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.

The distribution of hrHPV genotypes among cervical cancer cases diagnosed across Ghana: a cross-sectional study.

BACKGROUND: The burden of cervical cancer in Ghana is high due to a lack of a national screening and vaccination program. Geographical variations in high-risk Human Papilloma Virus incidence and type should be considered for vaccine improvement and screening in LMICs. METHODS: A descriptive, multi-center cross-sectional study with purposive sampling of cases with cervical cancer diagnosed from January 2012 through to December 2018 was employed relying on archived Formalin Fixed Paraffin Embedded (FFPE) tissues from four (4) Teaching Hospitals. Cervical cancers were assessed for histopathological features following WHO guidelines. In addition, the novel Tumour Budding and Nest Size Grade (TBNS) for SCC, SILVA pattern of invasion for EAC and Tumour Infiltrating Lymphocytes (TILs) were assessed. High Risk HPV testing was performed using an isothermal, multiplex nucleic acid amplification method from ATILA biosystem (Mountain View California, USA). The FFPE blocks were tested for 15 hrHPV genotypes. Results were analyzed using SPSS v.26.0, with descriptive statistics and cross-tabulation and chi-square tests done with significance established at p < 0.05. RESULTS: A total of 297 cases were identified for the study with ages ranging from 20 to 95 years. The peak age group for cervical cancer was 46 to 55 years. For those tested, hrHPV positivity rate was 85.4% [EAC (84.6%) and SCC (85.6%)]. The top five hrHPV serotypes for both histological cancers were 59 (40.0%), 35 (32.0%), 18 (30.0%), 16 (15.0%), and 33 (10.0%) respectively. Approximately, 58.2% of infections were multiple. Single hrHPV infections were mostly caused by hrHPV 59 (28.9%), and 16 (26.3%). TBNS grade for SCC, SILVA pattern of invasion for EAC and TILs did not show any statistically significant relationship with hrHPV. CONCLUSION: We affirm reported differences in hrHPV types associated with cervical cancer in Ghana with hrHPV types such as 59, 35, and 33 forming a significant proportion of hrHPV types associated with cervical cancer. This difference in hrHPV types should guide vaccine improvement and triaging of hrHPV positives. Though multiple infections are more common, some hrHPV types such as hrHPV 16 and 59 are responsible for most single infections associated with cervical cancer. Simple haematoxylin and eosin-based morphological assessments can improve the prognostication of patients with cervical cancer.

Participant Evaluation of a Multi-disciplinary Oncology Preceptorship Training Program for Oncology Health Professionals from Kumasi, Ghana.

A critical shortage of skilled healthcare workers is a primary cause of disparate global cancer outcomes. We report participant evaluation of a multidisciplinary preceptorship program. In collaboration with the city of Kumasi, Ghana, Mayo Clinic and the City Cancer Challenge hosted a preceptorship program for comprehensive multidisciplinary breast and cervix cancer training. A total of 14 healthcare workers from Kumasi received two weeks of training at Mayo Clinic in November and December 2021. Each participant and preceptor were requested to complete an anonymous post-participation survey. Of the 14 trainee participants, 10 (71%) completed the survey. All respondents found the program "valuable and applicable to their clinical practice." Ninety percent reported they were able to "review effective and critical elements in the development and expansion of the multidisciplinary team" and able to "solve practical clinical cases as a team". General themes of satisfaction included: (1) organization and administration, (2) clinical observations and demonstrations, (3) guidelines development, and (4) recognizing the central importance of cultivating a team-based approach. Of the 40 preceptors, 16 (40%) completed the survey. All respondents reported they felt the training would meaningfully "influence patient care in Ghana", that participation "added value or joy to their clinical practice," and all wished to "participate in future preceptorship programs". After a focused two-week program, trainees reported high satisfaction, usefulness from observing specialized cancer care, and value in closely observing a multidisciplinary oncology team. Preceptors reported the experience added joy and perspective to their clinical practice and wished to participate in future programs.

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.

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.

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.

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.

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.

Hereditary Susceptibility for Triple Negative Breast Cancer Associated With Western Sub-Saharan African Ancestry: Results From an International Surgical Breast Cancer Collaborative.

OBJECTIVE: To investigate subtype-specific risk of germline alleles associated with triple negative breast cancer (TNBC) in African ancestry populations. BACKGROUND: Breast cancer (BC) mortality is higher in African American (AA) compared to White American (WA) women; this disparity is partly explained by 2-fold higher TNBC incidence. METHODS: We used a surgically maintained biospecimen cohort of 2884 BC cases. Subsets of the total (760 AA; 962 WA; 910 West African/Ghanaian; 252 East African/Ethiopian) were analyzed for genotypes of candidate alleles. A subset of 417 healthy controls were also genotyped, to measure associations with overall BC risk and TNBC. RESULTS: TNBC frequency was highest in Ghanaian and AA cases (49% and 44% respectively; P < 0.0001) and lowest in Ethiopian and WA cases (17% and 24% respectively; P < 0.0001). TNBC cases had higher West African ancestry than non-TNBC (P < 0.0001). Frequency of the Duffy-null allele (rs2814778; an African ancestral variant adopted under selective pressure as protection against malaria) was associated with TNBC-specific risk (P < 0.0001), quantified West African Ancestry (P < 0.0001) and was more common in AA, Ghanaians, and TNBC cases. Additionally, rs4849887 was significantly associated with overall BC risk, and both rs2363956 and rs13000023 were associated with TNBC-specific risk, although none as strongly as the Duffy-null variant. CONCLUSIONS: West African ancestry is strongly correlated with TNBC status, as well as germline variants related to BC risk. The Duffy-null allele was associated with TNBC risk in our cohort.

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.

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

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.

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

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

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.

