HR+ cases (30%) compared to TNBC cases (8%) (p = 0.03).

Leveraging the diversity of our robust ICSBCS cohort, we have begun to define ancestry-associated phenotypes that are present in the TNBC TME of women with African ancestry. Our transcriptomic analyses have highlighted that ancestry-specific gene signatures are distinct from SRR-associated signatures, and we are currently working to define specific drivers of these ancestry-associated genes. We also highlight an increased immune response associated with higher fractions of African ancestry, that may provide opportunities to adapt current therapeutic options, such as immunotherapy, to this patient population. Our WGS work also highlights differences in mutational processes and mutation signatures among African ancestry women with TNBC and nonTNBC disease. We report an increased burden of TP53 mutations is present among TNBC patients and is highly correlated to increased Signature 3, which is associated with BRCAness and DNA repair deficiency. Work is currently underway to determine germline BRCA1/2 status of this patient population, as BRCA1/2 status may also be predictive of immunotherapy response. Taken together, these African ancestry specific phenotypes characterized among patients with TNBC highlight prospective biomarker or therapeutic opportunities for these historically underserved populations.

Citation Format: Rachel Martini, Max Chao, Timothy Chu, Ishmael Kyei, Ernest Adjei, Mahteme Bekele, Paula Ginter, Kofi Gyan, Olivier Elemento, Nicolas Robine, John Carpten, Lisa Newman, Melissa Davis. Multiomics in disparities research: Identifying African ancestry-specific mechanisms in the triple negative breast cancer tumor microenvironment. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr NG03.

Relation of circulating estrogens with hair relaxer and skin lightener use among postmenopausal women in Ghana

BACKGROUND

Hair relaxers and skin lighteners have been commonly used by African women, with suggestions that they may have hormonal activity.

OBJECTIVES

To investigate the relationship of hair relaxer and skin lightener use to serum estrogen/estrogen metabolite levels.

METHODS

We utilized the postmenopausal population-based controls of the Ghana Breast Health Study to estimate adjusted geometric means (GM) and 95% confidence intervals of individual circulating estrogen levels by hair relaxer/skin lightener exposure categories.

RESULTS

Of the 585 postmenopausal women included in our analysis, 80.2% reported hair relaxer use and 29.4% skin lightener use. Ever hair relaxer use was positively associated with estriol (adjusted GM 95.4 pmol/L vs. never 74.5, p value = 0.02) and 16-epiestriol (20.4 vs. 16.8, p value = 0.05) particularly among users of lye-based hair relaxers. Positive associations between scalp burns and unconjugated estrogens were observed (e.g., unconjugated estrone: 5+ scalp burns 76.9 [59.6-99.2] vs. no burns 64.0 [53.7-76.3], p-trend = 0.03). No association was observed between use of skin lighteners and circulating estrogens.

SIGNIFICANCE

This study presents evidence that circulating 16-pathway estrogens (i.e., estriol and 16-epiestriol) may be increased in users of lye-based hair relaxer products. Among hair relaxer users, unconjugated estrogen levels were elevated in women with a greater number of scalp burns.

IMPACT STATEMENT

In this population-based study of hair relaxer and skin lightener use among postmenopausal women in Ghana, altered estrogen metabolism was observed with hair relaxer use, particularly among women using lye-based products or with a greater number of scalp burns. In contrast, skin lightener use was not associated with differences in estrogen metabolism in this population. Continued investigation of the potential biological impact on breast cancer risk of hair relaxer use is warranted.

Neuropathology Outreach in Ghana

Introduction/Objective

Ghana has a population of over 31 million people and approximately 15 neurosurgeons but is currently without a dedicated neuropathologist. Here we present a month of neuropathology outreach performed at the Komfo Anokye Teaching Hospital (KATH) in Kumasi and the Korle-Bu Teaching Hospital (KBTH) in Accra.

Methods/Case Report

In February of 2022, a second-year neuropathology fellow and a board-certified neuropathologist traveled to Ghana to give 40 approximately 1.5 hour neuropathology didactic and interactive teaching sessions. A two-week format of outreach was developed for each site in Ghana and consisted of didactic lectures and interactive sessions covering the WHO 2021 brain tumor classification system, neuroautopsy, neuroinfectious disease, neurodegenerative disease, neuromuscular disease, forensic neuropathology, neurodevelopment, and unknown case conferences. Meanwhile, a pathology trainee worked remotely to organize 12 one-hour virtual general pathology lectures and develop continuing outreach. A survey of 16 questions including 12 multiple choice questions and four short answer questions was used to assess each component and the overall satisfaction of the outreach.

Results (if a Case Study enter NA)

Eight brains were examined at four neuroautopsy conferences and ten case consultations were performed upon request. Survey results showed no statistical differences amongst the 20 sessions. Comments were positive and included one respondent planning to redesign their PhD research to focus on neurodegenerative disease in Ghana and several others commenting on the utility of molecular updates. Suggestions for improvement included quizzes, including more morphology and IHC in lectures, sending digital slides before future visits, teaching spinal cord removal, and the need for continuing outreach in neuropathology, dermatopathology, cytopathology and gynecologic pathology.

Conclusion

This experience provides a useful and well-appreciated approach to delivering international neuropathology outreach. Opportunities in neuropathology on an international level range from educational to clinical practice and research.

The oral microbiome and breast cancer and nonmalignant breast disease, and its relationship with the fecal microbiome in the Ghana Breast Health Study

The oral microbiome, like the fecal microbiome, may be related to breast cancer risk. Therefore, we investigated whether the oral microbiome was associated with breast cancer and nonmalignant breast disease, and its relationship with the fecal microbiome in a case-control study in Ghana. A total of 881 women were included (369 breast cancers, 93 nonmalignant cases and 419 population-based controls). The V4 region of the 16S rRNA gene was sequenced from oral and fecal samples. Alpha-diversity (observed amplicon sequence variants [ASVs], Shannon index and Faith's Phylogenetic Diversity) and beta-diversity (Bray-Curtis, Jaccard and weighted and unweighted UniFrac) metrics were computed. MiRKAT and logistic regression models were used to investigate the case-control associations. Oral sample alpha-diversity was inversely associated with breast cancer and nonmalignant breast disease with odds ratios (95% CIs) per every 10 observed ASVs of 0.86 (0.83-0.89) and 0.79 (0.73-0.85), respectively, compared to controls. Beta-diversity was also associated with breast cancer and nonmalignant breast disease compared to controls (P ≤ .001). The relative abundances of Porphyromonas and Fusobacterium were lower for breast cancer cases compared to controls. Alpha-diversity and presence/relative abundance of specific genera from the oral and fecal microbiome were strongly correlated among breast cancer cases, but weakly correlated among controls. Particularly, the relative abundance of oral Porphyromonas was strongly, inversely correlated with fecal Bacteroides among breast cancer cases (r = -.37, P ≤ .001). Many oral microbial metrics were strongly associated with breast cancer and nonmalignant breast disease, and strongly correlated with fecal microbiome among breast cancer cases, but not controls.

Rational design of an essential diagnostics network to support Universal Health Coverage: a modeling analysis

Background

Diagnostic investigations, including pathology and laboratory medicine (PALM) and radiology, have been largely absent from international strategies such as the Sustainable Development Goals. Further, there is little international guidance on which health system tiers different diagnostics should be placed, a critical step in developing a country-level diagnostics network. We describe a modeling strategy to produce tier-specific diagnostic recommendations based on disease burden, current treatment pathways, and existing infrastructure in a country.

Methods

The relational model assumes that diagnostics should be available at the lowest tier where patients might receive medical management. Using Ghana as an exemplar, the 20 diseases forecasted by 2030 and 2040 to cause the greatest burden in low- and middle-income countries were mapped to three generalized tiers in the Ghanaian health system (Primary, Secondary, and Tertiary care) for three levels of each disease (triage, uncomplicated, and complicated). The lowest tier at which a diagnostic could potentially be placed was restricted by existing infrastructure, though placement still required there be a medical justification for the diagnostic at that tier.

Results

The model recommended 111 unique diagnostic investigations with 17 at Primary tier, an additional 45 at Secondary tier and a further 49 at Tertiary tier. Estimated capital costs were $8,330 at Primary tier and between $571,000 to $777,000 at Secondary tier. Twenty-eight different laboratory tests were recommended as send-outs from Primary to Secondary tier, and twelve as send-outs to Tertiary tier.

