The incidence of oesophageal cancer in Eastern Africa: identification of a new geographic hot spot?

Rural-urban disparity in cancer burden and care: findings from an Indian cancer registry

BACKGROUND

Cancer incidence and mortality vary across the globe, with nearly two-thirds of cancer-related deaths occurring in low- and middle-income countries. The rural-urban disparity in socio-demographic, behavioural, and lifestyle-related factors, as well as in access to cancer care, is one of the contributing factors. Population-based cancer registries serve as a measure for understanding the burden of cancer. We aimed to evaluate the rural-urban disparity in cancer burden and care of patients registered by an Indian population-based cancer registry.

METHODS

This study collected data from Varanasi, Uttar Pradesh, India, between 2017 and 2019. Sex and site-specific age-standardised rates for incidence and mortality per 100,000 population were calculated. Rural-urban disparities in cancer incidence and mortality were estimated through rate differences and standardised rate ratios (with 95% confidence intervals). Univariable and multivariable regressions were applied to determine any significant differences in socio-demographic and cancer-related variables according to place of residence (rural/urban). Crude and adjusted odds ratios with 95% confidence intervals were calculated.

RESULTS

6721 cancer patients were registered during the study duration. Urban patients were older and had better literacy and socioeconomic levels, while rural patients had higher odds of having unskilled or semi-skilled professions. Diagnostic and clinical confirmation for cancer was significantly higher in urban patients, while verbal autopsy-based confirmation was higher in rural patients. Rural patients were more likely to receive palliative or alternative systems of medicine, and urban patients had higher chances of treatment completion. Significantly higher incidence and mortality were observed for oral cancer among urban men and for cervical cancer among rural women. Despite the higher incidence of breast cancer in urban women, significantly higher mortality was observed in rural women.

CONCLUSIONS

Low- and middle-income countries are facing dual challenges for cancer control and prevention. Their urban populations experience unhealthy lifestyles, while their rural populations lack healthcare accessibility. The distinctness in cancer burden and pattern calls for a re-evaluation of cancer control strategies that are tailor-made with an understanding of urban-rural disparities. Context-specific interventional programmes targeting risk-factor modifications, cancer awareness, early detection, and accessibility to diagnosis and care are essential.

The microbiome and rise of early-onset cancers: knowledge gaps and research opportunities

Accumulating evidence indicates an alarming increase in the incidence of early-onset cancers, which are diagnosed among adults under 50 years of age, in the colorectum, esophagus, extrahepatic bile duct, gallbladder, liver, stomach, pancreas, as well as the bone marrow (multiple myeloma), breast, head and neck, kidney, prostate, thyroid, and uterine corpus (endometrium). While the early-onset cancer studies have encompassed research on the wide variety of organs, this article focuses on research on digestive system cancers. While a minority of early-onset cancers in the digestive system are associated with cancer-predisposing high penetrance germline genetic variants, the majority of those cancers are sporadic and multifactorial. Although potential etiological roles of diets, lifestyle, environment, and the microbiome from early life to adulthood (i.e. in one's life course) have been hypothesized, exact contribution of each of these factors remains uncertain. Diets, lifestyle patterns, and environmental exposures have been shown to alter the oral and intestinal microbiome. To address the rising trend of early-onset cancers, transdisciplinary research approaches including lifecourse epidemiology and molecular pathological epidemiology frameworks, nutritional and environmental sciences, multi-omics technologies, etc. are needed. We review current evidence and discuss emerging research opportunities, which can improve our understanding of their etiologies and help us design better strategies for prevention and treatment to reduce the cancer burden in populations.

A Genomic Analysis of Esophageal Squamous Cell Carcinoma in Eastern Africa

BACKGROUND

Esophageal squamous cell carcinoma (ESCC) comprises 90% of all esophageal cancer cases globally and is the most common histology in low-resource settings. Eastern Africa has a disproportionately high incidence of ESCC.

METHODS

We describe the genomic profiles of 61 ESCC cases from Tanzania and compare them to profiles from an existing cohort of ESCC cases from Malawi. We also provide a comparison to ESCC tumors in The Cancer Genome Atlas (TCGA).

RESULTS

We observed substantial transcriptional overlap with other squamous histologies via comparison with TCGA PanCan dataset. DNA analysis revealed known mutational patterns, both genome-wide as well as in genes known to be commonly mutated in ESCC. TP53 mutations were the most common somatic mutation in tumors from both Tanzania and Malawi but were detected at lower frequencies than previously reported in ESCC cases from other settings. In a combined analysis, two unique transcriptional clusters were identified: a proliferative/epithelial cluster and an invasive/migrative/mesenchymal cluster. Mutational signature analysis of the Tanzanian cohort revealed common signatures associated with aging and cytidine deaminase activity (APOBEC) and an absence of signature 29, which was previously reported in the Malawi cohort.

CONCLUSIONS

This study defines the molecular characteristics of ESCC in Tanzania, and enriches the Eastern African dataset, with findings of overall similarities but also some heterogeneity across two unique sites.

IMPACT

Despite a high burden of ESCC in Eastern Africa, investigations into the genomics in this region are nascent. This represents the largest comprehensive genomic analysis ESCC from sub-Saharan Africa to date.

Clinicopathological characteristics and treatment outcomes of oesophageal cancer patients in Uganda

Background

Oesophageal cancer is the seventh most common cancer and the sixth leading cause of cancer death worldwide, and its incidence varies globally. In Uganda, the incidence and trend are on the increase. However, there is a paucity of published data regarding this population's oesophageal cancer clinicopathologic characterisation and treatment outcomes.

Objectives

To study the patients' clinicopathologic characteristics and treatment outcomes of oesophageal cancer over 10 years at the Uganda Cancer Institute.

Methods

Patients' charts with histologically confirmed diagnoses of oesophageal cancer for 2009-2019 were identified. Case information, which included patient demographics, history of alcohol use or smoking, tumour location, histological type, tumour grade, clinical TNM (Tumour, Node, Metastasis) staging treatment exposure and treatment outcomes, was evaluated retrospectively. The median survival time was estimated with the Kaplan-Meier method and the median follow-up period was estimated using the reverse Kaplan-Meier.

Results

1,965 oesophageal cancer patients were identified; 1,380(70.23%) were males and 585(29.77 %) females, their mean age was 60.20 years (±12.66). Most males had a history of both alcohol consumption and smoking 640(46.38%). The lower third of the oesophagus was the most common anatomical location 771(39.24%). The majority had squamous cell carcinoma histological type 1,783(90.74%) followed by adenocarcinomas 182(9.26%) in the distal oesophagus. Poorly differentiated tumour grade 743(37.81%) was predominant. The majority of the patients were in stage IVB, 733(37.30%), and most patients were planned for the best supportive care, 731(37.20%). Radiation alone was offered to 621(31.60%) and feeding gastrostomy to 249(12.70%). Treatment outcomes: at the time of the current analysis, 58.68% had died, 1.48% were alive and 39.84% were lost to follow-up. The median follow-up period was 65 months (IQR:35.83-83.30) with a median survival time of 4.47 months (95% CI: 4.17-4.80).

Conclusion

Treatment outcomes of Ugandan oesophageal cancer patients seeking care are poor as most patients present with advanced disease. There is a significant loss of follow-up after treatment initiation. Therefore, reduction in exposure to known modifiable risk factors, early detection and timely referral for treatment strategies are needed to improve outcomes of these patients in our population. Designing interventions to improve treatment adherence is necessary.