Cervical cancer screening in Ghana, west Africa: prevalence of abnormal cytology and challenges for expanding screening.

Aims were to assess the prevalence of Papanicolaou (Pap) abnormalities found with cervical cancer screening in Agogo and Nkawie, communities in the Ashanti region of Ghana, and compare the correlation between Pap readings performed at the Komfo Anokye Teaching Hospital in Kumasi, Ghana, and at the Mayo Clinic cytology laboratory in Rochester, MN. Demographic data was collected and Pap tests were performed on women recruited for screening in the communities of Agogo (n=119) and Nkawie (n=255). The Pap tests were assessed by pathology laboratory staff at Komfo Anokye Teaching Hospital and Mayo Clinic. There was a significant difference in prevalence of abnormal cytology between the sites with a rate of 12.6% in Agogo and 3.5% in Nkawie (P=0.016). Demographic differences were noted in education level (P<0.001), occupation (P<0.001), religion (P=0.002), and marital status (P<0.001). The Cohen correlation coefficient between the two pathology departments interpreting samples was 0.185, which indicates a significant degree of discordance (P<0.001). Currently Ghana does not have a national cervical cancer screening program. Identifying higher risk communities and patients as a priority for screening may be useful with limited resources. Accurate identification of Pap abnormalities is necessary to implement an effective screening program.

Hormone receptors and Her2 expression in breast cancer in sub-Saharan Africa. A comparative study of biopsies from Ghana and Norway.

Hormonal treatment of breast cancer is effective only in patients whose tumors express estrogen and/or progesterone receptors (ER, PR). Receptor assessment is often not available in low-resource areas, and the choice may be to apply endocrine therapy to all or none of breast cancer patients, depending on the proportion of patients that can be expected to respond. Fifty-one invasive breast cancers from Ghana and 100 from Norway diagnosed in the same laboratory during the same time period were reexamined in a blinded slide review. Of Ghanaian tumors, 76% were ER+ (≥1% ER+ tumor cells). Of Norwegian tumors, 85% were ER+. Triple-negative tumors were seen in 22% of Ghanaian patients and in 7% of Norwegian patients. A review of previous similar studies in sub-Saharan patients shows very discrepant results. Standardization and quality control of receptor assessment and well-designed clinical trials in sub-Saharan African breast cancer patients are needed to give a sound basis for endocrine treatment in this area.

Contribution of pre-diagnostic host factors to shaping the stromal microenvironment of breast cancer among sub-Saharan African women.

BACKGROUND: The stromal microenvironment (SME) is integral to breast cancer (BC) biology, impacting metastatic proclivity and treatment response. Emerging data indicate that host factors may impact the SME, but the relationship between pre-diagnostic host factors and SME phenotype remains poorly characterized, particularly among women of African ancestry. METHODS: We conducted a case-only analysis involving 792 BC patients (17-84 years) from the Ghana Breast Health Study (GBHS). High-accuracy machine-learning algorithms were applied to standard H&E-stained images to characterize SME phenotypes (including percent tumor-associated connective tissue stroma, Ta-CTS (%), and tumor-associated stromal cellular density, Ta-SCD (%)). Associations between pre-diagnostic host factors and SME phenotypes were assessed in multivariable linear regression models. RESULTS: Decreasing Ta-CTS and increasing Ta-SCD were associated with aggressive, mostly high-grade tumors (p-value<0.001). Several pre-diagnostic host factors were associated with Ta-SCD independently of tumor characteristics. Compared with nulliparous women, parous women had higher levels of Ta-SCD [mean (standard deviation, SD) = 31.3% (7.6%) vs. 28.9% (7.1%); p-value=0.01]. Similarly, women with a positive family history of breast cancer had higher levels of Ta-SCD than those without family history [mean (SD) = 33.0% (7.5%)] vs. 30.9% (7.6%); p-value=0.03]. Conversely, increasing body size was associated with decreasing Ta-SCD [mean (SD) = 32.0% (7.4%), 31.3% (7.3%), and 29.0% (8.0%) for slight, average, and large body sizes, respectively, p-value=0.005]. CONCLUSIONS: Epidemiological risk factors were associated with varying degrees of stromal cellularity in tumors, independently of clinicopathological characteristics. IMPACT: The findings raise the possibility that epidemiological risk factors may partly influence tumor biology via the SME.

Patient-derived tumor organoids with p53 mutations, and not wild-type p53, are sensitive to synergistic combination PARP inhibitor treatment.

Poly (ADP-ribose) polymerase inhibitors (PARPi) are used for patients with BRCA1/2 mutations, but patients with other mutations may benefit from PARPi treatment. Another mutation that is present in more cancers than BRCA1/2 is mutation to the TP53 gene. In 2D breast cancer cell lines, mutant p53 (mtp53) proteins tightly associate with replicating DNA and Poly (ADP-ribose) polymerase (PARP) protein. Combination drug treatment with the alkylating agent temozolomide and the PARPi talazoparib kills mtp53 expressing 2D grown breast cancer cell lines. We evaluated the sensitivity to the combination of temozolomide plus PARPi talazoparib treatment to breast and lung cancer patient-derived tumor organoids (PDTOs). The combination of the two drugs was synergistic for a cytotoxic response in PDTOs with mtp53 but not for PDTOs with wtp53. The combination of talazoparib and temozolomide induced more DNA double-strand breaks in mtp53 expressing organoids than in wild-type p53 expressing organoids as shown by increased γ-H2AX protein expression. Moreover, breast cancer tissue microarrays (TMAs) showed a positive correlation between stable p53 and high PARP1 expression in sub-groups of breast cancers, which may indicate sub-classes of breast cancers sensitive to PARPi therapy. These results suggest that mtp53 could be a biomarker to predict response to the combination of PARPi talazoparib-temozolomide treatment.