Prospective, Single-arm, Phase II Study of Stereotactic Radiotherapy Combined with PD-1 Monoclonal Antibody and Chemotherapy As Neoadjuvant Treatment for Triple-negative Breast Cancer

The primary aim is to evaluate the efficacy of neoadjuvant SBRT combined with PD-1 monoclonal antibody and chemotherapy in patients with triple-negative breast cancer, with the endpoint being the pCR rate-defined as the proportion of patients with no residual invasive cancer in the breast and no axillary lymph node metastasis after treatment. This is a single-arm study. Eligible participants will receive : neoadjuvant treatment consisting of SBRT followed by Envafolimab (PD-1 inhibitor), chemotherapy and immunotherapy (Envafolimab). Surgery will be performed after the last chemotherapy cycle. Pathological evaluation will assess the treatment response. Patients will receive adjuvant immunotherapy (Envafolimab) up to 1 year post-surgery.