An international report on bacterial communities in esophageal squamous cell carcinoma

The incidence of esophageal squamous cell carcinoma (ESCC) is disproportionately high in the eastern corridor of Africa and parts of Asia. Emerging research has identified a potential association between poor oral health and ESCC. One possible link between poor oral health and ESCC involves the alteration of the microbiome. We performed an integrated analysis of four independent sequencing efforts of ESCC tumors from patients from high- and low-incidence regions of the world. Using whole genome sequencing (WGS) and RNA sequencing (RNAseq) of ESCC tumors from 61 patients in Tanzania, we identified a community of bacteria, including members of the genera Fusobacterium, Selenomonas, Prevotella, Streptococcus, Porphyromonas, Veillonella and Campylobacter, present at high abundance in ESCC tumors. We then characterized the microbiome of 238 ESCC tumor specimens collected in two additional independent sequencing efforts consisting of patients from other high-ESCC incidence regions (Tanzania, Malawi, Kenya, Iran, China). This analysis revealed similar ESCC-associated bacterial communities in these cancers. Because these genera are traditionally considered members of the oral microbiota, we next explored whether there was a relationship between the synchronous saliva and tumor microbiomes of ESCC patients in Tanzania. Comparative analyses revealed that paired saliva and tumor microbiomes were significantly similar with a specific enrichment of Fusobacterium and Prevotella in the tumor microbiome. Together, these data indicate that cancer-associated oral bacteria are associated with ESCC tumors at the time of diagnosis and support a model in which oral bacteria are present in high abundance in both saliva and tumors of some ESCC patients.

Tobacco and other risk factors for esophageal squamous cell carcinoma in Lilongwe Malawi: Results from the Lilongwe esophageal cancer case: Control study

OBJECTIVE

Esophageal cancer is the second commonest cancer in Malawi, and 95% of all cases are esophageal squamous cell carcinoma (ESCC). Very little is known about the epidemiology of ESCC in Malawi including risk factors. The main objective of the study was to evaluate and describe risk factors of ESCC in Malawi.

METHODS

We conducted a case-control study from 2017 to 2020 at two hospitals in Lilongwe, Malawi and consenting adults were eligible for inclusion. Endoscopy was conducted on all cases and biopsies were obtained for histological confirmation. Controls were selected from patients or their guardians in orthopedic, dental and ophthalmology wards and they were frequency matched by sex, age, and region of origin to cases. An electronic structured questionnaire was delivered by a trained interviewer. Multivariate conditional logistic regression models were used to assess the associations between subject characteristics, habits, and medical history and risk of ESCC.

RESULTS

During the study period, 300 cases and 300 controls were enrolled into the study. Median age of cases and controls was 56 years and 62% of the cases were male. Among cases, 30% were ever cigarette smokers as were 22% of controls. Smoking cigarettes had an adjusted odds ratio of 2.4 (95% CI 1.4-4.2 p = 0.003). HIV+ status was present in 11% of cases and 4% controls, which resulted in an adjusted odds ratio was 4.0 (95% CI 1.8-9.0 p = 0.001). Drinking hot tea was associated with an adjusted odd ratio of 2.9 (95% CI 1.3-6.3 p = 0.007). Mold on stored grain has an adjusted odd ratio of 1.6 (95% CI 1.1-2.5 p = 0.021).

CONCLUSION

Reducing smoking cigarettes, consumption of scalding hot tea, and consumption of contaminated grain, could potentially help reduce the burden of ESCC in Malawi. Further investigation of the association between HIV status and ESCC are warranted.

Prevalence of esophageal squamous dysplasia in relatives of patients with esophageal cancer in Southwestern Kenya

BACKGROUND

Esophageal squamous cell carcinoma (ESCC) and its asymptomatic precursor lesion, esophageal squamous dysplasia (ESD), are common in East Africa. It is unknown whether family history of esophageal cancer is a risk factor for both ESD and ESCC in Africa, and whether family members of affected persons should be screened.

METHODS

We recruited 296 asymptomatic adult first-degree relatives of ESCC patients residing in southwestern Kenya. Participants completed questionnaires and underwent endoscopy with Lugol's iodine staining and biopsy to determine the prevalence of ESD. Prevalence comparisons were made with a prior population-based cohort from the same catchment area who also underwent Lugol's chromoendoscopy.

RESULTS

Mean age was 40.7 years, compared to 62.7 years in the prior population study. The overall prevalence of ESD/ESCC among first-degree relatives was 14.7%, comparable to the background population prevalence of 14.4%, and this comparability remained even after adjusting for the different age distributions of the studies. Post-primary education was the only measured variable that was associated with a decreased risk of ESD/ESCC (adjusted OR=0.31, 95% CI: 0.11, 0.83). There was heterogeneity in the ESD prevalence across families, even after adjustments for varying age and other measured factors.

CONCLUSIONS

The prevalence of esophageal squamous dysplasia among first-degree relatives of persons with ESCC was similar to that of the background population of southwestern Kenya; however, there was heterogeneity in ESD prevalence between families, suggesting other genetic or environmental factors may influence family prevalence. Further study of families with a high prevalence of ESD or ESCC is justified.

Demographic, endoscopic and histological profile of esophageal cancer at the Gastroenterology Department of Maputo Central Hospital from January 2016 to December 2018

INTRODUCTION

esophageal cancer is a major public health problem in Mozambique. It is the nineth most common cancer worldwide in terms of incidence (604.000 new cases/year), and sixth in overall mortality (544.076 deaths/year). In Mozambique esophageal cancer was the seventh most common cancer in males and the fifth in females between 1991 and 2008.

METHODS

it was done a cross-sectional hospital-based epidemiological study, using secondary demographics endoscopic and pathologic features data. A retrospective analysis of the existing information of patients classified as esophageal cancer diagnosed with upper gastrointestinal endoscopy observed from January 1^st, 2016 to December 31^st, 2018 at the Gastroenterology Service of Maputo Central Hospital. A coding sheet was created a priori, and data analysed in SPSS version 20.

RESULTS

of the 205 cases with complete records where included in the analysis, there was a higher frequency of females with 56.6% (116/205). The average age was 59.5 years with standard deviation of ± 12.9 years. Most of the patients were native of southern Mozambique, with 92.7% (190/205), of which Maputo made up 53.2% (109/205). Regarding race, 99.5% (204/205) were black. The most affected endoscopic location was the middle third with 48.8% (100/205), followed by the lower third with 29.8% (61/205) and the upper third with 21.5% (44/205). Squamous cell carcinoma was the most frequent, with 92.7% (190/205), followed by adenocarcinoma with 4.9% (10/205).

CONCLUSION

due to the high number of observed cases of esophageal cancer, a high degree of clinical suspicion is needed for timely diagnosis and more effective treatment. Updated prevalent studies are needed throughout the country to understand the true impact of esophageal cancer on the Mozambican population.

Risk Factors Associated With Early-Onset Esophageal Cancer in Tanzania

Eastern Africa is one of several regions affected by high incidence rates of esophageal squamous cell carcinoma (ESCC). A unique epidemiologic feature of ESCC in Eastern Africa is the high incidence in young people, with one-third of cases diagnosed at age < 45 years. This study aimed to investigate risk factors for early-onset ESCC in Tanzania through a secondary analysis of a matched case-control study.

Data from Tanzania show esophageal cancer risk factors in East Africa may differ across age groups.

Treatment outcomes of esophageal cancer in Eastern Africa: protocol of a multi-center, prospective, observational, open cohort study

Background

Esophageal squamous cell carcinoma (ESCC) is a major cause of cancer morbidity and mortality in Eastern Africa. The majority of patients with ESCC in Eastern Africa present with advanced disease at the time of diagnosis. Several palliative interventions for ESCC are currently in use within the region, including chemotherapy, radiation therapy with and without chemotherapy, and esophageal stenting with self-expandable metallic stents; however, the comparative effectiveness of these interventions in a low resource setting has yet to be examined.

Methods

This prospective, observational, multi-center, open cohort study aims to describe the therapeutic landscape of ESCC in Eastern Africa and investigate the outcomes of different treatment strategies within the region. The 4.5-year study will recruit at a total of six sites in Kenya, Malawi and Tanzania (Ocean Road Cancer Institute and Muhimbili National Hospital in Dar es Salaam, Tanzania; Kilimanjaro Christian Medical Center in Moshi, Tanzania; Tenwek Hospital in Bomet, Kenya; Moi Teaching and Referral Hospital in Eldoret, Kenya; and Kamuzu Central Hospital in Lilongwe, Malawi). Treatment outcomes that will be evaluated include overall survival, quality of life (QOL) and safety. All patients (≥18 years old) who present to participating sites with a histopathologically-confirmed or presumptive clinical diagnosis of ESCC based on endoscopy or barium swallow will be recruited to participate. Key clinical and treatment-related data including standardized QOL metrics will be collected at study enrollment, 1 month following treatment, 3 months following treatment, and thereafter at 3-month intervals until death. Vital status and QOL data will be collected through mobile phone outreach.

