INTENSIFICATION THERAPY: Patients in complete remission receive intensification therapy. Therapy begins no earlier than 2 weeks and no later than 4 weeks after complete remission is attained. Patients are stratified according to cytogenetics (favorable [t(8;21)(q22;q22) or inv(16)(p13;q22) or t(16;16)(p13;q22)] vs unfavorable [all other karyotypes]).