Background: Anemia is common among patients with newly diagnosed cancer, may be exacerbated by cancer therapies, and leads to radioresistance by lowering oxygen levels in the tumor microenvironment. Herein, the effect of breast irradiation on hemoglobin levels and outcomes in breast conservation therapy is reported.
Patients and methods: Medical records of 1368 women with stage 0, I, and II breast cancer treated with breast conservation therapy from 1977-2002 were reviewed. Hemoglobin levels at baseline as well as during and after radiation were recorded. Patterns of hemoglobin changes and the effect of anemia on local control and survival outcomes were assessed. Median follow-up time was 8 years for the normal group and 6 years for the anemic group.
Results: Baseline anemia was seen in 18% of the patients, 90% of whom had mild anemia (hemoglobin, 11.9-10.0 g/dL). Anemia was recorded in 21% during radiation. Among patients with normal baseline hemoglobin levels, 6.5% of the patients became anemic during radiation. Of those with baseline anemia, 72% had stable to improved hemoglobin levels during radiation, and 22% declined by a median of 0.3 g/dL. There were no significant differences in local or regional recurrence, overall, disease-free, cause-specific, or distant disease-free survival between patients with baseline anemia or with normal hemoglobin.
Conclusion: Radiation does not contribute significantly to anemia during breast conservation treatment, and mild anemia does not affect outcomes. It is unnecessary to obtain routine hemoglobin levels during radiation therapy. There is no difference in outcomes based on hemoglobin levels; thus, there is no reason to transfuse or provide erythropoiesis-stimulating agents for hemoglobin levels > 10 g/dL during radiation treatment of the breast.