Conclusions

This model provides a transparent framework within which countries can customize diagnostic planning to local disease priorities, health system patient treatment pathways, and infrastructural limitations to best support Universal Health Coverage.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12913-022-08558-2.

Polygenic risk scores for prediction of breast cancer risk in women of African ancestry: a cross-ancestry approach

Polygenic risk scores (PRSs) are useful for predicting breast cancer risk, but the prediction accuracy of existing PRSs in women of African ancestry (AA) remains relatively low. We aim to develop optimal PRSs for the prediction of overall and estrogen receptor (ER) subtype-specific breast cancer risk in AA women. The AA dataset comprised 9235 cases and 10 184 controls from four genome-wide association study (GWAS) consortia and a GWAS study in Ghana. We randomly divided samples into training and validation sets. We built PRSs using individual-level AA data by a forward stepwise logistic regression and then developed joint PRSs that combined (1) the PRSs built in the AA training dataset and (2) a 313-variant PRS previously developed in women of European ancestry. PRSs were evaluated in the AA validation set. For overall breast cancer, the odds ratio per standard deviation of the joint PRS in the validation set was 1.34 [95% confidence interval (CI): 1.27-1.42] with the area under receiver operating characteristic curve (AUC) of 0.581. Compared with women with average risk (40th-60th PRS percentile), women in the top decile of the PRS had a 1.98-fold increased risk (95% CI: 1.63-2.39). For PRSs of ER-positive and ER-negative breast cancer, the AUCs were 0.608 and 0.576, respectively. Compared with existing methods, the proposed joint PRSs can improve prediction of breast cancer risk in AA women.

Breast Cancer Risk in Women from Ghana Carrying Rare Germline Pathogenic Mutations

BACKGROUND

Risk estimates for women carrying germline mutations in breast cancer susceptibility genes are mainly based on studies of European ancestry women.

METHODS

We investigated associations between pathogenic variants (PV) in 34 genes with breast cancer risk in 871 cases [307 estrogen receptor (ER)-positive, 321 ER-negative, and 243 ER-unknown] and 1,563 controls in the Ghana Breast Health Study (GBHS), and estimated lifetime risk for carriers. We compared results with those for European, Asian, and African American ancestry women.

RESULTS

The frequency of PV in GBHS for nine breast cancer genes was 8.38% in cases and 1.22% in controls. Relative risk estimates for overall breast cancer were: (OR, 13.70; 95% confidence interval (CI), 4.03-46.51) for BRCA1, (OR, 7.02; 95% CI, 3.17-15.54) for BRCA2, (OR, 17.25; 95% CI, 2.15-138.13) for PALB2, 5 cases and no controls carried TP53 PVs, and 2.10, (0.72-6.14) for moderate-risk genes combined (ATM, BARD1, CHEK2, RAD51C, RAD52D). These estimates were similar to those previously reported in other populations and were modified by ER status. No other genes evaluated had mutations associated at P &lt; 0.05 with overall risk. The estimated lifetime risks for mutation carriers in BRCA1, BRCA2, and PALB2 and moderate-risk genes were 18.4%, 9.8%, 22.4%, and 3.1%, respectively, markedly lower than in Western populations with higher baseline risks.

CONCLUSIONS

We confirmed associations between PV and breast cancer risk in Ghanaian women and provide absolute risk estimates that could inform counseling in Ghana and other West African countries.

IMPACT

These findings have direct relevance for breast cancer genetic counseling for women in West Africa.

Measured body size and serum estrogen metabolism in postmenopausal women: the Ghana Breast Health Study

Background

Several anthropometric measures have been associated with hormone-related cancers, and it has been shown that estrogen metabolism in postmenopausal women plays an important role in these relationships. However, little is known about circulating estrogen levels in African women, and the relevance to breast cancer or breast cancer risk factors. To shed further light on the relationship of anthropometric factors and estrogen levels in African women, we examined whether measured body mass index (BMI), waist-to-hip ratio (WHR), height, and self-reported body size were associated with serum estrogens/estrogen metabolites in a cross-sectional analysis among postmenopausal population-based controls of the Ghana Breast Health Study.

Methods

Fifteen estrogens/estrogen metabolites were quantified using liquid chromatography-tandem mass spectrometry in serum samples collected from postmenopausal female controls enrolled in the Ghana Breast Health Study, a population-based case–control study conducted in Accra and Kumasi. Geometric means (GMs) of estrogens/estrogen metabolites were estimated using linear regression, adjusting for potential confounders.

Results

Measured BMI (≥ 30 vs. 18.5–24.9 kg/m2) was positively associated with parent estrogens (multivariable adjusted GM for unconjugated estrone: 78.90 (66.57–93.53) vs. 50.89 (43.47–59.59), p-value < 0.0001; and unconjugated estradiol: 27.83 (21.47–36.07) vs. 13.26 (10.37–16.95), p-value < 0.0001). Independent of unconjugated estradiol, measured BMI was associated with lower levels of 2-pathway metabolites and higher levels of 16-ketoestradriol. Similar patterns of association were found with WHR; however, the associations were not entirely independent of BMI. Height was not associated with postmenopausal estrogens/estrogen metabolite levels in African women.

Conclusions

We observed strong associations between measured BMI and parent estrogens and estrogen metabolite patterns that largely mirrored relations that have previously been associated with higher breast cancer risk in postmenopausal White women. The consistency of the BMI-estrogen metabolism associations in our study with those previously noted among White women suggests that estrogens likely explain part of the BMI-postmenopausal breast cancer risk in both groups. These findings merit evaluation in Black women, including prospective studies.

COVID-19 in Sub-Saharan Africa: A Multi-Institutional Survey of the Impact of the Global Pandemic on Cancer Care Resources

Purpose/Objective(s)

The COVID-19 pandemic has direct and indirect impact on patients with cancer. Low- and middle-income regions, especially sub-Saharan Africa, are especially vulnerable to a negative impact on cancer resources and outcomes. We report the initial indirect impact of COVID-19 on cancer care in the sub-Saharan Africa region approximately 14 months into the pandemic.

Materials/Methods

At the start of the pandemic, we created a consortium of African and North American cancer centers and NGOs for the distribution of factual and timely information and data on COVID-19 and cancer care. A survey was distributed to consortium members and other colleagues from the sub-Saharan Africa region to understand the impact of COVID-19 in cancer care resources. Survey respondents represent cancer experts from 8 centers in Ghana, Nigeria, Kenya, Ethiopia, South Africa, Rwanda, and Zimbabwe.

Results

All sites report SARS-COv-2 transmission amongst cancer patients and staff. A total of 48 staff developed COVID-19 infection with one site reporting a single death. Additionally, 62.5% of sites report loss of oncology physician or nursing staff due to redeployment for COVID-19 care resulting in minimal (20%), moderate (60%), or other (20%) impact on cancer care. All 8 sites report a government mandated lockdown with a median duration of 2.3 months (IQR .9-4.2 months). Impact of the lockdown on cancer care was reported as none (12.5%), minimal (12.5%), moderate (50%) and severe (25%). Additionally, we surveyed the impact of COVID-19 on resources in radiation, medical and surgical oncology services. A total of 25% of responders reported decreases in radiation resources while 37.5% reported changes in medical and surgical oncology resources. For radiation oncology, the most common impact was access to CT imaging for 3D-conformal planning (25%), access to brachytherapy (12.5%), and medical physics support (12.5%). For medical oncology, the most frequent impact was access to chemotherapy (37.5%) and blood products (12.5%), and loss of oncology ward space (12.5%). The most frequent impact for surgical oncology was access to operating rooms (37.5%), ventilators (12.5%), anesthesia (25%), blood products (25%), and other supply chain issues (25%). Of centers who reported impact on cancer care, severity of impact was none (50%) and moderate (50%) for radiation oncology; mild (25%) and moderate (75%) for medical oncology; and moderate (75%) and severe (25%) for surgical oncology.

Conclusion

Our survey identified diffuse impact of COVID-19 on all facets of cancer care across sub-Saharan Africa. Based on physician assessment of impact, the discipline of surgical oncology may be impacted the greatest. Additional studies measuring the impact of COVID-19 on cancer outcomes are ongoing.

