Iron in Hodgkin's lymphoma.

Anemia is a frequent finding of Hodgkin's lymphoma (HL) diagnosis. It is usually mild, with hemoglobin levels between 10 and 12 g/dl; it is rarely (<10% of cases) a result of bone marrow infiltration; and it displays the characteristics of the anemia of chronic disease due to abnormalities in iron metabolism. The inflammatory cytokine IL-6 is frequently up-regulated in Hodgkin's lymphoma, and IL-6 levels are strongly associated with hepcidin, the main regulator of iron metabolism. Elevated hepcidin levels result in iron restriction and signs of anemia of chronic disease. In addition, the abundant microenvironment surrounding the neoplastic Hodgkin's and Reed-Sternberg cells may contribute to alterations in iron metabolism. Tumor-infiltrating macrophages can sequester iron using scavenger receptors. Iron-restricted anemia at HL diagnosis can be aggravated by intensive chemotherapy, and iron overload may become clinically relevant in heavily treated patients with relapsed or refractory disease undergoing high-dose chemotherapy and stem cell transplantation.