Risk of Neutropenia-Related Hospitalization in Patients Who Received Colony-Stimulating Factors With Chemotherapy for Breast Cancer

PurposeTo describe outcomes after granulocyte colony-stimulating factor (G-CSF) prophylaxis in patients with breast cancer who received chemotherapy regimens with low-to-intermediate risk of induction of neutropenia-related hospitalization.Patients and MethodsWe identified 8,745 patients age ≥ 18 years from a medical and pharmacy claims database for 14 commercial US health plans. This retrospective analysis included patients with breast cancer who began first-cycle chemotherapy from 2008 to 2013 using docetaxel and cyclophosphamide (TC); docetaxel, carboplatin, and trastuzumab (TCH); or doxorubicin and cyclophosphamide (conventional-dose AC) regimens. Primary prophylaxis (PP) was defined as G-CSF administration within 5 days of beginning chemotherapy. Outcome was neutropenia, fever, or infection-related hospitalization within 21 days of initiating chemotherapy. Multivariable regressions and number-needed-to-treat analyses were used.ResultsA total of 4,815 patients received TC (2,849 PP; 1,966 no PP); 2,29...