Background

Incidence of febrile neutropenia (FN) caused by docetaxel/cyclophosphamide (TC) therapy varies widely from country to country (5% at US Oncology research trial and 68.8% at Japanese trial), and the high hematotoxicity observed in Japanese patients may reduce relative dose intensity (RDI).

Methods

Between April 2009 and June 2017, 205 patients with breast cancer received TC therapy (75/600 mg/m2, every 3 weeks, 4 cycles). We investigated the incidence of FN and RDI of TC therapy and the factors related to FN and low RDI.

Results

The median patient age was 53 years. Fifty-five patients received primary prophylactics (20 granulocyte-colony stimulating factor (G-CSF) and 35 antibiotics). Excluding 9 patients with allergic reaction, FN occurred in 68 patients (34.7%). Among patients with primary prophylactic G-CSF, only one developed FN, whereas FN occurred in all the 11 patients with prophylactic antibiotics. Hospitalization was required in 6.3% of patients. In multivariate analysis, the independent risk factors of FN were older age (≥60 years, p = 0.017) and without primary prophylactic G-CSF (p = 0.011). The median RDIs of docetaxel and cyclophosphamide were 96.7% and 99.7%, respectively. Low RDI (<85%) was related to older age (p < 0.001), but not to primary prophylactics (G-CSF p = 0.247 and antibiotics p = 0.862). Table: 74P

Predictors of FN incidence

Conclusions

Even though the FN incidence of TC therapy was over 20%, low hospitalization rate and high RDI were achieved in Japanese patients. Primary prophylactic G-CSF was useful to reduce FN of TC therapy for breast cancer, especially in older patients.

Legal entity responsible for the study

Hiroshima University

Funding

None

Disclosure

All authors have declared no conflicts of interest.