Pericardial tamponade in chronic myelomonocytic leukemia.

We report four cases of malignant pleuropericardial effusions in patients with chronic phase myelomonocytic leukemia (CMML). Based on current literature, this event is rare and very poorly understood. Our cases shed light on three important clinical characteristics: (1) patients with CMML develop effusions during uncontrolled leukocytosis; (2) these effusions are very responsive to conventional chemotherapy; and (3) effusions may develop without clinical forms of disease in other sites of extramedullary hematopoiesis.