RATIONALE: Giving combination chemotherapy before a stem cell transplant helps stop the growth of cancer cells. It also helps stop the patient's immune system from rejecting the transplanted stem cells. When the healthy stem cells are infused into the patient they may help the patient's bone marrow make stem cells, red blood cells, white blood cells, and platelets. If the patient's stem cells are to be transplanted, the patient is also treated with a monoclonal antibody, such as gemtuzumab ozogamicin, to kill any remaining cancer cells or deliver cancer-killing substances to them without harming normal cells. It is not yet known whether combination chemotherapy is more effective with or without gemtuzumab ozogamicin followed by stem cell transplant in treating acute myeloid leukemia.