EWSR1-SMAD3 Rearranged Fibroblastic Tumor

**Semantic type:** Neoplastic Process

**Definition:** A benign fibroblastic neoplasm characterized by a fusion of exon 7 of EWSR1 gene with exon 5 of SMAD3 gene. Patients usually present with a small painless superficial tumor in the hands and feet. Morphologically, there is zonation with acellular hyalinized center and peripheral proliferation of fibroblastic spindle cells without atypia. It may recur following incomplete excision.

**Synonyms:** - EWSR1-SMAD3-Positive Fibroblastic Tumor - EWSR1::SMAD3 Rearranged Fibroblastic Tumor - EWSR1::SMAD3-Positive Fibroblastic Tumor