Most of patients with acute myeloid leukemia (AML) are elder and have poor prognosis despite induction chemotherapy.The regimen of cytarabine(Ara-C), aclarubicin and G-CSF (CAG regimen ) has been widely used in China for the treatment of acute myeloid leukemia (AML). Strategies to reduce the toxicity associated with intensive chemotherapy include the attenuated doses of standard regimens and myeloid growth factors. Granulocyte colony-stimulating factor(G-CSF) is efective in the prophylaxis and management of chemotherapy-induced neutropenia，but requires daily administration because of its short half-life． Pegylated granulocyte colony-stimulating factor (PEG-G-CSF )is a long-acting reagent that permits less frequent injection．The project is undertaken by Qilu Hospital of Shandong University and other well-known hospitals in China.In order to report the efficacy and safety of PEG-G-CSF combined with Ara-C and aclarubicin for the treatment of Acute Myeloid Leukemia, compared to the regimen of Ara-C, aclarubicin and G-CSF (CAG ).

The Investigators are undertaking a parallel, multicentre, randomised open-label trial of newly diagnosed AML (not APL) patients in China. Participants are randomised selected to receive the regimen of Ara-C, aclarubicin and PEG-G-CSF , or the regimen of Ara-C, aclarubicin and G-CSF (CAG ).Platelet count, bleeding and other symptoms are evaluated before and after treatment. Adverse events are also recorded throughout the study.

Inclusion Criteria:

1. age 60 years and older, with an upper age limit of 75 years;
2. diagnosis of AML other than APL
3. Adequate hepatic and renal function (aspartate aminotransferase [AST], alanine aminotransferase [ALT], bilirubin and creatinine < 2.5 x upper normal limit).

Exclusion Criteria:

1. History of severe congestive heart failure or other cardiac disease that contraindicates the use of anthracyclines, including idarubicin
2. Use of recreational drugs or history of drug addiction, within the prior 6 months
3. Known history of positive hepatitis B surface antigens or hepatitis C virus (HCV) antibodies
4. Patients with documented cases of human immunodeficiency virus (HIV)