ORLANDO, Fla.—Intravenous iron should be used for the treatment of patients with cancer-related anemia; those treated have better hematopoietic response and less need for transfusion, with no difference in mortality or adverse events.
That’s the conclusion of a systematic review and meta-analysis conducted by Anat Gafter-Gvili, MD, of Rabin Medical Center, Beilinson Hospital and Sackler School of Medicine, Petah-Tikva, Israel, and colleagues, the results of which were presented in a poster session during the 52nd American Society of Hematology Annual Meeting and Exposition.
Anemia, an almost universal complication in patients with cancer, is an important contributor to morbidity of malignancy. Currently available guidelines recommend use of erythropoiesis stimulating agents (ESAs) for chemotherapy-induced anemia; however, these guidelines are less certain regarding the administration of intravenous (IV) iron.
The investigators performed a comprehensive search of The Cochrane Library, MEDLINE, conference proceedings, and references for randomized controlled trials published between 2000 and 2010 that compared IV iron with no iron or oral iron for the treatment of chemotherapy-induced anemia. Two reviewers appraised the quality of the trials, extracted data, and conducted a systematic review and meta-analysis.
Primary outcomes assessed were number of patients achieving a hematopoietic response (defined as an increase in hemoglobin level by >2 g/dl or an increase >12 g/dl), number of patients requiring blood transfusions. Secondary outcomes included ferritin level at the end of the trial, absolute transferrin saturation (TSAT) at the end of the trial and change from baseline, all-cause mortality, and adverse events. For dichotomous data, relative risks (RR) with 95% confidence intervals (CIs) were estimated and pooled; for continuous data, weighted mean differences (WMDs) were calculated.
Ten randomized trials selected from between 2004 and 2009 were included in the meta-analysis (n=1637). Interventions included IV iron dextran in 2 trials; ferric gluconate in 3, iron sucrose in 4, and both ferric gluconate and iron sucrose in 1 trial. In 9 of the trials, ESAs were administered. Most of the trials excluded patients with true iron deficiency.
Treatment with IV iron significantly increased the number of patients achieving a hematopoietic response (RR 1.31 [95% CI, 1.15-1.49], 8 trials), and significantly reduced the number of patients who required blood transfusions (RR 0.77 [95% CI, 0.64-0.94], 9 trials). Please click here for more study data. When analyzed according to type of ESA administered to both arms of the randomized trials, the number of patients with a hematopoietic response in the IV iron arm was consistently significantly increased for all ESA types: darbepoetin alpha (RR 1.18 [95% CI, 1.11-1.26], 5 trials), epoetin alpha (RR 1.85 [95% CI, 1.25-2.74], 2 trials), epoetin beta (RR 1.66 [95% CI, 1.18-2.34], 1 trial).
Ferritin level at the end of the trial was significantly increased in the IV iron arm compared with the control arm (WMD 234.47 [95% CI, 136.94, 332.01], 4 trials), as was transferrin saturation (WMD 9.98 [95% CI, 9.21, 10.75] 3 trials). No difference in all-cause mortality at the end of follow-up between the IV iron and control arms was observed (RR 1.01 [95% CI, 0.65, 1.56], 6 trials). No differences were found in rate of serious adverse events requiring intervention (RR 1.11 [95% CI, 0.93, 1.31], 7 trials) or occurrence of thromboembolic (RR 1.03 [95% CI, 0.59, 1.80], 4 trials) or cardiovascular events (RR 0.87 [95% CI, 0.45, 1.70] [0.40-3.39], 5 trials).