Disseminated intravascular coagulation in hematologic malignancies

Disseminated intravascular coagulation (DIC) significantly contributes to the bleeding and thrombotic complications in patients with hematologic malignancies. As shown in other cancer settings, an underlying condition of activation of the coagulation system leading to a prothrombotic state of chronic or subclinical DIC is detectable. A variety of disease- or treatment-related factors may affect this condition, enhancing the risk of thrombosis or of bleeding and further triggering mechanisms of DIC in this setting. An overt DIC is diagnosed in approximately 15% of patients with acute leukemia, and bleeding manifestations prevail over thrombosis, with the highest and most harmful clinical impact in acute promyelocytic leukemia (APL). Pathogenic mechanisms include a series of intrinsic properties of malignant cells, able to directly activate the coagulation system or to stimulate prothrombotic effects by the host cells. Moreover, chemotherapy or concomitant infections play an important concurrent role. In this review the coagulation abnormalities, clinical manifestations, and the presently known pathophysiologic mechanisms of DIC in patients with hematologic malignancies are discussed, focusing on the most extensively studied condition of APL. Current approaches and open issues for the management and treatment of these patients are also reviewed.