Predictive Model of Axillary Nodal Status After Neoadjuvant Chemotherapy in Breast Cancer Patients

Study Overview
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Brief Summary
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The management of patients diagnosed with breast cancer (BC) with axillary nodal involvement is still a controversial topic. These patients' treatment usually involves the administration of a neoadjuvant chemotherapy (NAC) in order to improve survival rates and increase local disease control. Depending on the tumor subtype, an axillary pathologic complete response (pCR) is achieved in 40-70% of initially axillary node-positive patients (cN+). Concerning patients with an axillary pCR, thus a clinically negative node status (cN0), axillary lymphadenectomy (ALND) might be replaced by less invasive surgical approaches and sentinel lymph node biopsy (SLNB) is considered, in these cases, an effective alternative treatment. However, the relatively high false negative rates, reported in several validation trials, points out the complexity concerning these patients' treatment. Moreover, histological findings' predictive and prognostic value, after SLNB, of micrometastases and isolated tumor cells (ITCs) is still unclear. Currently, dual-tracer-guided lymph node biopsy and the surgical removal of ≥ 3 sentinel lymph nodes are known as effective strategies aimed to reduce the false negative rates. There are several ongoing clinical trials to understand and define the best approach for these patients. Nowadays, there's great interest in potential prognostic role of systemic inflammation's biochemical markers such as neutrophil-to-lymphocyte ratio (NLR). Systemic inflammation's markers may be nodal pCR's predictors after NAC in node-positive breast cancer patients. The aim of the study is to develop and validate a pre-operative model, able to predict pCR after NAC to select the patients suitable for a surgery de-escalation strategy.

Detailed Description
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This is a retrospective, observational, multicentric and no profit study. The study involves patients with diagnosis of cN+ breast cancer who underwent neoadjuvant treatment and then treated with lymph node biopsy or axillary lymphadenectomy, referring to the participating centers. For each patient the following clinical-anamnestic information will be collected: age, pre-NAC blood cell count, tumor dimension, clinical staging (cT, cN), histological information (tumor subtype, grading, receptors' status, Ki-67 value), neoadjuvant treatment regimen, clinical and radiological local response after NAC, clinical and radiological nodal response after NAC, type of surgery, number of examined lymph nodes, number of positive lymph nodes, pathological staging after surgery (ypT, ypN).

Official Title
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Retrospective, Observational, Multicentric Study Aimed at Developing a Model for Prediction of Axillary Lymph Node Status After Neoadjuvant Chemotherapy in Breast Cancer Patients

Conditions
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Breast Cancer

Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Diagnosis of breast cancer confirmed by histological examination Patients who underwent neoadjuvant chemotherapy Axillary lymph nodes involvement at diagnosis (cN≥1), identified by clinical examination and/or imaging techniques and/or axillary lymph node cytology aspirate positive for breast cancer cells. Exclusion Criteria: Patients with M+ at diagnosis Contraindications for neoadjuvant chemotherapy

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 90 Years

Sexes Eligible for Study
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Female

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

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Patients with diagnosis of cN+ breast cancer who underwent neoadjuvant treatment<br>Patients with diagnosis of cN+ breast cancer who underwent neoadjuvant treatment and then treated with lymph node biopsy or axillary lymphadenectomy | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Selection of features | Identification of pre-operative clinical-pathological features predictive for ypN0 status after NAC in patients with cN+ breast cancer (Logistic regression model will be performed) | 48 months | 
| Nomogram | Development and validation of a nomogram, based on selected clinical-pathological features, able to predict nodal status after neoadjuvant chemotherapy | 48 months |