• Voluntarily participate and sign the informed consent form

• Aged over 18 years old, regardless of gender;

• Locally advanced or metastatic breast cancer confirmed by histopathology;

• Received ≥2 previous lines of anti-tumor treatment and developed resistance to standard treatment;

• Life expectancy ≥3 months;

• ECOG performance status 0 to 2;

• Have measurable or/and evaluable lesions (non-radiotherapy target areas) (lesion evaluation is based on Recist1.1 standards);

• No serious organ (main organ: heart, lung, liver, kidney) functional abnormalities (refer to respective standards);

• Routine blood test: white blood cells (WBC) ≥3 × 109/L; absolute neutrophil count (ANC) ≥1.5 × 109/L; platelets (PLT) ≥100 × 109/L; hemoglobin (Hgb) ≥8g /dL;

⁃ Blood biochemical indicators: AST (SGOT), ALT (SGPT) ≤ 2.5 × upper limit of normal value (ULN) (in the case of no liver invasion) or ≤ 5 × upper limit of normal value (ULN) (in the case of liver invasion) Bottom); total bilirubin (TBIL) ≤ ULN; serum creatinine clearance calculated according to the CG formula \> 30 mL/min

⁃ Coagulation function: prothrombin time (PT), international normalized ratio (INR) ≤ 1.5 × ULN (unless warfarin is being used for anticoagulation);

⁃ Able to comply with the research visit plan and other program requirements;

⁃ All patients of childbearing age must agree to take effective contraceptive measures during the study and within 6 months of stopping treatment. Female patients of childbearing age must have a negative urine pregnancy test before treatment.

‣ Subjects must meet all of the following additional criteria to be included in the OGPT group:

• No absolute contraindications to tissue-invasive procedures required to obtain organoid cultures。

• Sufficient tissue can be provided for organoid culture: biopsy samples (length \>1cm, 3 strips), surgical resection samples (total volume \>1cm3, weight \>0.2g), thoracentesis, abdominal puncture, pericardiocentesis and other malignant effusion samples (pleural effusion \>500mL, ascites \>500m) and confirmed to contain malignant tumor cells.