BackgroundData on cancers is a challenge in most developing countries. Population-based cancer registries are also not common in developing countries despite the usefulness of such registries in informing cancer prevention and control programmes. The availability of population-based data on cancers in Africa varies across different countries. In Ghana, data and research on cancer have focussed on specific cancers and have been hospital-based with no reference population. The Kumasi Cancer Registry was established as the first population-based cancer registry in Ghana in 2012 to provide information on cancer cases seen in the city of Kumasi.MethodsThis paper reviews data from the Kumasi Cancer Registry for the year 2012. The reference geographic area for the registry is the city of Kumasi as designated by the 2010 Ghana Population and Housing Census. Data was from all clinical departments of the Komfo Anokye Teaching Hospital, Pathology Laboratory Results, Death Certificates and the Kumasi South Regional Hospital. Data was abstracted and entered into Canreg 5 database. Analysis was conducted using Canreg 5, Microsoft Excel and Epi Info Version 7.1.2.0.ResultsThe majority of cancers were recorded among females accounting for 69.6% of all cases. The mean age at diagnosis for all cases was 51.6 years. Among males, the mean age at diagnosis was 48.4 compared with 53.0 years for females. The commonest cancers among males were cancers of the Liver (21.1%), Prostate (13.2%), Lung (5.3%) and Stomach (5.3%). Among females, the commonest cancers were cancers of the Breast (33.9%), Cervix (29.4%), Ovary (11.3%) and Endometrium (4.5%). Histology of the primary tumour was the basis of diagnosis in 74% of cases with clinical and other investigations accounting for 17% and 9% respectively. The estimated cancer incidence Age Adjusted Standardised Rate for males was 10.9/100,000 and 22.4/100, 000 for females.ConclusionThis first attempt at population-based cancer registration in Ghana indicates that such registries are feasible in resource limited settings as ours. Strengthening Public Health Surveillance and establishing more Population-based Cancer Registries will help improve data quality and national efforts at cancer prevention and control in Ghana.

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.

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.

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 (OR) 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 (82-99%) of interviewed subjects providing blood and saliva samples; lower proportions (46-58%) provided fecal samples. While risk factor prevalences were quite 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, 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.

Women of sub-Saharan African descent have disproportionately higher incidence of Triple Negative Breast Cancer (TNBC), and TNBC-specific mortality. Population comparative studies show racial differences in TNBC biology, including higher prevalence of basal-like and Quadruple-Negative subtypes in African Americans (AA). However, previous investigations relied on self-reported race (SRR) of primarily United States (US) populations. Due to heterogenous genetic admixture, and biological consequences of social determinants, the true association of African ancestry with TNBC biology is unclear. To address this, we conducted RNAseq on an international cohort of AAs, west and east Africans with TNBC. Using comprehensive genetic ancestry estimation in this African-enriched cohort, we found expression of 613 genes associated with African ancestry and 2000+ associated with regional African ancestry. A subset of African-associated genes also showed differences in normal breast tissue. Pathway enrichment and deconvolution of tumor cellular composition revealed tumor-associated immunological profiles are distinct in patients of African descent.

PurposeBreast cancer, the most common cancer worldwide, is the leading cause of cancer mortality in Ghanaian women. Previous studies find Ghanaian women are diagnosed at a younger age and at more advanced stages (III and IV), and have tumors with characteristics similar to African American women. We sought to remedy gaps in knowledge about breast cancer survival in Ghana and its relation to demographic and biologic factors of the tumors at diagnosis to assist in cancer control and registration planning.MethodsIndividuals with a breast cancer diagnosis who sought care at Komfo Anokye Teaching Hospital from 2009 to 2014 were identified via medical records. Follow-up telephone interviews were held to assess survival. Kaplan-Meier plots and Cox proportional hazards models assessed survival associated with clinical and demographic characteristics.ResultsA total of 223 patients completed follow-up and were analyzed. The median survival was 3.8 years. Approximately 50% of patients were diagnosed with grade 3 tumors, which significantly increased the risk of recurrence or death (hazard ratio [HR] for grade 2 versus 1, 2.98; 95% CI, 1.26 to 7.02; HR grade 3 v 1, 2.56; 95% CI, 1.08 to 6.07; P = .04). No other variables were significantly associated with survival.ConclusionHigher tumor grade was significantly associated with shorter survival, indicating impact of aggressive biology at diagnosis on higher risk of cancer spread and recurrence. Contrary to prevailing notions, telephone numbers were not reliable for follow-up. Collecting additional contact information will likely contribute to improvements in patient care and tracking. A region-wide population-based active registry is important to implement cancer control programs and improve survival in sub-Saharan Africa.

BackgroundSignificant clinical and research applications are driving large scale adoption of individualized tumor sequencing in cancer in order to identify tumors-specific mutations. When a matched germline sample is available, somatic mutations may be identified using comparative callers. However, matched germline samples are frequently not available such as with archival tissues, which makes it difficult to distinguish somatic from germline variants. While population databases may be used to filter out known germline variants, recent studies have shown private germline variants result in an inflated false positive rate in unmatched tumor samples, and the number germline false positives in an individual may be related to ancestry.MethodsFirst, we examined the relationship between the germline false positives and ancestry. Then we developed and implemented a tumor only caller (LumosVar) that leverages differences in allelic frequency between somatic and germline variants in impure tumors. We used simulated data to systematically examine how copy number alterations, tumor purity, and sequencing depth should affect the sensitivity of our caller. Finally, we evaluated the caller on real data.ResultsWe find the germline false-positive rate is significantly higher for individuals of non-European Ancestry largely due to the limited diversity in public polymorphism databases and due to population-specific characteristics such as admixture or recent expansions. Our Bayesian tumor only caller (LumosVar) is able to greatly reduce false positives from private germline variants, and our sensitivity is similar to predictions based on simulated data.ConclusionsTaken together, our results suggest that studies of individuals of non-European ancestry would most benefit from our approach. However, high sensitivity requires sufficiently impure tumors and adequate sequencing depth. Even in impure tumors, there are copy number alterations that result in germline and somatic variants having similar allele frequencies, limiting the sensitivity of the approach. We believe our approach could greatly improve the analysis of archival samples in a research setting where the normal is not available.Electronic supplementary materialThe online version of this article (10.1186/s12920-017-0296-8) contains supplementary material, which is available to authorized users.

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.