The goal of this clinical trial is to learn if fecal microbiota transplantation can treat in Gastrointestinal cancer patients with chemotherapy / targeted gastrointestinal symptoms. The main question it aims to answer is: To evaluate the effect of fecal microbiota transplantation (FMT) on gastrointestinal tract in patients with gastrointestinal tumors.
Age ≥ 18 years, gender not restricted;
Estimated survival time ≥ 3 months;
Confirmed diagnosis of gastrointestinal tumors by pathological examination, including esophageal cancer, gastric cancer, colon cancer, rectal cancer, etc.;
TNM staging of cancer in patients is Stage IV;
Patients with major organ dysfunction or even failure, including but not limited to cardiac insufficiency or heart failure, renal insufficiency or renal failure, and hepatic insufficiency/hepatic failure;
Uncontrolled or severe infections;
Known history of psychotropic substance abuse, alcoholism, and drug abuse;
Patients with severe infections complicated with septicemia or sepsis;