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Germline GATA2 mutations predispose to myeloid malignancies resulting from the progressive acquisition of additional somatic mutations. Here we describe clinical and biological features of 78 GATA2-deficient patients. Hematopoietic stem and progenitor cell phenotypic characterization revealed an exhaustion of myeloid progenitors. Somatic mutations in STAG2, ASXL1 and SETBP1 genes along with cytogenetic abnormalities (monosomy 7, trisomy 8, der(1;7)) occurred frequently in patients with GATA2 germline mutations. Patients were classified into three hematopoietic spectra based on bone marrow cytomorphology. No somatic additional mutations were detected in patients with normal bone marrow (spectrum 0), whereas clonal hematopoiesis mediated by STAG2 mutations was frequent in those with a hypocellular and/or myelodysplastic bone marrow without excess blasts (spectrum 1). Finally, SETBP1, RAS pathway and RUNX1 mutations were predominantly associated with leukemic transformation stage (spectrum 2), highlighting their implications in the transformation process. Specific somatic alterations, potentially providing distinct selective advantages to affected cells, are therefore associated with the clinical/hematological evolution of GATA2 syndrome. Our study not only suggests that somatic genetic profiling will help clinicians in their management of patients, but will also clarify the mechanism of leukemogenesis in the context of germline GATA2 mutations.

BackgroundIKZF1 gene deletion is an indicator of poor prognosis in childhood B-cell precursor acute lymphoblastic leukemia (BCP-ALL). The AEIOP/BFM group proposed that the prognostic strength of IKZF1 deletion could be remarkably improved by taking into account additional genetic deletions and reported that among patients with an IKZF1 deletion those with deletions in CDKN2A/2B, PAX5, or PAR1 in the absence of ERG deletion, grouped as IKZF1(plus), had the worst outcome. ProcedureBetween 1998 and 2008, 1636 patients under 18 years of age with previously untreated BCP-ALL were registered in the EORTC 58951 trial. Those with multiplex ligation-dependent probe amplification data were included in this analysis. Unadjusted and adjusted Cox model was used to investigate the additional prognostic value of IKZF1(plus). ResultsAmong 1200 patients included in the analysis, 1039 (87%) had no IKZF1 deletion (IKZF1(WT)), 87 (7%) had an IKZF1 deletion but not IKZF1(plus) (IKZF1(del)) and 74 (6%) had IKZF1(plus). In the unadjusted analysis, both patients with IKZF1(del) (hazard ratio [HR] = 2.10, 95% confidence interval [CI]: 1.34-3.31) and IKZF1(plus) (HR = 3.07, 95% CI: 2.01-4.67) had a shorter event-free survival compared with IKZF1(WT). However, although the IKZF1(plus) status was associated with patients' characteristics indicating poor prognosis, the difference between IKZF1(plus) and IKZF1(del) was not statistically significant (HR = 1.46, 95% CI: 0.83-2.57, p = .19). The results of the adjusted analysis were similar to the unadjusted analysis. ConclusionsIn patients with BCP-ALL from the EORTC 58951 trial, the improvement of the prognostic importance of IKZF1 by considering IKZF1(plus) was not statistically significant.

Resume But de l’etude Analyse de differents aspects psychologiques de la drepanocytose chez les sujets atteints. Plus specifiquement, nous nous interessons a l’impact de leur maladie, a l’adherence au traitement, aux emotions liees a leur maladie et a leur souhait d’education therapeutique. Patients et methode Nous soumettons l’adaptation du questionnaire « Brief Illness Perception Questionnaire » a des sujets atteints de 7 a 19 ans. Resultats L’echantillon compte 45 sujets, la majorite est issue du Congo. La moitie de nos sujets est issue de la premiere generation de migration. La majorite des sujets estime avoir une bonne sante. L’impact de la maladie sur leur quotidien a domicile est faible. Ils ont le sentiment de bien comprendre leur maladie. Globalement, ils ressentent des emotions variables en pensant a la drepanocytose. Ces emotions sont correlees a la migration. Ils associent difficilement au sujet de leur maladie. Conclusions La drepanocytose est vecue de maniere plutot positive. Les sujets severement atteints vont psychologiquement moins bien. De plus, la tristesse, la colere et la peur ressenties par rapport a la maladie sont correlees. La migration a un impact pejoratif important sur l’impact de la maladie chez nos sujets. La drepanocytose reste difficile a penser pour les sujets atteints. Il est capital de poursuivre le travail d’information societale, en Belgique et en Afrique.

