Peripheral blood stem cell collection in children with extremely low body weight (≤8 kg). What have we learned over the past 25 years and where are the limits?

Hematopoietic progenitor cells-apheresis (HPC-A) collection is now a routine procedure for autologous hematopoietic stem cell transplantation. Here we present our 25 years' experience of HPC-A collection in children weighing 8 kg or less, with a focus on the evolution of our standard operating procedures, and the safety limits for these young patients, in the Pediatric Apheresis Unit of Clermont-Ferrand University Hospital (France). Fifteen children weighing 8 kg or less underwent 26 HPC-A collections over 25 years. Median CD34+ cell yield by leukapheresis was 4.4 106 /kg. No procedure-related complications were encountered during or after the collection. No patient had profound thrombocytopenia or anemia that needed post-collection transfusions. Our experience in pediatric oncology patients who underwent HPC-A collections shows that this procedure can be performed even in the smallest of children with no increase in toxicity provided all precautions are taken to ensure that the procedure is carried out under the ideal conditions.

Functional classification of ATM variants in ataxia-telangiectasia patients.

Ataxia-telangiectasia (A-T) is a recessive disorder caused by biallelic pathogenic variants of ataxia-telangiectasia mutated (ATM). This disease is characterized by progressive ataxia, telangiectasia, immune deficiency, predisposition to malignancies, and radiosensitivity. However, hypomorphic variants may be discovered associated with very atypical phenotypes, raising the importance of evaluating their pathogenic effects. In this study, multiple functional analyses were performed on lymphoblastoid cell lines from 36 patients, comprising 49 ATM variants, 24 being of uncertain significance. Thirteen patients with atypical phenotype and presumably hypomorphic variants were of particular interest to test strength of functional analyses and to highlight discrepancies with typical patients. Western-blot combined with transcript analyses allowed the identification of one missing variant, confirmed suspected splice defects and revealed unsuspected minor transcripts. Subcellular localization analyses confirmed the low level and abnormal cytoplasmic localization of ATM for most A-T cell lines. Interestingly, atypical patients had lower kinase defect and less altered cell-cycle distribution after genotoxic stress than typical patients. In conclusion, this study demonstrated the pathogenic effects of the 49 variants, highlighted the strength of KAP1 phosphorylation test for pathogenicity assessment and allowed the establishment of the Ataxia-TeLangiectasia Atypical Score to predict atypical phenotype. Altogether, we propose strategies for ATM variant detection and classification.

Follow-up of post-transplant minimal residual disease and chimerism in childhood lymphoblastic leukaemia: 90 d to react.

Relapse after transplantation is a major cause of treatment failure in paediatric acute lymphoblastic leukaemia (ALL). Here, we report the findings of a prospective national study designed to investigate the feasibility of immune intervention in children in first or subsequent remission following myeloablative conditioning. This study included 133 children who received a transplant for ALL between 2005 and 2008. Minimal Residual Disease (MRD) based on T cell receptor/immunoglobulin gene rearrangements was measured on days -30, 30, 90 and 150 post-transplantation. Ciclosporin treatment was rapidly discontinued and donor lymphocyte infusions (DLI) were programmed for patients with a pre- or post-transplant MRD status ≥10(-3) . Only nine patients received DLI. Pre- and post-transplant MRD status, and the duration of ciclosporin were independently associated with 5-year overall survival (OS), which was 62·07% for the whole cohort. OS was substantially higher in patients cleared of MRD than in those with persistent MRD (52·3% vs. 14·3%, respectively). Only pre-transplant MRD status (Hazard Ratio 2·57, P = 0·04) and duration of ciclosporin treatment (P < 0·001) were independently associated with relapse. The kinetics of chimerism were not useful for predicting relapse, whereas MRD monitoring up to 90 d post-transplantation was a valuable prognostic tool to guide therapeutic intervention.

Cohort Profile: the French childhood cancer survivor study for leukaemia (LEA Cohort).

