RESUMEN
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 .
Asunto(s)
Neoplasias Esofágicas/terapia , Carcinoma de Células Escamosas de Esófago/terapia , Cuidados Paliativos/métodos , Adulto , África Oriental , Investigación sobre la Eficacia Comparativa , Femenino , Recursos en Salud/provisión & distribución , Humanos , Estudios Longitudinales , Masculino , Estudios Observacionales como Asunto , Estudios Prospectivos , Resultado del TratamientoRESUMEN
There are no studies of oral health in relation to esophageal cancer in Africa, or of Eastern Africa's endemic dental fluorosis, an irreversible enamel hypo-mineralization due to early-life excessive fluoride intake. During 2014-18, we conducted a case-control study of squamous cell esophageal cancer in Eldoret, western Kenya. Odds ratios (AORs (95% confidence intervals)) were adjusted for design factors, tobacco, alcohol, ethnicity, education, oral hygiene and missing/decayed teeth. Esophageal cancer cases (N = 430) had poorer oral health and hygiene than controls (N = 440). Compared to no dental fluorosis, moderate/severe fluorosis, which affected 44% of cases, had a crude OR of 20.8 (11.6, 37.4) and on full adjustment was associated with 9.4-fold (4.6, 19.1) increased risk, whilst mild fluorosis (43% of cases) had an AOR of 2.3 (1.3, 4.0). The prevalence of oral leukoplakia and tooth loss/decay increased with fluorosis severity, and increased cancer risks associated with moderate/severe fluorosis were particularly strong in individuals with more tooth loss/decay. Using a mswaki stick (AOR = 1.7 (1.0, 2.9)) rather than a commercial tooth brush and infrequent tooth brushing also independently increased risk. Geographic variations showed that areas of high esophageal cancer incidence and those of high groundwater fluoride levels have remarkably similar locations across Eastern Africa. In conclusion, poor oral health in combination with, or as a result of, high-altitude susceptibility to hydro-geologically influenced dental fluorosis may underlie the striking co-location of Africa's esophageal cancer corridor with the Rift Valley. The findings call for heightened research into primary prevention opportunities of this highly fatal but common cancer.
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Neoplasias Esofágicas/epidemiología , Carcinoma de Células Escamosas de Esófago/epidemiología , Fluorosis Dental/epidemiología , África/epidemiología , Estudios de Casos y Controles , Femenino , Humanos , Masculino , Persona de Mediana Edad , Salud Bucal/estadística & datos numéricos , PrevalenciaRESUMEN
Oesophageal squamous cell carcinoma (ESCC) has markedly high incidence rates in Kenya and much of East Africa, with a dire prognosis and poorly understood aetiology. Consumption of hot beverages-a probable carcinogen to humans-is associated with increased ESCC risk in other settings and is habitually practiced in Kenya. We conducted a case-control study in Eldoret, western Kenya between August 2013 and March 2018. Cases were patients with endoscopically confirmed oesophageal cancer whose histology did not rule out ESCC. Age and sex-matched controls were hospital visitors and hospital out and in-patients excluding those with digestive diseases. Odds ratios (ORs) and 95% confidence intervals (CIs) were estimated for self-reported drinking temperatures; consumption frequency; mouth burning frequency and hot porridge consumption using logistic regression models adjusted for potential confounders. Drinking temperature association with tumour sub-location was also investigated. The study included 430 cases and 440 controls. Drinkers of 'very hot' and 'hot' beverages (>95% tea) had a 3.7 (95% CI: 2.1-6.5) and 1.4-fold (1.0-2.0) ESCC risk, respectively compared to 'warm' drinkers. This trend was consistent in males, females, never and ever alcohol/tobacco and was stronger over than under age 50 years. The tumour sub-location distribution (upper/middle/lower oesophagus) did not differ by reported drinking temperature. Our study is the first comprehensive investigation in this setting to-date to observe a link between hot beverage consumption and ESCC in East Africa. These findings provide further evidence for the role of this potentially modifiable risk factor in ESCC aetiology.
