First Case of TAP1 Deficiency with EBV B-Cell Lymphoma Treated with Cellular Immunotherapy

PURPOSE: Mutations in TAP1 represent one cause of Bare Lymphocyte Syndrome (BLS) type I, characterized by impaired human leukocyte antigen (HLA) class I expression and increased susceptibility to infections. EBV-driven lymphomas are rarely reported in BLS patients. Here, we describe the clinical management of a patient with TAP1 deficiency and discuss the treatment of an Epstein-Barr virus (EBV)-associated B cell lymphoma using cellular therapy. METHODS: We report the first case of a TAP1-deficient patient who developed EBV-associated diffuse large B-cell lymphoma (DLBCL). Clinical, immunological, histopathological and genetic evaluations were conducted. Treatment included standard chemotherapy regimens and adoptive immunotherapy with EBV-specific allogeneic T-cells (Tabelecleucel). RESULTS: A male patient presented with childhood-onset chronic respiratory infections and treatment-refractory cutaneous granulomas. Genetic testing revealed a homozygous pathogenic nonsense mutation in TAP1. The patient developed EBV+ DLBCL, refractory to rituximab-based therapies. Partial clinical stabilization was achieved with Tabelecleucel, but disease progression ensued. CONCLUSIONS: This is the first reported TAP1-deficient case developing EBV+ lymphoma, highlighting the malignancy risk in BLS. Adoptive T-cell therapy showed transient benefit, suggesting a promising, though limited, approach in refractory EBV-associated malignancies in immunodeficient patients.