[The Clinical Utility of Pegfilgrastim in Combination with Adjuvant FEC(100)and TC Chemotherapy for Breast Cancer].

BACKGROUND: More than 20%of breast cancer patients who undergo myelosuppressive chemotherapy involving FEC(100) or TC experience febrile neutropenia(FN), and pegfilgrastim is commonly recommended as the primary prophylaxis. Delays and/or dose-reductions in chemotherapy should be avoided as much as possible to maximize the clinical benefits of these adjuvant chemotherapies.

PURPOSE: This study assessed the relative dose intensity(RDI), efficacy, and safety of pegfilgrastim in patients with breast cancer. The incidence of FN was also evaluated.

METHODS: Twenty-six patients with breast cancer undergoing FEC(100)or TC were included in this retrospective study.

RESULTS: Of the 26 patients, 19 patients who underwent FEC(100)and 7 patients who underwent TC received 3.6 mg of pegfilgrastim 24 hours after administration of the myelosuppressive chemotherapy. Four and 14 patients who underwent FEC(100)achieved 85-99% and 100% RDI, respectively. All 7 patients who underwent TC achieved 100% RDI. Grade 3 and 4 adverse events, as assessed using the CTCAE, were observed in 11 patients who underwent FEC(100): 2 patients experienced leukocytopenia, 7 experienced neutropenia, 1 experienced thrombocytopenia, and 1 experienced FN. Four patients who underwent TC experienced Grade 3 and 4 adverse events: 1 patient each experienced bone pain, neutropenia, anemia, and FN.

CONCLUSIONS: Pegfilgrastim can reduce the incidence of FN and maintain RDI in patients with breast cancer undergoing myelosuppressive chemotherapy.