Circulating tumor DNA is readily detectable among Ghanaian breast cancer patients supporting non-invasive cancer genomic studies in Africa

Circulating tumor DNA (ctDNA) sequencing studies could provide novel insights into the molecular pathology of cancer in sub-Saharan Africa. In 15 patient plasma samples collected at the time of diagnosis as part of the Ghana Breast Health Study and unselected for tumor grade and subtype, ctDNA was detected in a majority of patients based on whole- genome sequencing at high (30×) and low (0.1×) depths. Breast cancer driver copy number alterations were observed in the majority of patients.

Giant primary scrotal lipoma in a low-resource setting: challenges with diagnosis and review of literature

Lipoma is the commonest benign mesenchymal tumor composed of matured adipocytes. A literature search revealed few reported cases of giant scrotal lipoma. This article aims to report a giant scrotal lipoma weighing 1100 g and illustrate our challenges with the diagnostic process in a low-resource setting. A 28-year-old male presented with a huge right scrotal mass. Examination revealed the mass had no cough impulse. It was firm, non-tender and lobulated, with definite edges. Scrotal sonography was suspicious of lipoma. Intraoperatively, there was an encapsulated scrotal wall mass and an incidental inguinoscrotal hernia, content being the omentum. The scrotal mass was excised, hernia sac was ligated, and excised and the posterior wall was repaired. Histology confirmed the scrotal mass as a lipoma. Primary scrotal lipomas are rare but should be considered in the differential diagnosis of unusual scrotal masses. Ultrasonography is a useful diagnostic tool in resource-limited settings.

Abstract 81: Studying Ghanian Cancer Genomes Using Cell-free DNA

Purpose: Analysis of cell free DNA could provide a rapid and non-invasive approach to detect cancer and provide new molecular insights in many African countries where expert pathology is lacking. Hence, we tested whether whole-genome sequencing of cfDNA (WGS-cfDNA) could identify somatic alterations that drive breast cancer.

Methods: We conducted a pilot on 15 Ghanaian women (median age 49.5 years) recruited as part of the Ghana Breast Health Study. cfDNA was extracted and subjected to WGS at 30x and 0.1x. ichorCNA software was used to predict copy number alterations and ctDNA fractions.

Results: We found extensive amplification and deletion of multiple chromosomal regions including those with oncogenes and tumor suppressor genes associated with breast cancer. Similar copy number alterations for selected breast cancer genes were observed with 0.1x and 30x cfDNA-WGS with increasing concordance between the two instruments as the ctDNA fraction increases. We observed a high frequency (&gt;50%) of copy number gain in 3/5 regions and potential target genes for the amplification (chr8p11-12 [ZNF703] n=8, 53.3%; chr8q24.2 [MYC] n=9, 60%; chr19q12 [CCNE1] n=9, 60%), which were in agreement to previous observations among African-American (AA) ancestry compared to European-American (EA) ancestry in TCGA datasets.

Conclusion: Our data provided evidence that ctDNA-based genomic studies are possible and ctDNA analysis could be a tool for future molecular oncology studies in Africa for cancer etiology, surveillance and clinical trials.

Citation Format: Samuel Ahuno, Anna-Lisa Doebley, Thomas Ahearn, Joel Yarney, Nicholas Titiloye, Nancy Hamel, Ernest Adjei, Joe-Nat Clegg-Lamptey, Lawrence Edusei, Baffour Awuah, Xiaoyu Song, Verne Vanderpuye, Mustapha Abubakar, Maire Duggan, Daniel Stover, Kofi Nyarko, John Bartlet, Francis Aitpillah, Daniel Ansong, Kevin Gardner, Anne Bowcock, Carlos Caldas, William Foulkes, Seth Wiafe, Wiafe-Addai, Montserrat Garcia-Closas, Alexander Kwarteng, Gavin Ha, Jonine Figueroa, Paz Polak, On Behalf Of Ghana Breast Health Study Team. Studying Ghanian Cancer Genomes Using Cell-free DNA [abstract]. In: Proceedings of the 9th Annual Symposium on Global Cancer Research; Global Cancer Research and Control: Looking Back and Charting a Path Forward; 2021 Mar 10-11. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2021;30(7 Suppl):Abstract nr 81.

Multiethnic PDX models predict a possible immune signature associated with TNBC of African ancestry

PURPOSE

Triple-negative breast cancer (TNBC) is an aggressive subtype most prevalent among women of Western Sub-Saharan African ancestry. It accounts for 15-25% of African American (AA) breast cancers (BC) and up to 80% of Ghanaian breast cancers, thus contributing to outcome disparities in BC for black women. The aggressive biology of TNBC has been shown to be regulated partially by breast cancer stem cells (BCSC) which mediate tumor recurrence and metastasis and are more abundant in African breast tumors.

METHODS

We studied the biological differences between TNBC in women with African ancestry and those of Caucasian women by comparing the gene expression of the BCSC. From low-passage patient derived xenografts (PDX) from Ghanaian (GH), AA, and Caucasian American (CA) TNBCs, we sorted for and sequenced the stem cell populations and analyzed for differential gene enrichment.

RESULTS

In our cohort of TNBC tumors, we observed that the ALDH expressing stem cells display distinct ethnic specific gene expression patterns, with the largest difference existing between the GH and AA ALDH+ cells. Furthermore, the tumors from the women of African ancestry [GH/AA] had ALDH stem cell (SC) enrichment for expression of immune related genes and processes. Among the significantly upregulated genes were CD274 (PD-L1), CXCR9, CXCR10 and IFI27, which could serve as potential drug targets.

CONCLUSIONS

Further exploration of the role of immune regulated genes and biological processes in BCSC may offer insight into developing novel approaches to treating TNBC to help ameliorate survival disparities in women with African ancestry.

Abstract PO-093: Circulating tumor DNA (ctDNA) from peripheral blood is detectable among Ghanaian breast cancer patients

Cancer incidence is rising and mortality rates are high in Africa, where access to molecular pathology is limited. Analysis of cancer-related mutations in circulating tumor DNA (ctDNA) from cell-free DNA (cfDNA) that is shed into the bloodstream by tumor cells could be transformative to the African continent and provide new molecular insights. Using samples collected from the Ghana Breast Health Study we tested whether whole-genome sequencing (WGS) of cfDNA could detect ctDNA and identify somatic alterations that drive breast cancer. We selected 15 breast cancer patients (median age 49.5 years) with duplicated plasma samples. Pathologic grade, age, and immunohistochemical (IHC) stains for estrogen receptor (ER), progesterone receptor (PR) and HER2 were available for the majority of patients (&gt;80%). cfDNA extraction and WGS at 30x and 0.1x was performed. ichorCNA software was used on Next Generation Sequencing (NGS) read counts to estimate the ctDNA fraction and predict copy number alteration profiles. High depth 30x cfDNA-WGS analysis showed that all 15 breast cancer patients had 1% ctDNA or greater (median[IQR] 3.96%[2.22%-8.13%]). There was high concordance between estimated ctDNA fraction using 0.1x and 30x WGS (Pearson r = 0.9). Copy number profiling showed extensive amplification and deletion of multiple chromosomal regions containing important cancer genes (such as MYC, PIK3CA, TERT, and GATA3). Of the four patients classified as HER2 positive based on IHC, two had increased ERBB2 copy number (50 and 3 copies, respectively). Our data provide evidence that ctDNA-based genomic studies are possible and ctDNA analysis could be a tool for future molecular oncology studies in Africa for cancer etiology, surveillance and clinical trials.

Citation Format: Samuel T. Ahuno, Lawrence Edusei, Nicolas Titiloye, Ernest Adjei, Joe-Nat Clegg-Lamptey, Joel Yarney, Beatrice Wiafe-Addai, Baffour Awuah, Verne Vanderpuye, Maire Duggan, Seth Wiafe, Kofi Nyarko, Francis Aitpillah, Daniel Ansong, Thomas Ahearn, Alexander Kwarteng, Mustapha Abubakar, Montserrat Garcia-Closas, Gavin Ha, Jonine D. Figueroa, Paz Polak, on behalf of the Ghana Breast Health Study Team. Circulating tumor DNA (ctDNA) from peripheral blood is detectable among Ghanaian breast cancer patients [abstract]. In: Proceedings of the AACR Virtual Conference: Thirteenth AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2020 Oct 2-4. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2020;29(12 Suppl):Abstract nr PO-093.

