LAUSR

Abstract Intracranial myeloid sarcoma is a very rare disease with poor prognosis. We report a case of a 28-year-old male patient who was admitted with intense headache, vision disturbance and severe vomiting in June 2017. He had a history of neurosurgical tumor resection operation in April 2017, and the pathological diagnosis was intracranial myeloid sarcoma. Bone marrow aspirate and biopsy had been conducted in May 2017, which demonstrated 5.5% blasts expressing CD13, CD33, CD34, CD117 and MPO, and the cytogenetic analysis demonstrated t(8;21)(q22;q22), and molecular studies showed a positive RUNX1-RUNX1T1 rearrangement. The diagnosis of acute myeloid leukemia (AML) with t (8; 21) (q22; q22)/RUNX1-RUNX1T1 was made, however, the patient refused to receive any systemic chemotherapy. Emergency cranial CT demonstrated a circular hyperdense mass (54mm×37mm), which was surrounded by hypodense peritumoral edema in the left cerebellar hemisphere, and the density of the lesions was uniform and the margin was clear. Idarubicin (12mg/m2·d×3 days) combined with high-dose cytarabine (2g/m2 q12h×3 days) was initiated for emergency chemotherapy. All of the above symptoms disappeared at the end of chemotherapy. On the first day after chemotherapy, the cranial CT indicated that the cranial lesion was markedly reduced (20mm×15mm), and on the sixth day after chemotherapy, the lesion was completely disappeared. Currently, there are no clear guidelines for the treatment of intracranial myeloid sarcoma, and our treatment approaches could provide a reference for this disease with such emergency situation.