In addition, other 250 samples from relapsing/refractory patients will be included in 2 years. Of these 250 samples form relapsing/refractory patients, it is expected that 150 samples will be drawn from patients in whom the sample was already analyzed at diagnosis in the current study, and 100 samples will be drawn form 100 additional patients that were not previously included in the study at the initial diagnosis. So, the expected distribution of analyzed samples will be: 450 at diagnosis, 150 resampling at first relapse from patients already analyzed at diagnosis, and 100 samples at first or subsequent relapse from patients not included in the study at the time of diagnosis. The investigator expect at least 500 patients and 700 samples.