Use of Hematopoietic Growth Factors in Elderly Lung Cancer Patients Receiving Chemotherapy A SEER-Medicare-based Study

Objectives: Hematopoietic growth factors (HGFs) are essential for successful completion of chemotherapy in lung cancer patients. However, because of their adverse effects, clinical guidelines recommend their use in only selective clinical scenarios. This study, for the first time, explores patient characteristics and temporal trends associated with HGF utilization among elderly lung cancer patients receiving chemotherapy. Methods: This is a retrospective analysis of the Surveillance, Epidemiology, and End Results (SEER)-Medicare linked data containing 80,940 patients, aged 65 years and older, diagnosed with stage I to TV lung cancer between 1992 and 2009, and who received chemotherapy. Descriptive statistics and logistic regressions were used to examine the characteristics associated with 2 types of HGFs colony stimulating factors (CSFs) and erythropoiesis-stimulating agents (ESAs). Results: Twenty-five percent of the patients received CSFs and 42% received ESAs. Temporal variations were most predictive of HGF utilization, with an increase from 2.6% in 1992 to 47.3% in 2009 for CSFs and 1.3% to 30.5% for ESAs. Higher chemotherapy-based risk profiles increased the odds of HGF receipt 2 to 3 times (P<0.0001). Even after controlling for relevant clinical characteristics, unexplained sociodemographic associations persisted, suggesting lack of compliance with HGF guidelines. Conclusions: There has been a significant increase in the use of HGFs over time. Although chemotherapy-based risk profiles were significant predictors of HGF receipt, the study results suggest possible lack of compliance with treatment guidelines, which should be investigated. Given the high cost of HGFs, future studies are also needed to determine cost-effectiveness of these drugs among lung cancer patients.