Eribulin Suppresses New Metastases in Patients With Metastatic Breast Cancer

This study aimed to investigate the progression type of metastatic breast cancer (MBC) in patients undergoing eribulin chemotherapy.

We retrospectively investigated the cases of 66 consecutive patients with MBC who underwent eribulin chemotherapy.

A total of 15 patients (22.7%) received eribulin as a 3^rd-line or later treatment, and 17 (25.8%) received eribulin as a 1^st-line treatment. The overall response was complete response in 0 (0%), partial response in 15 (22.7%), stable disease in 27 (40.9%), and progressive disease in 24 (36.4%) patients. By the time of data cut-off, time to treatment failure (TTF) events had been observed in 60 patients (90.9%), among whom, 15 (25%) had disease progression due to NM, and 45 (75%) had disease progression due to PL. In the regimen before eribulin administration, among 49 patients, 24 (49.0%) had disease progression due to NM. Luminal-type patients and those with triple-negative breast cancer exhibited a similar tendency, i.e., the rate of NM was lower in the patients treated with eribulin. The rate of NM was lower in the patients treated with eribulin in the 1^st-line setting than that in patients treated with eribulin as a later treatment.

Eribulin has a potential antitumor mechanism to prevent new metastasis. Eribulin may be effective against both the epithelial-mesenchymal transition (EMT) process and new metastasis.