title: Langerhans Cell Histiocytosis of the Orbit: Spectrum of Disease and Risk of Central Nervous System Sequelae in Unifocal Cases.
abstract: OBJECTIVE
  To describe the spectrum of disease extent and clinical response in Langerhans cell histiocytosis (LCH) presenting with orbital involvement and to determine if unifocal orbital disease increases the risk for central nervous system sequelae (CNS-LCH).
  
  
  METHODS
  Retrospective chart review of patients with orbital LCH representing a range of severity treated at the Children's Hospital of Wisconsin from 2003 to 2011; analysis of current international treatment protocols; literature review.
  
  
  RESULTS
  Six patients presenting with orbital LCH are described: 1 with unifocal orbital disease completely responsive to local measures; 1 with multifocal bone disease completely responsive to local intervention; 1 with unifocal orbital disease incompletely responsive to surgical intervention, and requiring systemic chemotherapy; and 3 with multisystem disease at presentation. Literature review identified 806 cases of CNS-LCH. Orbital involvement could be determined in 11 cases. Of these, 6 had multisystem disease and 3 had multifocal bone disease; 1 presented with unifocal orbital disease but progressed to multifocal bone involvement; 1 had insufficient clinical information to distinguish unifocal from multisite presentation. No cases of CNS-LCH directly resulted from isolated unifocal orbital disease.
  
  
  CONCLUSIONS
  Initial treatment of orbital LCH should depend on disease extent at diagnosis. Unifocal cases that completely respond to biopsy, curettage, and/or corticosteroid instillation may be managed with initial oncologic staging and careful long-term observation, with default to chemotherapy for local recurrence or multisite progression. There is currently little evidence that unifocal orbital disease increases the risk for CNS-LCH and therefore warrants prophylactic systemic chemotherapy in all patients.
authors.affiliation: Section of Orbital and Ophthalmic Plastic Surgery, Department of Ophthalmology, Medical College of Wisconsin, Milwaukee, Wisconsin, U.S.A.
authors.forename: Neda
authors.initials: N
authors.lastname: Esmaili
authors.forename: Gerald J
authors.initials: GJ
authors.lastname: Harris
mesh_terms: D018949:Antigens, CD1 / Q000378:metabolism; D015415:Biomarkers / Q000378:metabolism; D002493:Central Nervous System Diseases / Q000175:diagnosis*; D002648:Child; D002675:Child, Preschool; D017338:Cladribine / Q000627:therapeutic use; D003475:Curettage; D005260:Female; D006646:Histiocytosis, Langerhans-Cell / Q000000981:diagnostic imaging* / Q000188:drug therapy / Q000378:metabolism; D006801:Humans; D007166:Immunosuppressive Agents / Q000627:therapeutic use; D007223:Infant; D008297:Male; D008775:Methylprednisolone / Q000627:therapeutic use; D009915:Orbit / Q000000981:diagnostic imaging; D009916:Orbital Diseases / Q000000981:diagnostic imaging* / Q000188:drug therapy / Q000378:metabolism; D012189:Retrospective Studies; D012307:Risk Factors; D014057:Tomography, X-Ray Computed; D014222:Triamcinolone Acetonide / Q000627:therapeutic use
chemical_list: D018949:Antigens, CD1; D015415:Biomarkers; D007166:Immunosuppressive Agents; D017338:Cladribine; D014222:Triamcinolone Acetonide; D008775:Methylprednisolone