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BACKGROUND: Native African men (NAM) experience a disproportionate burden of prostate cancer (PCa) and have higher mortality rates compared to European American men (EAM). While socioeconomic status has been implicated as a driver of this disparity, little is known about the genomic mechanisms and distinct biological pathways that are associated with PCa of native men of African origin. METHODS: To understand biological factors that contribute to this disparity we utilized a total of 406 multi-institutional localized PCa samples, collected by Men of African Descent and Carcinoma of the Prostate biospecimen network and Moffitt Cancer Center/University of Pennsylvania Health science system. We performed comparative genomics and immunohistochemistry to identify the biomarkers that are highly enriched in NAM from west Africa and compared them with African American Men (AAM) and EAM. Quantified messenger RNA expression and Median H scores based on immune reactivity of staining cells, were compared using Mann Whitney test. For gene expression analysis, p values were further adjusted for multiple comparisons using false discovery rates. RESULTS: Immunohistochemical analysis on selected biomarkers showed a consistent association between ETS related gene (ERG) status and race with 83% of NAM exhibiting tumors that lacked TMPRSS2-ERG translocation (ERGnegative ) as compared to AAM (71%) and EAM (52%). A higher proportion of NAM (29%) were also found to be double negative (ERGnegative and PTENLoss ) as compared to AAM (6%) and EAM (7%). NAM tumors had significantly higher immunoreactivity (H-score) for PSMA, and EZH2, whereas they have lower H-score for PTEN, MYC, AR, RB and Racemase, (all p < .05). Comparative genomics revealed that NAM had significant transcriptomic variability in AR-activity score. In pathways enrichment analysis NAM tumors exhibited the enrichment of proinflammatory pathways including cytokine, interleukins, inflammatory response, and nuclear factor kappa B signaling. CONCLUSIONS: Prostate tumors in NAM are genomically distinct and are characterized by the dysregulation of several biomarkers. Furthermore, these tumors are also highly enriched for the major proinflammatory pathways. These distinct biological features may have implications for diagnosis and response to targeted therapy among Black men, globally.
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Carcinoma , Canais de Potássio Éter-A-Go-Go/genética , Neoplasias da Próstata , Serina Endopeptidases/genética , Bancos de Espécimes Biológicos , População Negra , Carcinoma/etnologia , Carcinoma/genética , Carcinoma/patologia , Perfilação da Expressão Gênica/métodos , Perfilação da Expressão Gênica/estatística & dados numéricos , Testes Genéticos/métodos , Genômica , Gana/epidemiologia , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Neoplasias da Próstata/etnologia , Neoplasias da Próstata/genética , Neoplasias da Próstata/patologia , Senegal/epidemiologia , Transdução de Sinais/genética , Estados Unidos/etnologia , População BrancaRESUMO
BACKGROUND: Between 2005 and 2014, Ghana's Wilms tumor (WT) 2-year disease-free survival of 44% trailed behind that of high-income countries. This study aimed to uncover social determinants of health leading to preventable WT death in Ghana. METHODS: WT patient records (2014-2022) at Korle-Bu Teaching Hospital (KBTH; Ghana) were reviewed retrospectively. Demographics, clinical course, tumor characteristics, and survival were evaluated using t-tests, Pearson Chi-square, and multivariate Cox logistic regression. RESULTS: Of 127 patients identified, 65 were female. Median age was 44 months [IQR 25-66]. Forty-eight patients (38%) presented with distant metastasis (75% lung, 25% liver), which associated with hypoalbuminemia (p = 0.009), caregiver informal employment (p = 0.04), and larger tumors (p = 0.002). Despite neoadjuvant chemotherapy shrinking 84% of tumors, larger initial size associated with incomplete resection (p = 0.046). Of 110 nephrectomies, 31 patients had residual disease, negatively impacting survival (p = 2.7 × 10-5). Twenty-two patients (17%) abandoned treatment (45% before nephrectomy; 55% after nephrectomy), with seven patients ultimately lost to follow-up (LTFU). Decedents represented 43% of stage IV patients compared to 28% in other stages. Event-free survival (EFS) was 60% at 4 years with overall survival (OS) at 67%. CONCLUSIONS: Although Ghana's WT survival has improved, informal employment and distance from KBTH predisposed patients to delayed referral, greater tumor burden, hypoalbuminemia, and lower survival. TYPE OF STUDY: Prognosis Study. LEVEL OF EVIDENCE: II.
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Neoplasias Renais , Nefrectomia , Tumor de Wilms , Humanos , Tumor de Wilms/terapia , Tumor de Wilms/mortalidade , Tumor de Wilms/patologia , Tumor de Wilms/cirurgia , Gana/epidemiologia , Feminino , Masculino , Estudos Retrospectivos , Pré-Escolar , Neoplasias Renais/terapia , Neoplasias Renais/patologia , Neoplasias Renais/mortalidade , Neoplasias Renais/cirurgia , Carga Tumoral , Lactente , Criança , Intervalo Livre de Doença , Determinantes Sociais da Saúde , Terapia Neoadjuvante/estatística & dados numéricosRESUMO
INTRODUCTION: Breast cancer poses a significant health challenge in Sub-Saharan Africa, particularly in Ghana, where late-stage diagnoses and limited healthcare access contribute to elevated mortality rates. This study focuses on the crucial role of pathology and laboratory medical (PALM) services in the timely diagnosis of breast cancer within Ghana. METHODS: A cross-sectional survey of hospitals was completed from November 2020 to October 2021, with 94.8% of identified in-country hospitals participating. Pathology service-related parameters assessed included whether pathology was available for the diagnosis of breast cancer on-site or via external referral, the number of pathology personnel, additional breast cancer diagnostic capabilities including estrogen and progesterone and/or HER2 testing, and the time from biopsy to patients receiving their results. Geospatial mapping was used to identify areas of limited access. RESULTS: Of the 328 participating hospitals, 136 (41%) reported breast cancer pathology services, with only 6 having on-site capabilities. Pathology personnel, comprising 15 consultants and 15 specialists, were concentrated in major referral centers, particularly in Greater Accra and Kumasi. An assessment of referral patterns suggested that 75% of the population reside within an hour of breast cancer pathology services. Among the 136 hospitals with access to breast cancer pathology, only a limited number reported that results included ER/PR (38%) and HER2 testing (33%). CONCLUSION: Ghana has been able to ensure significant pathology service availability through robust referral pathways with centralized labs. Despite this, difficulties persist with the majority of pathology results not including hormone receptor testing which is important in providing tumor specific treatment.
