Treatment Efficacy

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.

The goal of this observational study is to identify the characteristics of brain functional connectivity in refractory constipation and fluoxetine-sensitive patients. The main questions it aims to answer are: * Investigating the alterations in brain functional connectivity in patients with refractory constipation and fluoxetine-sensitive patients * Assessing the predictive value of brain functional connectivity regarding the efficacy of fluoxetine and standard protocol treatments for constipation. Participants will receive: * Standard physiological and psychological assessments of constipation * BOLD-fMRI tests * Standard protocol and fluoxetine treatment If there is a comparison group: Researchers will compare: Refractory group/Fluoxetine sensitive group to see the specific brain alterations.