Iron metabolism and iron supplementation in cancer patients
Iron deficiency and iron deficiency-associated anemia are common complications in cancer patients. Most iron deficient cancer patients present with functional iron deficiency (FID), a status with adequate storage iron, but insufficient iron supply for erythroblasts and other iron dependent tissues. FID is the consequence of the cancer-associated cytokine release, while in absolute iron deficiency iron stores are depleted resulting in similar but often more severe symptoms of insufficient iron supply. Here we present a short review on the epidemiology, pathophysiology, diagnosis, clinical symptoms, and treatment of iron deficiency in cancer patients. Special emphasis is given to intravenous iron supplementation and on the benefits and limitations of different formulations. Based on these considerations and recommendations from current international guidelines we developed recommendations for clinical practice and classified the level of evidence and grade of recommendation according to the principles of evidence-based medicine.
Iron (Fe), an important trace element, plays a vital role in oxygen metabolism, oxygen uptake, and electron transport in mitochondria, energy metabolism, muscle function, and hematopoiesis. Iron, therefore, is essential for physical functioning and wellbeing, but free bivalent iron is quickly oxidized to its trivalent iron, which when available in its free form can induce the formation of free oxygen radicals which may result in tissue damage. Therefore, iron metabolism is tightly controlled to ensure that free iron levels are kept as low as possible, and to guarantee adequate iron absorption, transport, and storage.
Univ.Prof. Dr. Heinz Ludwig, Dr. Rayko Evstatiev, Univ.Prof. Dr. Gabriela Kornek, Univ.Prof. Dr. Matti Aapro, Univ.Prof. Dr. Thomas Bauernhofer, Dr. Veronika Buxhofer-Ausch, Univ.Prof. Dr. Michael Fridrik, Univ.Prof. Dr. Dietmar Geissler, Univ.Prof. Dr. Klaus Geissler, Univ.Prof. Dr. Heinz Gisslinger, Dr. Elisabeth Koller, Dr. Gerhard Kopetzky, Dr. Alois Lang, Priv.Doz. Dr. Holger Rumpold, Univ.Prof. Dr. Michael Steurer, Dr. Houman Kamali, Univ.Prof. Dr. Hartmut Link, Wiener klinische Wochenschrift 23/24/2015