The main aim of the Leucémies de l'Enfant et l'Adolescent (LEA) project (Childhood and Adolescent Leukaemia) is to study the determinants (medical, socioeconomic, behavioural and environmental) of medium- and long-term outcomes of patients treated for childhood acute leukaemia (AL). The LEA study began in 2004 and is based on a French multicentric prospective cohort. Included are children treated for AL since January 1980 (incident and prevalent cases), surviving at month 24 for myeloblastic AL and lymphoblastic AL grafted in first complete remission or at month 48 for lymphoblastic AL not grafted in first complete remission. Information is collected during specific medical visits and notably includes the following data: socioeconomic data, AL history, physical late effects (such as fertility, cardiac function and metabolic syndrome) and quality of life. Data are collected every 2 years until the patient is 20 years old and has had a 10-year follow-up duration from diagnosis or last relapse. Thereafter, assessments are planned every 4 years. In active centres in 2013, eligible patients number more than 3000. The cohort has already included 2385 survivors, with rate of exhaustiveness of almost 80%. Data access can be requested from principal coordinators and must be approved by the steering committee.

Leukapheresis in management of hyperleukocytosis in children's leukemias.

We describe 16 leukapheresis (LK) procedures performed in 7 children with different types of leukemia and hyperleukocytosis. We also provide an analysis of previously published experiences of pediatric LK. Median age and body weight of patients were 12.3 years (range, 0.2 to 16.7 y) and 49 kg (range, 5 to 61 kg). Immediate pre-first-LK median white blood cell count was 478×10/L (108×10/L to 988×10/L). All cytoreduction were performed on Cobe Spectra cell separator. Sixty-eight percent of procedures were performed with peripheral veins. Extracorporeal line had been primed with red blood cell for 31% of LK. The median decrease in white blood cell count after each LK was 33% (0% to 69%), and overall decrease after completion of LK procedures was 62% (11% to 94%). Only minor clinical adverse events and no metabolic complication were attributable to LK. No more clinical symptom of hyperleukocytosis was observed after completion of LK procedures. Our findings are consistent with reported results in other pediatric series: LK is a well-tolerated procedure that can be safely performed with an experienced pediatric team even on the smallest children.

Clinical value of pre-transplant minimal residual disease in childhood lymphoblastic leukaemia: the results of the French minimal residual disease-guided protocol.

Minimal residual disease (MRD) is a major predictive factor of the cure rate of acute lymphoblastic leukaemia (ALL). Haematopoietic cell transplantation is a treatment option for patients at high risk of relapse. Between 2005 and 2008, we conducted a prospective study evaluating the feasibility and efficacy of the reduction of immunosuppressive medication shortly after a non-ex vivo T depleted myeloablative transplantation. Immunoglobulin (Ig)H/T-cell receptor MRD 30 d before transplant could be obtained in 122 of the 133 cases of high-risk paediatric ALL enrolled. There were no significant demographic differences except remission status (first or second complete remission) between the 95 children with MRD <10(-3) and the 27 with MRD ≥10(-3) . Multivariate analysis identified sex match and MRD as being significantly associated with 5-year survival. MRD ≥10(-3) compromised the 5-year cumulative incidence of relapse (43·6 vs. 16·7%). Complete remission status and stem cell source did not modify the relationship between MRD and prognosis. Thus, pre-transplant MRD is still a major predictor of outcome for ALL. The MRD-guided strategy resulted in survival for 72·3% of patients with MRD<10(-3) and 40·4% of those with MRD ≥10(-3).

Prevalence and risk factors of cataract after chemotherapy with or without central nervous system irradiation for childhood acute lymphoblastic leukaemia: an LEA study.

Corticosteroid and central nervous system (CNS) irradiation can induce cataract in childhood lymphoblastic leukaemia survivors. Few prospective studies with systematic ophthalmological evaluation have been published. Cataract was prospectively assessed by serial slip lamp tests in 517 patients. All had acute lymphoblastic leukaemia, all had been treated by chemotherapy with or without CNS irradiation, and none had received haematopoietic stem cell transplantation. Median ages at last evaluation and follow-up duration from leukaemia diagnosis were 16·8 and 10·9 years, respectively. Cataract was observed in 21/517 patients (4·1%). Cumulative incidence was 4·5 ± 1·2% at 15 years and reached 26 ± 8·1% at 25 years. CNS irradiation was the only risk factor: prevalence was 11·1% in patients who had received irradiation and 2·8% in those who did not. We did not detect any steroid dose effect: cumulative dose was 5133 and 5190 mg/m(2) in patients with and without cataract, respectively. Cataract occurrence did not significantly impact quality of life. We conclude that, in the range of steroid dose reported here, the cataract risk proves very low 15 years after treatment without CNS irradiation but an even more prolonged follow-up is required because of potential very late occurrence.

