Discuss Fecal Microbiota Transplant(FMT) in hematologic and oncologic diseases. Section to be covered include Continued use of antibiotics and immunosuppresants agents/chemotherapies (advantage of capsule-delivered FMT that can be used for maintenance), risks for bacteremia and fatal septicemia, especially in neutropenic patients (cite the two cases reported in NEJM from boston , due to donor-derived ESBL), FMT in Sickle cell anemia patients to fortify intestinal barrier and reduce frequency of painful crisis, Same donor combined FMT and hematopoietic stem cell transplant to reduce the risks for gut graft vs host disease since donor lymphocyte are already tolerant to the donor intestinal microbial community and Selective microbial transplant instead of FMT eg the use of akkermansia muciniphila, but over population increases the risks of metastasis in mucin-producing cancers, as demonstrated in mouse model of breast cancer.