Rituximab (anti-CD20 monoclonal antibody) for the treatment of patients with clonal lymphoproliferative disorders after orthotopic liver transplantation: a report of three cases

Background/Aims: Post-transplant lymphoproliferative disorders (PT-LPD) are a well-known complication of organ transplantation. Their incidence after liver transplantation in adults ranges from 1.8 to 4%. Reduction of immunos uppression led to remission in a few cases, Other treatments include chemot herapy, interferon alpha therapy and/or intravenous-immunoglobulins, or ant iviral drugs, However, monoclonal antibodies directed against B-cell specif ic antigens have rarely been used in those patients, Our aim was to study t he feasibility and efficacy of Rituximab, a new, promising human chimeric a ntibody that recognizes the CD20 antigen, for the treatment of patients wit h clonal lymphoproliferative disorders after orthotopic liver transplantati on. Methods: Rituximab (IDEC-C2HB8; Roche Laboratories, Neuilly-sur-Seine, Pran ce) was administered at a 375 mg/m(2) dose on days 1, 8, 15, and 22, in an outpatient setting, in three patients with PT-LPD. The tumor was classified as polymorphic PT-LPD in two cases and PT-LPD with features of large cell lymphoma in one case, All the tumors expressed the CD20 antigen and were EB V-related, and the clonality was confirmed in all three cases, The 4 inject ions of the anti-CD20 monoclonal antibody were associated with reduced immu nosuppression in the three patient. Results: The treatment with Rituximab was well tolerated without any side e ffects, The two patients with polymorphic PT-LPDs underwent rapid complete remission, whereas the treatment modalities were ineffective in the patient with the large-cell non-Hodgkin-lymphoma. Conclusion: These results must be confirmed in a larger cohort of liver tra nsplant recipients suffering from lymphoproliferation, However, they indica te rapid efficiency of Rituximab in association with reduced immunosuppress ion in these disorders.