Discussion

This study will be the first study to prospectively compare ESCC treatment strategies in Eastern Africa, and the first to investigate QOL benefits associated with different treatments in sub-Saharan Africa. Findings from this study will help define optimal management strategies for ESCC in Eastern Africa and other resource-limited settings and will serve as a benchmark for future research.

Trial registration

This study was retrospectively registered with the ClinicalTrials.gov database on December 15, 2021, NCT05177393.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-021-09124-5.

Risk factors for esophageal cancer in a high-incidence area of Malawi

PURPOSE

To explore associations of nutritional, infectious, and lifestyle factors with esophageal cancer (EC) occurrence in a high-risk area of Malawi.

METHODS

This case-control study was performed with 227 patients undergoing endoscopy for dysphagia or other upper gastrointestinal complaints. Data on clinicopathological characteristics and risk factors were collected using a questionnaire developed for this study specifically. Ninety-eight blood samples were collected and the prevalence of antibodies against human immunodeficiency virus, herpes simplex virus, cytomegalovirus, Epstein-Barr virus, varicella-zoster virus, and Helicobacter pylori were determined serologically.

RESULTS

The tumor and control groups comprised 157 (69.2%) and 70 (31.8%) patients, respectively. Patients with tumors were significantly older than controls (55.5 vs. 43.5 years, p < 0.001). The male/female ratio did not differ between groups (59% and 54% male, respectively; p = 0.469). EC was associated with smoking (p < 0.001), and alcohol consumption (p = 0.020), but 43% of patients with tumors did not smoke or drink. EC was associated with the consumption of hot food and tea (p = 0.003) and smoked fish (p = 0.011). EC was not associated with any serologically investigated infectious agents. In an age adjusted binary logistic regression analysis of all nutritive factors, only locally made alcohol was significant [odds ratio (OR), 9.252; 95% confidence interval (CI), 1.455-58.822; p = 0.018].

CONCLUSIONS

Apart from alcohol consumption and smoking, the consumption of hot food or tea and smoked fish are associated with EC. Locally distilled alcohol consumption increases the EC risk in Malawi.

Cancer Mortality Patterns in Tanzania: A Retrospective Hospital-Based Study, 2006-2015

PURPOSE

This retrospective study sought to determine the type, burden, and pattern of cancer deaths in public hospitals in Tanzania from 2006 to 2015.

METHODS

This study analyzed data on cancer mortality in 39 hospitals in Tanzania. Data on the age and sex of the deceased and type of cancer were extracted from hospital death registers and report forms. Cancer types were grouped according to the 10th revision of the International Classification of Diseases. Age-standardized mortality rates and cancer mortality patterns were analyzed. A χ² test was used to examine the association between common cancers and selected covariates.

RESULTS

A total of 12,621 cancer-related deaths occurred during the 10-year period, which translates to an age-standardized hospital-based mortality rate of 47.8 per 100,000 population. Overall, the number of deaths was notably higher (56.5%) among individuals in the 15- to 59-year-old age category and disproportionately higher among females than males (P = .0017). Cancers of the cervix, esophagus, and liver were the 3 major causes of death across all study hospitals in Tanzania. Cancers of the cervix, esophagus, and liver were the largest contributors to mortality burden among females. Among males, cancers of the esophagus, liver, and prostate were the leading cause of mortality.

CONCLUSION

There is an increasing trend in cancer mortality over recent years in Tanzania, which differs with respect to age, sex, and geographic zones. These findings provide a basis for additional studies to ascertain incidence rates and survival probabilities, and highlight the need to strengthen awareness campaigns for early detection, access to care, and improved diagnostic capabilities.

Indoor wood combustion, carcinogenic exposure and esophageal cancer in southwest Kenya

BACKGROUND

Exposure to polycyclic aromatic hydrocarbons (PAHs) is a risk factor for esophageal squamous cell carcinoma (ESCC) in high-incidence areas of China, Iran and Brazil, but PAH assessments have not been conducted in East Africa, another ESCC hot spot.

OBJECTIVE

To evaluate demographic or lifestyle factors associated with the PAH biomarker concentrations in the study population, and whether PAH metabolite concentrations showed any associations with esophageal precancerous lesions.

METHODS

We recruited a community-based sample of 289 asymptomatic adults from a rural area of Kenya and performed Lugol's chromoendoscopy to detect esophageal squamous dysplasia (ESD); participants completed a questionnaire and provided a spot urine specimen. We analyzed urine for seven hydroxylated metabolites of naphthalene, fluorene, phenanthrene, and pyrene at the U.S. National Center for Environmental Health, and compared creatinine-corrected PAH metabolite concentrations with questionnaire data and the presence of ESD.

RESULTS

PAH metabolite concentrations among never tobacco users in these rural Kenya residents were 2.4-28.1 times higher than those reported from never tobacco users in Iran, Brazil and the USA. Female sex, cooking indoors, having no post-primary education, and age <50, but not tobacco use, were positively and significantly associated with PAH metabolite concentrations. Almost all participants used wood as cooking fuel. Nine participants had advanced ESD. Adjusted logistic regression showed a significant association between 2-hydroxynaphthalene (OR = 4.19, 95%CI: 1.01-17.47) and advanced ESD. All other PAH metabolites had positive but non-significant associations with advanced ESD.

CONCLUSIONS

Urinary PAH metabolite concentrations among never tobacco users are markedly higher in this group from Kenya than in other populations and are associated with indoor cooking with wood on open, unvented stoves. These metabolite concentrations were also associated with the presence of advanced esophageal dysplasia. Our findings underline the importance of assessing alternative cooking conditions to reduce PAH exposure in this population.

Trends in the incidence of cancer in Kampala, Uganda, 1991 to 2015

Trends in the incidence of cancer in the population of Kyadondo County, Uganda-which comprises the city of Kampala and a peri-urban hinterland-are presented for a period of 25 years (1991-2015) based on data collected by the Kampala Cancer Registry. Incidence rates have risen overall-age-adjusted rates are some 25% higher in 2011 to 2015 compared with 1991 to 1995. The biggest absolute increases have been in cancers of the prostate, breast and cervix, with rates of some 100% (prostate), 70% (breast) and 45% (cervix) higher in 2010 to 2015 than in 1991 to 1995. There were also increases in the incidence of cancers of the esophagus and colon-rectum (statistically significant in men), while the incidence of liver cancer-the fifth most common in this population-increased until 2007, and subsequently declined. By far the most commonly registered cancer over the 25-year period was Kaposi sarcoma, but the incidence has declined, consistent with the decreasing population-prevalence of HIV. Non-Hodgkin lymphomas, also AIDS-related, increased in incidence until 2006/2007 and then declined-possibly as a result of availability of antiretroviral therapy. The trends reflect the changing lifestyles of this urban African population, as well as the consequences of the epidemic of HIV/AIDS and the availability of treatment with ARVs. At the same time, it highlights the fact that the decreases in cancer of the cervix observed in high and upper-middle income countries are not a consequence of changes in lifestyle, but demand active intervention through screening (and, in the longer term, vaccination).

Changes in the Incidence of Cancer in Bulawayo, Zimbabwe over a 50-Year Period

BACKGROUND

The cancer registry of Bulawayo (Zimbabwe) operated for 15 years in the preindependence period (1963-77), and was restarted in 2011. This allows comparison of incidence of cancers over a period of almost 50 years.

METHODS

Age-standardized rates, with SEs, were calculated for 1963-1972 and 2011-2015. Detailed results are presented for those cancers for which there was a significant (P < 0.05) change in the rates between the two periods.

