Novel EWSR1-SMAD3 Gene Fusions in a Group of Acral Fibroblastic Spindle Cell Neoplasms

摘要: Benign/low-grade fibroblastic tumors encompass a broad spectrum of with different morphologies and molecular genetic abnormalities. However, despite significant progress in recent genomic characterization, there are still this histologic that difficult to classify, lacking known characteristics. Triggered by challenging congenital spindle cell neoplasm arising the heel 1-year-old boy, we applied RNA sequencing for discovery identified novel EWSR1-SMAD3 gene fusion. On basis index case superficial acral location appearance nonspecific immunophenotype, searched our files similar cases screened them fluorescence situ hybridization these Thus an identical fusion was 2 additional clinicopathologic features. Both occurred feet adult women (58 61 y old) were characterized distinctive nodular growth zonation pattern peripheral hypercellular areas arranged short fascicles, transitioning hypocellular central hyalinization infarction. Focal stippled calcification collagenous area present 1 case. All 3 had immunoprofiles, being negative SMA, CD34, CD31, S100, but showing consistent ERG positivity uncertain significance. Follow-up information available patients who developed local recurrences after incomplete initial excisions, at 5 14 months, respectively. None metastatic disease. In summary, report group locally recurrent tumors, bland fascicular growth, occasional pattern, positivity, fusions.