Immunophenotypic Differences in Cerebrospinal Fluid and Peripheral Blood Demonstrating Cancer Heterogenicity in Acute Myeloid Leukemia Patient

A diagnosis of acute myeloid leukemia involving the central nervous system (CNS) can be confirmed through cerebrospinal fluid (CSF) and serum flow cytometry. These two detection methods should demonstrate the same immunophenotype due to hematogenous dissemination. Here, we reported a 65-year-old male diagnosed with CNS leukemia with differing immunophenotypes between CSF and peripheral blood. This immunophenotypic shift may suggest leukemic migration within the blood-brain barrier. In addition, the case highlights the concept of leukemic heterogeneity and the importance of considering cancer heterogeneity when analyzing a tumor's genetic profile and selecting therapy for patients.