Unclassified low grade spindle cell sarcoma with storiform pattern characterized by recurrent novel EWSR1/FUS-NACC1 fusions.

ABSTRACT: Despite extraordinary advances in the molecular characterization of soft tissue tumors as a result of the widespread application of next generation sequencing in clinical practice, a subset of lesions remain difficult to diagnose. In this study we describe 3 unclassified spindle cell sarcomas with a monomorphic cytomorphology and distinctive storiform growth, characterized by novel fusions between EWSR1 or FUS1, and NACC1 genes. The tumors occurred in 3 young adult females (age range: 29-31) involving deep soft tissues, two located in the lower extremity and one in the abdominal wall. All three tumors showed patchy positivity for S100 protein, while being negative for SOX10 and retained H3K27me3 expression. All cases were negative for epithelial or muscle markers. As the findings were non-

SUBMITTER: Antonescu CR 

PROVIDER: S-EPMC8298288 | biostudies-literature | 2021 Aug

REPOSITORIES: biostudies-literature