The association of the monoclonal antibody Rituximab to chemotherapy regimen of B-cell lymphoma is associated with an increase response rate and event free survival when compared to chemotherapy alone (Coiffier et al NEJM 2002). It has been observed in almost all histological type of B-cell lymphomas. No significant increase of toxicity was observed especially in the most used regimen CHOP and the association R-CHOP is a standard for most B-cell malignancies CD20 positive.