The purpose of autologous stem cell transplantation is to facilitate the recovery of the blood-forming system (hematopoietic system) after high-dose cancer treatment. While intensive chemotherapy or radiation therapy is necessary for some types of cancer, these treatments can severely damage the patient's healthy stem cells and immune system. To mitigate this risk, the patient's own (autologous) stem cells are collected and cryopreserved before high-dose treatment begins. After the intensive treatment is completed, these stored stem cells are returned to the patient; this process is generally referred to as stem cell rescue. This procedure is commonly used to treat diseases such as lymphoma, multiple myeloma in adults, and some solid tumors in children. A significant advantage of autologous transplantation is the extremely low risk of graft rejection or graft-versus-host disease (GVHD), as the patient receives their own cells. Consequently, autologous stem cell transplantation is generally considered safer than allogeneic transplants.