Role of Infectious Agents on Development of Esophageal Carcinomas

Comprising two primary histological subtypes, esophageal squamous cell carcinoma and esophageal adenocarcinoma, esophageal cancer remains among the most aggressive forms of human malignancy. Despite advances in our understanding of the genetic landscape of esophageal cancer, patient outcomes remain poor, suggesting that cell extrinsic factors may influence disease pathogenesis. Interest in defining roles for infectious agents in esophageal carcinogenesis is rapidly emerging as an increasing number of clinical studies have linked various pathogens with esophageal cancer. Here, we review the current literature characterizing bacterial, viral, fungal and parasitic pathogens in the esophagus in the context of homeostasis and carcinogenesis. We discuss global changes in the microbial composition of the esophagus and adjacent organs as they relate to esophageal cancer. We further provide a comprehensive overview of the relationship between specific pathogens, including Helicobacter pylori, Herpesviridae and Human Immunodeficiency Virus, and esophageal cancer.