Biological basis of anemia.
Anemia is a frequent complication in cancer, occurring in more than 50% of patients with malignancies. Several factors can cause anemia in these patients, such as blood loss, hemolysis, bone marrow infiltration, hypersplenism, and nutrient deficiencies. However, in a considerable number of patients, no cause other than malignant disease itself can be implicated. This cancer-related anemia is similar to the anemia observed in other chronic diseases, such as rheumatoid arthritis and some chronic infections. The syndrome of anemia of chronic disease is characterized by a hyporegenerative, normocytic, normochromic anemia associated with reduced serum iron and transferrin saturation but elevated (or normal) ferritin levels. Cancer-related anemia results from activation of the immune and inflammatory systems, leading to increased release of tumor necrosis factor, interferon-gamma, and interleukin-1. The cytokine-mediated relative failure of erythropoiesis has been further investigated, and three different mechanisms of action are proposed: (1) impaired iron utilization; (2) suppression of erythroid progenitor cells differentiation; and (3) inadequate erythropoietin production. In addition, the life span of red blood cells is shortened in cancer-related anemia and production cannot compensate sufficiently for the shorter survival time. Administration of recombinant human erythropoietin (r-HuEPO, epoetin alfa) can not only correct inadequate endogenous erythropoietin production, but also can overcome the suppression of erythroid progenitor cells and impairment of iron mobilization.
Bron
D
D
Institut Jules Bordet, Brussels, Belgium.
Meuleman
N
N
Mascaux
C
C
D000740:Anemia / Q000097:blood / Q000209:etiology*; D004920:Erythropoiesis / Q000502:physiology*; D004921:Erythropoietin / Q000096:biosynthesis; D006454:Hemoglobins / Q000378:metabolism; D006801:Humans; D009369:Neoplasms / Q000097:blood / Q000150:complications*
D006454:Hemoglobins; D004921:Erythropoietin