Risk Factors for Esophageal Cancer in a High-incidence Area of Malawi

Abstract

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. 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 (HIV), herpes simplex virus (HSV), cytomegalovirus (CMV), Epstein–Barr virus (EBV), varicella-zoster virus (VZV), and Helicobacter pylori were determined serologically. Fisher’s exact test was used for nominal variables and the Mann–Whitney U test was used for continuous variables. Binary linear regression was performed with variables that were significant in the Fisher and Mann–Whitney tests.Results The tumor and control groups comprised 157 and 70 patients, respectively. Patients with tumors were significantly older than controls (P < 0.001). 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 agent. In logistic regression analysis, age [odds ratio (OR), 1.042; 95% confidence interval (CI), 1.019–1.066; P < 0.001] and hot food and tea consumption (OR, 2.331; 95% CI, 1.167–4.656; P = 0.016) were significant.Conclusions Apart from alcohol consumption and smoking, the consumption of hot food or tea and smoked fish are associated with EC in Malawi.