A Peculiar Manifestation of Chronic Myelogenous Leukemia in Lymphoid Blast Crisis

A 61-year-old man with a history of factor V Leiden mutation, hypothyroidism, and transient ischemic attacks presented to his physician's office but could not recall the reason for his visit. Initial laboratory test results showed a slight leukocytosis with slight basophilia; neuro-immunologic, infectious, and metabolic work-up was unrevealing. Flow cytometry results showed atypical B lymphoblasts. Bone marrow biopsy results revealed a hypercellular bone marrow with CD10 staining lymphoblasts and Philadelphia chromosomal translocation. Hematologic malignancy fusion panel results revealed BCR/ABL1 fusion with p210 oncoprotein, establishing the diagnosis of chronic myelogenous leukemia in lymphoid blast crisis—a peculiar manifestation of a disease that usually manifests with significant leukocytosis.