CIrCuLAting Dna ESr1 Gene Mutations Analysis

ESR1, PI3KCA and AKT extensive exon sequencing will be performed using NGS (Miseq Illumina) at the Biopathology department, Institut de Cancérologie de Lorraine (ISO15189 certified lab). Samples taken at baseline (t0), at progression (tp) and 3 months before progression (tp-3) will be systematically analyzed. The intermediate samples will be stored and kept for additional studies. Follow up assessment will be performed according to prescriber's directions.