A 52-year-old man from Delhi presents with a 2-month history of progressive weakness, bleeding gums, and recurrent infections. On examination, he has pallor, petechiae, and lymphadenopathy. Laboratory findings: Hemoglobin 6.8 g/dL, WBC 18,500/μL (with 35% blasts), platelets 32,000/μL. Bone marrow aspiration shows 42% blasts with Auer rods. Cytochemistry: MPO positive. What is the most appropriate next step in management?