Primary isolated central nervous system acute lymphoblastic leukemia with BCR-ABL1 rearrangement: A case report

BACKGROUND: BCR-ABL1 fusion gene is associated with a poor prognosis and a high incidence in central nervous system (CNS) leukemia. CNS invasion which detected at the initial diagnosis is commonly with bone marrow infiltration. It is uncommon for the leukemia cells to be located primarily in the CNS without bone marrow involvement. CASE SUMMARY: We here report the rare initial presentation of CNS-restricted BCR-ABL-positive acute lymphoblastic leukemia in a 30-year-old female patient who clinically manifested with leukemic meningitis, with no involvement in peripheral blood or bone marrow. Identification of abnormal phenotypes of blast cells, and BCR-ABL1 rearrangement in the cerebrospinal fluid alone established the diagnosis of primary CNS-isolated acute lymphocytic leukemia. The patient received a combination of intrathecal therapy and high-dose chemotherapy. But the benefits of the treatments were short-lived and she experienced recurrence. CONCLUSION: Flow cytometry in combination with molecular genetic analysis improved diagnostic accuracy. New approaches that may enhance the efficacy of the existing therapies and cure CNS leukemia are required.