Bone marrow transplantation or peripheral stem cell transplantation may also be used in cancer treatment. The transplant may be autologous (the person’s own cells that were saved earlier), allogeneic (cells donated by another person), or syngeneic (cells donated by an identical twin). Both BMT and PSCT provide the patient with healthy stem cells. These replace stem cells that have been damaged or destroyed by very high doses of chemotherapy and/or radiation treatment.