Use of ibritumomab tiuxetan anti-CD20 radioimmunotherapy in a non-Hodgkin's lymphoma patient previously treated with a yttrium-90-labeled anti-CD22 monoclonal antibody

Ibritumomab tiuxetan is a novel radioimmunotherapeutic agent that has a high response rate in relapsed or chemotherapy-refractory CD20+ B-cell non-Hodgkin's lymphoma. Whereas chemotherapy agents can successfully be used multiple times in a given patient, there are few data on the repeated use of radioimmunotherapy in terms of efficacy or morbidity, and no reports as yet involving radioconjugates that target different antigens We report on a patient who was treated successfully with yttrium-90-labeled humanized anti-CD22 monoclonal antibody (90Y-epratuzumab). Upon relapse 3 years later, the patient was treated again with radioimmunotherapy consisting of 90Y-ibritumomab tiuxetan anti-CD20 monoclonal antibody, with a good response and acceptable bone marrow suppression. This case report demonstrates the potential for repeated treatments with radioimmunotherapy agents in patients with chemotherapy-refractory non-Hodgkin's lymphoma.