Familial adenomatous polyposis: a case study

Familial adenomatous polyposis (FAP) is an inherited syndrome characterized by several adenomatous polyps of the gastrointestinal (GI) mucosa. If treatment is not provided, an average individual with classic FAP will develop colorectal carcinoma around the age of 40 years. The incidence rate of FAP in developing countries like Ghana is unknown compared to advanced countries. We present the first FAP case of a 22-year-old Ghanaian female who presented with massive lower GI bleeding and underwent surgical management after a thorough investigation. The initial assumption that colonic polyps are scarce in native Africans may be more than what is perceived. This highlights the need for the availability of endoscopic services in Ghana.

Reproductive factors and risk of breast cancer by tumor subtypes among Ghanaian women: A population-based case-control study

Higher proportions of early-onset and estrogen receptor (ER) negative cancers are observed in women of African ancestry than in women of European ancestry. Differences in risk factor distributions and associations by age at diagnosis and ER status may explain this disparity. We analyzed data from 1,126 cases (aged 18-74 years) with invasive breast cancer and 2,106 controls recruited from a population-based case-control study in Ghana. Odds ratios (OR) and 95% confidence intervals (CI) were estimated for menstrual and reproductive factors using polytomous logistic regression models adjusted for potential confounders. Among controls, medians for age at menarche, parity, age at first birth, and breastfeeding/pregnancy were 15 years, 4 births, 20 years and 18 months, respectively. For women ≥50 years, parity and extended breastfeeding were associated with decreased risks: >5 births vs. nulliparous, OR 0.40 (95% CI 0.20-0.83) and 0.71 (95% CI 0.51-0.98) for ≥19 vs. <13 breastfeeding months/pregnancy, which did not differ by ER. In contrast, for earlier onset cases (<50 years) parity was associated with increased risk for ER-negative tumors (p-heterogeneity by ER = 0.02), which was offset by extended breastfeeding. Similar associations were observed by intrinsic-like subtypes. Less consistent relationships were observed with ages at menarche and first birth. Reproductive risk factor distributions are different from European populations but exhibited etiologic heterogeneity by age at diagnosis and ER status similar to other populations. Differences in reproductive patterns and subtype heterogeneity are consistent with racial disparities in subtype distributions.

Androgen Receptor and ALDH1 Expression Among Internationally Diverse Patient Populations

Purpose

Population-based incidence rates of breast cancers that are negative for estrogen receptor (ER), progesterone receptor, and human epidermal growth factor receptor 2/neu (triple-negative breast cancer [TNBC]) are higher among African American (AA) compared with white American (WA) women, and TNBC prevalence is elevated among selected populations of African patients. The extent to which TNBC risk is related to East African versus West African ancestry, and whether these associations extend to expression of other biomarkers, is uncertain.

Methods

We used immunohistochemistry to evaluate estrogen receptor, progesterone receptor, human epidermal growth factor receptor 2/neu, androgen receptor and aldehyde dehydrogenase 1 (ALDH1) expression among WA (n = 153), AA (n = 76), Ethiopian (Eth)/East African (n = 90), and Ghanaian (Gh)/West African (n = 286) patients with breast cancer through an institutional review board–approved international research program.

Results

Mean age at diagnosis was 43, 49, 60, and 57 years for the Eth, Gh, AA, and WA patients, respectively. TNBC frequency was higher for AA and Gh patients (41% and 54%, respectively) compared with WA and Eth patients (23% and 15%, respectively; P < .001) Frequency of ALDH1 positivity was higher for AA and Gh patients (32% and 36%, respectively) compared with WA and Eth patients (23% and 17%, respectively; P = .007). Significant differences were observed for distribution of androgen receptor positivity: 71%, 55%, 42%, and 50% for the WA, AA, Gh, and Eth patients, respectively (P = .008).

Conclusion

Extent of African ancestry seems to be associated with particular breast cancer phenotypes. West African ancestry correlates with increased risk of TNBC and breast cancers that are positive for ALDH1.

Abstract 622: Reproductive factors and breast cancer risk to women in Ghana, West Africa

Background: Women of African ancestry have a higher proportion of early onset and estrogen receptor (ER) negative cancers compared to women of European descent. Differences in risk associations by age at onset and ER status for reproductive factors, particularly parity and breastfeeding, have been proposed as possible contributors to this racial disparity. We therefore investigated these relations in the Ghana Breast Health Study.

Methods: The study population included 1,126 women diagnosed with invasive breast cancer and 2,106 population controls aged 18-74 years at recruitment (2013-2015) in three hospitals in Accra and Kumasi, Ghana. Factors evaluated included age at menarche, number of livebirths, age at first livebirth, and median months breastfeeding per pregnancy. Odds ratios (OR) and 95% confidence intervals (CI) were estimated using logistic regression models overall and stratified by age. Associations by ER status were estimated using polytomous logistic regression models.

Results: We observed associations with parity and extended breastfeeding duration per pregnancy that were modified by age at onset (&lt;50 vs. &gt;50 years, P-het &lt;0.02 and 0.01, respectively). For women &lt;50 years, the OR was 0.70 (95% CI 0.42-1.18) for those with &gt;5 v. 0 livebirths, but there was no association with breastfeeding months per pregnancy (&gt;18 vs &lt;12 months: OR (95%CI) = 1.04 (0.75-1.44). For women &gt;50 years, both higher number of livebirths and longer durations of breastfeeding months per pregnancy were associated with lower breast cancer risk: OR (95%CI) = 0.40 (0.20-0.83) for &gt;5 vs 0 livebirths and 0.71 (0.51-0.98) for &gt;18 vs &lt;12 breastfeeding months per pregnancy. Data were consistent with a higher risk of early onset (&lt;50 years) ER-negative breast cancer for parous compared to nulliparous women (1.63 (0.82-3.25), that was attenuated by extended breastfeeding (0.72 (0.45-1.14) for &gt;18 vs &lt;12 breastfeeding months per pregnancy).

Conclusion: In this population of women in West Africa, increased number of live births and breastfeeding months per pregnancy were strong protective factors for later onset breast cancer. Among younger women, these trends were modified by ER status, with opposite associations for parity in ER+ vs. ER- tumors and an inverse association with breastfeeding in the ER- tumors that was not seen in the ER+ tumors. Our data support previous reports in African-American women of differential associations of parity and breastfeeding by ER status and age at onset. Further attention should focus on how reproductive factors contribute to observed racial heterogeneity in breast cancer.

Citation Format: Jonine D. Figueroa, Brittny Davis Lynn, Lawrence Edusei, Nicolas Titiloye, Ernest Adjei, Joe Nat Clegg-Lamptey, Beatrice Wiafe-Addai, Baffour Awuah, Montserrat Garcia-Closas, Louise A. Brinton. Reproductive factors and breast cancer risk to women in Ghana, West Africa [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 622.

Clinical characteristics, HIV status, and molecular biomarkers in squamous cell carcinoma of the conjunctiva in Ghana

BACKGROUND AND AIMS

Conjunctival squamous cell carcinoma (CSCC) varies in incidence geographically from 0 to 1 case per 100 000 per year globally. Additionally, the incidence of CSCC is known to increase 49% for every 10° decrease in latitude. Since the onset of the AIDS epidemic, there has been a trend of increasing incidence of CSCC in Africa, and despite relatively stable levels of ultraviolet (UV) exposure, there is an observed 12 times greater risk of developing CSCC when individuals are infected with HIV. In this study, we aim to analyze the clinical characteristics and biomarkers of CSCC in Ghana.

METHODS

In this study, a registry review of patients from January 2011 to May 2016 with CSCC at Komfo-Anokye Teaching Hospital in Kumasi, Ghana, was performed (n = 64). Tumor blocks of the CSCC were analyzed for the expression of various biomarkers.

