title: Long-term follow-up of Langerhans cell histiocytosis: 39 years' experience at a single centre.
abstract: OBJECTIVE
  To evaluate the long-term outcome of Langerhans cell histiocytosis (LCH) in children.
  
  
  METHODS
  We re-evaluated all children (<15 y old at diagnosis) treated at our unit in 1962-1989. Histopathology specimens were reviewed and verified for 49 patients. Forty patients underwent physical examination and laboratory tests, and 38 were subjected to imaging, at a median time of 16 y (range 5.5-33.5) after diagnosis.
  
  
  RESULTS
  Altogether, 5/49 (10%) children died, all with multi-system disease and age <2 y at diagnosis. Age at diagnosis (p=0.001) and survival (p=0.014) for the 22 children with multi-system disease was significantly lower compared with the 27 children with single-system disease. The term "maximal extent of disease" was introduced since reactivation of LCH often tends to involve additional organs not previously affected by the disease. At follow-up, late sequelae had developed in 17/40 (42%) patients, including diabetes insipidus in 6/40 (15%), CNS complications in at least 4/40 (10%) (3/16, 19%, of multi-system patients) and late-stage pulmonary disease in 4/38 (11%). Seven out of 21 (33%) of the patients with multi-system disease were alive and healthy without sequelae at follow-up, as compared to 16/24 (67%) of those with single-system disease (p=0.026). Of 14 individuals 25 y at follow-up, senior high school had been completed in 7/9 (78%) with single-system and 1/5 (20%) with multi-system disease (at maximal disease extent) (p=0.091).
  
  
  CONCLUSIONS
  Multi-system LCH is associated not only with increased mortality but also pronounced propensity for severe late sequelae; 51% of the patients (multi-system=33%, single-system=67%) were alive without sequelae at follow-up. Among multi-system patients, at least 19% suffered CNS sequelae.
authors.affiliation: Childhood Cancer Research Unit, Department of Woman and Child Health, Astrid Lindgren Children's Hospital, Karolinska Hospital, Stockholm, Sweden.
authors.forename: Cecilia
authors.initials: C
authors.lastname: Bernstrand
authors.forename: Bengt
authors.initials: B
authors.lastname: Sandstedt
authors.forename: Lars
authors.initials: L
authors.lastname: Ahström
authors.forename: Jan-Inge
authors.initials: JI
authors.lastname: Henter
mesh_terms: D000367:Age Factors; D002423:Cause of Death; D002648:Child; D002675:Child, Preschool; D003131:Combined Modality Therapy; D018450:Disease Progression; D018572:Disease-Free Survival; D005260:Female; D005500:Follow-Up Studies; D006646:Histiocytosis, Langerhans-Cell / Q000175:diagnosis* / Q000401:mortality* / Q000628:therapy; D006801:Humans; D008297:Male; D011336:Probability; D012042:Registries; D012189:Retrospective Studies; D018570:Risk Assessment; D012720:Severity of Illness Index; D012737:Sex Factors; D016019:Survival Analysis; D013548:Sweden / Q000453:epidemiology; D013997:Time Factors