Cancer in the Sudan: an overview of the current status of knowledge on tumor patterns and risk factors

Acetylcholinesterase enzyme among cancer patients a potential diagnostic and prognostic indicator a multicenter case-control study

Acetylcholinesterase enzyme (AChE) activity is impaired by a variety of inhibitors including organophosphorus pesticides, leading to the accumulation of acetylcholine. In this study, we aimed to determine the association between cancer and the blood level of the (AChE). This is a multicenter hospital-based case-control study conducted in the Radiation and Isotopes Center Khartoum, and Institute of Nuclear Medicine and Molecular Biology and Oncology Gezira. One hundred and fifty participants, half of them cancer patients and half cancer free were recruited. All participants were screened for demographic, environmental, occupational, and clinical characteristics. Blood for the (AChE) activity test was drawn from participants in the two groups. The mean age of the participants was 40.6 ± 14.8 years. Geographical distribution showed the Central Region of Sudan had the highest rate of cancer, followed by North State, Khartoum State, West State, and East State. The most common tumor subtype was breast cancer, followed by leukemia, colon, esophageal, and prostate cancer. Inferential analysis revealed significantly impaired (AChE) activity among cancer patients compared to controls (53.4 ± 20.3% vs. 93.8 ± 8.8, p-value 0.001). There was a significant statistical association between impaired (AChE) activity and cancer. (AChE) activity might be applied in the future as a diagnostic biomarker and therapeutic target. Further large sample and molecular studies are recommended.

Clinical pathological characteristics and treatment outcomes of renal cell carcinoma (RCC): a retrospective study from Sudan

Background

Worldwide, renal cell carcinoma comprises 2.2% and 1.8% of global cancer incidence and mortality, respectively. Studies of epidemiology, treatment modalities and outcomes of renal cell carcinoma (RCC) in Sudan are scarce. To address this shortcoming, we evaluated baseline information on the epidemiology, types of treatment and outcomes of RCC at Gezira Hospital for Renal Diseases and Surgery (GHRDS) and the National Cancer Institute (NCI).

Methods

We performed a retrospective, descriptive study of all patients with RCC, who were treated in GHRDS and NCI from January 2000 to December 2015.

Results

A total of 189 patients with RCC were identified over the study period. Tumours were more common among male patients (56%) and involved the left kidney in 52% of cases. The median age at diagnosis was 57 years (range: 21-90 years). Loin pain was the most frequent symptom (n = 103 patients) followed by weight loss (n = 103 patients) and haematuria (n = 65 patients). The most common histopathologic type of RCC was clear cell (73.5%), followed by papillary (13.8%) and chromophobe (1.6%). The relative frequencies of stages I-IV were 3.2%, 14.3%, 29.1% and 53.4%, respectively. The overall median survival rate was 24 months, and the 5-year survival rate was 40%. The 5-year survival rate in stages I-IV was 95%, 83%, 39%, and 17%, respectively. Advanced stages and higher-grade tumour were associated with worse survival. The median survival of stage IV patients was better for patients who underwent nephrectomy (11.0 months) compared to those who did not undergo nephrectomy (4.0 months) (p value = 0.28).

Conclusion

Our findings reveal poor outcomes for patients with RCC in Sudan, which is most likely due to the high proportion of patients presenting with advanced stages at the time of initial presentation.

Simultaneous Multiplexed Quantification of Banned Sudan Dyes Using Surface Enhanced Raman Scattering and Chemometrics

