This study is a real-world study. we collected patients with advanced HER2-negative breast cancer previously treated with antibody-drug conjugates, and received eribulin mesylate-based therapy post-ADC. We retrospectively collect the data on previous systemic treatment, and prospectively collect the treatment data of the therapeutic regimens based on eribulin mesylate.
At least 18 years old;
Inoperable locally advanced or metastatic breast cancer;
Planning to use a single-agent or combination treatment regimen based on eribulin;
HER2 negative (IHC 0,+, or ++ but ISH negative);
HER2-positive tumors
The hormone receptor status is unknown;
Patients who have received eribulin treatment before;
Those who have had other malignant tumors within the past 5 years (excluding the following situations: cured skin basal cell carcinoma, cervical carcinoma in situ, papillary thyroid carcinoma; second primary cancer that has been cured and has no recurrence within 5 years; subjects who have clearly identified the origin of the metastatic lesion as being from a certain primary tumor);