The Role of Microbiome and Probiotics in Chemo-Radiotherapy-Induced Diarrhea: A Narrative Review of the Current Evidence

BackgroundIn this article, we review the most recent research on probiotics effects on diarrhea in both human and animal models of the condition along with the therapeutic potential of these compounds based on their findings.Recent FindingsNearly 50%-80% of cancer patients experience chemotherapy-induced diarrhea (CID), serious gastrointestinal toxicity of chemotherapeutic and radiation regimens that leads to prolonged hospitalizations, cardiovascular problems, electrolyte imbalances, disruptions in cancer treatment, poor cancer prognosis, and death. CID is typically categorized as osmotic diarrhea. The depletion of colonic crypts and villi by radiotherapy and chemotherapy agents interferes with the absorptive function of the intestine, thereby decreasing the absorption of chloride and releasing water into the intestinal lumen. Probiotic supplements have been found to be able to reverse the intestinal damage caused by chemo-radiation therapy by promoting the growth of crypt and villi and reducing inflammatory pathways. In addition, they support the modulation of immunological and angiogenesis responses in the gut as well as the metabolism of certain digestive enzymes by altering the gut microbiota.ConclusionBeyond the benefits of probiotics, additional clinical research is required to clarify the most effective strain combinations and dosages for preventing chemotherapy and radiotherapy diarrhea.