title: Radiotherapy for bony manifestations of Langerhans cell histiocytosis. Review and proposal for an international registry.
abstract: OBJECTIVE
  To examine the role of radiotherapy (RT) in adult Langerhans cell histiocytosis (LCH) for osseous manifestations, to define open questions regarding RT, and to develop recommendations for the clinical decision-making and problem-solving process.
  
  
  METHODS
  A literature review using different medical databases was conducted including the last 3 decades, and resulting questions regarding the use of ionizing radiation were systematically compiled.
  
  
  RESULTS
  The literature review revealed a local control rate of 96% (93% complete remissions) in patients with osseous single-system disease and of 92% (76% complete remissions) in patients with bony involvement in multi-system disease. To increase our knowledge, a prospective registry has been developed to allow a differentiated analysis of RT outcome and definition of potential prognostic factors.
  
  
  CONCLUSIONS
  Ionizing radiation can be successfully applied as a single treatment or in combination with other therapies for osseous manifestations of LCH. It leads to high remission and local control rates. Nevertheless, many open questions still exist. A prospective clinical registry is proposed to define the exact role of RT in this disease and to develop future interdisciplinary treatment guidelines.
authors.affiliation: Department of Radiotherapy and Radiation Oncology, Alfried Krupp Krankenhaus, Alfried-Krupp-Strasse 21, 45117 Essen, Germany. bernd-pothmann@krupp-krankenhaus.de
authors.forename: Thomas
authors.initials: T
authors.lastname: Olschewski
authors.forename: Michael Heinrich
authors.initials: MH
authors.lastname: Seegenschmiedt
mesh_terms: D001847:Bone Diseases / Q000532:radiotherapy*; D006646:Histiocytosis, Langerhans-Cell / Q000532:radiotherapy*; D006801:Humans; D011446:Prospective Studies; D012042:Registries; D016896:Treatment Outcome