RESULTS

There were declines in the rates of those cancers previously known to be common in East and Southern Africa (esophagus, liver, bladder), and the emergence of cancers associated with "westernization" of lifestyles (breast, prostate, large bowel). Cancers related to infection with HIV-AIDS (Kaposi sarcoma, non-Hodgkin lymphoma, eye cancers) have come to comprise a much larger proportion of the total burden, and cancer of the cervix (also AIDS-related) has shown a large increase in incidence-as elsewhere in sub-Saharan Africa (SSA). More surprising is the decline in cancer of the lung-formerly very high, but by 2011-2015, despite little change in the prevalence of smoking, rates were low-close to the average for SSA. This may relate, in part, to a decline in the numbers of miners, and ex-miners, residing in the city.

CONCLUSIONS

The changes in incidence are largely explained by differences in past exposure to environmental risk factors.

IMPACT

Few datasets from SSA can document temporal changes in the cancer epidemic on the continent. There are some anticipated observations, as well as unexpected findings meriting further investigation.

Analysis of cancer diagnoses from 2015-2019 within Machakos County, Kenya, support establishment of Cancer Centre in 2019 likely changing referral patterns

Background: In Kenya, cancer is an increasing public health challenge, with an estimated 48,000 new cancer cases and over 33,000 deaths recorded each year. Machakos County, Kenya, recently opened a cancer centre with an aim of bringing cancer services such as surgical oncology, chemotherapy, radiotherapy, and pathological services closer to the residents of Machakos County. The county is also one of four counties selected for the universal health coverage pilot programme making it uniquely poised to inform cancer control programs at the local, national, and international levels. Methods: This study aimed to build a cancer database to enable future population-based cancer studies by reviewing cancer diagnosis records for selected major public hospitals in Machakos County from 2015-2019. Medical records data were retrieved from Machakos Level 5 Hospital and Kangundo, Matuu, Kathiani and Mwala Level 4 Hospitals. Results: A total of 522 cancer cases were recorded across the study period with more than a third (N=172, 33%) diagnosed August-December of 2019 when the Machakos Cancer Centre opened. Among the cancers diagnosed, the majority were in women (59.2%), with cervix uteri (n=106, 34.3%) followed by breast (n=62, 20.1%) as the most common cancers. For males, oesophagus (n=52, 24.4%) followed by prostate (n=43, 20.2%) were the most common cancer types. The highest crude rates per 100,000 persons were for Kangundo 67.4 and Matungulu 53.2 subcounties. Conclusion: It is clear that access to cancer care treatment will change referral patterns for residents in Machakos County and with the establishment of this database we expect to enable future population-based surveillance of the cancer burden and research studies, to inform cancer control programs.

Optimal management of esophageal cancer in Africa: A systemic review of treatment strategies

Esophageal cancer (EC) is a leading cause of cancer morbidity and mortality in Africa. Despite the high burden of disease, optimal management strategies for EC in resource-constrained settings have yet to be established. This systematic review evaluates the literature on treatments for EC throughout Africa and compares the efficacy and safety of varying treatment strategies in this context (PROSPERO CRD42017071546). PubMed, Embase and African Index Medicus were searched for studies published on treatment strategies for EC in Africa from 1980 to 2020. Searches were supplemented by examining bibliographies of included studies and relevant conference proceedings. Methodological quality/risk of bias was assessed using the Cochrane Risk-of-Bias tool and the Newcastle-Ottawa Scale. Forty-six studies were included. Case series constituted the majority of studies: 13 were case series reporting on outcomes of esophagectomies, 17 on palliative luminal or surgical interventions, four on radiotherapy and three on concurrent chemoradiation. Nine randomized controlled trials were identified, of which four prospectively compared different treatment modalities (one investigating radiotherapy vs chemoradiation, three evaluating rigid plastic stents vs other treatments). This review summarizes the research on EC treatments in Africa published over the last four decades and outlines critical gaps in knowledge related to management in this context. Areas in need of further research include (a) evaluation of the safety and efficacy of neoadjuvant therapy in patients with locally advanced disease; (b) strategies to improve long-term survival in patients treated with definitive chemoradiation; and (c) the comparative effectiveness of modern palliative interventions, focusing on quality of life and survival as outcome measures.

Cancer Incidence and Distribution at a Tertiary Care Hospital in Somalia from 2017 to 2020: An Initial Report of 1306 Cases

Purpose

To determine the type, frequency and distribution of all cancers in Somalia from 2017 to 2020.

Patients and Methods

This retrospective and descriptive study included the review of a total of 5238 pathology reports obtained from the medical records of the Somalia Turkey Recep Tayyip Erdogan Education and Research Hospital. Patient characteristics, lesion localization, and histopathology were recorded. Patients with an unconfirmed cancer diagnosis, borderline tumors, intraepithelial neoplasms and metastatic cancers were excluded from the study. The cases were classified according to gender, age, and organ involvement.

Results

Of the 1306 patients included in the study, 50.9% (n=666) were female and 49.1% (n=640) were male, and the mean age was 51.1±19.4 years. Of the cases, 5.1% (n=67) were pediatric (0–17 years) and 35.8% (n=468) were in the 18–50 years range. The most common cancer was esophageal cancer (EC) for the overall data (n=284; 21.7%) and in both genders. EC peaked in the fifth decade, and the most common histological type was squamous cell carcinoma (n=256; 91.1%). Liver cancer was the second most common cancer overall (n=99; 7.6%) and in men (n=67; 10.5%). Cervical cancer was the second most common cancer among women (n=88; 13.3%) and ranked fourth in terms of overall incidence (n=88; 6.7%). Breast cancer was the third most common overall (n=95; 7.3%) and in women (n= 87; 13.1%).

Conclusion

This study shows that in Somalia, EC is the most common cancer in both genders. These high rates in Somalia suggest that environmental factors and dietary habits may have an effect. To reduce the incidence of EC and prevent its development, the population of Somalia should be educated and effective planning should be undertaken.

Frequent HIV and Young Age Among Individuals With Diverse Cancers at a National Teaching Hospital in Malawi

Purpose

Cancer surveillance provides a critical evidence base to guide cancer control efforts, yet population-based coverage in Africa is sparse. Hospital-based registries may help fill this need by providing local epidemiologic data to guide policy and forecast local health care needs. We report the epidemiology of patients with cancer recorded by a de novo hospital-based cancer registry at Kamuzu Central Hospital, Malawi, the sole provider of comprehensive oncology services for half the country and location of a high-volume pathology laboratory.

Methods

We conducted active case finding across all hospital departments and the pathology laboratory from June 2014 to March 2016. Patient demographics, tumor characteristics, treatment, and HIV status were collected. We describe epidemiology of the cancer caseload, registry design, and costs associated with registry operations.

Results

Among 1,446 registered patients, Kaposi sarcoma and cervical cancer were the most common cancers among men and women, respectively. Burkitt lymphoma was most common cancer among children. The current rate of pathology confirmation is 65%, a vast improvement in the diagnostic capacity for cancer through the hospital’s pathology laboratory. Among leading cancer types, an alarming proportion occurred at young ages; 50% of Kaposi sarcoma and 25% of esophageal, breast, and cervical cancers were diagnosed among those younger than 40 years of age. A systematic, cross-sectional assessment of HIV status reveals a prevalence of 58% among adults and 18% among children.

Conclusion

We report a high caseload among typically young patients and a significant burden of HIV infection among patients with cancer. In low- and middle-income countries with intermittent, sparse, or nonexistent cancer surveillance, hospital-based cancer registries can provide important local epidemiologic data while efforts to expand population-based registration continue.

Systematic review and meta-analysis of esophageal cancer in Africa: Epidemiology, risk factors, management and outcomes

BACKGROUND

Esophageal cancer (EC) is associated with a poor prognosis, particularly so in Africa where an alarmingly high mortality to incidence ratio prevails for this disease.