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Neoplasias da Mama , Acessibilidade aos Serviços de Saúde , Humanos , Gana/epidemiologia , Neoplasias da Mama/patologia , Neoplasias da Mama/epidemiologia , Neoplasias da Mama/diagnóstico , Feminino , Acessibilidade aos Serviços de Saúde/estatística & dados numéricos , Estudos Transversais , Encaminhamento e Consulta/estatística & dados numéricosRESUMO
Background: Non-Hodgkin lymphomas (NHLs) are a heterogeneous group of clonal lymphoid tumours originating from lymphocytes. They constitute about 90% of an estimated 3%-4% worldwide distribution of malignant lymphomas among various cancers. Despite the continuous rise and associated deaths, research on NHLs, and in particular the area of immunophenotypic spectrum is limited in Ghana and sub-Saharan Africa. Methods: A retrospective, descriptive study in which archived tissue blocks of histologically diagnosed NHLs at a tertiary hospital in Accra, Ghana, were used. Antigenic phenotypes were determined by immunohistochemistry. Results: A total of 66 cases of NHLs, with a mean age of 50.2 ± 16.1 years, were selected for the study. Among the targeted markers, cluster of differentiation 20 (CD20) was the most commonly expressed in 89.4% (59) cases. Immunohistochemistry studies revealed a greater proportion of B cell lymphomas of 89.4%. Five subtypes were successfully identified, of which diffuse large B cell lymphoma constitutes the predominant group (40.9%). A significant association was observed between phenotypic cell types and outcomes of NHLs (p = 0.011). Conclusion: Adult NHLs were mostly due to the malignant transformation of B cells with diffuse large B cell lymphoma being the commonest subtype. The present study therefore serves as preliminary data for further research towards the adoption of an improved treatment regimen and management of NHLs.
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BACKGROUND: Genome-wide association studies do not always replicate well across populations, limiting the generalizability of polygenic risk scores (PRS). Despite higher incidence and mortality rates of prostate cancer in men of African descent, much of what is known about cancer genetics comes from populations of European descent. To understand how well genetic predictions perform in different populations, we evaluated test characteristics of PRS from three previous studies using data from the UK Biobank and a novel dataset of 1298 prostate cancer cases and 1333 controls from Ghana, Nigeria, Senegal, and South Africa. RESULTS: Allele frequency differences cause predicted risks of prostate cancer to vary across populations. However, natural selection is not the primary driver of these differences. Comparing continental datasets, we find that polygenic predictions of case vs. control status are more effective for European individuals (AUC 0.608-0.707, OR 2.37-5.71) than for African individuals (AUC 0.502-0.585, OR 0.95-2.01). Furthermore, PRS that leverage information from African Americans yield modest AUC and odds ratio improvements for sub-Saharan African individuals. These improvements were larger for West Africans than for South Africans. Finally, we find that existing PRS are largely unable to predict whether African individuals develop aggressive forms of prostate cancer, as specified by higher tumor stages or Gleason scores. CONCLUSIONS: Genetic predictions of prostate cancer perform poorly if the study sample does not match the ancestry of the original GWAS. PRS built from European GWAS may be inadequate for application in non-European populations and perpetuate existing health disparities.
Assuntos
Estudo de Associação Genômica Ampla , Neoplasias da Próstata , África Subsaariana/epidemiologia , Predisposição Genética para Doença , Humanos , Masculino , Neoplasias da Próstata/genética , Fatores de RiscoRESUMO
Although prostate cancer is the leading cause of cancer mortality for African men, the vast majority of known disease associations have been detected in European study cohorts. Furthermore, most genome-wide association studies have used genotyping arrays that are hindered by SNP ascertainment bias. To overcome these disparities in genomic medicine, the Men of African Descent and Carcinoma of the Prostate (MADCaP) Network has developed a genotyping array that is optimized for African populations. The MADCaP Array contains more than 1.5 million markers and an imputation backbone that successfully tags over 94% of common genetic variants in African populations. This array also has a high density of markers in genomic regions associated with cancer susceptibility, including 8q24. We assessed the effectiveness of the MADCaP Array by genotyping 399 prostate cancer cases and 403 controls from seven urban study sites in sub-Saharan Africa. Samples from Ghana and Nigeria clustered together, whereas samples from Senegal and South Africa yielded distinct ancestry clusters. Using the MADCaP array, we identified cancer-associated loci that have large allele frequency differences across African populations. Polygenic risk scores for prostate cancer were higher in Nigeria than in Senegal. In summary, individual and population-level differences in prostate cancer risk were revealed using a novel genotyping array. SIGNIFICANCE: This study presents an Africa-specific genotyping array, which enables investigators to identify novel disease associations and to fine-map genetic loci that are associated with prostate and other cancers.