Internal Medicine, Pennsylvania Hospital, University of Pennsylvania Health System, Philadelphia, PA, USA
Abstract: Chemotherapy-induced anemia [CIA] is a multifaceted entity influenced by a variety of patient- and treatment-specific factors. Some sources of variation within CIA include chemotherapeutic agent as well as dose and administration schedule, type and stage of malignancy, baseline pretreatment hemoglobin, target hemoglobin, timing of intervention [red blood cell transfusion, iron, erythropoietin stimulating agent], nutritional status, renal function, age, and gender. The diversity of patient presentation and symptomatology within the broader spectrum of CIA contributes to the challenge of establishing universal criteria to govern optimal management therapies. This manuscript will review the development and evolution of CIA with an emphasis on assorted therapeutic interventions.
Keywords: chemotherapy-induced anemia, red blood cell transfusion, erythrocyte stimulating agent, iron
Introduction
Anemia, derived from the Greek word “anaimia” meaning lack of blood, refers to a decreased oxygen-carrying capacity in the blood and is commonly associated with cancer. Anemia is the most common and persistent hematological abnormality in oncology patients. Chemotherapy-induced anemia [CIA] is a consequence of malignant invasion of normal tissue leading to blood loss, bone marrow infiltration with disruption of erythropoiesis, and functional iron deficiency as a consequence of inflammation. CIA is a significant consequence of chemotherapy and may delay or limit therapy as well as contribute to both fatigue and diminished quality of life. Unfortunately, not all clinicians consistently survey, measure, or even document anemia-related symptoms. Furthermore, there are inconsistent thresholds for both the definition and the severity of anemia. The lack of standardized objective grading systems of anemia and its varying manifestations make its quantitative evaluation challenging. Although some literature defines anemia by a reduction from baseline hemoglobin, the use of blood transfusions, or the use of recombinant human erythropoietin therapy, others fail to document the toxicity grading system used to define anemia. The National Cancer Institute Anemia Scale proposed the following grading scale for anemia:
- Grade 0 = Normal limits = hemoglobin 12–16 g/dL for women and 14–18 g/dL for men
- Grade 1 = Mild = 10–12 g/dL for women and 10–14 g/dL for men
- Grade 2 = Moderate = 8–10 g/dL
- Grade 3 = Severe = 6.5–8 g/dL
- Grade 4 = Life threatening =