RESULTS

In this study, the median age of onset of CSCC is 46.5 years old (range of 20-90 y old). Fifty one and a half percent (n = 33) of the cohort is female. There is a low rate of smoking and alcohol use in our CSCC cohort. Thirty-nine percent (n = 12) of Ghanaian men with CSCC are HIV-, while only 12% (n = 4) of women are HIV-. Fifteen patients had metastasis to lymph nodes or other tissues, and we observed a statistically significant relationship between HIV infection and metastasis (P = 0.027, chi-squared test). We observed no statistically significant relationship between known prognostic CSCC biomarkers and HIV status, age, or tumor stage.

CONCLUSION

Better characterization of CSCC could have a profound impact on the prevention, early identification, and treatment of CSCC in Africa. A retrospective chart analysis and collection of tumor samples can be challenging in this region due to methods of record keeping and stigma attached to clinical data such as HIV testing and smoking and alcohol use. As a result, in this study, data were often incomplete leading to inconclusive results and analysis that should be interpreted with caution. Future studies should consider a prospective study design that gathers clinical data in a standardized format and ensures fresh tissue from CSCC tumors.

Skin lighteners and hair relaxers as risk factors for breast cancer: results from the Ghana breast health study

Skin lighteners and hair relaxers, both common among women of African descent, have been suggested as possibly affecting breast cancer risk. In Accra and Kumasi, Ghana, we collected detailed information on usage patterns of both exposures among 1131 invasive breast cancer cases and 2106 population controls. Multivariate analyses estimated odds ratios (ORs) and 95% confidence intervals (CIs) after adjustment for breast cancer risk factors. Control usage was 25.8% for ever use of skin lighteners and 90.0% for use of hair relaxers for >1 year. The OR for skin lighteners was 1.10 (95% CI 0.93-1.32), with higher risks for former (1.21, 0.98-1.50) than current (0.96, 0.74-1.24) users. No significant dose-response relations were seen by duration, age at first use or frequency of use. In contrast, an OR of 1.58 (95% CI 1.15-2.18) was associated with use of hair relaxers, with higher risks for former (2.22, 1.56-3.16) than current (1.39, 1.00-1.93) users. Although numbers of burns were inconsistently related to risk, associations increased with duration of use, restricted to women who predominately used non-lye products (P for trend < 0.01). This was most pronounced among women with few children and those with smaller tumors, suggesting a possible role for other unmeasured lifestyle factors. This study does not implicate a substantial role for skin lighteners as breast cancer risk factors, but the findings regarding hair relaxers were less reassuring. The effects of skin lighteners and hair relaxers on breast cancer should continue to be monitored, especially given some biologic plausibility for their affecting risk.

Creating Models to Identify New Therapeutic Options for Aggressive African Breast Cancers

Background: Population-based incidence rates of breast cancer (BC) that does not express the estrogen receptor (ER), progesterone receptor (PR) or overexpress the human epidermal growth factor 2 HER2/ neu (triple negative breast cancer, TNBC) are higher among Africans compared with white women. However the underlying biologic and genetic differences among different ethnicities are poorly understood and there are currently very few ethnically diverse BC models available for identifying new therapeutic options. Aim: Establish an international collaboration to: i, characterize African breast tumors ii, create models for studying these tumors and iii, identify biomarkers for early detection and treatment personalization. Methods: We have collected tumors from 154 white Americans WA, 76 African Americans, AA, 190 Ethiopians, Eth, and 286 Ghanaian (Gh) BC patients. We then established a unique resource of patient derived xenografts (PDX) from these tumors. The PDXs were then fully characterized using whole exome and RNA sequencing for the primary tumor, matched normal DNA, and corresponding low passage PDXs. Using immunohistochemistry, we evaluated the ER, PR, HER2/ neu, androgen receptor (AR), and ALDH1 (cancer stem cell marker) expression among these tumors. Based on biomarker expression the PDXs were then tested against a panel of IND drugs, either alone or in combinations, in an ex vivo organoid culture system to discover potential new therapeutic options. Results: Mean age at BC diagnosis was 43; 49; 60; and 57 years for the Eth; Gh; AA; and WA patients, respectively. The proportion of TNBC was significantly higher for the AA and Gh patients (41% and 54%, respectively) compared with the WA and Eth patients (23% and 15%, respectively); P < 0.001. Significant differences were observed for distribution of AR positivity, which was 71%; 55%; 42% and 50% for the WA; AA; Gh; and Eth cases, respectively ( P = 0.008). The Gh breast tumors exhibited the highest number of loss of function and missense mutations that are likely to impact therapy with a high frequency of P53, APC, and FGFR mutations. These mutations were maintained in the corresponding PDXs that were developed, and were thus used as biomarkers for drug screening. These tumors exhibited a gene expression signature based on the ethnicity of the patients with 2385 genes differentially expressed between Gh and AA, 1573 between AA and CA and 1317 between GH and CA. Results from our ongoing drug screening and biomarker identification will be available soon. Conclusions: Establishing the molecular and genetic platform of aggressive breast cancers occurring in women with African ancestry will help in identifying biomarkers for early cancer detection and targeted treatment stratification for optimum patient outcome. The availability of tumor models based on tumors from diverse African populations is the important missing pieces that have to be incorporated into current drug discovery efforts.

Abstract P6-07-01: Withdrawn

This abstract was withdrawn by the authors.

Mucin expression patterns in histological grades of colonic cancers in Ghanaian population

Introduction

Myriad roles of mucins in normal tissues have been well documented, including lubrication of the epithelial surfaces; protection from physical damage; facilitation in cell-cell signaling and suppression of inflammatory activity. Pathological expression of mucins has been noted in cancer development and progression. This study sought to identify and quantify the types of mucins produced during various histological grades of colon cancer and to assess the diagnostic significance.

Methods

Formalin fixed, paraffin-embedded tissue blocks, comprising three (3) normal colon and twenty-two (22) colon cancer tissues, were retrieved from the archives of the histopathology department of the Komfo Anokye Teaching Hospital. They were stained with Haematoxylin and eosin (H&E) for diagnosis and grading of tumours. Tissues were pre-digested with diastase and stained with Alcian blue (pH 2.5)/Periodic Acid Schiff to characterize the mucin variants present.

Results

Our findings indicated that normal colonic tissues expressed exceptionally high amount of acid mucin and low amount of neutral mucin. However, there was a general decrease in mucin expression in colon cancers compared to normal colon tissues. Additional findings suggested that as cancer progresses from low grade to high grade of adenocarcinoma of the colon, there was generally a considerable decrease in the acid mucin production and an increase in the neutral mucin expression. In contrast, a sizeable subpopulation of high-grade adenocarcinomas of colon showed a rather opposite mucin expression pattern- increase in acid mucin and a decrease in neutral mucin.

Conclusion

As colonic cancer progresses, there are corresponding changes in the mucin types and content such that there are decrease in acid mucin and increase in neutral mucin expressions.

Beyond triple-negative breast cancer and African ancestry: Tumor phenotypes among internationally diverse patient populations

1101

Background: Population-based incidence rates of breast cancers that are negative for estrogen receptor (ER), progesterone receptor (PR), and HER2/ neu(triple negative breast cancer {TNBC}) are higher among African American (AA) compared to White American (WA) women. Several studies show higher TNBC frequency among selected populations of African patients. The colonial-era trans-Atlantic slave trade resulted in shared West African ancestry between contemporary AA and Ghanaian (Gh) populations. The extent to which TNBC susceptibility is related to East African versus West African ancestry, and whether these associations extend to expression of other biomarkers such as Androgen Receptor (AR) and mammary stem cell marker ALDH1 is unknown. Methods: We used immunohistochemistry to assess ER, PR, HER2/ neu, AR and ALDH1 among WA (n = 153); AA (n = 76); Ethiopian (Eth)/East African (n = 90) and (Gh)/West African (n = 286) breast cancers through an IRB-approved international research program. Results: Mean age at breast cancer diagnosis was 43; 49; 60; and 57 years for the Eth; Gh; AA; and WA patients, respectively. Frequency of TNBC was significantly higher for AA and Gh patients (54% and 41%, respectively) compared to WA and Eth patients (23% and 15%, respectively); p < 0.001. These associations were unchanged when limited to patients age 50 and younger (47% and 49% for AA and Gh, respectively; versus 18% and 16% for WA and Eth, respectively); p < 0.001. Frequency of ALDH1 positivity was also higher for tumors from AA and Gh patients (32% and 36%, respectively) compared to those from WA and Eth patients (23% and 17%, respectively); p = 0.007. Significant differences were observed for distribution of AR positivity, which was 71%; 55%; 42% and 50% for the WA; AA; Gh; and Eth cases, respectively (p = 0.008). Conclusions: We found a correlation between extent of African ancestry and risk of particular BC phenotypes. West African ancestry was associated with increased risk of TNBC and breast cancers that are positive for ALDH1. Future studies of hereditary TNBC susceptibility among women with African ancestry are warranted.

