Neoadjuvant Toripalimab Combined With Preoperative Radiotherapy for Initial Chemotherapy-Nonresponding Triple-Negative Breast Cancer Patients (NEOTRIO-2)
The goal of this clinical trial is to test whether a rescue strategy can turn chemotherapy-resistant triple-negative breast cancer (TNBC) into a curable state. Patients whose tumors fail to shrink after 2 cycles of standard neoadjuvant chemotherapy will receive a short, high-precision course of stereotactic body radiotherapy (SBRT, 24 Gy in 3 daily fractions) to the breast primary tumor, followed by 4 cycles of toripalimab (an anti-PD-1 antibody) combined with albumin-bound paclitaxel plus carboplatin. The main questions are: Can this SBRT-immuno-chemo triplet raise the pathologic complete response (pCR; no invasive cancer in breast or nodes at surgery)? Can it produce an objective radiologic response (ORR) in at least half of the patients, allowing more breast-conserving operations and fewer mastectomies? Secondary objectives include safety, changes in tumor-infiltrating lymphocytes (TILs), event-free survival, and exploratory biomarkers (whole-exome and RNA-seq, PBMC immunoprofiling) to discover signatures of benefit. Participants will undergo image-guided core biopsies before and after SBRT, provide serial blood samples, and have definitive surgery 3-5 weeks after the last cycle.
• Female, age 18-75 years, newly diagnosed invasive breast cancer.
• Histologically confirmed triple-negative phenotype: ER \< 1 %, PR \< 1 % by IHC, HER2 negative (IHC 0/1+ or IHC 2+ with ISH negative).
• Clinical stage II-III (T2-4 or N1-3, M0).
• Completed 2 cycles of standard neoadjuvant chemotherapy (taxane ± anthracycline ± platinum) and assessed as non-responder: stable disease (SD) or progressive disease (PD) by RECIST 1.1.
• ECOG performance status 0 or 1.
• Radiation oncologist confirms suitability for SBRT and subsequent standard post-operative radiotherapy.
• Adequate organ function within 14 days before enrollment: WBC ≥ 2 000/µL, ANC ≥ 1 500/µL, platelets ≥ 100 000/µL, Hb ≥ 9 g/dL; Serum creatinine ≤ 2 mg/dL or GFR ≥ 40 mL/min; AST/ALT ≤ 2.5 × ULN, total bilirubin ≤ ULN (≤ 3 mg/dL if Gilbert syndrome); INR ≤ 1.5 (on anticoagulation allowed if therapeutic range)
• Negative HIV, HBV surface antigen, and HCV antibody (or HBV DNA / HCV RNA negative if false-positive).