Peripheral blood stem cell collection in low-weight children: retrospective comparison of two apheresis devices.

BACKGROUND: Apheresis is a major challenge in peripheral stem cell collection from low-weight children with cancer. Comparisons between the new apheresis device Optia (TerumoBCT) and the earlier COBE Spectra (CaridianBCT) have been performed in adults but not in low-weight children. The objective was to compare the performance of these two devices in small children. STUDY DESIGN AND METHODS: In this retrospective study, all patients were reviewed weighing less than 15 kg undergoing stem cell collection using the Optia device between April 2011 and April 2012. They were paired on weight in a 3:1 ratio with patients whose cells had been collected with the COBE Spectra since 2006. RESULTS: Six patients were treated with the Optia and were matched with 18 patients treated with the Spectra. No side effects occurred. Collection efficiency (CE) was similar between the two groups (50% vs. 47%), but CD34 cell blood clearance was lower with the Optia (0.4 mL/min/kg vs. 0.6 mL/min/kg, p < 0.01). Platelet (PLT) loss and hemoglobin (Hb) loss were significantly reduced with the Optia (respectively, 32% vs. 54%, p < 0.01; and 1.4 g/dL vs. 2.9 g/dL, p < 0.01). Apheresis duration was increased with the Optia (159 min vs. 134 min, p < 0.05). The cell product harvested with the Optia had a lower volume and lower hematocrit, but similar white blood cell and PLT content. CONCLUSION: Compared with the Spectra, the Optia allows similar CE with a reduced PLT and Hb loss but with a longer duration.

Mobilization of hematopoietic stem cells by plerixafor alone in children: a sequential Bayesian trial.

BACKGROUND: The rapid kinetics of hematopoietic stem cells induced by Plerixafor (Mozobil®, Genzyme) should be of particular interest in children. We therefore conducted a prospective trial to determine whether a one-day mobilization by plerixafor alone was efficient enough in children with cancer. METHODS: Children with solid malignancies were consecutively recruited for this phase-IIA, Bayesian single-center prospective study. Mobilization consisted in one subcutaneous injection of 240 µg plerixafor/kg body weight at 8a.m. (h0). Collection by apheresis began at h5 provided that CD34+count exceeded 10 × 10(6)/L. Our main evaluation criterion was percent of children in which at least 5 × 10(6) CD34+/kg could be collected during the first apheresis. RESULTS: No patients fulfilled the success criterion, and so a stopping criterion was met after 5 patients. All patients reached the threshold value of 10 × 10(6) CD34+cells/L post-injection and so all were eligible for apheresis. Peak CD34+cell values were ranged from 11 to 44 × 10(6)/L and were reached in 4h to 6h. No side-effects were observed. Median number of CD34+cells collected per patient BW was 1.62 × 10(6)[0.47-3.5]. In 3 of the 5 patients, collection was>1.5 × 10(6) CD34+/kg BW. CONCLUSION: In children, a 'one-day' mobilization regimen consisting of one injection of 240 µg/kg plerixafor alone in hematological steady state provides a faster and shorter mobilization than in adults. This strategy may be an attractive option for completing an insufficient graft. More studies are warranted to optimize the use of plerixafor in children.

Improvement of the management of infants, children and adults with a molecular diagnosis of Enterovirus meningitis during two observational study periods.

Enteroviruses (EVs) are a major cause of aseptic meningitis, and RNA detection using molecular assay is the gold standard diagnostic test. The aim of this study was to assess the impact of an EV positive diagnosis on the clinical management of patients admitted for meningitis over the course of two observational study periods (2005 and 2008-09) in the same clinical departments. We further investigated in multivariate analysis various factors possibly associated with hospital length of stay (LOS) in all age groups (infants, children, and adults). The results showed an overall improvement in the management of patients (n = 142) between the study periods, resulting in a significantly shorter hospital LOS for adults and children, and a shorter duration of antibiotic use for adults and infants. In multivariate analysis, we observed that the time from molecular test results to discharge of patients and the median duration of antibiotic treatment were associated with an increase in LOS in all age groups. In addition, among adults, the turnaround time of the molecular assay was significantly correlated with LOS. The use of CT scan in children and hospital admission outside the peak of EV prevalence in infants tended to increase LOS. In conclusion, the shorter length of stay of patients with meningitis in this study was due to various factors including the rapidity of the EV molecular test (particularly in adults), greater physician responsiveness after a positive result (in adults and children), and greater experience on the part of physicians in handling EV meningitis, as evidenced by the shorter duration of antibiotic use in adults and infants.

