This provisional entity is a benign fibroblastic neoplasm, with recent reports describing a wide age range, female predilection, and distribution largely in the hands and feet, in superficial (dermal or subcutaneous) locations.

这个暂定实体是一种良性纤维母细胞肿瘤，最近报告描述的年龄范围广，女性多见，主要分布在手和足的浅表（真皮或皮下）部位。

Histologic features include nodular growth, a pattern of zonation demonstrating peripheral areas of intersecting cellular fascicles comprised of bland spindle cells (Fig. 4), and sometimes central areas of hyalinization and infarction.

组织学特征包括结节状生长，显示由温和的梭形细胞组成的交叉细胞束的周围区域呈带状分布（图4），有时中心区域出现玻璃样变和梗死。

IHC reveals diffuse ERG expression, whereas SMA and CD34 are typically negative. This tumor type is defined by fusion of exon 7 of EWSR1 with exon 5 of SMAD3; SMAD3 is an important signal transducer in the TGF-β/SMAD pathway, involved in extracellular matrix synthesis by fibroblasts. This benign neoplasm may recur locally following incomplete excision.

IHC显示弥漫性ERG表达，而SMA和CD34通常为阴性。这种肿瘤类型由EWSR1的第7外显子和SMAD3的第5外显子融合而成；SMAD3是TGF-β/SMAD通路中的一个重要信号转导子，参与成纤维细胞合成细胞外基质。这种良性肿瘤在不完全切除后可能局部复发。