Clinical Exploratory Study on Predicting Drug Sensitivity for Breast Cancer Treatment Using Simulated Organoid Models.

1. Inclusion and Exclusion Criteria for Early - stage Breast Cancer 1.1 Inclusion Criteria Age between 18 and 70 years old, regardless of gender. ECOG score: 0 - 1. Clinically diagnosed or pathologically confirmed as breast cancer. TNM stage is T2 - 3 and Nx, and is currently receiving or planning to receive subsequent neoadjuvant therapy (including but not limited to chemotherapy, targeted therapy, endocrine therapy, etc.). According to the Response Evaluation Criteria in Solid Tumors (RECIST 1.1), there is at least one measurable lesion; the expected survival time is ≥ 12 weeks. The subject must recover from all toxicities caused by previous treatments (recovery to ≤ grade 1, evaluated based on CTCAE 5.0, or meet the inclusion criteria of the protocol), except for alopecia, vitiligo, or hypothyroidism that remains stable after hormone replacement therapy. (Note: For subjects with some chronic and stable grade 2 toxicities that the researcher deems related to previous anti - tumor treatments (such as chemotherapy - induced neuropathy), a decision on whether to include the subject in this study will be made after discussion with the medical monitor.) For female subjects with child - bearing potential and male subjects whose partners have reproductive potential, effective medical contraceptive measures should be taken during the research treatment period and within 6 months after the end of drug administration. Voluntarily sign the informed consent form, and be willing and able to comply with the follow - up, treatment, laboratory tests, and other research requirements specified in the research schedule. 1.2 Exclusion Criteria Central nervous system (CNS) metastasis or carcinomatous meningitis. Bilateral breast cancer. History of ductal carcinoma in situ (DCIS) or lobular carcinoma in situ (LCIS). History of invasive breast cancer or metastatic breast cancer. Arterial or venous thrombosis events, such as deep vein thrombosis and pulmonary embolism, occurred within 3 months before randomization. Positive human immunodeficiency virus (HIV) test or history of acquired immunodeficiency syndrome (AIDS); known active syphilis infection. Other serious diseases that are judged to potentially affect follow - up and short - term survival of the patient. Inability to swallow, chronic diarrhea, and intestinal obstruction, with various factors affecting drug intake and absorption. Known allergy to the potentially used treatment drugs. Adverse reactions of grade ≥ 1 that are still ongoing due to previous treatments. Exceptions are alopecia or cases that the researcher deems should not be excluded. Such cases should be clearly recorded in the investigator's notes. Female patients who are pregnant, breastfeeding, or planning to become pregnant during the study period (pregnancy tests should be considered for sexually active women of child - bearing age). Having had other malignancies within the past 5 years, excluding cured cervical carcinoma in situ, basal cell carcinoma of the skin, or squamous cell carcinoma of the skin. Urinalysis shows urine protein ≥ 2+ or confirmed 24 - hour urine protein quantification \> 1.0g; presence of any autoimmune diseases that still require treatment or a history of autoimmune diseases, excluding hypothyroidism caused by autoimmune thyroiditis that only requires hormone replacement therapy and type 1 diabetes with controllable and stable blood sugar. Patients with hypertension that cannot be well - controlled with a single antihypertensive drug (systolic blood pressure \> 140 mmHg, diastolic blood pressure \> 90 mmHg); history of unstable angina pectoris; newly diagnosed angina pectoris within 3 months before screening or myocardial infarction event within 6 months before screening; arrhythmia (including QTcF: ≥ 450 ms for men and ≥ 470 ms for women) requiring long - term use of anti - arrhythmic drugs and New York Heart Association class ≥ II heart failure. Other situations that researchers evaluate as potentially endangering the patient's safety or having poor compliance, such as having serious diseases (including mental diseases), severely abnormal test results, and other high - risk factors in the family or society. 2. Inclusion and Exclusion Criteria for Advanced - stage Breast Cancer 2.1 Inclusion Criteria Age between 18 and 70 years old, both men and women are eligible. ECOG score: 0 - 1. Clinically or pathologically clearly diagnosed as advanced - stage breast cancer, regardless of molecular subtype. Currently receiving or planning to receive anti - tumor drug treatment, regardless of the number of treatment lines. According to the Response Evaluation Criteria in Solid Tumors (RECIST1.1), there is at least one measurable lesion; the expected survival time is ≥ 12 weeks. The subject must recover from all toxicities caused by previous treatments (recovery to ≤ grade 1, evaluated based on CTCAE5.0, or meet the inclusion criteria of the protocol), except for alopecia, vitiligo, or hypothyroidism that remains stable after hormone replacement therapy. (Note: For subjects with some chronic and stable grade 2 toxicities that the researcher deems related to previous anti - tumor treatments (such as chemotherapy - induced neuropathy), a decision on whether to include the subject in this study will be made after discussion with the medical monitor.) For female subjects with child - bearing potential and male subjects whose partners have reproductive potential, effective medical contraceptive measures should be taken during the research treatment period and within 6 months after the end of drug administration. Voluntarily sign the informed consent form, and be willing and able to comply with the follow - up, treatment, laboratory tests, and other research requirements specified in the research schedule. 2.2 Exclusion Criteria Central nervous system (CNS) metastasis or carcinomatous meningitis. History of gastrointestinal perforation or fistula within half a year before medication or having a high bleeding risk. Positive human immunodeficiency virus (HIV) test or history of acquired immunodeficiency syndrome (AIDS); known active syphilis infection. Other serious diseases that are judged to potentially affect follow - up and may lead to short - term survival of the patient. Inability to swallow, chronic diarrhea, and intestinal obstruction, with various factors affecting drug intake and absorption. Known allergy to the potentially used treatment drugs. Adverse reactions of grade ≥ 1 that are still ongoing due to previous treatments. Exceptions are alopecia or cases that the researcher deems should not be excluded. Such cases should be clearly recorded in the investigator's notes. Pregnant or breastfeeding women (pregnancy tests should be considered for sexually active women of child - bearing age). Having had other malignancies within the past 5 years, excluding cured cervical carcinoma in situ, basal cell carcinoma of the skin, or squamous cell carcinoma of the skin. Occurrence of abdominal fistula, gastrointestinal perforation, or abdominal abscess within 28 days before participating in this study. Urinalysis shows urine protein ≥ ++ or confirmed 24 - hour urine protein quantification \> 1.0g. Patients with hypertension that cannot be reduced to the normal range with antihypertensive drugs (systolic blood pressure \> 140mmHg, diastolic blood pressure \> 90mmHg). Other situations that researchers evaluate as potentially endangering the patient's safety or having poor compliance, such as having serious diseases (including mental diseases), severely abnormal test results, and other high - risk factors in the family or society. 3. Criteria for Sample Exclusion If a test sample meets any of the following criteria, it must be excluded: Samples with unsuccessful PDO culture. Samples contaminated or failed due to improper operation during the test. Samples with lost data. Samples from patients who withdraw their informed consent and do not want to leave their samples.