Background: Racial disparities in clinical outcomes between Caucasian and African American (AA) MBC patients have been identified. Some of these disparities may be attributed to differences in toxicities and access to supportive care interventions. In this study, treatment toxicities and use of supportive care were compared between Caucasian and AA MBC patients treated in 15 community oncology practices across the United States.
Methods: Between 2009 and 2010, 264 MBC patients (198 Caucasians, 66 AAs) met the inclusion criteria. Data collection included baseline patient and disease characteristics, biochemistry, hematology, type of cytotoxic therapy by line of treatment (for the first three lines), use of supportive care drugs and incidence of dose limiting toxicities. Results were presented only descriptively. Socioeconomic data were not collected in this population.
Results: AA patients had significantly lower hemoglobin levels at baseline (12.5 vs 11.5 g/dL) and the levels remained lower throughout the first three lines of therapy. This resulted in significantly higher use of erythropoietin stimulating agents (28.8% vs 15.2%) and blood products (13.6% vs 7.6%) in AA. In contrast, neutropenia (33.9% vs 23.4%), G-CSF use (32.3% vs 28.8%) and diarrhea (21.3% vs 8.5%) were more common in Caucasian patients. The incidence of emesis (12.6% vs 8.5%) and anti-emetic support was similar between Caucasian and AA patients (77.3% vs 78.8% during 1st line chemotherapy). However, chemotherapy dose reductions and delays due to toxicity were higher in Caucasians than AA patients during 1st line and 3rd line chemotherapy (32.8% vs 21.2% and 43.2% vs 28.1%, respectively) and correspondingly, more medical interventions to treat toxicities were observed in Caucasian patients.
Conclusions: In this exploratory analysis, differences in the incidence of dose limiting toxicities such as anemia, neutropenia and diarrhea as well as supportive pharmacotherapy and blood products were identified between groups. Research in larger populations is warranted to better understand cancer treatment toxicities and outcomes across racial groups.