AIM

To provide further understanding of EC in the context of the unique cultural and genetic diversity, and socio-economic challenges faced on the African continent.

METHODS

We performed a systematic review of studies from Africa to obtain data on epidemiology, risk factors, management and outcomes of EC. A non-systematic review was used to obtain incidence data from the International Agency for Research on Cancer, and the Cancer in Sub-Saharan reports. We searched EMBASE, PubMed, Web of Science, and Cochrane Central from inception to March 2019 and reviewed the list of articles retrieved. Random effects meta-analyses were used to assess heterogeneity between studies and to obtain odds ratio (OR) of the associations between EC and risk factors; and incidence rate ratios for EC between sexes with their respective 95% confidence intervals (CI).

RESULTS

The incidence of EC is higher in males than females, except in North Africa where it is similar for both sexes. The highest age-standardized rate is from Malawi (30.3 and 19.4 cases/year/100000 population for males and females, respectively) followed by Kenya (28.7 cases/year/100000 population for both sexes). The incidence of EC rises sharply after the age of 40 years and reaches a peak at 75 years old. Meta-analysis shows a strong association with tobacco (OR 3.15, 95%CI: 2.83-3.50). There was significant heterogeneity between studies on alcohol consumption (OR 2.28, 95%CI: 1.94-2.65) and on low socioeconomic status (OR 139, 95%CI: 1.25-1.54) as risk factors, but these could also contribute to increasing the incidence of EC. The best treatment outcomes were with esophagectomy with survival rates of 76.6% at 3 years, and chemo-radiotherapy with an overall combined survival time of 267.50 d.

CONCLUSION

Africa has high incidence and mortality rates of EC, with preventable and non-modifiable risk factors. Men in this setting are at increased risk due to their higher prevalence of tobacco and alcohol consumption. Management requires a multidisciplinary approach, and survival is significantly improved in the setting of esophagectomy and chemoradiation therapy.

Esophageal cancer in Mozambique: should mycotoxins be a concern?

Fumonisin B1 (FB1) is a mycotoxin frequently found in agricultural commodities. The toxin poses a considerable risk for human and animal health. FB1 is among several mycotoxins produced by Fusarium spp. contaminating virtually any cereal and other Poaceae. Their intracellular action includes the promotion of oxidative stress through the generation of reactive oxygen species (ROS) that damage biomolecules such as DNA. These toxic effects were observed in vivo and in vitro. However, the association between esophageal lesions and oxidative stress induced by FB1. Studies in China, Iran and South Africa showed higher exposure to fumonisins in areas with higher risk of esophageal cancer (EC). Exposure to mycotoxins may be inevitable in Mozambique. How mycotoxins, particularly fumonisins from the contaminated food, can be associated with the emergence of EC in Mozambique? Herein, we revise the literature and present some pieces of evidence in order to highlight the burden of mycotoxins and to provide evidence-based considerations for the stakeholders involved in the management of the EC agenda in Mozambique. The information presented herein supports the need to implement novel and/or to revisit the existent detoxification methods to reduce the global burden of mycotoxins and its outcomes in health management.

Cancer incidence in older adults in selected regions of sub-Saharan Africa, 2008-2012

Although the countries of Sub-Sharan Africa represent among the most rapidly growing and aging populations worldwide, no previous studies have examined the cancer patterns in older adults in the region as a means to inform cancer policies. Using data from Cancer Incidence in Five Continents, we describe recent patterns and trends in incidence rates for the major cancer sites in adults aged ≥60 years and in people aged 0-59 for comparison in four selected population-based cancer registries in Kenya (Nairobi), the Republic of South Africa (Eastern Cape Province), Uganda (Kyadondo country), and Zimbabwe (Harare blacks). Over the period 2008-2012, almost 9,000 new cancer cases were registered in older adults in the four populations, representing one-third of all cancer cases. Prostate and esophageal cancers were the leading cancer sites in older males, while breast, cervical and esophageal cancers were the most common among older females. Among younger people, Kaposi sarcoma and non-Hodgkin lymphoma were common. Over the past 20 years, incidence rates among older adults have increased in both sexes in Uganda and Zimbabwe while rates have stabilized among the younger age group. Among older adults, the largest rate increase was observed for breast cancer (estimated annual percentage change: 5% in each country) in females and for prostate cancer (6-7%) in males. Due to the specific needs of older adults, tailored considerations should be given to geriatric oncology when developing, funding and implementing national and regional cancer programmes.

Investigating tea temperature and content as risk factors for esophageal cancer in an endemic region of Western Kenya: Validation of a questionnaire and analysis of polycyclic aromatic hydrocarbon content

BACKGROUND

Esophageal squamous cell carcinoma (ESCC) is common in certain areas worldwide. One area, western Kenya, has a high risk of ESCC, including many young cases (<30 years old), but has limited prior study of potential risk factors. Thermal injury from hot food and beverages and exposure to polycyclic aromatic hydrocarbons (PAHs) have been proposed as important risk factors for ESCC in other settings. The beverage of choice in western Kenya is milky tea (chai).

METHODS

Healthy individuals >18 years of age who were accompanying relatives to an endoscopy unit were recruited to participate. The preferred initial temperature of chai consumption in these adults was measured by questionnaire and digital thermometer. Comparisons of these results were assessed by kappa statistics. Concentrations of 26 selected PAHs were determined by gas chromatography/mass spectrometry in samples of 11 brands of commercial tea leaves commonly consumed in Kenya.

RESULTS

Kappa values demonstrated moderate agreement between questionnaire responses and measured temperatures. The mean preferred chai temperatures were 72.1 °C overall, 72.6 °C in men (n = 78), and 70.2 °C in women (n = 22; p < 0.05). Chai temperature did not significantly differ by age or ethnic group. The PAH levels in the commercial Kenyan tea leaves were uniformly low (total PAH < 300 ng/g of leaves).

CONCLUSIONS

Study participants drink chai at higher temperatures than previously reported in other high-risk ESCC regions. Chai is not, however, a source of significant PAH exposure. Very hot chai consumption should be further evaluated as a risk factor for ESCC in Kenya with the proposed questionnaire.

Clinical and Pathologic Profiles of Esophageal Cancer in Mozambique: A Study of Consecutive Patients Admitted to Maputo Central Hospital

PURPOSE

Eastern Africa was recently described as a high-incidence geographic area for esophageal cancer. Mozambique is included in this region. This study aimed to characterize this malignant disease at Maputo Central Hospital (MCH) to develop a global program for esophageal cancer management in Mozambique.

METHODS

MCH records from between 2012 and 2016 were used to assess the clinical, pathologic, and outcome profiles of esophageal tumors. A descriptive analysis of data collected was performed. Overall survival was evaluated using Kaplan-Meier curves.

RESULTS

In the study, 522 consecutive patient cases of esophageal cancer were recorded. The median patient age was 56.1 years (range, 27 to 97 years); 291 (55.7%) patients were women, and 230 (44.1%) were men. Regarding tumor site, 113 patients (21.6%) had a tumor in the lower third, 154 (29.5%) in the middle, and 50 (9.6%) in the upper third of the esophagus; in the remaining 196 (37.5%), tumor site was unknown. Squamous cell carcinoma comprised 94.4% of cases with documented histopathology (74.9% of the sample). Surgical treatment was possible in 32 patients (6.1%). Disease stage was documented only in these 32 surgical patients; 28.1%, 53.1%, and 18.8% had stage I, II, and III disease, respectively. The remaining patient cases seemed to involve clinically advanced tumors. The median follow-up time was of 1.6 months. The median survival time was of 3.5 months for all patients; for patients treated with curative intent, it was of 8.7 months.

CONCLUSION

Esophageal carcinoma is a common malignant tumor at MCH and is diagnosed in the advanced stages resulting in poor prognosis. Therefore, implementation of an Esophageal Cancer Program in Mozambique is essential.

