Successful Treatment of Refractory Orbital Plasmacytoma with Chimeric Antigen Receptor T Cell Therapy: A Case Report and Review of the Literature

Abstract

Orbital plasmacytoma is a rare plasma cell tumor that may arise as an aggressive form of extramedullary multiple myeloma. Treatment modalities include surgical excision, radiation, and chemotherapy. Chimeric antigen receptor T cell therapy is currently reserved for refractory disease. The authors present a case of a 69-year-old woman with an extensive orbital plasmacytoma refractory to multimodal therapy who was treated with idecabtagene vicleucel chimeric antigen receptor T cell therapy. Four days after infusion, the patient exhibited grade 1 cytokine release syndrome, which resolved with tocilizumab. The orbital plasmacytoma significantly decreased in size 1 month after treatment and demonstrated complete serological response and sustained tumor burden reduction at 10-month follow-up. This case highlights the efficacy of chimeric antigen receptor T cell therapy for refractory orbital plasmacytoma and calls attention to potential inflammatory toxicities.

Multifocal Extramedullary Plasmacytoma of the Thyroid With Cervical and Paratracheal Lymph Node Involvement and Progression to Multiple Myeloma

“…The strong expression of MUM1 in this patient points to the potential for future studies to identify a possible therapy targeted at this MUM1/MIG relationship to prevent progression from multiple plasmacytomas to multiple myeloma. New treatment modalities involving chimeric antigen receptor T-cell therapy (CAR-T) are also currently being studied and have been shown to reduce tumor burden in one patient with a refractory orbital plasmacytoma [11].…”