title: Desmoid-type fibromatosis of the head and neck region in the paediatric population: a clinicopathological and genetic study of seven cases.
abstract: OBJECTIVE
  Desmoid-type fibromatosis (desmoid) is a locally aggressive (myo)fibroblastic lesion. It represents one of the more common fibrous tumours in children and adolescents. The head and neck region is more often involved than in adults.
  
  
  RESULTS
  We investigated the clinicopathological and genetic characteristics of seven paediatric desmoids at this anatomical site, including two cases of desmoplastic fibroma located in the mandible. There were two females and five males with an age range of 1.5-8 years. The sites of the soft tissue lesions were sinonasal (n = 4) and paramandibular (n = 1). All cases showed typical morphology and nuclear β-catenin expression. CTNNB1 gene sequencing, performed successfully in five cases, revealed mutations in three cases with one p.T41A (bone lesion), one p.S37A and one novel mutation, p.D32V (sinonasal soft tissue lesions). Six patients were treated by excision with positive margins in five cases. Follow-up, available for six patients (median 4 years), showed no evidence of disease in four cases, slow progression in one case, and recurrence with stable disease in the last case.
  
  
  CONCLUSIONS
  Our study provides evidence of genetic similarities in desmoid and desmoplastic fibroma. Additionally, we expanded the spectrum of mutations in CTNNB1 with one novel desmoid mutation.
authors.affiliation: Department of Pathology, Radboud University Nijmegen Medical Center, Nijmegen, The Netherlands.
authors.forename: Uta
authors.initials: U
authors.lastname: Flucke
authors.forename: Bastiaan B J
authors.initials: BB
authors.lastname: Tops
authors.forename: Paul J
authors.initials: PJ
authors.lastname: van Diest
authors.forename: Pieter J
authors.initials: PJ
authors.lastname: Slootweg
mesh_terms: D002648:Child; D002675:Child, Preschool; D005260:Female; D018220:Fibroma, Desmoplastic / Q000235:genetics / Q000473:pathology*; D018222:Desmoid Tumors / Q000235:genetics / Q000473:pathology*; D006801:Humans; D007223:Infant; D008297:Male; D008339:Mandibular Neoplasms / Q000235:genetics / Q000473:pathology*; D009154:Mutation; D009669:Nose Neoplasms / Q000235:genetics / Q000473:pathology*; D010256:Paranasal Sinuses / Q000473:pathology*; D051176:beta Catenin / Q000235:genetics
chemical_list: C495270:CTNNB1 protein, human; D051176:beta Catenin
keywords: bone tumours; children; desmoid; desmoplastic fibroma; fibromatosis; head and neck; soft tissue tumours