Five-year single-centre experience of carcinoma of the oesophagus from Blantyre, Malawi

Background

Oesophageal squamous cell carcinoma (OSCC) is increasing worldwide and has an exceptionally high prevalence in certain distinct geographical locations such as the African oesophageal SCC corridor. Despite this, there is a paucity of evidence to characterise the disease particularly in the Malawian context.

Method

We retrospectively audited our endoscopy database over 5 years, including for patient demographics, endoscopy findings, therapeutic intervention and recommendations for treatment.

Results

1586 patients with oesophageal cancer were identified from a total of 5882 endoscopy records from 2013 to 2017. Our cohort showed a larger proportion of oesophageal cancers found higher in the oesophagus compared with other African studies and a female preponderance in this upper-oesophagus disease subset though a male preponderance overall. 39% of patients with oesophageal cancer underwent bougie dilatation and 11% underwent palliative stent placement, which likely reflects local availability of resources.

Conclusion

This study validates the observation that OSCC predominates in sub-Saharan Africa in Malawi over other forms of oesophageal carcinoma, though our cohort appears to have subtly distinct demographics and disease-specific data. This highlights the need to prioritise preventative and therapeutic strategies for OSCC in this and similar settings.

The African Esophageal Cancer Consortium: A Call to Action

Esophageal cancer is the eighth most common cancer worldwide and the sixth most common cause of cancer-related death; however, worldwide incidence and mortality rates do not reflect the geographic variations in the occurrence of this disease. In recent years, increased attention has been focused on the high incidence of esophageal squamous cell carcinoma (ESCC) throughout the eastern corridor of Africa, extending from Ethiopia to South Africa. Nascent investigations are underway at a number of sites throughout the region in an effort to improve our understanding of the etiology behind the high incidence of ESCC in this region. In 2017, these sites established the African Esophageal Cancer Consortium. Here, we summarize the priorities of this newly established consortium: to implement coordinated multisite investigations into etiology and identify targets for primary prevention; to address the impact of the clinical burden of ESCC via capacity building and shared resources in treatment and palliative care; and to heighten awareness of ESCC among physicians, at-risk populations, policy makers, and funding agencies.

Risk factors for common cancers among patients at Kamuzu Central Hospital in Lilongwe, Malawi: A retrospective cohort study

Background

Little is known about risk factors for different cancers in Malawi. This study aimed to assess risk factors for and epidemiologic patterns of common cancers among patients treated at Kamuzu Central Hospital (KCH) in Lilongwe, and to determine the prevalence of Human Immunodeficiency Virus (HIV) infection in the same population.

Methods

We analysed data from the hospital-based KCH cancer registry, from June 2009 to September 2012, including data from a nested substudy on coinfections among cancer patients. Demographics and behavioural variables, including smoking and alcohol use, were collected through personal interviews with patients. We assessed HIV prevalence across cancer types. The distribution of cancer types was reported overall and by gender. Logistic regression was used to assess risk factors associated with common cancer types.

Results

Data from 504 registered cancer patients were included—300 (59.5%) were female and 204 (40.5%) were male. Mean age was 49 years (standard deviation, SD = 16). There were 343 HIV-negative patients (71.2%), and 139 (28.8%) were HIV-positive. The commonest cancers were oesophageal (n = 172; 34.5%), cervical (n = 109; 21.9%), and Kaposi's sarcoma (KS) (n = 52; 10.4%). Only 18% of cancer cases were histologically confirmed. Patients with oesophageal cancer were likely to be older than 50 years (odds ratio, OR = 2.22), male (OR = 1.47), and smokers (OR = 2.02). Kaposi's sarcoma patients had the highest odds (OR = 54.4) of being HIV-positive and were also more likely to be male (OR = 6.02) and smokers. Cervical cancer patients were more likely to be HIV-positive (OR = 2.2) and less than 50 years of age.

Conclusions

Age, smoking, and HIV are important risk factors for the 3 commonest cancer types (oesophageal, KS, and cervical) at this teaching hospital in Malawi. HIV is the single most important risk factor for Kaposi's sarcoma and cervical cancer.

Cross sectional study of serum selenium concentration and esophageal squamous dysplasia in western Kenya

Background

Low serum selenium status has been associated with increased risk of esophageal squamous cell carcinoma (ESCC). East Africa is a region of high ESCC incidence and is known to have low soil selenium levels, but this association has not previously been evaluated. In this study we assessed the association of serum selenium concentration and the prevalence of esophageal squamous dysplasia (ESD), the precursor lesion of ESCC, in a cross-sectional study of subjects from Bomet, Kenya.

Methods

294 asymptomatic adult residents of Bomet, Kenya completed questionnaires and underwent endoscopy with Lugol’s iodine staining and biopsy for detection of ESD. Serum selenium concentrations were measured by instrumental neutron activation analysis. Odds ratios (OR) and confidence intervals (95% CI) for associations between serum selenium and ESD were calculated using unconditional logistic regression.

Results

The mean serum selenium concentration was 85.5 (±28.3) μg/L. Forty-two ESD cases were identified (14% of those screened), including 5 (12%) in selenium quartile 1 (Q1), 5 (12%) in Q2, 15 (36%) in Q3, and 17 (40%) in Q4. Higher serum selenium was associated with prevalence of ESD (Q4 vs Q1: OR: 3.03; 95% CI: 1.05–8.74) and this association remained after adjusting for potential confounders (Q4 vs Q1: OR: 3.87; 95% CI: 1.06–14.19).

Conclusion

This is the first study to evaluate the association of serum selenium concentration and esophageal squamous dysplasia in an African population at high risk for ESCC. We found a positive association between higher serum selenium concentration and prevalence of ESD, an association contrary to our original hypothesis. Further work is needed to better understand the role of selenium in the etiology of ESCC in this region, and to develop effective ESCC prevention and control strategies.

Factors associated with the high prevalence of oesophageal cancer in Western Kenya: a review

Oesophageal carcinoma (OC) is highly prevalent in Western Kenya especially among the members of the Kalenjin community who reside in the Northern and Southern areas of the Rift Valley. Previous authors have suggested potential association of environmental and genetic risk factors with this high prevalence. The environmental factors that have been suggested include contamination of food by mycotoxins and/or pesticides, consumption of traditional alcohol (locally referred to “Busaa” and “Chan’gaa”), use of fermented milk (“Mursik”), poor diet, tobacco use and genetic predisposition. The aim of this paper is to critically examine the potential contribution of each of the factors that have been postulated to be associated with the high prevalence of the disease in order to establish the most likely cause. We have done this by analyzing the trends, characteristics and behaviours that are specifically unique in the region, and corroborated this with the available literature.

From our findings, the most plausible cause of the high incidence of OC among the Kalenjin community is mycotoxins, particularly fumonisins from the food chain resulting from poor handling of cereals; particularly maize combined with traditional alcohol laced with the toxins interacting synergistically with other high-risk factors such as dietary deficiencies associated alcoholism and viral infections, especially HPV. Urgent mitigating strategies should be developed in order to minimize the levels of mycotoxins in the food chain.

Is Clinical Research in Oesophageal Cancer in South Africa in Crisis? A Systematic Review

Oesophageal cancer (OC) is responsible for the second highest number of cancer-related deaths in South Africa (SA). Squamous cell carcinoma is the most prevalent type with an incidence of 46.7/100,000 and 19.2/100,000 for males and females. This is a systematic review of the clinical diagnosis and management of OC within the South African context. This protocol was registered with the International Prospective Register of Systematic Reviews (PROSPERO) (registration number CRD42016034053) with adherence to PRISMA guidelines. An online search was performed using MEDLINE, EBSCOHost and PubMed. Eligibility criteria for articles included published, original peer-reviewed research addressing clinical management of oesophageal cancer in South Africa. Review articles, case reports, scientific letters and studies published in languages other than English or Afrikaans were excluded. The research terms were 'etiology', 'human', 'esophageal cancer', 'esophageal carcinoma', 'oesophageal cancer', and 'oesophageal carcinoma', 'squamous cell carcinoma', 'Africa' and 'South Africa'. A total of 336 articles were identified. Of these, 146 were immediately excluded and a further 159 were excluded after review. A total of 31 appropriate articles, i.e. 9.2% of searched articles, were included. Thirteen articles addressed chemotherapy and/or radiotherapy, 9 oesophageal luminal therapy, 7 oesophageal surgery and 2 screening. OC research of in SA over the last two decades has mainly been in the form of reviews and opinion papers. Clinical research, auditing and prospectively analysing OC management and outcomes in SA hospitals are sorely needed and should be promoted by both healthcare workers and policy makers alike.

