title: The use of reduced-intensity stem cell transplantation in haemophagocytic lymphohistiocytosis and Langerhans cell histiocytosis.
abstract: Allogeneic stem cell transplant is curative for haemophagocytic lymphohistiocytosis (HLH) and refractory Langerhans cell histiocytosis (LCH). However, patients frequently have significant pre-transplant morbidity and there is high TRM. Because HLH is caused by immune dysregulation, we surmised that a reduced-intensity conditioned (RIC) regimen might be sufficient for cure, while decreasing the TRM. In 2006, we reported the outcome of 12 patients treated with RIC SCT from a matched family/unrelated or haploidentical donor. Here we discuss the update of these patients, including a total of 25 patients treated with RIC SCT for HLH and three for LCH. Twenty-one of the twenty-five patients with HLH (84%) are alive and well with remission at a median of 36 months from SCT. Mortality included pneumonitis (n=3) and hepatic rupture (n=1). All three patients treated with RIC SCT for LCH remain alive and in remission at a median of 5.1 years from SCT. Seven of twenty-four survivors (one with LCH) have mixed chimerism but remain disease-free. These data are supported by other groups including 100% survival in seven patients with HLH and 78% survival of nine patients with LCH. In summary, RIC compares favourably with conventional SCT with long-term disease control in surviving patients with both HLH and LCL, despite a significant incidence of mixed chimerism.
authors.affiliation: Department of Bone Marrow Transplantation, Great Ormond Street Hospital for Children NHS Trust, London, UK.
authors.forename: N
authors.initials: N
authors.lastname: Cooper
authors.forename: K
authors.initials: K
authors.lastname: Rao
authors.forename: N
authors.initials: N
authors.lastname: Goulden
authors.forename: D
authors.initials: D
authors.lastname: Webb
authors.forename: P
authors.initials: P
authors.lastname: Amrolia
authors.forename: P
authors.initials: P
authors.lastname: Veys
mesh_terms: D018572:Disease-Free Survival; D006646:Histiocytosis, Langerhans-Cell / Q000401:mortality / Q000628:therapy*; D006801:Humans; D008107:Liver Diseases / Q000209:etiology / Q000401:mortality; D019520:Living Donors; D051359:Lymphohistiocytosis, Hemophagocytic / Q000401:mortality / Q000628:therapy*; D011014:Pneumonia / Q000209:etiology / Q000401:mortality; D012074:Remission Induction; D012422:Rupture, Spontaneous; D033581:Stem Cell Transplantation; D015996:Survival Rate; D018183:Transplantation Chimera; D014184:Transplantation, Homologous