Effect of G-CSF Prophylaxis With Chemotherapy for Breast Cancer on Neutropenia-Related Hospitalization
In an analysis of commercial U.S. health plan data reported in the Journal of Clinical Oncology, Agiro et al found that granulocyte colony-stimulating factor (G-CSF) primary prophylaxis was associated with a “low-to-modest’’ benefit in preventing neutropenia-related hospitalization in breast cancer patients receiving chemotherapy associated with a low-to-intermediate risk of febrile neutropenia.
Study Details
The study involved 8,745 patients aged ≥ 18 years from a medical and pharmacy claims database for 14 commercial U.S. health plans who started chemotherapy from 2008 to 2013 with docetaxel and cyclophosphamide (n = 4,815—2,849 with prophylaxis and 1,966 without); docetaxel, carboplatin, and trastuzumab (Herceptin; TCH; n = 2,292—1,444 with prophylaxis and 848 without); or conventional-dose doxorubicin and cyclophosphamide (n = 1,638—857 with prophylaxis and 781 without). G-CSF primary prophylaxis was defined as administration within 5 days of starting chemotherapy. The outcome of interest was neutropenia-, fever-, or infection-related hospitalization within 21 days of starting chemotherapy.
Effect on Risk
Primary prophylaxis was associated with a significantly reduced risk of neutropenia-related hospitalization in patients receiving docetaxel and cyclophosphamide (2.0% with vs 7.1% without; adjusted odds ratio [OR] = 0.29, 95% confidence interval [CI] = 0.22–0.39) and in those receiving TCH (1.3% with vs 7.1% without; adjusted OR = 0.19, 95% CI = 0.12–0.30). No risk reduction was observed among patients receiving doxorubicin and cyclophosphamide (4.7% with vs 3.8% without; adjusted OR = 1.21, 95% CI = 0.75–1.93).
The estimated number needed to treat with prophylaxis to prevent 1 neutropenia-related hospitalization was 20 for docetaxel and cyclophosphamide and 18 for TCH.
The investigators concluded: “Primary G-CSF prophylaxis was associated with low-to-modest benefit in lowering neutropenia-related hospitalization in patients with breast cancer who received [docetaxel and cyclophosphamide] and TCH regimens. Further evaluation is needed to better understand which patients benefit most from G-CSF prophylaxis in this setting.”
The study was funded by Anthem.
Abiy Agiro, PhD, of HealthCore, Wilmington, Delaware, is the corresponding author of the Journal of Clinical Oncology article.
The content in this post has not been reviewed by the American Society of Clinical Oncology, Inc. (ASCO®) and does not necessarily reflect the ideas and opinions of ASCO®.
