Abstract:
ABSTRACT: Chronic myeloid leukemia (CML) is a myeloproliferative neoplasm (MPN) of hematopoietic stem cells characterized by the presence of the Philadelphia (Ph) chromosome (t (9;22) (q34.1;qll.2), in which granulocytes are the major proliferative component. Atypical presentations of chronic phase CML reported include extreme thrombocytosis with or without leukocytosis, marked megakaryocytic proliferation or significant marrow fibrosis. We describe a middle-aged woman who presented with nonspecific leg pain and abnormal FBC parameters. Moderate leukocytosis (WBC 55 x 103/ pl), mild anemia and marked thrombocytosis (1,615 xl03/pl) were noted without clinical or laboratory features of ongoing infection or inflammation. Clinical examination revealed mild pallor only. A prominent spleen was noted ultrasonically (13.5 cm). A leucoerythroblastic blood picture was seen with moderate neutrophil leukocytosis, tear drop poikilocytes and one percent blast cells. No characteristic myelocytes and neutrophil peaks were present, and dysplasia was absent. Mild eosinophilia was observed however basophilia was absent. Platelets were markedly increased with anisocytosis. An underlying MPN suspected. JAK2V617 F mutation was absent and BCR-ABL (transcript type- b3a2) mutation detected. Her bone marrow biopsy revealed markedly hyper- cellular fragments with suppressed erythropoiesis, markedly hypercellular granulopoiesis (blasts <5%) with prominent eosinophil precursors. Megakaryocyte numbers were markedly increased with numerous micro megakaryocytes. The trephine biopsy displayed a few loose clusters of megakaryocytes. A marked background fibrosis noted (Grade (3/3). The diagnosis of chronic phase- CML was made. She was commenced on Imatinib 400mg daily and she achieved and maintained all the desired milestones since diagnosis.