International cancer seminars: a focus on esophageal squamous cell carcinoma

The International Agency for Research on Cancer (IARC) and the US National Cancer Institute (NCI) have initiated a series of cancer-focused seminars [Scelo G, Hofmann JN, Banks RE et al. International cancer seminars: a focus on kidney cancer. Ann Oncol 2016; 27(8): 1382-1385]. In this, the second seminar, IARC and NCI convened a workshop in order to examine the state of the current science on esophageal squamous cell carcinoma etiology, genetics, early detection, treatment, and palliation, was reviewed to identify the most critical open research questions. The results of these discussions were summarized by formulating a series of 'difficult questions', which should inform and prioritize future research efforts.

Three-year cancer incidence in Blantyre, Malawi (2008-2010)

In this paper, we present incidence rates of different cancers calculated for the population of Blantyre, Malawi for the period 2008-2010, using data from the Malawi Cancer Registry. Active methods were used for case finding, with standard checks for accuracy and validity performed in CanReg 4. During this 3-year period, a total of 3,711 cases were registered comprising 1,643 men (an estimated age-standardized incidence rate (ASR) of 169.8 per 100,000) and 2,068 women (ASR 238.7 per 105 ). Kaposi sarcoma (KS) was the most common cancer in men (40.5% of all cancers in men; ASR 54.0 per 105 ) while cervical cancer was the commonest in women (33.3%; ASR 88.6 per 105 ). The incidence rates for esophageal cancer remain one of the highest in the world (ASR 30.9 per 100,000 in men, 22.1 per 100,000 in women). Incidence of cancer of the prostate is relatively low in Blantyre (5.1%; ASR 16.4 per 105 ), compared with elsewhere in Africa. In childhood, the cancer spectrum is dominated by Burkitt lymphoma (32.5% ASR 90.9 per 106 ) followed by Wilms tumor (11.3%; ASR 35.9 per 106 ) and pediatric KS (11.0%; ASR 31.1 per 106 ). The overall percentage of cases with histological verification was 47.5%, a slight improvement from 42.4% in late 1990s also indicating successful case finding outside laboratories.

Esophageal cancer in Kenya

Kenya belongs to a high incidence region known as Africa's esophageal cancer (EC) corridor. It has one of the highest incidence rates of EC worldwide, but research on EC in Kenya has gone highly unnoticed. EC in Kenya is unique in its high percentage of young cases (< 30 years of age). In this review, we show the current status of EC in the country. We mainly focus on significant risk factors such as alcohol drinking, genetic factors, malnutrition and hot food/drink. Future directions in the study and prevention of EC in Kenya are also discussed.

Characteristics of Esophageal Cancer Cases in Tanzania

Purpose

Age-standardized incidence rates for esophageal cancer (EC) in East Africa have been reported as disproportionately high compared with the worldwide incidence of nine per 100,000 population. This study aimed to characterize EC cases seen at Muhimbili National Hospital and Ocean Road Cancer Institute in Dar es Salaam, Tanzania.

Methods

Demographic, clinical, and treatment variables were abstracted from charts of patients who received care for a diagnosis of EC at one or both institutions between 2011 and 2013. Categorical data were summarized as frequency counts and percentages. Continuous data were presented as medians and ranges. To compare men and women, Pearson’s χ² and two-sample t tests were applied.

Results

Seven hundred thirty-eight unique cases of EC were identified, of whom 68% were men and the median age was 60 years (range, 19 to 95 years). Notably, 93 cases (13%) were ≤ 40 years old at diagnosis. Squamous cell carcinoma was the dominant histology, comprising 90% of cases with documented histopathology. However, 34% of cases with a diagnosis of EC were not pathologically confirmed. The stage was documented as locoregional in 4% of cases, locally advanced in 20% of cases, metastatic in 14% of cases, and unknown in 63% of cases. Of 430 patients who received treatment at Ocean Road Cancer Institute, 76% were treated with radiation, 44% were treated with chemotherapy, 3% underwent a cancer-related surgical procedure, and 10% of cases received no cancer-directed therapy. The median overall survival for all patients was 6.9 months (95% CI, 5.0 to 12.8), regardless of stage at presentation.

Conclusion

Between 2011 and 2013, cases of EC represented a large clinical burden at both institutions.

Clinical significance of serum cathepsin B and cystatin C levels and their ratio in the prognosis of patients with esophageal cancer

OBJECTIVE

The main purpose of this study was to analyze the serum cathepsin B (CTSB) and cystatin C (CysC) levels in patients with esophageal carcinoma and their correlation with the clinical indices and prognosis.

METHODS

The serum levels of CTSB and CysC from 56 patients with esophageal carcinoma and 30 healthy donors were determined preoperatively by using enzyme-linked immunosor-bent assay. The correlation between CTSB and CysC was evaluated by Spearman correlation coefficient test. Kaplan-Meier survival curves were plotted, while the survival rates were compared using the log-rank test. Univariate and multivariate analyses of prognostic factors for survival were performed using the Cox proportional hazard regression model with a 95% confidence interval.

RESULTS

CTSB (38.35±4.3 ng/mL) and CysC (703.96±23.6 ng/mL) levels were significantly higher in the sera of the patients than in controls. A significant correlation was observed between CTSB and CysC (r=0.754, P<0.001). The levels of CTSB and CysC/CTSB in the patient serum significantly correlated with the T status. CysC/CTSB ratio was also found to be significantly correlated with lymph node metastasis. None of the parameters were observed to be related to CysC, including age, gender, pathologic type, tumor differentiation and tumor invasion depth. Kaplan-Meier analysis showed that patients with higher levels of CysC/CTSB and negative lymph node metastasis experienced significantly longer overall survival time, whereas patients with higher CSTB levels tended to live shorter, although the difference was not statistically significant (P=0.081).

CONCLUSION

Serum CTSB and CysC levels are of diagnostic significance in esophageal cancer. The ratio of serum CysC/CTSB is prognostic for the survival of esophageal carcinoma patients.

Effects of irradiation on radioresistance, HOTAIR and epithelial-mesenchymal transition/cancer stem cell marker expression in esophageal squamous cell carcinoma

Radiotherapy is a common therapeutic strategy used to treat esophageal squamous cell carcinoma (ESCC). However, tumor cells often develop radioresistance, thereby reducing treatment efficacy. Here, we aimed to identify the mechanisms through which ESCC cells develop radioresistance and identify associated biomarkers. Eca109 cells were exposed to repeated radiation at 2 Gy/fraction for a total dose of 60 Gy (Eca109R60/2Gy cells). MTT and colony formation assays were performed to measure cell proliferation and compare the radiation biology parameters of Eca109 and Eca109R60/2Gy cells. Cell cycle distributions and apoptosis were assessed by flow cytometry. Reverse transcription-quantitative polymerase chain reaction and western blotting were employed to analyze the expression of HOX transcript antisense RNA (HOTAIR), in addition to biomarkers of the epithelial-mesenchymal transition (EMT) and cancer stem cells (CSCs). Eca109R60/2Gy cells exhibited increased cell proliferation and clone formation, with significantly higher radiobiological parameters compared with the parental Eca109 cells. The Eca109R60/2Gy cells also exhibited significantly decreased accumulation in G₂ phase and increased accumulation in S phase. Additionally, the apoptosis rate was significantly lower in Eca109R60/2Gy cells than in parental Eca109 cells. Finally, HOTAIR expression levels and SNAI1 and β-catenin mRNA and protein expression levels were significantly higher, whereas E-cadherin levels were significantly lower in Eca109R60/2Gy cells than in Eca109 cells. Therefore, our findings demonstrated that radioresistance was affected by the expression of HOTAIR and biomarkers of the EMT and CSCs.

