Pseudochloroma: extramedullary hematopoietic nodules in chronic myelogenous leukemia.

Five patients with chronic myelogenous leukemia had multiple hemorrhagic soft tissue lesions at the time of diagnosis. Histologic examination of tissue removed by biopsy and at autopsy revealed extramedullary hematopoietic nodules with associated hemorrhage and necrosis. No evidence of either blastic transformation or systemic bleeding diathesis was found. Pseudochloroma is a treatable although potentially fatal complication of uncontrolled chronic myelogenous leukemia and should not be confused with myeloblastomas occurring with blastic transformation. Early recognition of the syndrome, prompt treatment with intensive chemotherapy, and radiation therapy of intracranial lesions seem to provide effective control of this complication and reversion to a status that is responsive to conventional treatment of chronic myelogenous leukemia.