UFT/LV Maintenance Vs Observation in Metastatic Breast Cancer Responsive to Chemotherapy

Inclusion Criteria: * metastatic breast cancer * objective response or stabilisation after 6 to 8 cycle of a first line chemotherapy * time period between the end of chemotherapy and randomization \< 4 weeks * age over 18 years * Performance status (OMS) \< 2. * Life expectancy \> 3 months * Biological criteria before randomization: Neutrophiles \> 1.5 x 109 G/L; Pl. \> 100 x 109 G/L; Hb \> 10 g/dl; Creatininemia \< 1,5 UNL; Bili. \< 2 UNL; Transaminases \< 2,5 UNL; Alcalines Phosphatases \< 2,5 UNL * Signed written informed consent Exclusion Criteria: * Metastatic breast cancer having received more than one chemotherapy line. * Tumor progression under chemotherapy * Free interval between primary tumor and metastases \> 5 years, with estrogen receptors and without visceral metastases * Free interval between primary tumor and metastases \< 18 months after adjuvant chemotherapy if first lime chemotherapy only led to a tumor stabilization * Concomitant hormonotherapy * Other cancer * Symptomatic brain metastases * Any uncontrolled severe disease except breast cancer (especially cardiac failure with LVEF \< 50% or coronary insufficiency * Psychiatric disorder * Other concomitant trial * Male patient * Pregnancy and breast-feeding (effective contraception is mandatory in the case of women of child-bearing potential) * History of high dose chemotherapy with bone marrow transplantation