Drug Sensitivity of Hydrothorax and Ascite Organoids from Breast Cancer

90 metastatic breast cancer patients with hydrothorax and ascitic fluid will be recruited. Baseline data, including medical history, ultrasound, and MRI records, will be collected both before and after two cycles of chemotherapy. Tumor samples from hydrothorax and ascitic fluid will be obtained and cultured to generate patient-derived organoids (PDOs). These PDOs will then be exposed to standard chemotherapeutic drugs used in breast cancer treatment. Organoid growth will be monitored post-treatment, and dose-response curves will be generated to assess drug sensitivity. To evaluate clinical outcomes, the RECIST criteria will be applied to measure tumor response in patients. Correlation analysis will be performed to determine the consistency between the treatment responses observed in the PDO models and the actual clinical outcomes of the patients.