Effect of eribulin on patients with metastatic breast cancer: multicenter retrospective observational study in Taiwan.

Purpose: The aim of this study was to confirm the therapeutic role of eribulin on Taiwanese women with metastatic breast cancer.
Methods: This retrospective study examined 449 females who received eribulin between March 2014 and June 2017 at 14 hospitals in Taiwan for treatment of locally advanced or metastatic breast cancer.
Results: The survival rate at 24 months was 57.2% (95% CI 51.0-62.9%) and the median time to treatment failure (TTF) was 3.91 months (95% CI 3.45-3.94). A total of 175 patients (40.1%) received eribulin for fewer than 90 days and the others received it for 90 days or more. Eight patients (1.83%) had complete remission, 82 (18.8%) had partial remission, 202 (46.3%) had stable disease, and 144 (33.0%) had progressive disease (PD). Patients' tumors with the luminal A subtype had a significantly better objective response rate. Kaplan-Meier analysis indicated that hormone receptor positivity, luminal A subtype, receipt of eribulin as the 1st to 3rd line therapy, and metastasis to fewer than 4 organs were significantly associated with longer TTF. Stepwise multivariate analysis showed that only receipt of eribulin as the 1st to 3rd line therapy was significantly associated with TTF (HR 1.49, p < 0.001). All toxicities were manageable and only 18 patients (4.1%) discontinued treatment due to adverse events.
Conclusions: Eribulin appears to have better efficacy and cause fewer adverse events, especially neutropenia, in Taiwanese women than Western women.