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Bebidas/efectos adversos , Ingestión de Líquidos , Neoplasias Esofágicas/epidemiología , Carcinoma de Células Escamosas de Esófago/epidemiología , Calor/efectos adversos , Distribución por Edad , Anciano , Estudios de Casos y Controles , Neoplasias Esofágicas/etiología , Carcinoma de Células Escamosas de Esófago/etiología , Femenino , Humanos , Kenia/epidemiología , Masculino , Persona de Mediana Edad , Factores de Riesgo , Distribución por Sexo , Encuestas y Cuestionarios/estadística & datos numéricosRESUMEN
Squamous cell esophageal cancer is common throughout East Africa, but its etiology is poorly understood. We investigated the contribution of alcohol consumption to esophageal cancer in Kenya, based on a hospital-based case-control study conducted from 08/2013 to 03/2018 in Eldoret, western Kenya. Cases had an endoscopy-confirmed esophageal tumor whose histology did not rule out squamous cell carcinoma. Age and gender frequency-matched controls were recruited from hospital visitors/patients without digestive diseases. Logistic regression was used to calculate odds ratios (ORs) and their 95% confidence intervals (CI) adjusting for tobacco (type, intensity) and 6 other potential confounders. A total of 422 cases (65% male, mean at diagnosis 60 (SD 14) years) and 414 controls were included. ORs for ever-drinking were stronger in ever-tobacco users (9.0, 95% CI: 3.4, 23.8, with few tobacco users who were never drinkers) than in never-tobacco users (2.6, 95% CI: 1.6, 4.1). Risk increased linearly with number of drinks: OR for >6 compared to >0 to ≤2 drinks/day were 5.2 (2.4, 11.4) in ever-tobacco users and 2.1 (0.7, 4.4) in never-tobacco users. Although most ethanol came from low ethanol alcohols (busaa or beer), for the same ethanol intake, if a greater proportion came from the moonshine chang'aa, it was associated with a specific additional risk. The population attributable fraction for >2 drinks per day was 48% overall and highest in male tobacco users. Alcohol consumption, particularly of busaa and chang'aa, contributes to half of the esophageal cancer burden in western Kenya.
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Consumo de Bebidas Alcohólicas/epidemiología , Bebidas Alcohólicas/clasificación , Neoplasias Esofágicas/epidemiología , Carcinoma de Células Escamosas de Esófago/epidemiología , Anciano , Estudios de Casos y Controles , Femenino , Humanos , Kenia/epidemiología , Masculino , Persona de Mediana Edad , RiesgoRESUMEN
BACKGROUND: Case-control studies remain an important study design for aetiologic research on cancer, particularly when cohorts are not available. In addition to the potential biases inherent in this design, conducting fieldwork in settings with weak health care and information systems for cancer, such as in sub Saharan Africa, confer additional challenges which we present here with the aim to share experience to guide future studies. METHODS: We undertook a hospital-based case-control study of squamous cell esophageal cancer at the Moi Teaching and Referral Hospital in Eldoret, West Kenya. Cases were recruited at endoscopy and controls from hospital wards, age and gender frequency-matched to cases. Urine, toenails, blood and tumour biopsy were collected and a questionnaire administered. RESULTS: During this pilot phase, 143 cases and 155 controls were successfully recruited. Complete questionnaire data was obtained through e-data collection. Biospecimen collection was possible with support of an already existing equipped laboratory. We introduce changes made in the main study phase, including on expansion of the control groups to allow to consideration of selection bias. CONCLUSIONS: Extra attention and funding to train and monitor data quality and biospecimen collection and collaboration of a large group held together by strong leadership are essential. We recommend studies based on regional treatment centres with their more defined catchment areas rather than in the capital cities as referral routes in multi-level health care systems are severely attrition prone.
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Estudios de Casos y Controles , Métodos Epidemiológicos , Neoplasias Esofágicas/epidemiología , Carcinoma de Células Escamosas de Esófago/epidemiología , Países en Desarrollo , Femenino , Humanos , Kenia/epidemiología , Masculino , Proyectos Piloto , Proyectos de Investigación , Encuestas y CuestionariosRESUMEN
BACKGROUND: The Kenya National Blood Transfusion Service (KNBTS) is mandated to provide safe and sufficient blood and blood components for the country. In 2013, the KNBTS National Testing Laboratory and the six regional blood transfusion centres were enrolled in the Strengthening Laboratory Management Toward Accreditation (SLMTA) programme. The process was supported by Global Communities with funding from the United States Centers for Disease Control and Prevention. METHODS: The SLMTA implementation at KNBTS followed the standard three-workshop series, on-site mentorships and audits. Baseline, midterm and exit audits were conducted at the seven facilities, using a standard checklist to measure progress. Given that SLMTA was designed for clinical and public health laboratories, key stakeholders, guided by Global Communities, tailored SLMTA materials to address blood transfusion services, and oriented trainers, auditors and mentors on the same. RESULTS: The seven facilities moved from an average of zero stars at baseline to an average of three stars at the exit audit. The average baseline audit score was 38% (97 points), midterm 71% (183 points) and exit audit 79% (205 points). The Occurrence Management and Process Improvement quality system essential had the largest improvement (at 67 percentage points), from baseline to exit, whereas Facilities and Safety had the smallest improvement (at 31 percentage points). CONCLUSION: SLMTA can be an effective tool for preparing a blood transfusion service for accreditation. Key success factors included customising SLMTA to blood transfusion activities; sensitising trainers, mentors and auditors on operations of blood transfusion service; creating SLMTA champions in key departments; and integrating other blood transfusion-specific accreditation standards into SLMTA.
