RecruitingDiagnostic testMultilayer Biological Characterization of Advanced Follicular Lymphoma: a Translational Study From FIL_FOLL12 TrialThis is a Multicenter, Retrospective, Biological study ancillary to FOLL12 trial to evaluate the role of EZH2 aberrations in patient with FL treated with immunochemotherapy. Moreover, several novel biomarkers of FL will be investigated.