title: Response to initial treatment of multisystem Langerhans cell histiocytosis: an important prognostic indicator.
abstract: BACKGROUND
  Reliable prediction of prognosis allowing risk-adapted therapy remains a major issue in the management of multisystem Langerhans cell histiocytosis (LCH). In a recent publication of the International LCH Study Group, response to initial therapy appears to be a reliable outcome predictor. The aim of this study is to test this observation in a cohort of patients treated with more intensive initial therapy. Furthermore, we compare the predictive value of response to initial therapy to some other well-established stratification systems.
  
  
  METHODS
  Response to initial combination chemotherapy (prednisolone, vinblastine, and etoposide) at 6 weeks and its prognostic value was evaluated retrospectively in 63 patients with multisystem LCH from the DAL-HX 83 and 90 Studies, and correlated to some established scoring systems from the literature.
  
  
  RESULTS
  After 6 weeks of therapy, 50/63 (79%) patients qualified as responders, 4/63 (7%) patients showed intermediate response, and 9/63 (14%) patients did not respond. Probability of survival at 5 years was 0.94 +/- 0.03 for responders, 0.75 +/- 0.22 for patients with intermediate response, and only 0.11 +/- 0.10 for non-responders.
  
  
  CONCLUSIONS
  Response to initial therapy appears to be a reliable prognostic predictor. Compared to the published international LCH-I Study, our results suggest that more intensive initial treatment allows a better discrimination between responders and non-responders. This allows to identify a subgroup of patients with extremely poor prognosis (mortality rate 90%) relatively early in the disease course.
authors.affiliation: St. Anna Children's Hospital, Kinderspitalgasse 9, A-1090 Vienna, Austria.
authors.forename: Milen
authors.initials: M
authors.lastname: Minkov
authors.forename: Nicole
authors.initials: N
authors.lastname: Grois
authors.forename: Andreas
authors.initials: A
authors.lastname: Heitger
authors.forename: Ulrike
authors.initials: U
authors.lastname: Pötschger
authors.forename: T
authors.initials: T
authors.lastname: Westermeier
authors.forename: Helmut
authors.initials: H
authors.lastname: Gadner
mesh_terms: D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D004359:Drug Therapy, Combination; D005047:Etoposide / Q000008:administration & dosage; D005260:Female; D006646:Histiocytosis, Langerhans-Cell / Q000145:classification / Q000188:drug therapy* / Q000401:mortality; D006801:Humans; D007223:Infant; D008297:Male; D011239:Prednisolone / Q000008:administration & dosage; D011379:Prognosis; D012189:Retrospective Studies; D015996:Survival Rate; D014747:Vinblastine / Q000008:administration & dosage
chemical_list: D014747:Vinblastine; D005047:Etoposide; D011239:Prednisolone