Radioimmunotherapy ((90) Y-Ibritumomab Tiuxetan) for Posttransplant Lymphoproliferative Disorders After Prior...

Area of Science:

• Oncology
• Immunology
• Transplantation Medicine

Background:

• Posttransplantation lymphoproliferative disorders (PTLDs) are serious complications following transplantation.
• Rituximab monotherapy is effective in only half of CD20-positive PTLDs, with poor outcomes for relapsed/refractory cases.
• Some patients are ineligible for standard chemotherapy due to frailty or comorbidities.

Purpose of the Study:

• To evaluate the efficacy and safety of radioimmunotherapy (RIT) as a salvage treatment for rituximab-refractory/relapsed CD20-positive PTLDs.
• To assess RIT in patients ineligible for further chemotherapy.

Main Methods:

• Retrospective analysis of eight patients with rituximab-refractory/relapsed CD20-positive PTLDs.
• Treatment involved (90)Y-Ibritumomab tiuxetan (RIT) as a single agent (n=7) or combined with chemotherapy (n=1).
• Patients had undergone various solid organ transplants, including kidney, liver, and heart.

Main Results:

• An overall response rate of 62.5% was observed.
• All responders achieved a complete response (CR).
• At a median follow-up of 37 months, CR was ongoing in four patients; toxicity was primarily hematological and manageable. No graft rejection occurred.

Conclusions:

• Salvage RIT demonstrates potential efficacy for early rituximab-refractory PTLDs.
• RIT offers a viable treatment option for patients ineligible for chemotherapy.
• The treatment was well-tolerated with no unexpected toxicities, including graft rejection.