Azo compounds such as the Sudan dyes I-IV are frequently used illegally as colorants and added to a wide range of foods. These compounds have been linked to a number of food safety hazards. Several methods have been proposed to detect food contamination by azo compounds and most of these are laboratory based; however, the development of reliable and portable methods for the detection and quantification of food contaminated by these chemicals in low concentration is still needed due to their potentially carcinogenic properties. In this study, we investigated the ability of surface enhanced Raman scattering (SERS) combined with chemometrics to quantify Sudan I-IV dyes. SERS spectra were acquired using a portable Raman device and gold nanoparticles were employed as the SERS substrate. As these dyes are hydrophobic, they were first dissolved in water: acetonitrile (1:10, v/v) as single Sudan dyes (I-IV) at varying concentrations. SERS was performed at 785 nm and the spectra were analyzed by using partial least squares regression (PLS-R) with double cross-validations. The coefficient of determination (Q²) were 0.9286, 0.9206, 0.8676 and 0.9705 for Sudan I to IV, respectively; the corresponding limits of detection (LOD) for these dyes were estimated to be 6.27 × 10^-6, 5.35 × 10^-5, 9.40 × 10^-6 and 1.84 × 10^-6 M. Next, quadruplex mixtures were made containing all four Sudan dyes. As the number of possible combinations needed to cover the full concentration range at 5% intervals would have meant collecting SERS spectra from 194,481 samples (21⁴ combinations) we used a sustainable solution based on Latin hypercubic sampling and reduced the number of mixtures to be analyzed to just 90. After collecting SERS spectra from these mixture PLS-R models with bootstrapping validations were employed. The results were slightly worse in which the Q² for Sudan I to IV were 0.8593, 0.7255, 0.5207 and 0.5940 when PLS1 models (i.e., one model for one dye) was employed and they changed to 0.8329, 0.7288, 0.5032 and 0.5459 when PLS2 models were employed (i.e., four dyes were modelled simultaneously). These results showed the potential of SERS to be used as a high-throughput, low-cost, and reliable methods for detecting and quantifying multiple Sudan dyes in low concentration from illegally adulterated samples.

Radiation Oncology in the Land of the Pyramids: How Sudan Continues to Push the Frontiers of Cancer Care in Eastern Africa

When faced with illness, Sudanese patients have traditionally relied primarily on folklore healers. In the recent past, Sudan increased its health care spending and placed ever-greater importance on medical education. Although traditional remedies still play an important role, Sudanese patients increasingly consult conventional medicine. Not only infectious diseases but also a rising burden of noncommunicable conditions, including cancer, represent major health care challenges. Therefore, Sudan will need to make the best out of the limited resources available and further increase investment in health care to confront these trends successfully. Sudan was one of the first African countries to recognize the importance of radiation oncology in multidisciplinary cancer care and began investing in it in the 1960s. Today, there are 4 comprehensive cancer centers in the country, which offer radiation therapy and employ 10 radiation therapy machines for a population of about 45 million people. This proportion is an indication that Sudan still has an underfunded health care system with a lack of infrastructure and human resources. The present manuscript intends to provide a well-rounded overview of radiation oncology in Sudan today.

Clinicopathologic Features of Peripheral T-Cell Lymphoma in Sub-Saharan Africa

OBJECTIVES

Peripheral T-cell lymphomas (PTCLs) are heterogeneous, clinically aggressive, and rare. Subtype distribution varies by geographic location; however, data from sub-Saharan Africa (SSA) are lacking. We sought to elucidate clinicopathologic features of PTCL in SSA.

METHODS

We reviewed PTCL consultation cases from three SSA countries. PTCL subtype was determined per 2017 World Health Organization classification. Cases with sufficient material were evaluated by polymerase chain reaction for human T-cell leukemia virus type 1 (HTLV-1) and T-cell receptor γ (TCRG) rearrangement.

RESULTS

Among 32 cases, median age was 45 years and male-to-female ratio was 1.7. Thirty (94%) of 32 cases required additional workup for subclassification. PTCL, not otherwise specified (PTCL-NOS) was the most common subtype (13/32, 41%), followed by PTCL with T-follicular helper phenotype (6/32, 19%) and systemic anaplastic large cell lymphoma (6/32, 19%). Four (16%) of 25 cases were Epstein-Barr virus positive (EBV+) (2/2 extranodal natural killer/T-cell lymphoma, 1/13 PTCL-NOS, and 1/4 angioimmunoblastic T-cell lymphoma with EBV+ immunoblasts). Two (15%) of 13 patients with PTCL-NOS were human immunodeficiency virus positive. No cases with evaluable DNA (0/15) were HTLV-1 positive, and 9 of 10 showed clonal TCRG rearrangements.

CONCLUSIONS

In comparison to Western studies, PTCLs from SSA show similar subtype distribution and male predominance but a younger age at diagnosis. Appropriate diagnosis of PTCL requires extensive ancillary testing not readily available in low-income countries, including much of SSA.

