ATO + ATRA: ATO 0.15 mg/kg days 1 to 5 and 8 to 12, and ATRA 45 mg/m2/d days 1 to 15, every 29 days. Administration of 9 cycles, and followed by ATRA 45 mg/m2/d during 15 days every 3 months until complete two years of maintenance.