Evaluation and Treatment of Iron Deficiency for the Practicing Oncologist

Iron deficiency is highly prevalent in patients with cancer and has major impacts on morbidity and quality of life. The etiologies of cancer-related iron deficiency are multifactorial, and unlike in the noncancer population, most patients with cancer-related iron deficiency have functional iron deficiency due to cancer-related inflammation. Diagnosis of iron deficiency in patients with cancer requires different thresholds compared with patients without cancer. Treatment of iron deficiency requires adequate dosing of iron repletion and specific understanding of patient context (ie, perioperative anemia, concomitant use of erythropoiesis-stimulating agents, use of anthracycline chemotherapy). Intravenous (IV) iron is generally preferred over oral iron for iron repletion due to a favorable safety profile and improved bioavailability particularly in patients with cancer-related inflammation. IV iron formulations have similar efficacy, and the choice of one over the other depends on formulary, local availability, and number of infusions required to achieve a therapeutic dose. Serious infusion-related adverse effects are rare, whereas mild infusion reactions (ie, Fishbane reactions) are typically self-limiting and retrial of the same formulation or an alternative formulation is generally well tolerated. Clinicians, pharmacists, and nurses administering IV iron should be well versed in recognizing and managing mild reactions. The goal of this review is to aid clinicians in recognizing iron deficiency and to provide a framework to treat iron deficiency in patients with cancer.