A new study from Italy has shown that gut microbiota transplants—also known as fecal microbiota transplantation (FMT)—may improve the success of immunotherapy in people with advanced kidney cancer. It focused on people with metastatic renal cell carcinoma (mRCC), a serious type of kidney cancer that has spread to other parts of the body. The gut microbiota has a strong influence on the immune system. The research team believed that changing the gut microbiota might help patients respond better to treatment. If confirmed, this could be a big step toward making cancer treatment more effective, personalized, and safer for people with advanced kidney cancer.