Design considerations for identifying breast cancer risk factors in a population-based study in Africa

Although breast cancer is becoming more prevalent in Africa, few epidemiologic studies have been undertaken and appropriate methodologic approaches remain uncertain. We therefore conducted a population-based case-control study in Accra and Kumasi, Ghana, enrolling 2,202 women with lesions suspicious for breast cancer and 2,161 population controls. Biopsy tissue for cases prior to neoadjuvant therapy (if given), blood, saliva and fecal samples were sought for study subjects. Response rates, risk factor prevalences and odds ratios for established breast cancer risk factors were calculated. A total of 54.5% of the recruited cases were diagnosed with malignancies, 36.0% with benign conditions and 9.5% with indeterminate diagnoses. Response rates to interviews were 99.2% in cases and 91.9% in controls, with the vast majority of interviewed subjects providing saliva (97.9% in cases vs. 98.8% in controls) and blood (91.8% vs. 82.5%) samples; lower proportions (58.1% vs. 46.1%) provided fecal samples. While risk factor prevalences were unique as compared to women in other countries (e.g., less education, higher parity), cancer risk factors resembled patterns identified elsewhere (elevated risks associated with higher levels of education, familial histories of breast cancer, low parity and larger body sizes). Subjects with benign conditions were younger and exhibited higher socioeconomic profiles (e.g., higher education and lower parity) than those with malignancies, suggesting selective referral influences. While further defining breast cancer risk factors in Africa, this study showed that successful population-based interdisciplinary studies of cancer in Africa are possible but require close attention to diagnostic referral biases and standardized and documented approaches for high-quality data collection, including biospecimens.

Factors contributing to delays in diagnosis of breast cancers in Ghana, West Africa

BACKGROUND

Late diagnoses and poor prognoses of breast cancer are common throughout Africa.

METHODS

To identify responsible factors, we utilized data from a population-based case-control study involving 1184 women with breast malignancies conducted in three hospitals in Accra and Kumasi, Ghana. Interviews focused on potential breast cancer risk factors as well as factors that might contribute to presentation delays. We calculated odds ratios (OR) and 95% confidence intervals (CI) comparing malignances with biopsy masses larger than 5 cm. (62.4% of the 1027 cases with measurable lesions) to smaller lesions.

RESULTS

In multivariate analyses, strong predictors of larger masses were limited education (OR 1.96, 95% CI 1.32-2.90 <primary vs. ≥senior secondary school), being separated/divorced or widowed (1.75, 1.18-2.60 and 2.25, 1.43-3.55, respectively, vs. currently married), delay in care seeking after onset of symptoms (2.64, 1.77-3.95 for ≥12 vs. ≤2 months), care having initially been sought from someone other than a doctor/nurse (1.86, 0.85-4.09), and frequent use of herbal medications/treatment (1.51, 0.95-2.43 for ≥3x/day usage vs. none). Particularly high risks associated with these factors were found among less educated women; for example, women with less than junior secondary schooling who delayed seeking care for breast symptoms for 6 months or longer were at nearly 4-times the risk of more educated women who promptly sought assistance.

CONCLUSIONS

Our findings suggest that additional communication, particularly among less educated women, could promote earlier breast cancer diagnoses. Involvement of individuals other than medical practitioners, including traditional healers, may be helpful in this process.

Extra gonadal sclerosing stromal tumour in the transverse mesocolon

Sclerosing stromal tumour (SST) is a rare benign sex cord stromal tumour of the ovary. We report a case of sclerosing stromal tumour of the mesentery in a 32-year-old Para one who presented with intra abdominal mass, menstrual irregularity and secondary infertility. Histopathology and immunohistochemistry of the completely excised tumour was consistent with sclerosing stromal tumour, immunoreactive only to vimentin. No ovarian tissue was found in the sectioned tumour. Her menses became regular and she conceived 3 months after complete excision and delivered after 9 months. Hormonal assay was not done because SST was least suspected. From literature this is the first case of SST in the transverse mesocolon reported in the West African subregion, and may probably be one of the rare cases of hormonally active SST.

Comparative Analysis of Breast Cancer Phenotypes in African American, White American, and West Versus East African patients: Correlation Between African Ancestry and Triple-Negative Breast Cancer

INTRODUCTION

Triple-negative breast cancer (TNBC) is more common among African American (AA) and western sub-Saharan African breast cancer (BC) patients compared with White/Caucasian Americans (WA) and Europeans. Little is known about TNBC in east Africa.

METHODS

Invasive BC diagnosed 1998-2014 were evaluated: WA and AA patients from the Henry Ford Health System in Detroit, Michigan; Ghanaian/west Africans from the Komfo Anokye Teaching Hospital in Kumasi, Ghana; and Ethiopian/east Africans from the St. Paul's Hospital Millennium Medical College in Addis Ababa, Ethiopia. Histopathology and immunohistochemistry for estrogen receptor (ER), progesterone receptor (PR), and HER2/neu expression was performed in Michigan on formalin-fixed, paraffin-embedded samples from all cases.

RESULTS

A total of 234 Ghanaian (mean age 49 years), 94 Ethiopian (mean age 43 years), 272 AA (mean age 60 years), and 321 WA (mean age 62 years; p = 0.001) patients were compared. ER-negative and TNBC were more common among Ghanaian and AA compared with WA and Ethiopian cases (frequency ER-negativity 71.1 and 37.1 % vs. 19.8 and 28.6 % respectively, p < 0.0001; frequency TNBC 53.2 and 29.8 % vs. 15.5 and 15.0 %, respectively, p < 0.0001). Among patients younger than 50 years, prevalence of TNBC remained highest among Ghanaians (50.8 %) and AA (34.3 %) compared with WA and Ethiopians (approximately 16 % in each; p = 0.0002).

CONCLUSIONS

This study confirms an association between TNBC and West African ancestry; TNBC frequency among AA patients is intermediate between WA and Ghanaian/West Africans consistent with genetic admixture following the west Africa-based trans-Atlantic slave trade. TNBC frequency was low among Ethiopians/East Africans; this may reflect less shared ancestry between AA and Ethiopians.

Breast Cancer and African Ancestry: Lessons Learned at the 10-Year Anniversary of the Ghana-Michigan Research Partnership and International Breast Registry

Women with African ancestry in western, sub-Saharan Africa and in the United States represent a population subset facing an increased risk of being diagnosed with biologically aggressive phenotypes of breast cancer that are negative for the estrogen receptor, the progesterone receptor, and the HER2/neu marker. These tumors are commonly referred to as triple-negative breast cancer. Disparities in breast cancer incidence and outcome related to racial or ethnic identity motivated the establishment of the International Breast Registry, on the basis of partnerships between the Komfo Anokye Teaching Hospital in Kumasi, Ghana, the University of Michigan Comprehensive Cancer Center in Ann Arbor, Michigan, and the Henry Ford Health System in Detroit, Michigan. This research collaborative has featured educational training programs as well as scientific investigations related to the comparative biology of breast cancer in Ghanaian African, African American, and white/European American patients. Currently, the International Breast Registry has expanded to include African American patients throughout the United States by partnering with the Sisters Network (a national African American breast cancer survivors' organization) and additional sites in Ghana (representing West Africa) as well as Ethiopia (representing East Africa). Its activities are now coordinated through the Henry Ford Health System International Center for the Study of Breast Cancer Subtypes. Herein, we review the history and results of this international program at its 10-year anniversary.

Abstract P6-12-14: Comparative analysis of breast cancer phenotypes in African American, White American, and African patients- Correlation between African ancestry and triple negative breast cancer

Introduction: Population-based incidence rates of triple negative breast cancer (TNBC) are higher for African American (AA) compared to White American (WA) women, but it is unclear whether TNBC risk is genetically associated with African ancestry because AA women represent an ancestrally admixed population. Higher frequencies of TNBC have also been observed in sub-Saharan African breast cancer (BC) patients, but comparative analyses of biomarker expression among datasets that include AA, WA, and African women are sparse. We report findings from an international registry that features specimens from a diverse patient population in Detroit, Michigan as well as a hospital in Kumasi, Ghana.

