Background: In adjuvant settings,
epirubicin and
cyclophosphamide (EC) and
docetaxel and
cyclophosphamide (TC) are both optional
chemotherapy regimens for lymph node-negative,
hormone receptor (HR)-positive, human epidermal receptor 2 (HER2)-negative
breast cancer patients.
Neutropenia is one of the most common adverse events (AEs) of these regimens. The rate of grade 3−4
neutropenia varies in different studies, and direct comparisons of safety profiles between EC and TC are lacking. Method: ELEGANT (NCT02549677) is a prospective, randomized, open-label, noninferior hematological safety trial. Eligible patients with lymph node-negative HR+/HER2-
tumors (1:1) were randomly assigned to received four cycles of EC (90/600 mg/m2) or TC (75/600 mg/m2) every three weeks as
adjuvant chemotherapy. The primary endpoint was the incidence of grade 3 or 4
neutropenia defined by National Cancer Institute-Common Terminology Criteria for Adverse Events (NCI-CTCAE) version 4.0 on an intention-to-treat basis. Noninferiority was defined as an upper 95% CI less than a noninferiority margin of 15%. Results: In the intention-to-treat population, 140 and 135 patients were randomized into the EC and TC arms, respectively. For the primary endpoint, the rate of grade 3 or 4
neutropenia is 50.71% (95% CI: 42.18%, 59.21%) in the EC arm and 48.15% (95% CI: 39.53%, 56.87%) in the TC arm (95%CI risk difference: −0.100, 0.151), showing the noninferiority of the EC arm. For secondary endpoints, the rate of all-grade
anemia is higher in the EC arm (EC 42.86% versus TC 22.96%, p = 0.0007), and more patients suffer from
nausea/
vomiting,
hair loss, and nail changes (p < 0.01) in the EC arm. No statistically different disease-free survival was observed between the two arms (p = 0.13). Conclusion: EC is not inferior to TC in the rate of grade 3 or 4
neutropenia, but more other AEs were observed in the EC group.