Variation in the use of granulocyte-colony stimulating factor for dose dense paclitaxel: A single institution retrospective study.

INTRODUCTION: The necessity of using granulocyte-colony stimulating factor (G-CSF) during dose-dense (DD) paclitaxel (T) after doxorubicin and cyclophosphamide (AC) is unclear.

METHODS: This was a retrospective cohort study including patients with stage I-III breast cancer treated at Dana-Farber Cancer Institute with adjuvant DD-ACT between January 2011 and December 2013. Descriptive analyses evaluating patterns of G-CSF utilization during T were performed.

RESULTS: Overall, 156 patients were treated with DD-ACT by 26 providers. The majority of patients (135, 87%) received at least one dose of G-CSF during T (group 1), 17% of these patients received it in only one cycle and 48% received it in all four cycles. Reasons for omitting G-CSF included high baseline absolute neutrophil count and pain. Twenty-one (13%) patients did not receive any G-CSF during T (group 2). Respectively, 94% and 90% of patients completed the treatment in groups 1 and 2. There were no cases of treatment cessation due to neutropenia. Six percent of patients in group 1 had at least one treatment delay. There were no treatment delays reported in group 2. Variation in the use of G-CSF by provider and by patient was found, with 11 providers choosing not to use G-CSF in at least one patient.

CONCLUSIONS: We identified substantial variation in the use of G-CSF within the practice. However, omission of G-CSF was not associated with treatment delays or adverse events. Prospective studies are warranted to formally test whether routine G-CSF is necessary during dose-dense T therapy.