Targeted Axillary Dissection After Neo-adjuvant Chemotherapy

Study Overview
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Brief Summary
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Currently most breast cancer patients with confirmed axillary lymph node metastasis (cN1) at diagnosis are candidates for neoadjuvant chemotherapy (NAC). The increased utilization of NAC can be attributed to practical clinical advantages. The increasing use of NAC has, however, introduced questions regarding appropriate loco-regional management, including the optimal surgical approach to the axillary lymph nodes. According to current guidelines, patients presenting with cN1 disease and treated with NAC, still undergo axillary lymph node dissection (ALND). In forty percent of these patients, however, the investigators see a nodal complete pathological response (ypN0). In certain subgroups, triple negative breast cancer and Her2 amplified breast cancer, this percentage is even higher. The investigators would like to lessen surgical morbidity by performing a targeted axillary dissection. The investigators place a clip in the biopsy-proven lymph node metastasis at diagnosis. After NAC, the investigators perform a dual agent sentinel node procedure and remove the clipped node during the same surgery. When these lymph nodes are microscopically tumor-free, the investigators can abolish an ALND. Targeted axillary dissection after NAC for cN1 disease seems to have acceptable false negative rates in previous trials. The investigators would like to further define patients where an ALND can be safely omitted.

Official Title
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Feasability Study of a New Technique of Axillary Evaluation in Patients With Node Positive Breast Cancer Following Neo-adjuvant Chemotherapy

Conditions
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Breast Cancer

Intervention / Treatment
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* Procedure: TAD (Targeted Axillary Dissection)


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients diagnosed with cT1-3N1M0 breast cancer, histopathologically confirmed. Age greater than or equal to 18 years and less than or equal to 85 years. Necessity and agreement to neoadjuvant chemotherapy Exclusion Criteria: Previous surgery ipsilateral axillary or radiation ipsilateral axillary / chest. Extranodal metastases M1 cN2-3 status Breast cancer with direct invasion of chest wall and / or skin cT4 Disease progression (clinical /radiological) under neoadjuvant treatment Pregnancy Presence of a pacemaker in the ipsilateral chest wall

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 85 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Intervention/Treatment |
| --- |
|Procedure: TAD (Targeted Axillary Dissection)|Dual agent SLNB + resection of proven lymph nodes metastasis marked with clip at diagnosis|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Feasibility of new surgical technique TAD using Magseed | Succesful retrievement of sentinel node and clipped node | 90 minutes | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Correlation between ITC/ micrometastasis / macrometastasis in retrieved TAD nodes and number of additional lymph node metastasis in ALND |  | Two weeks |