Molecular Subtyping of Breast Cancer-derived Small Extracellular Vesicles (sEVs) to Predict Therapeutic Efficacy: An Exploratory, Single-Center, Phase II Clinical Study
The goal of this observational study is to learn if a new diagnostic test using specific labels for breast cancer sEVs on a microchip can accurately diagnose the molecular subtypes in patients with breast cancer. The main questions it aims to answer are: * What is the sensitivity of this new sEVs-based panel for diagnosing breast cancer molecular subtypes? * What is the specificity of this new sEVs-based panel for diagnosing breast cancer molecular subtypes? Researchers will compare the results from the new sEVs panel to the results from the standard pathological diagnosis to see if the new panel is accurate and reliable. Participants will be asked to: * Provide blood samples and tissue samples. * Allow researchers to access their clinical data, such as their diagnosis, treatment information, and outcomes.
• Age 18-75 years (inclusive)
• ECOG performance status 0-1
• Life expectancy ≥3 months
• Unresectable or metastatic breast cancer
• Core needle biopsy of recurrent/metastatic lesions is ongoing or planned before initiating new treatment regimen, with provision of fresh tumor tissue specimens and collection of peripheral blood samples
• Per RECIST v1.1 criteria, at least one measurable lesion or bone-only metastases
• Adequate bone marrow reserve and organ function prior to first dose:
‣ Bone marrow reserve: Platelet count (PLT) ≥90 × 10⁹/L, absolute neutrophil count (ANC) ≥1.5 × 10⁹/L, hemoglobin ≥9 g/dL
⁃ Coagulation function: INR ≤1.5, APTT ≤1.5 × ULN
⁃ Hepatic function: Basically normal liver function, total bilirubin ≤1.5 × ULN (patients with Gilbert's syndrome may have total bilirubin ≤3 × ULN), AST and ALT ≤2.5 × ULN (if liver metastases are present, AST and ALT ≤5 × ULN)
⁃ Renal function: Serum creatinine ≤1.5 × ULN or creatinine clearance ≥50 mL/min (calculated by Cockcroft-Gault formula)
⁃ Cardiac function: Left ventricular ejection fraction (LVEF) ≥50%; QTcF ≤470 ms for females, ≤450 ms for males Able to communicate effectively with the investigator and understand and comply with all requirements of the study -