Symptomatic osteonecrosis in childhood leukemia survivors: prevalence, risk factors and impact on quality of life in adulthood.

Corticosteroid can induce osteonecrosis in children with leukemia. Few studies have been designed to assess the influence of a wide range of cumulative steroid dose on this side effect. Prevalence, risk factors of symptomatic osteonecrosis and its impact on adults' Quality of Life were assessed in 943 patients enrolled in the French "Leucémies de l'Enfant et de l'Adolescent" (LEA) cohort of childhood leukemia survivors. During each medical visit, data on previous osteonecrosis diagnosis were retrospectively collected. Patients without a history but with suggestive symptoms were investigated with magnetic resonance imaging. The total steroid dose in equivalent of prednisone was calculated for each patient and its effect on osteonecrosis occurrence was studied in multivariate models. Cumulative incidence was 1.4% after chemotherapy alone versus 6.8% after transplantation (P<0.001). A higher cumulative steroid dose, age over ten years at diagnosis, and treatment with transplantation significantly increased the risk of osteonecrosis. A higher post-transplant steroid dose and age over ten years at time of transplantation were significant factors in the transplanted group. With patients grouped according to steroid dose quartile, cumulative incidence of osteonecrosis reached 3.8% in the chemotherapy group for a dose beyond 5835 mg/m(2) and 23.8% after transplantation for a post-transplant dose higher than 2055 mg/m(2). Mean physical composite score of Quality of Life was 44.3 in patients with osteonecrosis versus 54.8% in patients without (P<0.001). We conclude that total and post-transplant cumulative steroid dose may predict the risk of osteonecrosis, a rare late effect with a strong negative impact on physical domains of Quality of Life.

A French cohort of childhood leukemia survivors: impact of hematopoietic stem cell transplantation on health status and quality of life.

The late effects and quality of life (QoL) in childhood acute leukemia survivors were compared between hematopoietic stem cell transplantation (HSCT) recipients and patients who underwent conventional therapy. The study included 943 patients, 256 of whom underwent HSCT (27.1%). Medical visits were conducted to detect the occurrence of physical late effects. Based on patient age, different questionnaires were used to assess QoL. To evaluate the association between HSCT and each type of late effect or QoL dimension, the appropriate multivariate regressions were performed. QoL mean scores were compared with those obtained for age- and sex-matched French control subjects. Of all the survivors, 674 (71.5%) had at least 1 late effect, with the risk being 5.0 CI95 (3.0-8.6) times higher for transplantation survivors. For child survivors, scoring of QoL showed no significant differences between the treatment groups. The adult HSCT survivors reported lower physical dimension QoL scores than chemotherapy survivors. Compared with French norms, the survivor group reported a significantly lower mental composite score; however, the physical composite score showed no significant difference. Thus, transplanted survivors have a high risk of developing late effects, resulting in a decreased physical well-being in adulthood. However, long after treatment completion, childhood leukemia survivors report that effects on psychological well-being are more important than they are in physical QoL dimensions.

Extracorporeal photochemotherapy: past-it or promising?

Extracorporeal photochemotherapy has been used for almost three decades for the treatment of several T-cell-mediated diseases, and its efficacy has been proven in few well-designed controlled randomized trials. However, to date, there are no reliable data on a hypothetic dose-effect, optimal rhythm of administration, drug interactions, or the "pharmacokinetics" and "pharmacodynamics" of this cell therapy. In particular, it is not clear whether ECP gains to be used in combination with immunosuppressive or immunomodulative drugs. In the future, clinical trials may address these issues in order to clarify the most beneficial use of a cell therapy which absence of toxicity is uniformly recognized.

Excellent prognosis of late relapses of ETV6/RUNX1-positive childhood acute lymphoblastic leukemia: lessons from the FRALLE 93 protocol.

