Purpose. We evaluated the incidence and severity of anemia experienced by women treated with doxorubicin and cyclophosphamide (AC) therapy for early-stage breast cancer are described. We also explored the possibility of identifying clinical characteristics that will allow early identification of women more likely to develop anemia and may require anemia treatment.
Methods. This study used a historic case series from 13 oncology practices that participated in the Oncology Practice Pattern Study. The analysis focused on 411 patients who received AC chemotherapy from 1993 through 1999. Seventeen percent of the study population was excluded from the analysis due to missing data. Anemia was defined as a hemoglobin (Hb) value of < 12 g/dL. Hb ≤10 g/dL was considered the threshold value for treatment.
Results. Among patients receiving AC, 18.0% was anemic prior to chemotherapy. Overall, 14.9 -16.9% of women with early-stage breast cancer who started AC chemotherapy with a normal Hb (≥12 g/dL) developed anemia. Nearly 11% developed severe to life-threatening anemia (Hb < 8 g/dL). Data on blood transfusions and erythropoietic therapy were unavailable. Multivariate logistic regression analysis showed that patients who started with a normal prechemotherapy Hb and dropped to ≤10 g/dL at some point during chemotherapy were more likely to be ≥65 years of age, have a low body surface area (< 1.78), and have four or more positive nodes.
Conclusion. The incidence of anemia increased substantially from baseline to post-chemotherapy. The data suggested the importance of monitoring and managing Hb levels of patients at increased risk for developing chemotherapy-induced anemia.