Methods: The study dataset included formalin-fixed, paraffin-embedded invasive BC tumors diagnosed between 1998 and 2014 at the Komfo Anokye Teaching Hospital in Ghana and the prospectively-maintained/annotated Henry Ford Health System cohort in Michigan. All Ghanaian tumors underwent pathology confirmation and immunohistochemistry for estrogen receptor (ER), progesterone receptor (PR) and HER2/neu expression at the University of Michigan. Women were classified into five BC phenotypes and dichotomized into two age groups, &lt;50 and ≥50 years. Polychotomous multivariate GLM models were developed to estimate the risk for each BC phenotype. Statistical analyses were performed in SAS v. 9.0 (Carey, NC). This research was approved by the Institutional Review Boards of the participating institutions.

Results: A total of 234 Ghanaian cases with mean age 49 years (range 24-92); 271 AA with mean age 60 (range 27-87); and 321 WA with mean age 62 (range 31-91) (P=0.001) contributed to this study. Prevalence of histologic grade 3 was lowest in WA (n=107, 33.7%) which was statistically significant from the observed prevalence in AA (n=135, 50.4%) and Ghanaians (n=84, 53.8%) (P&lt;0.0001). ER-negative and TNBC were more common among Ghanaian and AA compared to WA cases (frequency ER-negativity 67.5%, 37.1%, and 19.8%, respectively, p&lt;0.0001; frequency TNBC 53.2%, 29.8%, and 15.5%, respectively, p&lt;0.0001). In the age group &lt;50 years, 82 women (42.5%) were diagnosed with ER+/PR+/HER2-, 65 (33.7%) with TNBC, 27 (14.0%) with ER+/PR+/HER2+, 14 (7.2%) with ER-/PR-/HER2+ and 5(2.6%) with ER-/PR+/HER2- phenotypes. In this young age group, prevalence of TNBC remained highest among Ghanaian women (50.8%), followed by AA (34.3%) and WA (15.9%); (P=.0006). In contrast, highest prevalence of ER+/PR+/HER2+ and ER+/PR+/HER2- phenotypes was observed in WA, followed by AA and Ghanaians. On multivariate analysis histologic grade 3 and racial heritage remained statistically significantly associated with the TNBC phenotype (OR for AA vs. WA with TNBC 1.87, 95% CI 1.15-3.04; OR for Ghanaian vs. WA with TNBC 10.63, 95% CI 5.32-21.25; OR for Grade 3 vs Grade 1 histology with TNBC 33.3, 95% CI 13.45-82.4).

Conclusions: This study confirms an association between the TNBC phenotype and African ancestry; furthermore, extent of African ancestry appears to be associated with an increased likelihood of having a TNBC tumor, since frequency of TNBC among AA patients was intermediate between WA and Ghanaian patients.

Citation Format: Newman LA, Jiagge E, Bensenhaver JM, Chitale D, Kleer C, Merajver S, Kyei I, Aitpillah F, Oppong J, Amankwaa-Frempong E, Adjei E, Wicha M, Awuah B, Stark A. Comparative analysis of breast cancer phenotypes in African American, White American, and African patients- Correlation between African ancestry and triple negative breast cancer. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P6-12-14.

Characterizing Breast Cancer in a Population with Increased Prevalence of Triple-Negative Breast Cancer: Androgen Receptor and ALDH1 Expression in Ghanaian Women

BACKGROUND

The androgen receptor (AR) is a commonly-expressed hormone receptor in breast cancer and may be a marker of response to targeted anti-androgen therapy, a particularly attractive option for triple-negative breast cancer (TNBC). Gene expression studies suggest that ARs may distinguish a luminal/AR TNBC subtype from stem cell-like subtypes. TNBC frequency is two to three times higher in African American and African breast cancers compared with White American and European breast cancers, yet little is known regarding TNBC subtypes in high-frequency African-ancestry populations. We evaluated ARs and the mammary stem cell marker aldehyde dehydrogenase 1 (ALDH1) among breast cancers from Ghana, Africa.

METHODS

Overall, 147 formalin-fixed, paraffin-embedded invasive breast cancers from the Komfo Anoyke Teaching Hospital in Ghana were studied at the University of Michigan, and analyzed immunohistochemically for estrogen receptor (ER), progesterone receptor (PR), HER2/neu, ALDH1, and AR expression.

RESULTS

The median age of patients was 45 years. Only 31 cases (21 %) were ER-positive, and 14 (10 %) were HER2-positive; 89 (61 %) were TNBCs. For the entire group, 44 % were AR-positive and 45 % were ALDH1-positive. ER/PR-positive tumors were more likely to be AR-positive compared with ER/PR-negative tumors (87 vs. 26 %; p < 0.0001), but there was no association between ALDH1 and AR expression. Among the TNBC cases, 45 % were ALDH1-positive and 24 % were AR-positive. ALDH1 positivity was associated with AR positivity within the subset of TNBC (36 vs. 14 %; p = 0.019).

CONCLUSION

We confirmed other studies showing a high frequency of TNBC in Africa. Surprisingly, ALDH1 was found to correlate with AR expression among TNBC, suggesting that novel TNBC subtypes may exist among populations with African ancestry.

Abstract C11: Impact of pathologic specimen quality on classifying molecular subtypes of breast cancer: A pilot study from three hospitals in Ghana, Africa

Background: Breast cancer is a heterogeneous disease with clinically, molecularly and pathologically defined subtypes that have different etiologies, clinical presentations and outcomes. African women reportedly have especially high rates of breast cancers that are estrogen receptor (ER) or progesterone receptor (PR) negative, or triple negative [ER, PR and human epidermal growth factor receptor-2 (HER-2) negative], with the proportion reported for triple negative breast cancers ranging from 28-82%, compared to 11-20% among Caucasian populations. However, it is unclear to what extent pathology and specimen handling affect receptor measurements in Africa. Here we sought to determine pathology specimen quality of breast tumor tissues from three hospitals in Ghana where we are conducting a molecular epidemiologic study of breast cancer.

Methods: We acquired 15 formalin-fixed paraffin-embedded (FFPE) archived breast cancer tissue blocks with specimens obtained at biopsy (N=5) or surgery (N=10) from three hospitals in Ghana. Blocks were re-embedded and four 0.5um whole sections were cut for hematoxylin and eosin stains, and immunohistochemistry (IHC) using previously validated protocols for ER (clone 1D5), PR (clone PgR1294) and HER2 (polyclonal), all obtained from Dako (Carpinteria CA). Specimens were considered ER or PR positive if 10% or more cells stained positive, while HER2 was considered positive if intensity of staining was 3+.

Results: Specimens were noted to be embedded in high-melting temperature paraffin. To perform ER, PR, and HER2 IHC staining, deparaffinization procedures were optimized for hard paraffin. Zonal and gradient staining patterns were noted in surgical specimens, features that are likely due to delayed/prolonged fixation. Zonal/gradient staining issues were not identified in the needle biopsies, which were smaller compared to specimens collected at surgery and generally placed in buffered formalin immediately after collection. IHC assays of the tumor specimens revealed that 67% were ER-positive, 20% PR-positive, and 66% HER2 positive. The proportion negative for all three markers was 13%.

Conclusion: In contrast to previous reports for African breast cancer patients, within our sample of FFPE breast cancers from Ghana we found a higher prevalence of ER positive tumors and a lower prevalence of tumors negative for all three markers. These results suggest that the high rates of hormone receptor negativity previously reported in African populations may be inaccurate due to various sources of error, particularly fixation time and IHC staining protocols. Future studies focusing on proper documentation of sample collection procedures and optimization of IHC methods are required to determine the true prevalence of molecular subtypes of breast cancer among African women. Such efforts are essential for breast cancer surveillance, identifying etiologic factors for prevention efforts and developing more effective treatment programs.

