Prognostic Impact of the Neutrophil/Lymphocyte Ratio (NLR) in the Treatment of First-line Metastatic or Locally Advanced Breast Cancer Treated With CDK4/6 Inhibitor.

Study Overview
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Brief Summary
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The impact of the inflammatory microenvironment in predicting the benefit of a CDK4/6 inhibitor in the treatment of locally advanced or first line metastatic breast cancer has not yet been studied. We propose a multicenter prospective study to confirm the prognostic value of pre-therapy NLR on progression-free survival of patients initiating treatment with a CDK4/6 inhibitor combined with hormonal therapy for locally advanced or metastatic HR-pos / HER2-neg breast cancer. We will also evaluate other markers of inflammation and their prognostic and predictive value for a better response to CDK4/6 inhibitor therapy in combination with hormone therapy in these patients. Specific blood tests (lymphocyte typing) will be performed during treatment with CDK4/6.

Detailed Description
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The impact of the inflammatory microenvironment in predicting the benefit of a CDK4/6 inhibitor in the treatment of locally advanced or first line metastatic breast cancer has not yet been studied. We propose a multicenter prospective study to confirm the prognostic value of pre-therapy NLR on progression-free survival of patients initiating treatment with a CDK4/6 inhibitor combined with hormonal therapy for locally advanced or metastatic HR-pos / HER2-neg breast cancer. We will also evaluate other markers of inflammation and their prognostic and predictive value for a better response to CDK4/6 inhibitor therapy in combination with hormone therapy in these patients. Specific blood tests (lymphocyte typing) will be performed during treatment with CDK4/6.

Official Title
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Prognostic Impact of the Neutrophil/Lymphocyte Ratio (NLR) in the Treatment of First-line Metastatic or Locally Advanced Breast Cancer Treated With CDK4/6 in

Conditions
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Breast Cancer, Metastatic Breast Cancer

Intervention / Treatment
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* Biological: Blood sampling


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients with locally advanced or metastatic HR-positive, Her2-negative breast cancer Patients who are scheduled to receive first-line metastatic CDK4/6 inhibitor therapy in combination with hormone therapy as per the marketing authorization Patients who have not received previous anti-neoplastic therapies for metastatic or advanced disease (chemotherapy, targeted therapy or hormonal therapy). However, it will be possible to have initiated 1st line hormonal therapy within 4 to 6 weeks prior to inclusion. Prior radiotherapy allowed even in metastatic disease. In case of radiotherapy treatment, side effects attributable to the treatment must be resolved. Postmenopausal patients or patients with suppressed ovarian function Patient with measurable or non-measurable disease (according to RECIST v1.1 criteria) Adequate organ and marrow function to allow prescription of CDK 4/6 inhibitor therapy Age of Patient ≥ 18 years Willingness and ability to comply with scheduled visits, treatment plan, biologic tests and other trial procedures including assessments requested for inclusion Patient affiliated with a social security plan Informed consent signed prior to any specific study-related procedures Exclusion Criteria: Men (no marketing authorization for CDK4/6 inhibitors in men in France) Previous systemic treatment for metastatic disease (chemotherapy, hormone therapy, etc.) Previous treatment with a CDK4/6 inhibitor (adjuvant or for metastatic disease) Locally advanced or relapsed breast cancer for which curative treatment would be considered Her2-positive tumor status on either the primary or relapsed tumor as defined by ASCO criteria Patient with advanced, symptomatic visceral extension who may be at risk for a potentially fatal short-term complication (visceral crisis) and who requires treatment with chemotherapy Patients who are deprived of their liberty, under guardianship, or subject to a legal protection measure or who are unable to express their consent Patients who cannot undergo the trial follow-up for geographical, social or psychopathological reasons

Ages Eligible for Study
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Minimum Age: 18 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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Design Details

Primary Purpose: Other
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Other: Blood tests<br>Realization of 4 blood tests for Lymphocyte typing (Neutrophil/Lymphocyte ratio (NLR), CD4+ and CD8+ lymphocyte counts ), during CDK4/6 treatment : before initiation of CDK4/6 treatment At 3 mois after initiation of CDK4/6 treatment At 6 mois after initiation of CDK4/6 treatment At 12 mois after initiation of CDK4/6 treatment or at early end of study | Biological: Blood sampling<br>* Blood sampling for Lymphocyte typing (Neutrophil/Lymphocyte ratio (NLR), CD4+ and CD8+ lymphocyte counts )<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Progression-free survival rate | Progression-free survival rate according to the Neutrophil/Lymphocyte (NLR) ratio. NLR cut-off set at 2.53 | At 12 months after initiation of CDK 4/6 treatment | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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CDK4/6, lymphocyte typing, Neutrophil/Lymphocyte ratio (NLR)