SAGES Magazine

THE SOUTH AFRICAN GASTROENTEROLOGY REVIEW 2021 | VOLUME 19 | ISSUE 2 | 5 REVIEW Oesophageal cancer in Sub-Saharan Africa: a Kenyan perspective MM Mwachiro 1 , RE White 2 , MD Topazian 2 , SR Thomson 3 Department of Surgery, Tenwek Hospital, Bomet, Kenya 1 Department of Surgery, Alpert Medical School of Brown University, Providence, RI, USA 2 Division of Gastroenterology and Hepatology, Mayo Clinic, Rochester, MN, USA 3 Emeritus Professor Division of Medical Gastroenterology, Department of Medicine, University of Cape Town, South Africa 4 Introduction Oesophageal cancer is the 8 th most common cancer globally with 604100 new cases and 544076 new deaths recorded in 2020. 1 The most common variants are oesophageal, adenocarcinoma (OAC) and squamous cell carcinoma (OSCC). 2 The latter is the main variant in Africa and the Far East particularly China and Japan. Trends in higher income countries (HIC’s) show a decline in incidence OSCC and an increase in OAC. 3, There is regional variation in incidence of OSCC, male to female ratios are similar in northern African countries but countries in the western, middle, eastern and southern Africa have a male predominance. 4,5 Risk factors for OC include smoking, alcohol, smoke exposure from wood or charcoal, poor oral health, consuming red meat, low socio- economic status and nutritional deficiencies like selenium. Risk factors that are specific for OAC include gastroesophageal reflux disease, obesity and Barrett’s oesophagus. 5-7 The highest age standardized rates for OSCC in the world are also found in Africa. Figure 1 depicts the global incidence rates. In comparison to HICs, survival data from the continent is very poor with the number of new cases and deaths being almost the same. 1,4 The factors that contribute to poor outcomes are interlinked and relate to disease stage at presentation and infrastructural challenges due to socio-economic inequalities. Progressive dysphagia is the commonest symptom and contributes to poor nutritional status that has been associated with poor outcomes and increased mortality rates. 6, 9 Poor access to and resource availability at health care facilities, are due to, inadequate referral pathways and transportation networks and scarce endoscopy, radiology, radiotherapy and surgery services. Endoscopy services are sparse especially in rural areas leading to delays occasioned by referrals. 6,10 Access to radiotherapy which has a potential curative as well as palliative role in management is an extreme challenge across the continent. 11 Early oesophageal cancer The care for OSCC is dependent on the stage at presentation. Correspondence Michael Mwachiro email: deche2002@yahoo.com Figure 1. Oesophagael Cancer: age standardised incidence rates per 100 000 Diagnostic work up is currently based on guidelines and consensus statements including the National Comprehensive Cancer Network guidelines. 12 These have also been harmornized for Sub-Saharan Africa with provision to use what is locally available. In general a thorough history, physician examination, and endoscopic evaluation with biopsy are the key initial component. CT scanning is also important to accurately stage the disease. Early esophageal disease is not a common occurrence in the African context. This is partly due to the nature of disease progression which is intraluminal and by the time dysphagia occurs the disease is usually advanced. Oesophageal squamous dysplasia is the precursor lesion for oesophageal squamous cell carcinoma. 13 Prior research in high incidence areas illustrated that the dysplastic lesions can be easily demonstrated using Lugol’s iodine chromoendoscopy (LCE). 13 Dysplastic areas on the oesophagus do not take up iodine and are unstained. LCE increases both the yield and sensitivity to detect unstained lesions (USLs). 13 LCE is feasible in our setup. The team at Tenwek Hospital has initiated a Surgical Treatment Early Detection Palliation (STEP) programme and from its catchment area shown in Figure 2 conducted a screening study using LCE. This study reported a high-grade dysplasia (HGD) rate of 2.9% and overall dysplasia rate of 14% in an asymptomatic population. 14 LCE only requires endoscopy and provision of Lugol’s Iodine which is easily available making its adaptable to local resource constrained environments. This HGD prevalence rate was comparable to other high-risk areas like China and Iran. 15,16 However, due to the differences in population sizes, screening at population level will not have a high return rate in Africa. Screening in high-risk areas has