Stem cell transplant; (Panel 1): Drawing of stem cells being removed from a patient or donor. Blood is collected from a vein in the arm and flows through a machine that removes the stem cells; the remaining blood is returned to a vein in the other arm. (Panel 2): Drawing of a health care provider giving a patient treatment to kill blood-forming cells. Chemotherapy is given to the patient through a catheter in the chest. (Panel 3): Drawing of stem cells being given to the patient through a catheter in the chest.