B/T Mixed Phenotype Acute Leukaemia Harbouring NUP98::BPTF Fusion.

Background: NUP98::BPTF rearranged (r) leukaemia is rare with only five reported cases, including acute myeloid leukemia and T-lymphoblastic leukemia (T-ALL). Results: Herein, we report a case of NUP98::BPTF-r mixed phenotype acute leukemia (MPAL), B/T with T-lineage-predominance in a 15-year-old female. Cytogenetic and molecular studies revealed a t(11;17)(p15;q23)/NUP98::BPTF fusion and cooperative gene alterations characteristic of T-ALL (NOTCH1, FBXW7, and PHF6). Our patient had a primary induction failure with T-ALL-directed chemotherapy and achieved complete remission following consolidation. Conclusion: This is the first case study characterizing the clinicopathological and genomic features of B/T MPAL harboring NUP98::BPTF fusion and providing insights into molecular pathogenesis. Trial Registration: The authors have confirmed clinical trial registration is not needed for this submission.