TLE1 Expression in Different Sarcoma Types and its Relation to Clinicopathological Parameters

Background and objectives: Split genes that contain Transducin-Like Enhancer encode transcriptional corepressors that are essential for hematopoiesis and embryogenesis in humans. Synovial sarcomas express Transducin-Like Enhancer-1, a distinct factor which hardly has been shown in other soft tissues malignancies. Transducin-Like Enhancer-1 expression was recently found to be sensitive but not entirely specific for synovial sarcoma. Methods: This retrospective study included eighty paraffin embedded formalin-fixed blocks of different sarcomas which were gathered and picked out of the files of Rizgary teaching hospital lab and from certain private labs in Hawler, during June 2015-December 2022. In this study, Transducin-Like Enhancer-1, a mouse monoclonal antibody was applied on sarcoma cases and its expression was assessed. Results: around one third (30%) of the patients had synovial sarcoma, (16.3%) had undifferentiated pleomorphic sarcoma, and the rest had other types. More than half (55%) of the sarcomas were of high grade, and the Transducin-Like Enhancer-1 score was strongly reactive in 33.8% of the patients. It was also strong in all (100%) the patients with synovial sarcoma, compared with 23.1% of patients with undifferentiated pleomorphic sarcoma, and 0% of the other types of sarcoma (p < 0.001). Conclusion: this study demonstrates that, when synovial sarcoma was kept in the differential diagnosis of spindle cell soft tissue sarcomas, Transducin-Like Enhancer-1 was a highly sensitive and relatively a specific marker.