Abstract 1688
Background
The prognosis for triple negative (TN) and hormone-refractory metastatic breast cancer (MBC) remains poor and treatment options are limited to cytotoxic agents. Furthermore, the optimal sequence of chemotherapy (CT) is unclear. In this prospective cohort study (E-SPEC), we observed optimal sequences of CT for improving long-term survival. This trial was registered with ClinicalTrials.gov (no. NCT02551263).
Methods
The study was conducted under a multi-institutional prospective observational design and involved patients with HER2-negative hormone-refractory MBC. Eligibility criteria were age 20-75 years; refractory to hormone therapy defined as TN type or recurrence during or within 6 months after the end of adjuvant treatment or refractory to at least one previous hormone therapy for MBC; and scheduled for first- and second-line CT after registration. All treatments were performed according to physician’s choice. Treatment regimens, efficacies and quality of life (QoL) were prospectively surveyed. Baseline data analysis included patient characteristics, real-world CT sequence of first- and second-line CT regimen and the reason for cessation of first-line CT.
Results
Between June 2015 and July 2017, a total of 201 patients were enrolled, 194 of whom were analyzed. Mean age was 58.9 years; 142 patients (73.2%) had ER- and/or PgR-positive disease; 52 patients (26.8%) had TN. Most frequent regimen for first- or second-line CT was eribulin (ERI) (88.9%) among patients who received second-line CT. Frequent sequences were oral fluorouracil (FU) followed by ERI (18.3%), bevacizumab/paclitaxel (Bev/PTX) followed by ERI (13.5%), and ERI followed by Bev/PTX (11.1%). Patients who received taxanes as first-line CT had significantly more adverse event discontinuation than those with oral FU or ERI (p < 0.01).
Conclusions
In this real-world setting, ERI was administered in almost all first- or second-line regimens and taxane-based regimens were associated with more adverse event discontinuations. We intend to further investigate overall survival among CT sequences, as well as progression-free survival, new metastasis-free survival, type of progression and QoL.
Clinical trial identification
NCT02551263.
Legal entity responsible for the study
Masakazu Toi.
Funding
Eisai.
Editorial Acknowledgement
Disclosure
All authors have declared no conflicts of interest.