Biological Response to Tamoxifen (TAM) in Patients With Breast Cancer Non Metastatic RH+

Inclusion criteria

• Adult Females (≥ 18 years), with effective contraception. The contraceptive should not use estrogen to a derivative. It must be continued during treatment with tamoxifen for at least two months after his arrest.
• Histologically confirmed diagnosis of invasive breast cancer, previously untreated. Patients have been supported for a breast cancer may be included if a period of at least 2 years between the last systemic treatment of inclusion in the study.
• Primary tumor hormonopositive: ER and / or PR ≥ 50% by immunohistochemistry.
• Lack of HER2 overexpression
• Palpable primary tumor or greater than or equal to 20 mm in diameter, measured by ultrasound
• Patient scheduled to undergo breast cancer surgery
• No metastases
• Clinical Stage M0
• Performance index ≤ 1 (OMS)
• Neutrophils WBC > or = 1500 / mm3, Platelets > or = 100 000/mm3 Hemoglobin ≥10 g/dL
• Normal liver function: bilirubin ≤ 1.5 x ULN, aspartate aminotransferase (AST) and alanine aminotransferase (ALT) ≤ 2.5 x ULN (≤ 5 x ULN if liver metastases).
• Normal renal function (creatinine ≤ 1.5 mg / dL or creatinine clearance ≥ 60 mL / min)
• Cardiac function (MUGA scan or ultrasound February> 55%) and lung function, 5.2.2 Criteria related to participation in the study:
• Patient affiliated to social security, Patient has signed and dated consent

Non-Inclusion Criteria:

• Pregnant or Breastfeeding women
• Use of St. John's Wort (herbal tea ...) within 5 days before starting treatment
• Consumption of grapefruit juice in the last 5 days of starting treatment
• Congenital galactosemia
• Glucose and galactose malabsorption
• Lactase deficiency
• Co-medications that may interfere with cytochrome P450:
• Ongoing Enzyme inducers:

• Antiepileptic drugs: carbamazepine, phenobarbital, phenytoin
• Antinfectieux: rifampin, rifabutin, névrirapine, griséofilvine, efavirenz
• Ongoing Enzyme Inhibitors:

• Inhibitors of serotonin reuptake: fluoxetine, paroxetine
• Thioridazine. Quinidine
• Amiodarone
• Ca antagonists: diltiazem, verapamil
• azole antifungals ketoconazole, fluconazole, miconazole.
• No protease inhibitors: ritonavir, nelfinavir, amprenavir, indinavir.
• Macrolides: erythromycin, clarithromycin, josamycin