This is a prospective descriptive monocentric study whose purpose is to describe the clonal evolution of the mutational pattern in cfDNA of a cohort of patients with Diffuse Large B-Cell Non-Hodgkin Lymphomas (DLBCL) before, during and after standard treatment

To determinate and to describe the clonal evolution, 30 DLBCL cases with available matched tumor DNA and plasma will be collected and analyzed by routinely applicable next generation sequencing (NGS) at the time of diagnosis, at mid treatment, at the end of treatment and at 12 months after diagnosis.

Inclusion Criteria:

• Age up to 18 years old
• With a diagnosis formally established of DLBCL or transformed straightaway follicular lymphoma or 3B grade follicular lymphoma or Burkitt-like lymphoma
• Eligible to a treatment by immunochemotherapy like R-CHOP, R-ACVBP or R-CHOP like
• First line of treatment
• Being able to benefit from standard extension assessment ( Fluorine-18 fluorodeoxyglucose positron emission tomography (18F-FDG-PET) and bone marrow biopsy with a bone marrow aspiration)
• Written informed consent
• Tumor biopsy used for diagnosis available

Exclusion Criteria:

• Patient who cannot receive polychemotherapy like R-CHOP, R-ACVBP, or R-CHOP like
• Patient who cannot benefit from standard extension assessment and follow-up by with Fluorine-18 fluorodeoxyglucose positron emission tomography (18F-FDG-PET)
• Pregnant or breast-feeding woman
• Guardianship, curatorship
• Patient who cannot follow the medical procedures of the study for geographic, social, psychological,linguistic or physical reasons