Anemia in diffuse large B-cell non-Hodgkin lymphoma: the role of interleukin-6, hepcidin and erythropoietin

Anemia is a frequent sign in patients with diffuse large B-cell lymphoma (DLBCL) at diagnosis. We determined erythropoietin, hepcidin and interleukin-6 (IL-6) in plasma samples of 53 patients with DLBCL. The majority of patients (40/53, 75%) showed defective endogenous erythropoietin production, in particular when anemia was present (p = 0.01). Hepcidin plasma levels were significantly higher in patients compared to controls (p = 0.006), particularly in those with characteristics associated with a more active disease, including elevated lactate dehydrogenase (LDH) (p = 0.0004), B-symptoms (p = 0.07) and an age-adjusted international prognostic index (IPI) score > 1 (p = 0.01). Hepcidin levels correlated strongly to ferritin (r = 0.77, p < 0.0001) and weakly to IL-6 concentrations (r = 0.30, p = 0.03), but not to hemoglobin values. IL-6 inversely correlated to hemoglobin values in both univariate and multivariate analysis (p = 0.04), including hepcidin and erythropoietin as variables. Our findings suggest that elevated hepcidin levels and inadequate erythropoietin response are frequent in DLBCL, but elevated IL-6 plays the major role for the development of anemia.