Environmental Health Research in Africa: Important Progress and Promising Opportunities

The World Health Organization in 2016 estimated that over 20% of the global disease burden and deaths were attributed to modifiable environmental factors. However, data clearly characterizing the impact of environmental exposures and health endpoints in African populations is limited. To describe recent progress and identify important research gaps, we reviewed literature on environmental health research in African populations over the last decade, as well as research incorporating both genomic and environmental factors. We queried PubMed for peer-reviewed research articles, reviews, or books examining environmental exposures and health outcomes in human populations in Africa. Searches utilized medical subheading (MeSH) terms for environmental exposure categories listed in the March 2018 US National Report on Human Exposure to Environmental Chemicals, which includes chemicals with worldwide distributions. Our search strategy retrieved 540 relevant publications, with studies evaluating health impacts of ambient air pollution (n=105), indoor air pollution (n = 166), heavy metals (n = 130), pesticides (n = 95), dietary mold (n = 61), indoor mold (n = 9), per- and polyfluoroalkyl substances (PFASs, n = 0), electronic waste (n = 9), environmental phenols (n = 4), flame retardants (n = 8), and phthalates (n = 3), where publications could belong to more than one exposure category. Only 23 publications characterized both environmental and genomic risk factors. Cardiovascular and respiratory health endpoints impacted by air pollution were comparable to observations in other countries. Air pollution exposures unique to Africa and some other resource limited settings were dust and specific occupational exposures. Literature describing harmful health effects of metals, pesticides, and dietary mold represented a context unique to Africa. Studies of exposures to phthalates, PFASs, phenols, and flame retardants were very limited. These results underscore the need for further focus on current and emerging environmental and chemical health risks as well as better integration of genomic and environmental factors in African research studies. Environmental exposures with distinct routes of exposure, unique co-exposures and co-morbidities, combined with the extensive genomic diversity in Africa may lead to the identification of novel mechanisms underlying complex disease and promising potential for translation to global public health.

Addressing Childhood Cancer in Low-Resource Countries: Current Challenges, Strategies, and Recommendations

Children and adolescents represent a small, but critically important, number of patients with cancer worldwide (14.1 million newly diagnosed adults versus 160,000 children annually). The life years saved when a child is cured of cancer are about 71 compared to 15 years for an adult in most high-income countries (HICs). In HICs, about 80% of children survive cancer. Unfortunately, in low- and middle-income countries (LMICs), the survival rates are generally 50% or less. In these resource-limited settings, only 15%-37% of children and adolescents have access to cancer treatment, and most are diagnosed with advanced-stage disease, making cure impossible.

An Estimate of the Incidence of Prostate Cancer in Africa: A Systematic Review and Meta-Analysis

BACKGROUND

Prostate cancer (PCa) is rated the second most common cancer and sixth leading cause of cancer deaths among men globally. Reports show that African men suffer disproportionately from PCa compared to men from other parts of the world. It is still quite difficult to accurately describe the burden of PCa in Africa due to poor cancer registration systems. We systematically reviewed the literature on prostate cancer in Africa and provided a continent-wide incidence rate of PCa based on available data in the region.

METHODS

A systematic literature search of Medline, EMBASE and Global Health from January 1980 to June 2015 was conducted, with additional search of Google Scholar, International Association of Cancer Registries (IACR), International Agency for Research on Cancer (IARC), and WHO African region websites, for studies that estimated incidence rate of PCa in any African location. Having assessed quality and consistency across selected studies, we extracted incidence rates of PCa and conducted a random effects meta-analysis.

RESULTS

Our search returned 9766 records, with 40 studies spreading across 16 African countries meeting our selection criteria. We estimated a pooled PCa incidence rate of 22.0 (95% CI: 19.93-23.97) per 100,000 population, and also reported a median incidence rate of 19.5 per 100,000 population. We observed an increasing trend in PCa incidence with advancing age, and over the main years covered.

CONCLUSION

Effective cancer registration and extensive research are vital to appropriately quantifying PCa burden in Africa. We hope our findings may further assist at identifying relevant gaps, and contribute to improving knowledge, research, and interventions targeted at prostate cancer in Africa.

