Snapshot A 62-year-old man presents to his primary care provider for an urgent care visit. He reports feeling very fatigued recently. He denies any change in bowel movements or any blood in his stool. On physical exam, he has mild splenomegaly. Blood tests come back with increased leukocytosis with neutrophilic dominance and increased basophils. Concerned, his primary care provider refers him to hematology-oncology. His peripheral smear shows myeloid cells. Introduction Also known as chronic myelogenous leukemia Clonal hematopoietic stem cell disorder Pathogenesis login to view 4 more bullets Epidemiology login to view 2 more bullets May transform into blast crisis login to view 1 more bullet Presentation Symptoms login to view 4 more bullets Physical exam login to view 1 more bullet Evaluation Complete blood count with differential login to view 4 more bullets ↓ leukocyte alkaline phosphatase login to view 1 more bullet Bone marrow aspirate and biopsy Cytogenetic analysis or FISH showing Philadelphia chromosome (most accurate) Differential Diagnosis Chronic myelomonocytic leukemia Chronic eosinophilic leukemia Primary myelofibrosis Acute myeloid leukemic Leukemoid reaction login to view 2 more bullets Treatment Medical management login to view 4 more bullets Surgical management login to view 3 more bullets Prognosis, Prevention, and Complications Prognosis login to view 2 more bullets Complications login to view 5 more bullets