Haematopoietic stem cell transplantation for refractory Langerhans cell histiocytosis: outcome by intensity of conditioning

Br J Haematol. 2015 Jun;169(5):711-8. doi: 10.1111/bjh.13347. Epub 2015 Mar 27.


Patients with Langerhans cell histiocytosis (LCH) refractory to conventional chemotherapy have a poor outcome. There are currently two promising treatment strategies for high-risk patients: the first involves the combination of 2-chlorodeoxyadenosine and cytarabine; the other approach is allogeneic haematopoietic stem cell transplantation (HSCT). Here we evaluated 87 patients with high-risk LCH who were transplanted between 1990 and 2013. Prior to the year 2000, most patients underwent HSCT following myeloablative conditioning (MAC): only 5 of 20 patients (25%) survived with a high rate (55%) of transplant-related mortality (TRM). After the year 2000 an increasing number of patients underwent HSCT with reduced intensity conditioning (RIC): 49/67 (73%) patients survived, however, the improved survival was not overtly achieved by the introduction of RIC regimens with similar 3-year probability of survival after MAC (77%) and RIC transplantation (71%). There was no significant difference in TRM by conditioning regimen intensity but relapse rates were higher after RIC compared to MAC regimens (28% vs. 8%, P = 0·02), although most patients relapsing after RIC transplantation could be salvaged with further chemotherapy. HSCT may be a curative approach in 3 out of 4 patients with high risk LCH refractory to chemotherapy: the optimal choice of HSCT conditioning remains uncertain.

Keywords: Langerhans cell histiocytosis; allogeneic transplantation; conditioning regimen intensity; survival; treatment failure.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Adolescent
  • Adult
  • Child
  • Child, Preschool
  • Female
  • Graft vs Host Disease / etiology
  • Graft vs Host Disease / prevention & control
  • Hematopoietic Stem Cell Transplantation* / adverse effects
  • Histiocytosis, Langerhans-Cell / mortality
  • Histiocytosis, Langerhans-Cell / pathology
  • Histiocytosis, Langerhans-Cell / therapy*
  • Humans
  • Infant
  • Male
  • Retrospective Studies
  • Transplantation Conditioning*
  • Transplantation, Homologous
  • Treatment Outcome
  • Young Adult