Number of subjects required 60 patients with significant uptake on FDG-PET imaging after neo-adjuvant chemotherapy (75 pre-inclusion) will be included. Only half of these 60 patients (30) are expected to be definitely eligible with F-miso PET identifying hypoxic areas. Out these 30 eligible patients, we assume that 5 will not be evaluable, so that a total of 25 evaluable patients will be assessable.