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Kenya is one of the high endemic zones for hepatitis B virus (HBV) infection. The consensuses on prevalence of the HBV genotypes and the existence of their variants have not been fully established in Kenya. Hence, there is a need to further monitor the diversity of HBV. This study aimed to extend the current molecular and epidemiological information about the geographical distribution of HBV genotypes and subgenotypes, as well as to describe the hepatitis B surface antigen (HBsAg) variants circulating in different Regional Blood Transfusion Centres of Kenya. A total of 32 HBsAg positive blood units from five different blood transfusion centers in Kenya were used in the study. The HBV DNA preS/S-gene was amplified and sequenced. Alignments of S gene were applied using reference sequence from GeneBank. Phylogenetic analysis was performed using the MEGAv4.0 software with the neighbor-joining and maximum composite likelihood methods. Twenty-one plasma samples (65.6%) were DNA positive and were successfully sequenced. Eighteen out of the twenty-one isolates (85.7%) belonged to subgenotype A1 Afro-Asian: six were from Nairobi, four from Kisumu, two from Embu, and three each from Eldoret and Mombasa. The other three strains (14.3%, 3/21) belonged to subgenotype D4 from Mombasa. The HBsAg mutations were detected in nine isolates (42.9%, 9/21). The HBV/A1 and HBV/D4 are dominant among blood donors in Kenya. This demonstrates that continuous monitoring of the HBV diversity would help reveal circulating genotypes and subgenotypes as well as mutants of clinical significance in Kenya.
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Antígenos de Superficie de la Hepatitis B/genética , Virus de la Hepatitis B/aislamiento & purificación , Hepatitis B/virología , Secuencia de Aminoácidos , Donantes de Sangre/estadística & datos numéricos , Genotipo , Hepatitis B/epidemiología , Antígenos de Superficie de la Hepatitis B/química , Virus de la Hepatitis B/química , Virus de la Hepatitis B/clasificación , Virus de la Hepatitis B/genética , Humanos , Kenia/epidemiología , Datos de Secuencia Molecular , Mutación , Filogenia , Alineación de SecuenciaRESUMEN
Endemic Burkitt lymphoma (eBL) is the most common childhood cancer in equatorial Africa and is linked to Epstein-Barr virus (EBV) and Plasmodium falciparum coinfections early in life. Epstein-Barr nuclear antigen 1 (EBNA1) is the sole viral latent antigen expressed in BL tumors. Loss of EBNA1-specific immune surveillance could allow eBL emergence. Therefore, EBNA1-specific T cell responses were analyzed by IFN-gamma ELISPOT in Kenyan children with eBL and compared to healthy children with divergent malaria exposure. Significantly fewer children with eBL, 16% (7/44) had EBNA1-specific IFN-gamma responses in contrast to healthy children living in a malaria holoendemic area or in an area with sporadic malaria transmission, 67% (40/60) and 72% (43/60) responders, respectively (p < 0.003). Children with eBL maintained IgG(1) dominated antibody responses to EBNA1 similar to healthy children suggesting a selective loss of IFN-gamma secreting EBNA1-specific T cells in the presence of intact humoral immunity. CD8(+) T cell responses to EBV lytic and latent antigens not expressed in the tumors were similarly robust in eBL patients compared to healthy children. In addition, CD4(+) T cell responses to a malaria protein, merozoite surface protein 1, were present in lymphoma patients. This study demonstrates a selective loss of EBNA1-specific T cell responses in children with eBL and suggests a potential immunotherapeutic target for this EBV-associated lymphoma.