Table 1.

Clinical studies on specific bacteria and bacterial dysbiosis in esophageal cancer

Specific bacteria or bacterial dysbiosis	Findings (References)
Esophageal squamous dysplasia and squamous cell carcinoma
Bacterial dysbiosis	Lower microbial diversity in the esophagus was associated with the presence of esophageal squamous dysplasia (85). Lower microbial diversity in oral microbiota was associated with the presence of esophageal squamous cell carcinoma (86). The composition of the gastric mucosal microbiota differs in early stage esophageal squamous cell carcinoma and esophageal squamous dysplasia from the healthy esophagus (87).
Fusobacterium nucleatum	A high amount of Fusobacterium nucleatum was associated with shorter cancer-specific survival and overall survival in esophageal cancer, and the amount of Fusobacterium nucleatum correlated with tumor expression of the chemokine CCL20 (93).
Barrett’s esophagus and esophageal adenocarcinoma
Helicobacter pylori	Infection with CagA-positve strains of Helicobacter pylori was associated with decreased risk of esophageal adenocarcinoma (88, 89). Infection with Helicobacter pylori in the stomach was associated with decreased genomic instability in Barrett’s esophagus (90).
Escherichia coli	A high amount of Escherichia coli was associated with Barrett’s esophagus and esophageal adenocarcinoma and the activation of the Toll-like receptor signaling pathway (91).
Campylobacter concisus	A high amount of Campylobacter concisus was associated with increased expression of IL18 that was associated with carcinogenesis in Barrett’s esophagus (92).