title: Superficial EWSR1-negative undifferentiated small round cell sarcoma with CIC/DUX4 gene fusion: a new variant of Ewing-like tumors with locoregional lymph node metastasis.
abstract: The present study describes a new case of EWSR1-negative undifferentiated sarcoma with CIC/DUX4 gene fusion. This case is similar to tumors described as primitive undifferentiated round cell sarcomas that occur mainly in the trunk and display an aggressive behavior. To our knowledge, this is the first report of such a tumor presenting locoregional lymph node metastasis. In view of previous studies that prove the existence of a particular variant of undifferentiated sarcoma with Ewing-like morphology and CIC/DUX-4 gene fusion, a search for this gene fusion in all undifferentiated round cell sarcomas should be considered if a conclusive diagnosis cannot be reached following other conventional studies. Although additional cases with more extensive follow-up studies are needed, we believe that EWSR1-negative undifferentiated small round cell sarcoma with CIC/DUX4 gene fusion should be added to the list of new sarcoma variants with the possibility of lymph node metastasis.
authors.affiliation: Pathology Department, Instituto Valenciano de Oncología, Valencia, Spain, isidro.machado@uv.es.
authors.forename: Isidro
authors.initials: I
authors.lastname: Machado
authors.forename: Julia
authors.initials: J
authors.lastname: Cruz
authors.forename: Javier
authors.initials: J
authors.lastname: Lavernia
authors.forename: Luis
authors.initials: L
authors.lastname: Rubio
authors.forename: Jorge
authors.initials: J
authors.lastname: Campos
authors.forename: María
authors.initials: M
authors.lastname: Barrios
authors.forename: Camille
authors.initials: C
authors.lastname: Grison
authors.forename: Virginie
authors.initials: V
authors.lastname: Chene
authors.forename: Gaelle
authors.initials: G
authors.lastname: Pierron
authors.forename: Olivier
authors.initials: O
authors.lastname: Delattre
authors.forename: Antonio
authors.initials: A
authors.lastname: Llombart-Bosch
mesh_terms: D002148:Calmodulin-Binding Proteins / Q000235:genetics*; D018398:Homeodomain Proteins / Q000235:genetics*; D006801:Humans; D007150:Immunohistochemistry; D017404:In Situ Hybridization, Fluorescence; D008207:Lymphatic Metastasis / Q000235:genetics / Q000473:pathology; D008297:Male; D015514:Oncogene Proteins, Fusion / Q000235:genetics; D034802:RNA-Binding Protein EWS; D016601:RNA-Binding Proteins / Q000235:genetics*; D012097:Repressor Proteins / Q000235:genetics*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D018228:Sarcoma, Small Cell / Q000235:genetics* / Q000473:pathology*; D055815:Young Adult
chemical_list: C498610:CIC protein, human; D002148:Calmodulin-Binding Proteins; C121257:DUX4L1 protein, human; C500986:EWSR1 protein, human; D018398:Homeodomain Proteins; D015514:Oncogene Proteins, Fusion; D034802:RNA-Binding Protein EWS; D016601:RNA-Binding Proteins; D012097:Repressor Proteins