Leukostasis followed by hemorrhage complicating the initiation of chemotherapy in patients with acute myeloid leukemia and hyperleukocytosis - A clinicopathologic report of four cases

BACKGROUND. Pulmonary and cerebral leukostasis, or parenchymal hemorrhage i n these organs, are well-known early complications developing in patients w ith acute myeloid leukemia (AML), particularly when myelomonocytic features , hyperleukocytosis, and/or a coagulation disorder are initially present. C ommonly, these complications arise during increasing leukocyte counts (WBCs ). METHODS. The authors describe four patients with AML and hyperleukocytosis who developed leukostasis followed by parenchymal hemorrhage. RESULTS. Bleeding in all patients occurred while their WBCs were decreasing following cytosine-arabinoside chemotherapy, and in the absence of dissemi nated intravascular coagulation or severe thrombocytopenia. Radiologic and histopathologic findings underscoring possible mechanisms are presented in the article. CONCLUSIONS. Alterations of cell adhesion associated with chemotherapy-indu ced blast lysis or cellular differentiation are possible factors contributi ng to this particular sequence (cytosine arabinoside-based chemotherapy, le ukostasis, and subsequent hemorrhage). Prophylactic measures for managing t his early complication of AML treatment include leukapheresis to reduce the WBC prior to the initiation of chemotherapy. (C) 1999 American Cancer Soci ety.