Diagnostic Qualities of the Positron Emission Tomography Coupled to the Scanner (PET / CT) in the Assessment of Response to Non-Hodgkin's Lymphoma Therapy in Children and Adolescents

This is a diagnostic prospective multicenter study. This study will be conducted in 32 centers of the Société Française des Cancers et Leucémies de l'Enfants et de l'Adolescent (SCFE) in patients with non-Hodgkin lymphoma and treated according to recommendations of the SFCE for each type of non-Hodgkin lymphoma. All patients will have a PET / CT associated with conventional imaging time of remission assessment. Histological examination of residual tumor will be conducted whenever practicable in patients with pathologic residual image on conventional imaging and / or PET / CT. A central review of conventional imaging examinations and PET / CT will be performed independently from each other. Moreover, whenever possible, patients will have a PET / CT at diagnosis and an early PET / CT (between J8 and J28 according to the type of lymphoma and toxicities due to treatment). The results of the early PET / CT should not lead to treatment modifications. In case of residual tumor at remission assessment, therapeutics changes as recommended therapeutic protocols will be based on histologic findings and not on the results of PET / CT alone.