Improved treatment landscape has led to better outcomes for paediatric acute lymphoblastic leukemia (ALL) survivors. As the number of survivors increase, we need to elucidate the long-term quality of life (QoL) and domains of complaints in these patients. Furthermore, the main priorities of these patients need to be clarified. We assessed long-term QoL outcomes of survivors of childhood ALL compared to matched population controls.QoL data were collected from survivors recruited in France and Belgium between 2012 and 2017, including the Short Form Health Survey (SF-12) and the Quality of Life Systemic Inventory (QLSI). The Wilcoxon test was used to compare SF-12 scale scores between survivors and matched population controls. For the QLSI, comparisons were mainly descriptive.One hundred and eighty-six survivors (mean age: 27.6 years; range: 18.1-52.8) at follow-up completed QoL measures, amongst whom 180 were matched to controls. Overall, survivors had higher QoL on all SF12 scale scores, indicating that they had better functioning compared to controls. Statistically significant differences on the SF12 were observed for Vitality, Social Functioning, Role Limitations due to Emotional Problems and Mental Health scales. QLSI outcomes suggested that survivors were happier than controls with Couple and Social Relations. Controls were unhappiest compared to survivors with Money, Love life, Self-esteem, Nutrition and Paid Work.Our findings suggest that survivors of childhood ALL have better QoL outcomes on some domains compared to the general population, specifically around social and emotional functioning, and that they tend to prioritize their relationships more. Interventions for improving QoL outcomes, might build on existing positive experiences with family, friends and partners.

Neutropenia and neutrophil dysfunction found in deficiencies in G6PC3 and in the glucose-6-phosphate transporter (G6PT/SLC37A4) are due to accumulation of 1,5-anhydroglucitol-6-phosphate (1,5-AG6P), an inhibitor of hexokinase made from 1,5-anhydroglucitol (1,5-AG), an abundant polyol present in blood. Lowering blood 1,5-AG with an SGLT2 inhibitor greatly improved neutrophil counts and function in G6PC3-deficient mice and in patients with G6PT-deficiency. We evaluate this treatment in two G6PC3-deficient children. While neutropenia was severe in one child (PT1), which was dependent on granulocyte cololony-stimulating factor (GCSF), it was significantly milder in the other one (PT2), which had low blood 1,5-AG levels and only required GCSF during severe infections. Treatment with the SGLT2-inhibitor empagliflozin decreased 1,5-AG in blood and 1,5-AG6P in neutrophils and improved (PT1) or normalized (PT2) neutrophil counts, allowing to stop GCSF. On empagliflozin, both children remained infection-free (>1 year - PT2; >2 years - PT1) and no side effects were reported. Remarkably, sequencing of SGLT5, the gene encoding the putative renal transporter for 1,5-AG, disclosed a rare heterozygous missense mutation in PT2, replacing the extremely conserved Arg401 by a histidine. The higher urinary clearance of 1,5-AG explains the more benign neutropenia and the outstanding response to empagliflozin treatment found in this child. Our data shows that SGLT2 inhibitors are an excellent alternative to treat the neutropenia present in G6PC3-deficiency.

