Objective To compare the differences in fecal flora among patients with esophageal cancer,gastric cancer,or colorectal cancer and between patients with gastrointestinal tumors and healthy people.Methods The 16S rRNA method was used to analyze the differences in fecal flora among 13 patients with esophageal squamous cell carcinoma,23 patients with gastric cancer,6 patients with colorectal cancer,and 49 healthy persons.Results Bifidobacterium,Faecalibacterium prausnitzii,and Ruminococcus callidus were less abundant in the fecal flora of cancer patients than in those of healthy controls(all P<0.05).Some species of Firmicutes and Actinobacteria were significantly reduced in the feces of patients with esophageal cancer or gastric cancer than in healthy people(P<0.05),whereas others showed consistency with the intestinal cancer group.Anti-tumor treatment,antibiotics,and lactic acid could affect the fecal flora of cancer patients.Conclusion The gut microbiota compositions(mainly Firmicutes and Actinobacteria)and some specific bacteria species in the feces of patients with esophageal cancer and gastric cancer are similar to those in the feces of patients with intestinal cancer,suggesting these bacteria may be involved in the development of upper gastrointestinal tumors.
Keywords: cancer; gastrointestinal neoplasms; gut microbiome.