BACKGROUND: The prognosis of patients with relapses of ETV6/RUNX1-positive acute lymphoblastic leukemia remains to be evaluated, particularly with regards to the frequency of late relapses. We performed a long-term, follow-up retrospective study to address the outcome of patients with ETV6/RUNX1-positive leukemia relapses. DESIGN AND METHODS: Among the 713 children tested for ETV6/RUNX1 enrolled into the FRALLE 93 protocol, 43 ETV6/RUNX1-positive patients relapsed (19.4%). Most were initially stratified in the low or intermediate risk groups. The median follow-up after relapse was 54.2 months. All but three received second-line salvage therapy and 16 underwent allogeneic transplantation. RESULTS: ETV6/RUNX1 had a strong effect on overall survival after relapse (3-year survival= 64.7% for positive cases versus 46.5% for negative cases) (P=0.007). The 5-year cumulative incidence of relapse was 19.4% and testes were more frequently involved in ETV6/RUNX1-positive relapses (P=0.04). In 81.4% of cases the relapses were late, early combined or isolated extramedullary relapses. The 5-year survival rate of patients with ETV6-RUNX1-positive acute lymphoblastic leukemia relapses reached 80.8% when the relapse occurred after 36 months (versus 31.2% when the relapse occurred earlier). In univariate analysis, female gender was associated with a poor survival, whereas site of relapse, age at diagnosis, leukocytosis and consolidation strategy had no effect. In multivariate analysis, only the duration of first remission remained associated with outcome. CONCLUSIONS: We found an excellent outcome for patients with ETV6/RUNX1-positive leukemia relapses that occurred more than 36 months after diagnosis. The duration of first complete remission may, therefore, be a guide to define the treatment strategy for patients with relapsed ETV6/RUNX1- positive leukemia.

Weight-based strategy of dose administration in children using intravenous busulfan: clinical and pharmacokinetic results.

BACKGROUND: A prospective clinical trial was performed in order to validate the pharmacokinetic (PK) and clinical benefits of a new dosing schedule of intravenous busulfan (IV Bu) in children. PROCEDURE: IV Bu was administered as a 2-hr infusion every 6 hr for 4 days. Five dose levels were given according to body-weight strata. RESULTS: The 67 children aged from 4 months to 17.2 years were followed up over 50 months after autologous or allogeneic stem-cell transplantation. Reduced PK variability was seen after IV Bu administration enabling efficient targeting with 78% of patients within the 900-1,500 µM · min therapeutic window and reproducible exposures across administrations. No neurological complications occurred. The low incidence of hepatic veno-occlusive disease (VOD) recorded was not correlated with high area under the curve (AUC). Only stomatitis was correlated with high AUC in the autologous group. The 4-year overall survival was 59% in the autologous group and 82% in the allogeneic group. CONCLUSION: The new dosing schedule using IV Bu provides adequate therapeutic targeting from the first administration, with low toxicity and good disease control in high-risk children. The choice of this formulation of Bu should be considered because of its low morbidity and good outcome.

NK cell immunotherapy for high-risk neuroblastoma relapse after haploidentical HSCT.

Little is known on strategies to prevent or to treat relapses occurring after haploidentical stem cell transplantation (haplo-HSCT) performed for the high-risk neuroblastoma (NB). We describe a 6-year-old male with refractory NB who relapsed 22 months after haplo-HSCT. A complete remission was obtained with a combination of immuno-chemotherapy based on donor NK cells transplants, IL2 infusions and temozolomide/topotecan. This case is an incentive to explore both the immediate therapeutic effect of haplo-graft provided via haplo-NK cells and the immunogenic platform that haplo-HSCT offers for future treatment. Our post-relapse strategy shows that chemo- and bio-treatment should be viewed as complementary therapeutic options.

Pathways of care for adolescent patients with cancer in France from 2006 to 2007.

BACKGROUND: In France, as in other countries, there is a need for a population-based view of access to care and modalities of treatment for adolescents with cancer. PROCEDURE: Using a population-based registration, we report pathways of care for 15-19-year-old patients, diagnosed with cancer in 2006 and 2007, living in six French regions, accounting for 41% of the French population. RESULTS: The median times (inter-quartile range) for diagnosis and treatment of the 594 included adolescents were 8 weeks (3-17) and 3 days (0-16), respectively. First physicians met by the patients were mostly general practitioners (59%). Seventeen percent of patients were firstly seen on emergency wards. Most of the patients (82%) were treated in an adult environment. Management decisions were taken within the context of a multi-disciplinary team (MDT) in 54% of cases. Twenty-seven percent of patients were included in randomized or non-randomized clinical studies: percentage depended on the tumor type and on the number of on-going trials at the study period. Fifteen percent of patients were included in pediatric studies, 7% in adult studies, and 5% in studies including both adults and children. CONCLUSIONS: The pathways of care for French adolescent patients with cancer are heterogeneous. Our results reveal differences in MDT meetings according to tumor types and a lack of effective collaboration between pediatric and adult wards. Efforts must be made to develop cancer networks to ensure that adolescents receive the optimal care in a suitable environment.

