|Inclusion Criteria:||1) Patients must have untreated AML, or high-risk MDS [refractory anemia with excess blasts, (RAEB), or RAEB "in transformation" (RAEB-t)] characterized by t(8;21), inv(16), or t(16;16).The presence of additional abnormalities is irrelevant.|
2) Age equal to or greater than 18 years (the safety of GO in patients <18 years is not determined and advantage of fludarabine, cytarabine, idarubicin-based regimen in CBF leukemias in children is not demonstrated).
3) Patients must provide written consent.
4) Because of the high possibility of CR in CBF leukemias, participants will not be excluded based on performance status.For patients with Eastern Co-operative Oncology Group (ECOG) performance status >/= to 3 the dosing schedule will be discussed with study chairman.
5) Patients with organ dysfunction will not be excluded from the study. For patients with evidence of organ dysfunction (creatininie >/= 1.5, cardiac ejection fraction </= 50%, total bilirubin >/=2 and AST/ALT >/= 3 times ULN, dose adjustments/omissions will be made.
6) Up to one cycle of prior induction therapy will be permitted to include patients in whom presence of "good-risk" cytogenetics was initially missed. If the patient is in remission from induction therapy, he/she will receive post-remission therapy. If the patient is not in remission then he/she will receive induction therapy.
7) Patients of child bearing potential should practice effective methods of contraception.