BRCA1 point mutations in premenopausal breast cancer patients from Central Sudan

Premenopausal breast cancer (BC) is one of the most common cancers of women in rural Africa and part of the disease load may be related to hereditary predisposition, including mutations in the BRCA1 gene. However, the BRCA1 mutations associated with BC in Africa are scarcely characterized. We report here 33 BRCA1 point mutations, among which 2 novel missense variants, found in 59 Central Sudanese premenopausal BC patients. The high fractions of mutations with intercontinental and uniquely African distribution (17/33, 51.5 % and 14/33, 42.4 %, respectively) are in agreement with the high genetic diversity expected in an African population. Overall 24/33 variants (72.7 %) resulted neutral; 8/33 of unknown significance (24.3 %, including the 2 novel missense mutations); 1 (3.0 %) overtly deleterious. Notably, in silico studies predict that the novel C-terminal missense variant c.5090G>A (p.Cys1697Tyr) affects phosphopeptide recognition by the BRCA1 BRCT1 domain and may have a pathogenic impact. Genetic variation and frequency of unique or rare mutations of uncertain clinical relevance pose significant challenges to BRCA1 testing in Sudan, as it might happen in other low-resource rural African contexts.

Part I: cancer in Sudan—burden, distribution, and trends breast, gynecological, and prostate cancers

Despite the growing burden of cancer worldwide, it continues to receive low priority in Africa, across the continent and specifically in Sudan. This is due to political unrest, limited health resources, and other pressing public health issues such as infectious diseases. Lack of awareness about the magnitude of the current and future cancer burden among policy makers play a major role as well. Although, the real scope of cancer in Sudan is not known, the reported cases have increased from 303 in 1967–6303 in 2010. According to Globocan estimates, the top most common cancers in both sexes are breast, non-Hodgkin lymphoma, leukemia, esophagus, and colorectum. This review is the first of four papers that focuses on cancer, its distribution and trend as well as the risk factors most common in Sudan. It is expected that cancer will increase in Sudan as a result of migration of people from rural areas to urban cities in the pursuit of a better standard of living, which has resulted in lifestyle and behavioral changes that include tobacco chewing and smoking, unhealthy dieting, and a lack of physical activity. These changes are further exacerbated by the aging population and have made the country vulnerable to many diseases including cancer. These reviews are meant to provide a better understanding and knowledge required to plan appropriate cancer-control and prevention strategies in the country.

Occurrence of 1,1'-dimethyl-4,4'-bipyridinium (Paraquat) in irrigated soil of the Lake Chad Basin, Niger

Increased use of agrochemical products to improve yields for irrigated crops in sub-Saharan Africa has been accompanied by a significant increase in the risk of environmental contamination. Detailed examples of the fate of pesticides after initial spreading on crop fields are scarce in tropical regions, where safe practices and related health risks are poorly understood by smallholder farmers. In the semi-arid environment of the Lake Chad Basin, SE Niger, both intrinsic properties of pesticides and extrinsic factors such as soil and climate helped to characterize processes leading to an accumulation of pesticides in soils. Analysis by HPLC-UV of a 6 m deep soil profile showed the presence of Paraquat at concentrations from 953 ± 102 μg kg(-1) to 3083 ± 175 μg kg(-1) at depths between 0.80 and 2.75 m below the land surface. Soil analysis revealed that up to approximately 15 % of the total soil matrix consists of smectites, a clay mineral capable of retaining cationic pesticides such as Paraquat, and a very low content of organic matter (<0.15 wt.% TOC). Paraquat could be stored and not bioavailable in a clayey barrier at approximately 2-m depth and therefore does not represent an immediate risk for populations or environment in this form. However, if the Paraquat application rate remains constant, the clayey barrier could reach a saturation limit within 150-200 years and 180-220 years if we consider a DT50 in soil of ~1,000 days (FAO). Consequently, it could lead to a deeper infiltration and so a pollution of groundwater. Such a scenario can represent a health risk for drinking water and for the Lake Chad, which is a major resource for this densely populated region of semi-arid Africa. Further analyses should focus on deeper layers and groundwater Paraquat contents to validate or invalidate the hypothesis of storage in this clay-rich layer.

