Effect of different conditioning regimens on survival and engraftment for children with hemophagocytic lymphohistiocytosis undergoing allogeneic hematopoeitic stem cell transplantation: A single institution experience.

Hemophagocytic lymphohistiocytosis (HLH), a rare hyperinflammatory immuneregulatory disorder, is a challenge in hematopoietic stem cell transplantation (HSCT) because of the high rate of mixed chimerism, relapse, and graft failure (GF) unless intensive myeloablative regimens are used. However, historically conventional myeloablative regimens (conv MA) are associated with high toxicity and mortality. We retrospectively compared transplant outcomes between three preparative regimens of varying intensities: Conv MA (n = 15), reduced-intensity conditioning (RIC, n = 12), and a treosulfan-based reduced-toxicity conditioning (RTC, n = 9). Patients in the RIC cohort had a higher incidence of mixed donor chimerism and five patients (42%) developed secondary GF (P = .002) compared to the other two regimens. There was a higher incidence of veno-occlusive disease and intensive care unit (ICU) admissions in the Conv MA cohort. With the RTC regimen, there was a similar 2-year overall survival (89, 73, and 83%; P = .87), but improved compound EFS (lack of relapse, GF, second transplant or additional donor cell infusions, or death; 89, 73, and 42%, P = .041) in RTC, Conv MA, and RIC regimen, respectively. The intensity of the preparative regimen has a significant impact on outcome of HSCT for HLH. The newly described treosulfan-based RTC provides for a stable graft with a reasonable toxicity profile.

Ali S ，Wall DA ，Ali M ，Chiang KY ，Naqvi A ，Weitzman S ，Gassas A ，Gibson P ，Brager R ，Fernandez CV ，Crooks B ，Schechter T ，Krueger J ... -  《-》

[The clinical characteristics of adult hemophagocytic lymphohistiocytosis treated with haploidentical donor hematopoietic stem cell transplantation].

Fu L ，Wei N ，Wang JS ，Wu L ，Wang YN ，Huang DY ，Liu JL ，Wang Z ... -  《-》

Treosulfan-based conditioning regimen for children and adolescents with hemophagocytic lymphohistiocytosis.

Lehmberg K ，Albert MH ，Beier R ，Beutel K ，Gruhn B ，Kröger N ，Meisel R ，Schulz A ，Stachel D ，Woessmann W ，Janka G ，Müller I ... -  《-》

Outcomes of Children with Hemophagocytic Lymphohistiocytosis Given Allogeneic Hematopoietic Stem Cell Transplantation in Italy.

We report on 109 patients with hemophagocytic lymphohistiocytosis (HLH) undergoing 126 procedures of allogeneic hematopoietic stem cell transplantation (HSCT) between 2000 and 2014 in centers associated with the Italian Pediatric Hematology Oncology Association. Genetic diagnosis was FHL2 (32%), FHL3 (33%), or other defined disorders known to cause HLH (15%); in the remaining patients no genetic abnormality was found. Donor for first transplant was an HLA-matched sibling for 25 patients (23%), an unrelated donor for 73 (67%), and an HLA-partially matched family donor for 11 children (10%). Conditioning regimen was busulfan-based for 61 patients (56%), treosulfan-based for 21 (20%), and fludarabine-based for 26 children (24%). The 5-year probabilities of overall survival (OS) and event-free survival (EFS) were 71% and 60%, respectively. Twenty-six patients (24%) died due to transplant-related causes, whereas 14 (13%) and 10 (9%) patients experienced graft rejection and/or relapse, respectively. Twelve of 14 children given a second HSCT after graft failure/relapse are alive and disease-free. Use of HLA-partially matched family donors was associated with higher risk of graft failure and thus with lower EFS (but not with lower OS) in multivariable analysis. Active disease at transplantation did not significantly affect prognosis. These data confirm that HSCT can cure most HLH patients, active disease not precluding successful transplantation. Because in HLH patients HLA-haploidentical HSCT performed through CD34+ cell positive selection was found to be associated with poor sustained engraftment of donor cells, innovative approaches able to guarantee a more robust engraftment are warranted in patients given this type of allograft.

Messina C ，Zecca M ，Fagioli F ，Rovelli A ，Giardino S ，Merli P ，Porta F ，Aricò M ，Sieni E ，Basso G ，Ripaldi M ，Favre C ，Pillon M ，Marzollo A ，Rabusin M ，Cesaro S ，Algeri M ，Caniglia M ，Di Bartolomeo P ，Ziino O ，Saglio F ，Prete A ，Locatelli F ... -  《-》

Incidence and Outcomes of Central Nervous System Hemophagocytic Lymphohistiocytosis Relapse after Reduced-Intensity Conditioning Hematopoietic Stem Cell Transplantation.

Hemophagocytic lymphohistiocytosis (HLH) is an immune regulatory disorder that commonly presents with central nervous system (CNS) involvement. The only cure for genetic HLH is hematopoietic stem cell transplantation (HSCT), typically treated with reduced-intensity conditioning (RIC) regimens. We sought to estimate the incidence of CNS relapse after RIC HSCT, determine risk factors, and evaluate outcomes. We performed a retrospective chart review of 94 consecutive children and young adults with primary HLH who received RIC HSCT. CNS relapse within 1 year after transplantation was diagnosed by review of clinical symptoms, cerebral spinal fluid (CSF), and radiologic findings. Four (4.25%) patients developed symptoms of possible CNS HLH after HSCT and 3 patients were diagnosed. Eight patients underwent screening lumbar puncture because of history of active CNS disease at the onset of the conditioning regimen and 4 had evidence of continued disease. The overall incidence of CNS relapse and continued CNS disease after RIC HSCT was 8%. All patients with CNS disease after HSCT responded to CNS-directed therapy. Whole blood donor chimerism at the time of CNS relapse was low at 1% to 34%, but it remained high at 88% to 100% for patients with continued CNS disease. Overall survival for patients with CNS relapse was 50%, compared with 75% for patients without CNS disease (P = .079). Our data suggest that a low level of donor chimerism or active CNS disease at the time of transplantation increase the risk of CNS HLH after HSCT. Surveillance CSF evaluation after allogeneic RIC HSCT should be considered in patients with risk factors and CNS-directed treatment should be initiated if appropriate.

Lounder DT ，Khandelwal P ，Chandra S ，Jordan MB ，Kumar AR ，Grimley MS ，Davies SM ，Bleesing JJ ，Marsh RA ... -  《-》