Rare NUP98::SETBP1 fusion transcript in a refractory adult T-cell lymphoblastic lymphoma.

T-lymphoblastic lymphoma (T-LBL) is an aggressive malignancy of T-lymphoid precursors, rarely co-occurring with consequent rearrangement of nucleoporin 98 (NUP98) gene. The NUP98::SETBP1 fusion gene was first reported in a de novo T-cell acute lymphoblastic leukemia (T-ALL) patient. However, it has not yet been reported in patients with T-LBL. We report a case of T-LBL with the NUP98::SETBP1 fusion gene. The NUP98::SETBP1 fusion gene was discovered by RNA sequencing (RNA-seq) in the patient's bone marrow cells and verified in various tissues through direct sequencing and reverse transcriptase polymerase chain reaction (RT-PCR). Unfortunately, despite the use of various treatment methods, including traditional chemotherapy, anti-CD7 CAR-T cell therapy, and CD38-targeted therapy, the patient showed no improvement and ultimately died from disease progression. To our knowledge, this is the first report of the translocation involving NUP98 and SETBP1 genes in T-LBL. It is necessary to collect additional cases and conduct carefully designed experiments to establish the recurrence of this fusion in other T-LBL cohorts and confirm its role as a novel oncogenic rearrangement in T-LBL, providing a basis for managing such patients.