Abstract: As a prevalent malignant neoplasm among the elderly,colorectal cancer(CRC)poses a severe threat to public health.Many elderly CRC patients are intolerant to the side effects of chemoradiotherapy,anesthetic hazards and postoperative rehabilitation complications,underscoring the urgent clinical need for well-tolerated and gentle treatment options.Given the close pathophysiological correlation between gut microbiota and colorectal cancer,this paper reviews existing literature to systematically elaborate the mechanisms whereby distinct gut microbial species mediate CRC initiation and progression.Current evidence indicates that targeted gut microbiota modulation can serve as an interventional strategy against CRC.Such interventions include stabilizing the abundance and homeostasis of beneficial intestinal bacteria while suppressing the pathogenic damage induced by harmful strains,as well as sustaining physiological equilibrium of the gut microbiome to preserve its regular secretory function and production of health-promoting metabolites for intestinal protection.These findings suggest that harnessing the physiological properties of gut microbiota may facilitate the development of a gentle anti-cancer therapy tailored specifically for elderly patients with colorectal cancer.

Key words: colorectal cancer, gut microbiota, microbiota metabolite, clinical treatment