Gut Microbiome: The New Frontier in Cancer Care
As a specialist in blood cancers like leukemia, Dr. Marcel van den Brink recognized in the early 1990s that aggressive chemotherapy and antibiotics used to rebuild patients' immune systems could cause 'collateral damage.' Now, research led by teams including his at City of Hope Cancer Center shows that the balance of gut bacteria is critical for the success of immunotherapy and stem cell transplants.
Microbiome and Immune System: A Tight Connection
Dr. Jay Bhattacharya, director of the U.S. National Institutes of Health, called recent findings 'mind-blowing.' A publication by the American Society of Clinical Oncology lists nearly 100 ongoing studies testing ways to manipulate the gut microbiome to help treat cancer.
Probiotics: From Chickens to Humans
Poultry and livestock farmers have long used probiotics to boost animal health. Now, a large National Cancer Institute-funded trial is testing the probiotic CBM588 (Clostridium butyricum) in kidney cancer patients. Early results show improved outcomes when combined with immunotherapy.
The Necessity of Antibiotic Stewardship
Dr. van den Brink emphasizes that 'the less damage you do to bacteria, the better off you are.' Overuse of broad-spectrum antibiotics can decimate the gut ecosystem, turning a diverse 'Amazon rainforest' of hundreds of bacterial strains into a single-species 'desert.' This leads to inflammation, diarrhea, and dangerous infections.
At the CHUM Microbiome Centre, Dr. Arielle Elkrief's team reduced antibiotic use in lung cancer patients from 20% to 5% before immunotherapy, following the 'first, do no harm' principle.
Looking Ahead
Research is ongoing, but scientists agree: protecting the gut microbiome protects the immune system. Personalized probiotics, dietary interventions, and precise antibiotic use may become standard in cancer care.