title: Long term follow up of topical mustine treatment for cutaneous langerhans cell histiocytosis.
abstract: OBJECTIVE
  Skin lesions in Langerhans cell histiocytosis (LCH) are often painful and difficult to treat. Topical application of nitrogen mustard (0.02% mechlorethamine hydrochloride, mustine), an alkylating cytostatic agent, has been shown to be effective. There is, however, concern about potentially harmful long term side effects.
  
  
  METHODS
  In a retrospective study 20 children with LCH (average extent of initial skin involvement: 16.4% body surface) were followed up for an average of 8.3 years after completion of topical mustine therapy. They had received a total of 34 courses (mean duration 14.2 weeks) of topical mustine. Disease status on follow up was assessed according to the Histiocyte Society classification.
  
  
  RESULTS
  After mustine was introduced, 16 patients were able to discontinue systemic steroids and/or chemotherapy. Topical mustine was well tolerated in 18 patients, but two developed irritant dermatitis. On follow up, the disease was inactive in 10 patients. Among the children with active disease, six had mild skin disease and four had progressive disease, two of them with skin lesions unresponsive to mustine treatment. Scars confined to areas of formerly active skin disease were found in six patients. There was no evidence of premalignant or malignant skin disease in the treated areas.
  
  
  CONCLUSIONS
  Topical mustine is an effective and safe treatment for skin disease in most children with LCH. Residual scarring was probably a result of the disease itself rather than to mustine. Although no evidence of skin cancer was found in this study, continued long term follow up is advisable.
authors.affiliation: Department of Dermatology and Institute of Child Health, Great Ormond Street Hospital for Children NHS Trust, London, UK. hoeger@uke.uni-hamburg.de
authors.forename: P H
authors.initials: PH
authors.lastname: Hoeger
authors.forename: V R
authors.initials: VR
authors.lastname: Nanduri
authors.forename: J I
authors.initials: JI
authors.lastname: Harper
authors.forename: D A
authors.initials: DA
authors.lastname: Atherton
authors.forename: J
authors.initials: J
authors.lastname: Pritchard
mesh_terms: D000287:Administration, Topical; D000477:Alkylating Agents / Q000008:administration & dosage* / Q000009:adverse effects; D002648:Child; D002675:Child, Preschool; D003879:Dermatologic Agents / Q000008:administration & dosage* / Q000009:adverse effects; D005260:Female; D005500:Follow-Up Studies; D006646:Histiocytosis, Langerhans-Cell / Q000188:drug therapy*; D006801:Humans; D007223:Infant; D008297:Male; D008466:Mechlorethamine / Q000008:administration & dosage* / Q000009:adverse effects; D012189:Retrospective Studies; D012871:Skin Diseases / Q000188:drug therapy*
chemical_list: D000477:Alkylating Agents; D003879:Dermatologic Agents; D008466:Mechlorethamine