Fig. 1

A Patient 1 was diagnosed with AML in 2016 and treated with standard induction chemotherapy of cytarabine arabinoside, and daunorubicin (AD 7 + 3), and further re-induction chemotherapy of cytarabine and idarubicin (AI 7 + 3). No consolidation chemotherapy was performed due to the patient’s refusal. Unfortunately, the patient’s disease relapsed as acute undifferentiated leukemia. She was treated with salvage chemotherapy of fludarabine, and cytosine arabinoside, and G-CSF (FLAG) and achieved complete remission (CR). She was treated with one cycle of intermediate-dose Ara-C consolidation (IDAC). Then she underwent an allogeneic peripheral blood stem cell transplant (Allo-PBSCT). After approximately one month, she had a tendency to sleep and deterioration of consciousness was accelerated. Polymorphonuclear (PMN) leukocyte dominant pleocytosis had developed. Under the clinical impression of CNS-GVHD, methylprednisolone (mPD, 120 mg), intravenous immunoglobulin (IVIG), and intrathecal hydrocortisone therapy were implemented. However, she showed drowsy mentality acutely and died of respiratory failure. It was only three months after she began to develop a tendency to sleep. B Patient 2 was diagnosed with myelodysplastic syndrome (MDS) and was treated with three cycles of azacytidine for 3 months. He received allogeneic peripheral blood stem cell transplant (Allo PBSCT). Approximately one month later, he developed motor dysfunction (general weakness, gait disability, and fecal and urinary incontinence). Then sleep tendency and disorientation developed. Under the clinical impression of CNS-GVHD, methylprednisolone (mPD) pulse plus IVIG, rituximab and ruxolitinib were implemented. These symptoms improved temporarily but got worse. He was given tacrolimus and mycophenolate mofetil (MMF) instead of mPd pulse and IVIG. However, the patient’s condition deteriorated rapidly, and within three months after dyskinesia, he died of pneumonia, septic shock, disseminated intravascular coagulopathy (DIC), and multiorgan failure