Age

18–any

Sex

FEMALE

Healthy volunteers

Not accepted

Signed written informed consent prior to enrollment
Age ≥ 18 years
ECOG PS score 0-1
Newly diagnosed T1c N1-2 or T2-3 N0-2 breast cancer
Triple-negative breast cancer with PD-L1 CPS \< 10
Hemoglobin ≥ 10.0 g/dl, neutrophils ≥ 1.5 × 10⁹/L, platelet count ≥ 100 × 10⁹/L
BUN ≤ 1.5 × upper limit of normal (ULN), creatinine ≤ 1.5 × ULN
Serum bilirubin ≤ 1.5 × ULN, alkaline phosphatase (AKP), AST, and ALT ≤ 2.5 × ULN
Women of childbearing potential must be willing to use contraception during the study
Negative serum or urine pregnancy test within 7 days prior to treatment

Occult breast cancer
Bilateral breast cancer
Breast tumor unsuitable for SBRT
Unable to undergo MRI scanning
History of other malignancies that may affect survival
Active autoimmune disease or history of autoimmune disease
Current use of immunosuppressants or systemic steroids (within 2 weeks prior to enrollment)
Known allergy to any component of the investigational drugs
Uncontrolled cardiac symptoms or diseases
Active infection or unexplained fever \> 38.5°C during screening/before first dose
Other factors likely to cause early study termination (e.g., serious concurrent illnesses, significant lab abnormalities, or social/family circumstances affecting safety/data collection)

Neoadjuvant Treatment of Triple-Negative Breast Cancer with Stereotactic Radiotherapy, PD-1 Monoclonal Antibody, and Chemotherapy