Introduction. — The recently identified role of a BRAF somatic mutation in the pathophysiologyof Langerhans cell histiocytosis (LCH) offers new therapeutic options. Herein we describe thecase of a 10-month-old infant with refractory high-risk LCH successfully treated with vemu-rafenib.Observation. — The patient first presented with cutaneous LCH at the age of 2 months. Thedisease remained undiagnosed until she was 6 months old, when it rapidly evolved to a multisys-temic high-risk and life-threatening disease, refractory to 2 lines of chemotherapy. BRAFV600Emutation was found at skin biopsy, and targeted therapy with vemurafenib was started whenshe was 10 months old. The treatment induced a fast and sustained response, but rapid relapseoccurred after treatment discontinuation, leading to resumption of treatment, once moreresulting in a sustained response.Conclusion. — Our case highlights the first-line role of dermatologists in establishing the diag-nosis of LCH, especially in children, in whom the eruption may be difficult to identify, leading todelayed diagnosis. Targeted therapy with vemurafenib has recently been described in children in this indication and our results support its efficacy, highlighting the need for prolonged treat-ment and raising the question of maintenance therapy, as well as the necessity for large-scaleand long-term studies., info:eu-repo/semantics/published

High-throughput sequencing (HTS) of the immunoglobulin heavy chain (IgH) locus is a recent very efficient technique to monitor minimal residual disease of B-cell precursor acute lymphoblastic leukemia (BCP-ALL). It also reveals the sequences of clonal rearrangements, therefore, the multiclonal structure, of BCP-ALL. In this study, we performed IgH HTS on the diagnostic bone marrow of 105 children treated between 2004 and 2008 in Belgium for BCP-ALL in the European Organization for Research and Treatment of Cancer (EORTC)-58951 clinical trial. Patients were included irrespectively of their outcome. We described the patterns of clonal complexity at diagnosis and investigated its association with patients’ characteristics. Two indicators of clonal complexity were used, namely, the number of foster clones, described as clones with similar D-N2-J rearrangements but other V-rearrangement and N1-joining, and the maximum across all foster clones of the number of evolved clones from one foster clone. The maximum number of evolved clones was significantly higher in patients with t(12;21)/ETV6:RUNX1. A lower number of foster clones was associated with a higher risk group after prephase and t(12;21)/ETV6:RUNX1 genetic type. This study observes that clonal complexity as accessed by IgH HTS is linked to prognostic factors in childhood BCP-ALL, suggesting that it may be a useful diagnostic tool for BCP-ALL status and prognosis.

STUDY QUESTION What are the fertility outcomes of male and female childhood acute lymphoblastic leukaemia (ALL) long-term survivors? SUMMARY ANSWER We observed similar fertility outcomes in both male and female childhood ALL survivors compared with the general population, with the exception of a higher proportion of miscarriages among partners of male survivors. WHAT IS KNOWN ALREADY Survival after childhood ALL is currently >90% and fertility impairments are among the main concerns of the long-term survivors. Few studies have focused on the fertility issues within this selected population and the existing data are difficult to interpret due to the different treatment regimens received by the patients, the small sample sizes and the unavailability of control data in many studies. STUDY DESIGN, SIZE, DURATION Childhood ALL patients enrolled in European Organisation for Research and Treatment of Cancer (EORTC) studies between 1971 and 1998 in France and Belgium, PARTICIPANTS/MATERIALS, SETTING, METHODS Survivors and controls were invited to fill out a questionnaire including information about their menstrual cycles (for females), intention to have children, having children, use of medical help to become pregnant and occurrence of negative pregnancy outcomes (birth defect, miscarriage, medical abortion or stillbirth). The results were analysed separately for females and males. The association between age at diagnosis and fertility outcomes, adjusted by age at follow-up, study and country were investigated using logistic regression. MAIN RESULTS AND THE ROLE OF CHANCE The median time since diagnosis was 20.1 years and the median age at follow-up was 25 years. There were 144 survivors (97 females, 47 males) who wanted to have children. Among these, craniospinal radiotheraphy (CRT) and haematopoietic stem cell transplantation (HSCT) were administered to 18% and 4%, respectively. Of these who tried to have children, 75% of females and 69% of males succeeded, compared with 72% and 61% of the controls, respectively. These differences were not statistically significant (P = 0.73 for females and P = 0.50 for males). Overall, fertility outcomes were comparable between survivors and controls, except that a higher proportion of miscarriages occurred in partners of male survivors (28.1% versus 5.9%, P = 0.021). Among female survivors, an older age at diagnosis (10–17 years) was associated with a greater risk of pregnancy problems (adjusted OR 5.61, P = 0.046). LIMITATIONS, REASONS FOR CAUTION The interpretation of the incidence of miscarriage among the partners of male survivors is limited by the lack of data regarding the males’ partners and by a possibly higher tendency to recall and disclose fertility issues among male survivors compared with male controls. WIDER IMPLICATIONS OF THE FINDINGS Fertility outcomes were similar in childhood ALL survivors and controls, and the low proportion of patients treated with CRT or HSCT might explain this. Further studies should confirm the higher proportion of miscarriages in partners of male survivors. STUDY FUNDING/COMPETING INTEREST(S) This publication was supported by donations from the Fonds Cancer (FOCA) from Belgium and the KU Leuven from Belgium. G.R. has been awarded a fellowship by the EORTC Cancer Research Fund (ECRF). C.P. has been awarded a fellowship by Fonds Cancer (FOCA) from Belgium and the Kinderkankerfonds from Belgium (a non-profit childhood cancer foundation under Belgian law). No competing interests were declared. TRIAL REGISTRATION NUMBER NCT01298388 (clinicaltrials.gov).

