A Single-arm, Prospective Phase Ⅱ Clinical Study of Utidelone Combined With Capecitabine in the Treatment of Active Brain Metastasis of TNBC

Inclusion Criteria: 1. Age ≥18 years old; 2. Invasive breast cancer confirmed by histological or cytological examination, accompanied by metastatic disease; Patients with metastatic diseases not confirmed by pathology or cytology should obtain clear evidence of metastasis through physical examination or radiological research; 3. Based on the pathological report of recent biopsy or other pathological specimens (confirmed by the laboratory of the participating research center), the histology and/or cytology are confirmed as triple negative breast cancer. The specific requirements include: a) the definition of negative human epidermal growth factor receptor 2(HER2): the immunohistochemistry (IHC) is 0 or 1+; If IHC was 2+, it was confirmed negative by fluorescence in situ hybridization (FISH). B) Negative estrogen and progesterone receptors means that IHC examination shows ER \< 10% and or PR \< 10%, and the researcher evaluates that patients cannot benefit from endocrine therapy. 4. Newly diagnosed brain metastases or brain metastases that have progressed after local treatment: patients with brain metastases who met all the criteria of this scheme before starting from September 1, 2023 and did not meet all the exclusion criteria can also be included; 5. Patients must have measurable central nervous system diseases, defined as at least one brain parenchymal lesion, which can be accurately measured in at least one dimension through local radiological examination; And there is no central nervous system symptom or symptom controllable, so radiotherapy is not needed urgently. 6. Patients who have previously received at least one taxane and/or one anthracycline antibiotic (as a treatment history of neoadjuvant therapy, adjuvant therapy or metastatic therapy or both); 7. Allow (new) adjuvant therapy to have recurrence and metastasis after stopping using Utterone and/or Capecitabine for more than one year, or stop taking drugs for non-progressive reasons in the rescue stage; 8. The physical status score (ECOGPS) of the eastern cancer cooperative group is 0-2, and the life expectancy is more than 12 weeks; 9. Normal organ and bone marrow function; Blood routine examination was basically normal within one week before joining the group (based on the normal laboratory of each research center): neutrophil count (ANC) ≥ 1.5× 109/L; Hemoglobin (HB) ≥ 90g/L; Platelet count (PLT) ≥ 75× 109/L; Liver and kidney function tests were basically normal within one week before enrollment (based on the normal values of laboratories in each research center): total bilirubin (TBIL)≤1.5× upper limit of normal value (ULN); Alanine aminotransferase (SGPT/ALT)≤2.5×ULN (patients with liver metastasis ≤ 5 XULN); Aspartate aminotransferase (SGOT/AST)≤2.5× upper limit of normal value (ULN); Creatinine clearance rate (Ccr)≥60ml/min. 10. Neuropathy should be \< grade 2 within 4 weeks before enrollment (version 5.0 of ncictcae); 11. No major organ dysfunction and no heart disease; 12. Women and male patients with reproductive potential must agree to use appropriate contraceptive measures before the start of the study and during the study participation. Exclusion Criteria: 1. Patients with extensive meningeal metastasis and brain metastasis who are ineffective in dehydration treatment with hormones or in urgent need of radiotherapy; 2. Invasive breast cancer confirmed by histological or cytological examination, accompanied by metastatic disease; Patients with metastatic diseases not confirmed by pathology or cytology should obtain clear evidence of metastasis through physical examination or radiological research; 3. Received chemotherapy, major surgery, targeted therapy or immunotherapy within 2 weeks before joining the group (the interval between targeted therapy and immunotherapy is at least 2 weeks or at least 5 half-lives, whichever is shorter); Received endocrine therapy within 1 week before joining the group; He had received nitrosourea or mitomycin chemotherapy within 6 weeks before joining the group; 4. Receive unlisted clinical trial drugs within 4 weeks before entering the group; 5. Previous history of grade 3 or 4 allergic reactions related to Utterone or Capecitabine; 6. inability to swallow, chronic diarrhea and intestinal obstruction, there are many factors that affect the taking and absorption of drugs; 7. Known contraindications for gadolinium MRI contrast agents, such as pacemakers, shrapnel or ocular foreign bodies; 8. Suffering from other malignant tumors in the past 3 years, excluding cured cervical carcinoma in situ, basal cell carcinoma of skin, squamous cell carcinoma of skin or early thyroid carcinoma; 9. Seizures occurred more than 2 times within 4 weeks before joining the group; 10. Poor control of hypertension; Or have a history of hypertensive crisis or hypertensive encephalopathy; 11. Have a history of bleeding in the central nervous system of grade 3 or above within 12 months; 12. Suffering from serious or uncontrollable diseases, including but not limited to: 1) active virus infection, such as HIV and HBV active phase (HbsAg positive and HBV-DNA≥103, hepatitis C antibody positive); 2) Suffering from severe cardiovascular disease in the past: uncontrollable hypertension; Myocardial infarction, unstable arrhythmia, congestive heart failure, pericarditis, myocarditis, etc. According to NYHA criteria, patients with grade Ⅲ \~ Ⅳ cardiac insufficiency, or those with left ventricular ejection fraction (LVEF) less than 50% indicated by echocardiography; 12. Suffering from serious or uncontrollable diseases, including but not limited to: 1) active virus infection, such as HIV and HBV active phase (HbsAg positive and HBV-DNA≥103, hepatitis C antibody positive); 2) Suffering from severe cardiovascular disease in the past: uncontrollable hypertension; Myocardial infarction, unstable arrhythmia, congestive heart failure, pericarditis, myocarditis, etc. According to NYHA criteria, patients with grade Ⅲ \~ Ⅳ ca