This is a phase 3, open label, single arm, multi-center study in newly diagnosed ETP-ALL/LBL, T/M-MPAL and ALL/LBL patients who have myeloid or stem cell markers. The patients will receive decitabine combined with HAAG regimen in the induction treatment. The patients who respond to induction chemotherapy will undergo consolidation chemotherapy, and an optional allogeneic hematopoietic stem cell transplantation and post-transplantation maintenance treatment with decitabine according to patient's wishes.

