Esophageal Disease and the Role of the Microbiome - Chapter 7: Esophageal dysbiosis and esophageal squamous cell carcinoma

Although studies of esophageal squamous cell carcinoma (ESCC) and the upper aerodigestive microbiomes to date are exploratory in nature, it is increasingly apparent that these bacterial communities may play an important role in carcinogenesis and outcomes. Changes in esophageal microbial diversity and composition with ESCC may reflect underlying shifts in gene expression and carcinogen metabolism. Decreased intake of fruits and vegetables and poor oral health and hygiene are associated with increased risk of ESCC, likely mediated in part by accompanying microbiome alterations. Two oral pathogens, Porphyromonas gingivalis and Fusobacterium nucleatum, have been highlighted as possible key players in ESCC carcinogenesis and markers of prognosis. Studies are limited, however, because of sampling bias and primarily cross-sectional data. Additional experimental studies in both humans and animal models are needed to explore the role of microbiomes in the etiology and progression of ESCC.