In cancer, several cytokines namely tumor necrosis factor -α (TNF-α), transforming growth factor -β (TGF-β), interleukin-1 (IL-1), IL-6 and interferon-γ interfere normal erythrocyte production by modulating iron metabolism and blunting erythropoietin effect thereby causing anemia [5]. This evidence concerns the gene IL6 and anemia (phenotype).