title: Maxillary pseudotumor as initial manifestation of von Willebrand disease, type 2: report of a rare case and literature review.
abstract: OBJECTIVE
  Von Willebrand disease (VWD) is a bleeding disorder associated with inherited defects of von Willebrand factor (VWF). Type 2 N VWD is characterized by impaired FVIII-binding capacity (VWF:FVIIIB). Pseudotumor (PT) represents a serious complication of hemophilia. Case reports of oral PTs in VWD remain scarce.
  
  
  METHODS
  An 11-year-old Caucasian female presented with an expansile gingival mass of the posterior maxilla. Surgical excision of the tumor was performed.
  
  
  RESULTS
  Histopathologically, the tumor was characterized by cystic spaces filled with hemorrhagic material and dense fibrous connective tissue. Postoperatively, the patient suffered prolonged hemorrhage. Results of blood tests showed decreased levels of FVIII function (
  C) and VWF:FVIIIB. Subsequent gene analysis for type 2 N VWD confirmed heterozygosity for the missense mutation p.Arg816 Trp. A diagnosis of oral PT was rendered.
  
  
  CONCLUSIONS
  Here, we report the clinical, radiographic, and microscopic features of a rare example of oral PT leading to the diagnosis of type 2 N VWD.
authors.affiliation: Division of Oral and Maxillofacial Pathology, School of Dentistry, University of Minnesota, Minneapolis, Minnesota, USA.
authors.forename: Prokopios P
authors.initials: PP
authors.lastname: Argyris
authors.affiliation: Department of Pediatrics, University of North Dakota School of Medicine and Health Sciences, Fargo, North Dakota, USA.
authors.forename: Samuel O
authors.initials: SO
authors.lastname: Anim
authors.affiliation: Division of Oral and Maxillofacial Pathology, School of Dentistry, University of Minnesota, Minneapolis, Minnesota, USA. Electronic address: Koutl001@umn.edu.
authors.forename: Ioannis G
authors.initials: IG
authors.lastname: Koutlas
mesh_terms: D002648:Child; D003937:Diagnosis, Differential; D005260:Female; D005887:Gingival Neoplasms / Q000175:diagnosis* / Q000601:surgery*; D006104:Granuloma, Plasma Cell / Q000175:diagnosis* / Q000601:surgery*; D006801:Humans; D008441:Maxillary Neoplasms / Q000175:diagnosis* / Q000601:surgery*; D014842:von Willebrand Diseases / Q000150:complications* / Q000175:diagnosis*