The use of blood transfusions to correct anemia is a therapeutic modality for which there is less literature available for patients with cancer. Consequently, few studies are able to provide high-level evidence on the efficacy and safety of this modality. The chief aim of transfusion is to immediately correct the signs or symptoms resulting from anemia. Typically, there is a growing need for blood transfusions in individual cancer patients as the number of chemotherapy cycles administered increases. However, there is wide variation in the level of hemoglobin that triggers blood transfusions among the various studies and among different types of cancers.
There is general medical consensus that blood transfusion should be used in patients with terminal illness when there is acute blood loss or chronic deterioration of the patient, when hemoglobin levels are below 7 g/dl, in anemic patients with respiratory or heart symptoms or in patients with anemia due to chemotherapy. However, the trigger level of hemoglobin and its target values have not been determined. On the other hand, the EORTC guidelines mention that patients with hemoglobin levels of less than 9 g/dl should primarily be evaluated for the need of transfusions. The ASH/ASCO guidelines suggest that blood transfusions may be an option for the correction of anemia associated with chemotherapy when hemoglobin levels are less than 10 g/dl or for elderly patients with limited cardiopulmonary reserve, patients with coronary disease or symptomatic angina, those with substantial reduction in exercise capacity or those with difficulty in performing daily activities.
The results of a number of studies evaluating the impact of transfusion on mortality in critically ill patients are conflicting. One study of 56 esophageal cancer patients receiving chemoradiation therapy demonstrated that blood transfusions increased overall survival. However, there is evidence in the literature that blood transfusion may have a negative impact on the progression of disease. Fyles and colleagues analyzed the published data from a randomized trial and found that transfusion in anemic patients with cervical cancer did not result in benefit. In a retrospective study of 70,542 patients hospitalized with cancer, the use of blood transfusion was associated with higher rates of venous and arterial TEs, in addition to an increased risk of hospital mortality. However, the causal relationship could not be established owing to the retrospective nature of the study. There are other potential hazards related to blood transfusion. Some of the currently known blood contaminants include hepatitis A virus, cytomegalovirus, Epstein–Barr virus, human herpesvirus 8, Toxoplasma gondii, parvovirus B-19, West Nile virus, spongiform encephalopathy prions, Trypanosoma cruzi, Babesia species and Plasmodium species, although the introduction of numerous safety interventions for infectious organisms has dramatically decreased the incidence of transfusion-related infections.[72,73] Other transfusion reactions include febrile nonhemolytic transfusion reaction, bacterial infection, acute hemolytic reaction, anaphylactic reaction, transfusion-associated acute lung injury, volume overload, iron overload, delayed hemolytic reaction, transfusion-associated graft-versus-host disease and post-transfusional purpura. At present, blood transfusion is not a proven safe alternative to ESAs, as comparative studies have not been performed and, in contrast to ESAs, little is known about the potential long-term side effects.
Future Oncol. 2011;7(4):507-517. © 2011 Future Medicine Ltd.
Cite this: Management of Anemia in Cancer Patients - Medscape - Apr 01, 2011.