Citation Format: Jonine D. Figueroa, Lawrence Edusei, Ernest Adjei, Nicholas Titiloye, Kris Ylaya, Beatrice Addai, Joe Nat Clegg-Lamptey, Baffour Awuah, Kofi Nyarko, Daniel Ansong, Seth Wiafe, Louise A. Brinton, Stephen Hewitt. Impact of pathologic specimen quality on classifying molecular subtypes of breast cancer: A pilot study from three hospitals in Ghana, Africa. [abstract]. In: Proceedings of the Sixth AACR Conference: The Science of Cancer Health Disparities; Dec 6–9, 2013; Atlanta, GA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2014;23(11 Suppl):Abstract nr C11. doi:10.1158/1538-7755.DISP13-C11

Characterizing breast cancer treatment pathways in Kumasi, Ghana from onset of symptoms to final outcome: outlook towards cancer control

BACKGROUND

Cancer rates are increasing in Africa, including Ghana. Breast cancer is the second most common cancer in incidence and mortality in Ghana.

OBJECTIVE

We outlined both breast cancer patient characteristics and management at the Komfo Anokye Teaching Hospital (KATH), the main cancer management hospital in central Ghana. Moreover, we identified the treatment interventions predictive of patient outcome.

METHODS

Medical records of 597 breast cancer patients seen in 2008-2011 were abstracted to investigate management and treatment patterns. Abstracted variables included type and extent of surgery, number and cycles of chemotherapy and radiotherapy, as well as the course of treatment completed.

RESULTS

Late stage at diagnosis was common, treatment plans of the study hospital were relatively standardized according to disease severity, and defaulting/interrupting treatment in the records was also common. Patients diagnosed with late stage cancer who received adjuvant therapy and patients with hormone status evaluation were more likely to have complied with treatment guidelines and continued oncotherapy at the study hospital than those who never had hormone status requested or reported.

CONCLUSIONS

Our study lends support to improving patient outcomes in low- and middle-income countries through raising knowledge and reporting of tumor hormonal status and providing appropriately tailored treatment. Achieving improved outcomes should also consider enhancing public understanding of the importance of early detection and completion of treatment.

Establishing effective registration systems in resource-limited settings: cancer registration in Kumasi, Ghana

Cancer control programs are needed worldwide to combat the increases in cancer incidence and mortality predicted for sub-Saharan Africa in the next decades. The effective design, implementation, and evaluation of such programs require population-based cancer registries. Ghana's second largest medical center, the Komfo Anokye Teaching Hospital (KATH) in Kumasi, has made initial progress at developing a cancer registry. This registry, however, is housed in the medical oncology/radiotherapy center at KATH and does not currently include data from other departments that also interact with cancer patients. The aim of this study was to improve KATH cancer registration by compiling cancer data from other major departments that see cancer patients. Using recent population estimates, we calculated crude cancer incidence rates of the "minimally-reported cases" for the Ashanti region. The most common cancers found in this study were breast (12.6 per 100,000), cervix (9.2 per 100,000), and prostate (8.8 per 100,000). These cancers occur at similar crude incidence rates in other West African countries. Females had overall higher incidence rates than males, which is consistent throughout the West African region. This study identified a number of methodological challenges facing cancer registries in Ghana that can be addressed to improve the quality of cancer registries in other resource-limited settings. Such registries should be tailored to the local health system context. A lack of coordination among the sources reporting cancer cases and a lack of understanding of local health-care systems and payment plans may interfere with the quality, completeness, and comparability of data from cancer registries in resource-limited settings. Steps, barriers, and solutions for improving cancer registration in Ghana and countries at similar levels are discussed.

Expression of aldehyde dehydrogenase 1 as a marker of mammary stem cells in benign and malignant breast lesions of Ghanaian women

BACKGROUND

Breast cancers that are negative for the estrogen receptor (ER), the progesterone receptor (PR), and the HER2 (human epidermal growth factor receptor 2) marker are more prevalent among African women, and the biologically aggressive nature of these triple-negative breast cancers (TNBCs) may be attributed to their mammary stem cell features. Little is known about expression of the mammary stem cell marker aldehyde dehydrogenase 1 (ALDH1) in African women. Novel data are reported regarding ALDH1 expression in benign and cancerous breast tissue of Ghanaian women.

METHODS

Formalin-fixed, paraffin-embedded specimens were transported from the Komfo Anoyke Teaching Hospital in Kumasi, Ghana to the University of Michigan for centralized histopathology study. Expression of ER, PR, HER2, and ALDH1 was assessed by immunohistochemistry. ALDH1 staining was further characterized by its presence in stromal versus epithelial and/or tumor components of tissue.

RESULTS

A total of 173 women contributed to this study: 69 with benign breast conditions, mean age 24 years, and 104 with breast cancer, mean age 49 years. The proportion of benign breast conditions expressing stromal ALDH1 (n = 40, 58%) was significantly higher than those with cancer (n = 44, 42.3%) (P = .043). Among the cancers, TNBC had the highest prevalence of ALDH1 expression, either in stroma or in epithelial cells. More than 2-fold higher likelihood of ALDH1 expression was observed in TNBC cases compared with other breast cancer subtypes (odds ratio = 2.38, 95% confidence interval 1.03-5.52, P = .042).

CONCLUSIONS

ALDH1 expression was higher in stromal components of benign compared with cancerous lesions. Of the ER-, PR-, and HER2-defined subtypes of breast cancer, expression of ALDH1 was highest in TNBC.

Breast cancer in Kumasi, Ghana

BACKGROUND

Breast cancer is the leading cause of cancer deaths in Ghanaian women.

OBJECTIVE

To describes the characteristics of breast cancer patients attending the Komfo Anokye Teaching Hospital in Kumasi, Ghana.

METHOD

The study was conducted at the Komfo Anokye Teaching Hospital. Between July 1st 2004 and June 30(th) 2009 patients presenting with breast lumps were assessed by clinical examination, imaging studies and pathological examination. Relevant clinical and pathological were recorded prospectively data on all patients with microscopically proven breast cancer. The cancers were graded according to the modified Bloom-Richardson system. Tissue immunoperoxidase stains for oestrogen, progesterone receptors and c-erb2 oncogene were performed with commercially prepared antigens and reagents.

RESULTS

Nineteen thousand four hundred and twenty-three (19,423) patients were seen during the study period. There were 330 (1.7%) patients with histologically proven breast cancer. The mean age was 49.1 years. A palpable breast lump was detected in 248 patients (75.2%). Two hundred and eighty-one patients (85.2%) presented with Stages III and IV, 271 (82.1%) invasive and 230 (85.2%) high grade carcinomas. Oestrogen and progesterone receptors were positive in 32 and 9 cases respectively. Her2 protein was positive in 11 cases.

CONCLUSION

In Kumasi, as in other parts of Ghana, breast cancer affects mostly young pre-menopausal who present with advanced disease. The cancers have unfavourable prognostic features and are unlikely to respond to hormonal therapy.

A giant guteal schwannoma with extension into the pelvis: a case report

BACKGROUND

Schwannomas are uncommon slow growing tumours arising from the nerve sheath or Schwann cell.

OBJECTIVE

To report a case and the surgical removal of a giant complex schwannoma and to highlight the value of extensive investigations including a preoperative histologic diagnosis in the successful surgical management of uncommon large benign tumours.

METHODS

A 39-year-old man presented with a 15-year history of a large mass in the right gluteal region. He was clinically evaluated, subjected to imaging studies and surgery.

RESULTS

Clinical examination revealed a 40 cm by 60 cm mass in the right gluteal region and continuous with a 25 cm by 15 cm pelvic mass. The ultrasound scan revealed a very complex (mixed solid and fluid containing) gluteal mass with extension to the pelvis. The CT scan showed a very large, well defined lobulated tumour with cystic spaces and enhancing nodules. The tumour extended through the ischiadic foramen into the pelvis and posteriorly into the thigh muscles. A Doppler scan of the pelvic vessels revealed that the right common and internal iliac arteries were both compressed but not occluded. An incisional biopsy was reported as a Schwannoma with xanthomatous changes and an immuno histochemistry profile of S-100+, Ki-67+ (less than 1% of the cells). A right foot drop following the surgery responded to physiotherapy. The duration of total hospital stay was 12 weeks.

CONCLUSION

The staged excision of large and complex schwannomas is safe. It is essential that a preoperative histological diagnosis is made to establish that the tumor is truly benign.