Can Cancer Cause an Iron Deficiency in Blood?

Nurse taking a blood test from a senior's arm
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Iron deficiency anemia occurs when the body has too little iron to make red blood cells. If you have an iron deficiency, it usually resulted from a bleed somewhere in your body. Women often become slightly anemic from a heavy menstrual flow. A traumatic injury involving loss of blood, surgery or childbirth can cause enough blood loss to create an iron shortage. You could also become anemic if you have anorexia or eat a diet too low in iron. Diseases like cancer also create a low level of iron.


Iron deficiency anemia can cause you to feel very tired and weak, have shortness of breath and heart palpitations and feel lightheaded to the point of fainting. The cause of the anemia will produce other symptoms such as bleeding from the vagina or rectum, blood in the urine, vomiting blood or nosebleeds. In mild cases, you might not experience any symptoms at all. Laboratory blood tests will confirm whether you have anemia. Determining the source of the anemia can lead to a reversal of the anemia if the condition receives treatment. However, sometimes the cause of the anemia resists treatment, which happens often in cancer cases.


Cancer and Iron Deficiency

Because blood loss usually accounts for low iron levels, certain cancers associated with bleeding bring on anemia. These include colon, rectal, stomach and esophageal cancers. Cancer thrives in an inflammatory state, so as it produces more inflammation, it causes body tissues to bleed. Besides cancer of the gastrointestinal tract, Crohn's disease and celiac disease also produce inflammation and bleeding. This inflammatory state in the colon also inhibits the proper absorption of iron and other nutrients.

Chemotherapy and Iron Deficiency

The medicines for treating cancer during chemotherapy can contribute to low iron stores by preventing the body from fully absorbing iron. Because iron aids in the process of erythropoietin, or the creation of red blood cells, a shortage impairs the production of the amount of red blood cells needed to circulate oxygen to the body's tissues. The lack of oxygen robs you of energy and causes the other symptoms of anemia.



In cancer induced iron deficiency anemia, the degree of anemia determines treatment. Anemia treatment usually involves taking supplements of iron, but if the cancer drugs block the absorption, this approach does not work. Erythropoietin-stimulating agents enable the body to create more red blood cells, which in turn carry more oxygen throughout the body. In the most severe cases of anemia, a blood transfusion may be necessary. The new blood supply renders immediate results, but the treatment carries the risks of an allergic reaction and rejection. Special consideration is given to patients with a cardiovascular history. The clinician will weigh the risks against the benefits more heavily.


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