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Cutaneous non‐Langerhans cell histiocytosis (NLCH) is a rare and biologically benign entity that can be broadly classified into two categories: xanthogranuloma and non‐xanthogranuloma. The xanthogranuloma family is characterized by a proliferation of histiocytes with both macrophage and dendritic cell differentiation, negative BRAF mutation, and rare Touton‐type giant cells. Molecular studies have reported that mutations involved in the MAPK signaling pathways are implicated in the pathophysiology of histiocytoses. While LCH is associated with the somatic mutation of BRAF v600e, however, mutations and gene fusions in NLCH cases are undefined. We hereby present a 19‐month‐old female with recalcitrant nodular rashes diagnosed as NLCH with associated novel genetic mutation involving ANKRD26 and PDGFRB genes, as well as PDGFRB::CD74 fusion mRNA. Immunohistochemical staining showed strong and diffuse CD68 and CD163 positivity, and negative CD1a, CD207, ALK D5F3, S100 protein, and BRAF V600E (VE1). Albeit unknown significance, this case of an ANKRD26 and PDGFRB gene mutation in cutaneous NLCH has not been reported prior in the literature. Our case highlights the advantage of pathology and genetic studies in cutaneous NLCH to increase the understanding of this heterogeneous enigmatic disorder and identify further options in management. [ABSTRACT FROM AUTHOR]

Verrucous venous malformations (VVM) are rare, congenital, slow‐flow vascular anomalies that have been historically difficult to characterize due to clinical mimics and unclear histological evaluation. A life‐threatening complication of VVMs is localized intravascular coagulation. Herein, we describe a male neonate who presented with a congenital VVM on the left lower extremity with associated severe thrombocytopenia. We discuss the multifaceted diagnostic approach used to identify this VVM, while highlighting the use of WT‐1 as a negative predictive marker; we additionally outline novel treatment options and management beyond cutaneous involvement. [ABSTRACT FROM AUTHOR]