Cancers in Eastern Libya: First results from Benghazi Medical Center

AIM: To study the pattern of cancer incidence and determine the incidence rates in Eastern Libya (for the first time in a decade).

METHODS: A hospital-based registry of cancer patients was formed using records from the primary oncology center in eastern Libya - focusing on those diagnosed in the year 2012.

RESULTS: The most common malignancies in men were cancers of the colon (22.3%, n = 90), lung (20.3%, n = 82), prostate (16.1%, n = 65), pancreas (4.2%, n = 17) and liver (4.2%, n = 17). For women, they were found to be cancers of the breast (41.5%, n = 213), colon (16.4%, n = 84), uterus (8%, n = 41), ovary (5.5%, n = 28) and pancreas (3.1%, n = 16). Additionally age-standardized rates (ASR) were determined for Libya. The different cities and towns in eastern Libya were compared for any variation. The city of Beida in particular was found to have a remarkably high incidence of gastric cancer. The different findings were discussed and comparisons were made with past literature as well as the incidence rates for neighbouring countries. The incidence rates given for the eastern region showed differences from previously reported values (i.e., the rate of colon cancer was the highest in North Africa whereas other malignancies occurred less frequently). Potential explanations for the urban-rural difference as well as the difference in incidence rates were put forth. The significance of this study is that it establishes a baseline of cancer incidence which should be the backbone for any future national cancer plan in Libya.

CONCLUSION: Proper surveillance programs need to be in place and healthcare policy should be adjusted to take into account the more prevalent and pressing cancers in society.

Cancer incidence in Khartoum, Sudan: first results from the Cancer Registry, 2009-2010

In 2009, the first National Population-based Cancer Registry (NCR) was established in Sudan. We report in this study, the first data from the NCR for Khartoum State for the period 2009–2010. The NCR staff used passive and active approaches to collect data on cancer diagnosed by all means in Khartoum State. Rates were age standardized to the 2010 Sudan Standard Population and 1966 and 2000 World Standard Population and expressed per 100,000 populations. During 2009–2010, 6771 new cancer cases were registered. Of those, 3646 (53.8%) cases were in women and 3125 (46.2%) were in men. The most commonly diagnosed cancer among women was breast followed by leukemia, cervix, and ovary, and among men it was prostate cancer followed by leukemia, lymphoma, oral, colorectal, and liver. In children less than 15 years of age, leukemia was the most common cancer followed lymphoma, and cancer of the eye, bone, kidney, and the brain. The overall age-standardized rate (ASR) per 100,000 population was higher in women (124.3) than in men (90.8) using 2010 Sudan Standard Population. Similarly, it was higher in women (188.6 and 206.3 per 100,000 population) than in men (145.4 and 160.0 per 100,000 population) using 1966 and 2000 World Standard Population, respectively. The data from NCR indicated that prostate and breast as the most commonly diagnosed cancer sites in men and women in Khartoum, while cancer of the cervix trailed behind portraying a cancer picture similar to that of the developed world. Despite the study limitations, the NCR data gave a fair representation of cancer profile of Khartoum State and underscored the need for high-quality cancer registries in Sudan.

On the antiquity of cancer: evidence for metastatic carcinoma in a young man from ancient Nubia (c. 1200 BC)

Cancer, one of the world’s leading causes of death today, remains almost absent relative to other pathological conditions, in the archaeological record, giving rise to the conclusion that the disease is mainly a product of modern living and increased longevity. This paper presents a male, young-adult individual from the archaeological site of Amara West in northern Sudan (c. 1200BC) displaying multiple, mainly osteolytic, lesions on the vertebrae, ribs, sternum, clavicles, scapulae, pelvis, and humeral and femoral heads. Following radiographic, microscopic and scanning electron microscopic (SEM) imaging of the lesions, and a consideration of differential diagnoses, a diagnosis of metastatic carcinoma secondary to an unknown soft tissue cancer is suggested. This represents the earliest complete example in the world of a human who suffered metastatic cancer to date. The study further draws its strength from modern analytical techniques applied to differential diagnoses and the fact that it is firmly rooted within a well-documented archaeological and historical context, thus providing new insights into the history and antiquity of the disease as well as its underlying causes and progression.