Background and purpose
Acute leukemias with chimeric fusion genes involving FET (FUS, EWSR1, TAF15) family proteins and ETS (E26 transformation-specific)-like transcription factors often exhibit unique clinical and pathological features. This mini-review focuses on fusion sarcoma (FUS) or Ewing sarcoma breakpoint region 1 (EWSR1)gene.
method
An extensive literature review of reported cases of acute leukemia was conducted. FUS or EWSR1. Introducing details and summary information of reported cases.
result
Rare cases of acute leukemia are found to harbor one of the following: FUS or EWSR1 Genetic rearrangements with ETS or non-ETS proteins as partners exhibit heterogeneous clinical and pathological features. people with acute leukemia FUS Genetic rearrangements are associated with diverse immunophenotypes and occur primarily, but not exclusively, in acute myeloid leukemia (AML), with ERG being the most frequent fusion partner. In contrast, in acute leukemia, EWSR1 Genetic rearrangements occur more commonly as B-cell acute lymphoblastic leukemia (ALL) and mixed-phenotype acute leukemia (MPAL). ZNF384 as a major partner. at present, FUS::ERG-Positive AML Facts::ETS This fusion is officially recognized in the World Health Organization Classification of Hemolymphatic Malignancies, Fifth Edition (WHO-HEM5) and the International Consensus Classification (ICC) system. Cytogenetic karyotype analysis and fluorescence on site Hybridization remains an important tool for detecting chromosomal translocations in more than half of acute leukemia patients. FUS or EWSR1 Gene rearrangement. However, some patients may have a normal karyotype and require advanced molecular diagnostic methods. EWSR1-Rearranged leukemias are difficult to distinguish from Ewing’s sarcoma and require special attention.
conclusion
As more cases and additional data become available, expanding this category of acute leukemia to include other specific acute leukemia entities with fusions such as FET::ETS may be warranted. FUS::FLI1 and FUS::FEV, in addition to FUS::ERG-AML positive. However, additional data are required to support such subclassification. In contrast, for AML, EWSR1 Relocations are very rare and show considerable variability. Cases of B-ALL or B/myeloid MPAL EWSR1::ZNF384 Fusion may be more appropriately classified with others. ZNF384-Reorganized leukemia subtypes. Advanced molecular diagnostic methods, particularly RNA-based next-generation sequencing, have been suggested to improve the accurate diagnosis of acute leukemia. FUS or EWSR1 fusion. Additional pathological workup, especially immunohistochemical staining with hematopoietic markers, is strongly recommended for differentiation. EWSR1– Leukemia reconstructed from Ewing’s sarcoma.
sauce:
Reference magazines:
Ding, Y. & Cheng, J. (2026). Heterogeneous phenotype of acute leukemia EWSR1 or FUS Genetic rearrangement. Journal of Clinical Pathology. DOI: 10.14218/JCTP.2026.00010. https://www.xiahepublishing.com/2771-165X/JCTP-2026-00010