Cancer risks in Nairobi (2000-2014) by ethnic group

We investigated the ethnic differences in the risk of several cancers in the population of Nairobi, Kenya, using data from the Nairobi Cancer Registry. The registry records the variable "Tribe" for each case, a categorisation that includes, as well as 22 tribal groups, categories for Kenyans of European and of Asian origin, and non-Kenyan Africans. Tribes included in the final analysis were Kikuyu, Kamba, Kisii, Kalenjin, Luo, Luhya, Somalis, Asians, non-Kenyans, Caucasians, Other tribes and unknown. The largest group was taken as the reference category for the calculation of odds ratios; this was African Kenyans (for comparisons by race), and Kikuyus (the tribe with the largest numbers of cancer registrations (38% of the total)) for comparisons between the Kenyan tribes. P-values are obtained from the Wald test. Cancers that were more common among the white population than in black Kenyans were skin cancers and cancers of the bladder, while cancers that are more common in Kenyan Asians include colorectal, lung, breast, ovary, corpus uteri and non-Hodgkin lymphoma. Cancers that were less common among Asians and Caucasians were oesophagus, stomach and cervix cancer. Within the African population, there were marked differences in cancer risk by tribe. Among the tribes of Bantu ethnicity, the Kamba had higher risks of melanoma, Kaposi sarcoma, liver and cervix cancer, and lower risks of oesophagus, stomach, corpus uteri and nervous system cancers. Luo and Luhya had much higher odds of Kaposi sarcoma and Burkitt lymphoma.

Informing etiologic research priorities for squamous cell esophageal cancer in Africa: A review of setting-specific exposures to known and putative risk factors

Esophageal squamous cell carcinoma (ESCC) is one of the most common cancers in most Eastern and Southern African countries, but its etiology has been understudied to date. To inform its research agenda, we undertook a review to identify, of the ESCC risk factors which have been established or strongly suggested worldwide, those with a high prevalence or high exposure levels in any ESCC-affected African setting and the sources thereof. We found that for almost all ESCC risk factors known to date, including tobacco, alcohol, hot beverage consumption, nitrosamines and both inhaled and ingested PAHs, there is evidence of population groups with raised exposures, the sources of which vary greatly between cultures across the ESCC corridor. Research encompassing these risk factors is warranted and is likely to identify primary prevention strategies.

Long-term outcomes of endoscopic multiband mucosectomy for early esophageal squamous cell neoplasia: a retrospective, single-center study

BACKGROUND AND AIMS

Endoscopic multiband mucosectomy (EMBM) has been used to treat early Barrett's esophagus and esophagogastric junction neoplasia, yet it is seldom reported for the treatment of early esophageal squamous cell neoplasia. Here we retrospectively evaluated the feasibility, safety, and efficacy of EMBM for early esophageal squamous cell neoplasia.

METHODS

A total of 125 patients were included in the study. Lesions were delineated using electrocoagulation and resected using the EMBM technique. The primary outcomes were local recurrence and adverse events. Secondary outcomes were histology of the endoscopic resection specimens, specimen area, and speed of resection. All patients were followed up endoscopically.

RESULTS

There were 135 esophageal lesions, of which 40 were pathologically diagnosed as low-grade intraepithelial neoplasia, 57 as high-grade intraepithelial neoplasia, 34 as early esophageal cancer, and 4 as squamous epithelium without neoplasia. No severe adverse events were observed, except for 1 perforation, which was treated by application of clips. The median follow-up was 27.75 months. Three patients had local recurrence and were endoscopically treated again. Local recurrence rate was 2.4% (3/125). No deaths occurred during the follow-up. All specimens were visible with a dividing rule, and the mean specimen area was 4.63 cm². Mean operation time was 31.2 ± 17.4 minutes. Mean speed of resection was 6.74 min/cm².

CONCLUSIONS

EMBM seems to be effective and safe for patients with early esophageal squamous cell neoplasia. The long-term recurrence rate is low.

Obesity and cancer: An update of the global impact

In view of the growing global obesity epidemic, this paper reviews the relation between recent trends in body mass index (BMI) and the changing profile of cancer worldwide. By examining seven selected countries, each representing a world region, a pattern of increasing BMI with region and gender-specific diversity is noted: increasing levels of BMI were most pronounced in the Middle East (Saudi Arabia), rather modest in Eastern Asia (India) and generally more rapid in females than in males. This observation translates into a disproportionate distribution of cancer attributable to high levels of BMI, ranging by sex from 4-9% in Saudi Arabia and from 0.2-1.2% in India. Overweight and obesity may also influence cancer outcomes, and hence have a varying impact on cancer survival and death in different world regions. Future challenges in cancer studies exploring the association with overweight and obesity concern the measurement of adiposity and its potentially cumulative effect over the life course. Given the limitations of BMI as an imperfect measure of body fatness, routine anthropometric data collection needs to be extended to develop more informative measures, such as waist circumference in settings where the gold standard tools remain unaffordable. Furthermore, questions surrounding the dose-response and timing of obesity and their associations with cancer remain to be answered. Improved surveillance of health risk factors including obesity as well as the scale and profile of cancer in every country of the world is urgently needed. This will enable the design of cost-effective actions to curb the growing burden of cancer related to excess body weight.

Black-white differences in cancer risk in Harare, Zimbabwe, during 1991-2010

Data from 20 years of cancer registration in Harare (Zimbabwe) are used to investigate the risk of cancer in the white population of the city (of European origin), relative to that in blacks (of African origin). In the absence of information on the respective populations-at-risk, we calculated odds of each major cancer among all cancers, and took the odds ratios of whites to blacks. Some major differences reflect obvious phenotypic differences (the very high incidence of skin cancer-melanoma and nonmelanoma--in the white population), whereas others (high rates of liver cancer, Kaposi sarcoma and conjunctival cancers in blacks) are the result of differences in exposure to infectious agents. Of particular interest are cancers related to lifestyle factors, and how the differences in risk are changing over time, as a result of evolving lifestyles. Thus, the high risk of cancers of the esophagus and cervix uteri in blacks (relative to whites) and colorectal cancers in whites show little change over time. Conversely, the odds of breast cancer, on average four times higher in whites than blacks, has shown a significant decrease in the differential over time. Cancer of the prostate, with the odds initially (1991-1997) 15% higher in whites had become 33% higher in blacks by 2004-2010.

The incidence and mortality of esophageal cancer and their relationship to development in Asia

BACKGROUND

Esophageal cancer is the most common cancer in less developed countries. It is necessary to understand epidemiology of the cancer for planning. The aim of this study was to evaluate the incidence and mortality of esophageal cancer, and its relationship with Human Development Index (HDI) and its components in Asia in 2012.

METHODS

This study was an Ecological study, which conducted based on GLOBOCAN project of WHO for Asian counters. We assess the correlation between standardized incidence rates (SIR) and standardized mortality rates (SMR) of esophageal cancer with HDI and its components with using of SPSS18.

RESULTS

A total of 337,698 incidence (70.33% were males and 29.87% females. Sex ratio was 2.37) and 296,734 death (69.45% in men and 30.54% in women. The sex ratio was 2.27) esophageal cancer was recorded in Asian countries in 2012. Five countries with the highest SIR and SMR of esophageal cancer were Turkmenistan, Mongolia and Tajikistan, Bangladesh and China respectively. Correlation between HDI and SIR was -0.211 (P=0.159), in men -0.175 (P=0.244) and in women -0.231 (P=0.123). Also between HDI and SMR -0.250 (P=0.094) in men -0.226 (P=0.131) and in women -0.251 (P=0.037).

CONCLUSIONS

The incidence of esophageal cancer is more in less developed and developing countries. Statistically significant correlation was not found between standardized incidence and mortality rates of esophageal cancer, and HDI and its dimensions, except for life expectancy at birth.