A dose-intensive approach (NB96) for induction therapy utilizing sequential high-dose chemotherapy and stem cell rescue in high-risk neuroblastoma in children over 1 year of age.

BACKGROUND: To improve outcome and overall survival (OS) in high-risk neuroblastoma, NB96 induction therapy was intensified using sequential high-dose chemotherapy and autologous stem cell rescue. PROCEDURE: Twenty children were included in this pilot study undertaken at seven reference centers in France, between May 1995 and October 1996. Induction began with one cycle of conventional chemotherapy followed by six sequential cycles of high-dose chemotherapy comprising two cycles of etoposide 800 mg/m(2)/day over 3 days, two cycles of cyclophosphamide 2,000 mg/m(2)/day over 3 days, and two cycles of carboplatin 400 mg/m(2)/day over 5 days, followed by stem cell rescue. RESULTS: Thirteen patients (13/20) received this induction with acceptable toxicity and adequate stem cell harvest. Of these, nine (9/13) underwent surgery according to the protocol, while one patient was given a consolidation regimen prior to surgery. No toxic death was recorded. At the end of induction, complete remission was achieved in 10 cases (50%), with six still alive in July 2009. The 5-year event-free survival and OS were 35 ± 11% and 40 ± 11%, respectively. CONCLUSION: NB96 therapy is feasible and tolerated without lethal toxicity. Nevertheless, given the small sample size and absence of randomization in our study, the effectiveness of this strategy based on metastasis complete response rates and long-term outcome was not superior to other intensive chemotherapy regimens.

Use of cryopreserved autologous cells for extracorporeal photochemotherapy: clinical applications.

BACKGROUND: Using autologous cryopreserved mononuclear cells (MNCs) for extracorporeal photochemotherapy (ECP) offers several advantages, such as treating patients from geographically distant care centers or maintaining ECP schedule while dramatically reducing number of apheresis sessions. We previously reported that cryopreserved cells retain their immunomodulatory properties when exposed to UVA and psoralen. To date, there are no clinical data on the use of cryopreserved MNCs for ECP ("cryo-ECP"). CASE REPORTS: Three patients were treated by cryo-ECP for refractory dermatomyositis, juvenile localized scleroderma, and acute graft-versus-host disease. For the first two patients, cryo-ECP aimed to reduce the number of apheresis sessions. Each cell product was split into three equal fractions: one was infused, and the other two were frozen for later infusion. The third patient was referred to our center from a hospital 700 km away. Fifteen apheresis procedures were performed during his stay: 12 were immediately treated and infused while three were cryopreserved. After discharge, the three cryopreserved bags were thawed, ECP-treated, and then sent back to the patient. CONCLUSION: In all three patients, cryo-ECP was safe and feasible. These cases illustrate promising clinical applications of the technique, opening perspectives for making ECP much more acceptable to patients while extending its indications.

[Reduced intensity allogenic hematopoietic stem cell transplantation in children]. / Allogreffe de cellules souches hématopoïétiques avec conditionnement à intensité réduite : indications et développement actuel en hématologie-oncologie pédiatrique.

Better understanding of the antitumor effect of allogeneic transplant and the need to reduce the toxicity of the procedure, particularly in elderly patients have spurred the development of reduced-intensity conditioning regimens (RIC). These regimens allow fast engraftment with very low chemotherapy-induced toxicity. They are widely used in adults and there are numerous studies to demonstrate their feasibility and efficiency, but in pediatrics, the place of RIC remains to be determined. They can be proposed in two pediatric populations. First, solid tumors or hematological malignancies remaining unresponsive to the reference strategies according to best practices in pediatrics. Second, in children presenting malignancies for which allografting is the only recognized curative indication but is contraindicated with myeloablative conditioning regimens. More than 100 pediatrics cases have been reported in various pathologies, including blood diseases, acute leukemia, Hodgkin's lymphoma and solid tumors, and promising results published recently underline how RIC warrants further investigation in prospective comparative multicentric trials. The use of new post-graft treatment modalities is expected to pave the way to the development of RIC in pediatric patients.