A previous preliminary study performed at Vanderbilt University with funding from the Leukemia Society of America demonstrated that the response of leukemia cells in vitro to the chemotherapeutic agent idarubicin in the microculture kinetic assay for apoptosis (MiCK assay) predicted survival in patients with newly diagnosed acute myeloid leukemia (AML). In this previous study, achievement of complete response (CR) to induction therapy with idarubicin and cytarabine was used as the clinical indicator for determining whether leukemia specimens taken prior to treatment were sensitive or not sensitive in the MiCK assay. This group of patients has been followed for 7 years and their long term survival rates show that their responses in the MiCK assay to idarubicin but not cytarabine predict survival. In the present proposal a separate group of patients with newly diagnosed AML will be recruited to provide leukemia cell samples that will be used to establish criteria for sensitivity and non-sensitivity to idarubicin and cytarabine in the MiCK assay. The achievement of CR will be used to determine in vitro sensitivity as it was done in the previous study. With the in vitro sensitivities as determined in this proposed study, the long term survivals of patients in the previous study will be analyzed prospectively.