Effects of primary granulocyte-colony stimulating factor prophylaxis on neutropenic toxicity and chemotherapy dose delivery in Chinese patients with breast cancer who received adjuvant docetaxel plus cyclophosphamide chemotherapy: a retrospective cohort study.

ABSTRACT

INTRODUCTION: This study was performed to examine the effects of primary granulocyte-colony stimulating factor (G-CSF) prophylaxis on neutropenic toxicity, chemotherapy delivery, and hospitalisation among Chinese patients with breast cancer in Hong Kong. METHODS: This retrospective study included patients with breast cancer who received adjuvant docetaxel plus cyclophosphamide chemotherapy from November 2007 to October 2013 at Princess Margaret Hospital. Data were collected regarding the usage of G-CSF prophylaxis; incidences of grade 3 or 4 neutropenia, febrile neutropenia, non-neutropenic fever, and infection; hospital admissions, and chemotherapy dose delivery. Patients who began to receive G-CSF prophylaxis during the first cycle of chemotherapy and continued such prophylaxis in subsequent cycles were regarded as the primary G-CSF prophylaxis group. RESULTS: In total, 231 female Chinese patients with breast cancer were included in the analysis. Overall, 193 (83.5%) patients received primary G-CSF prophylaxis. The demographics and tumour characteristics were comparable between patients with and without primary G-CSF prophylaxis. Primary G-CSF prophylaxis significantly reduced febrile neutropenia incidence from 31.6% to 14.5% (relative risk=0.45, 95% confidence interval=0.25-0.81). Primary G-CSF prophylaxis also significantly reduced the incidence of grade 3 or 4 neutropenia from 57.9% to 24.7% (relative risk=0.43, 95% confidence interval=0.30-0.62) and the incidence of febrile neutropenia-related hospital admission from 31.6% to 12.4% (P=0.025). Finally, it enabled more patients to receive adequate chemotherapy dose delivery. CONCLUSION: Primary G-CSF prophylaxis effectively reduced the incidences of grade 3 or 4 neutropenia and febrile neutropenia, while enabling adequate chemotherapy dose delivery and reducing hospital admissions among Chinese patients with breast cancer who received adjuvant docetaxel plus cyclophosphamide chemotherapy.