OncoMatch/Clinical Trials/NCT07829848
Response-Adapted Omission of Nodal Boost In N3 Breast Cancer After Neoadjuvant Systemic Therapy
Official title: Omitting the Boost to Initially Involved But Undissected Nodal Stations That Achieved Clinical Complete Response After Neoadjuvant Systemic Therapy in cN3 Breast Cancer: A Phase III Randomized Study
Is NCT07829848 recruiting? Yes, currently enrolling (Oct 2026). This NA trial studies non-drug interventions for breast cancer.
Background Clinical N3 (cN3) breast cancer represents a high-risk subgroup of locally advanced disease. After neoadjuvant systemic therapy (NST), patients who achieve a clinical complete response (cCR) in initially involved but undissected nodal stations currently receive a boost to these regions as part of standard postoperative radiotherapy. However, whether this boost is necessary in this setting remains unknown, and prospective evidence on the safety of boost omission is lacking. Objective The REACT-N3 trial aims to evaluate whether omitting the boost to undissected nodal stations that achieve cCR after NST is non-inferior to standard boost in terms of 3-year invasive breast cancer recurrence-free interval (IBCRFI), while reducing toxicity to adjacent organs. Methods This is an open-label, multicenter, randomized phase 3 trial. Eligible patients are women with cN3 breast cancer who have completed NST, undergone breast/axillary surgery with the internal mammary, supraclavicular, and infraclavicular nodes left undissected, and have no macroscopic residual disease in these stations on post-NST \[¹⁸F\]FDG PET-CT or other imaging. Participants will be randomized 1:1 to receive either a standard boost (10 Gy in 5 fractions) or no boost to the initially involved but cCR-converted undissected nodal stations. Randomization is stratified by postoperative axillary nodal status (ypN- vs. ypN+), location of the involved nodal station (SCV vs. non-SCV), and molecular subtype (TNBC vs. non-TNBC). The primary endpoint is 3-year IBCRFI. Secondary endpoints include locoregional recurrence-free survival, distant metastasis-free survival, disease-free survival, overall survival, toxicity, and patient-reported outcomes. With a non-inferiority margin of 8%, a one-sided α of 0.05, 80% power, and 10% drop-out rate, a total of 534 patients will be enrolled. Discussion The REACT-N3 trial will provide high-level evidence on the safety of boost omission in cN3 breast cancer patients with cCR after NST. If non-inferiority is confirmed, this strategy could establish a new, toxicity-sparing standard for regional nodal irradiation in this high-risk population.
Check if I qualifyExtracted eligibility criteria
Cancer type
Breast Carcinoma
Disease stage
Required: Stage CN3 (other)
Excluded: Stage IV
cN3 disease, defined according to AJCC 8th staging system, confirmed by imaging and/or pathology
Performance status
ECOG 0–1(Restricted strenuous activity)
Demographics
Prior therapy
Must have received: neoadjuvant systemic therapy
Completion of NST. Standard-of-care regimens must include at least four cycles of chemotherapy; Anti-HER2 targeted therapy is mandatory for HER2-positive disease, and immunotherapy may be added for eligible triple-negative breast cancer (TNBC). Clinical trial regimens are permitted per protocol, with or without chemotherapy, including novel agents (e.g., antibody-drug conjugates [ADCs], immunotherapies, anti-angiogenics, PARP inhibitors, or other investigational drugs). Both pathways are accepted provided the full protocol-specified course is completed.
Cannot have received: radiotherapy to the breast, chest wall, or regional nodes
Prior radiotherapy to the breast, CW, or regional nodes
Structured fields extracted by AI. May contain errors — verify against the official protocol.
Frequently asked questions
Is NCT07829848 currently recruiting?
Yes, this trial is currently recruiting patients.
Are there prior therapy exclusions?
Yes. Prior radiotherapy to the breast, chest wall, or regional nodes disqualifies patients from enrollment.
What disease stage is eligible?
Stage CN3 is required.
Is there an age limit?
Yes. Patients must be 75 years or younger.
Could you qualify for this trial?
Enter your biomarker results to see how this trial's eligibility criteria match your specific cancer profile.
Check if I qualifyRelated pages