Intrathecal Trastuzumab Administration in Metastatic Breast Cancer Patients Developing Carcinomatous Meningitis

Inclusion Criteria: * Metaplastic Infiltrating adenocarcinoma of the breast * HER2 Overexpression by IHC and / or amplification (FISH and or ICHS) * Positive diagnosis of neoplastic meningitis: positive CSF cytology (obtained within 28 days before inclusion) AND / OR clinical symptoms of neoplastic meningitis and aspect of tumoral meningitis on MRI * Brain metastases are allowed without prior treatment, if they are asymptomatics and without engagement. In cases of symptomatic brain metastases, subjects could be included only if surgery and / or radiotherapy (stereotactic or in toto) were performed and if the cerebral metastatic localization allow IT or intra-ventricular treatment. The last radiotherapy session or the surgery must have been done 3 weeks before. * Aged 18 years old or more * Male and female * Life expectancy more than 2 months * Satisfactory Cardiac function: left ventricular ejection fraction (LVEF) determined by ultrasound scan or myocardial scintigraphy * Adequate Biological functions 14 days before inclusion, according to the criteria below: Neutrophils \> 1.0 x 109/L, Hemoglobin \> 9.0 g/dL (+ transfusion if needed,Platelets \> 50 x 109/L,Bilirubin \< 3 x N, ALT \& AST \< 10 x N, Creatinine \< 2.0 mg/dL, Clearance \> 25 mL/min (Cockcroft and Gault formula), Prothrombin time \> 70 %, Kaolin cephalin coagulation time \< 1.5 x N. * Women of childbearing potential, must take adequate birth control measure during the study period and must have a negative pregn…