PURPOSE Off-label use of vemurafenib (VMF) to treat BRAFV600E mutation–positive, refractory, childhood Langerhans cell histiocytosis (LCH) was evaluated. PATIENTS AND METHODS Fifty-four patients from 12 countries took VMF 20 mg/kg/d. They were classified according to risk organ involvement: liver, spleen, and/or blood cytopenia. The main evaluation criteria were adverse events (Common Terminology Criteria for Adverse Events [version 4.3]) and therapeutic responses according to Disease Activity Score. RESULTS LCH extent was distributed as follows: 44 with positive and 10 with negative risk organ involvement. Median age at diagnosis was 0.9 years (range, 0.1 to 6.5 years). Median age at VMF initiation was 1.8 years (range, 0.18 to 14 years), with a median follow-up of 22 months (range, 4.3 to 57 months), whereas median treatment duration was 13.9 months (for 855 patient-months). At 8 weeks, 38 complete responses and 16 partial responses had been achieved, with the median Disease Activity Score decreasing from 7 at diagnosis to 0 ( P < .001). Skin rash, the most frequent adverse event, affected 74% of patients. No secondary skin cancer was observed. Therapeutic plasma VMF concentrations (range, 10 to 20 mg/L) seemed to be safe and effective. VMF discontinuation for 30 patients led to 24 LCH reactivations. The blood BRAFV600E allele load, assessed as circulating cell-free DNA, decreased after starting VMF but remained positive (median, 3.6% at diagnosis, and 1.6% during VMF treatment; P < .001) and was associated with a higher risk of reactivation at VMF discontinuation. None of the various empirical therapies (hematopoietic stem-cell transplantation, cladribine and cytarabine, anti-MEK agent, vinblastine, etc) used for maintenance could eradicate the BRAFV600E clone. CONCLUSION VMF seemed safe and effective in children with refractory BRAFV600E-positive LCH. Additional studies are needed to find effective maintenance therapy approaches.

Outcomes in childhood T-cell acute lymphoblastic leukaemia (T-ALL) are steadily improving due to intensive therapy. Between 1989 and 2008, 599 children with newly diagnosed T-ALL were enrolled in two successive European Organization for Research and Treatment of Cancer - Children's Leukaemia Group trials (58881 and 58951), both based on the Berlin-Frankfurt-Munster protocol and without cranial irradiation. In the latter trial induction chemotherapy was intensified. The most important randomizations were Medac Escherichia coli asparaginase versus Erwinia asparaginase in trial 58881, and dexamethasone (6 mg/m2/day) versus prednisolone (60 mg/m2/day) and prolonged versus conventional asparaginase duration in trial 58951. 8-year event-free survival (EFS) increased from 65·1% to 74·0% in trial 58951. Improvement was most profound for patients with white blood cell (WBC) counts, SCOPUS: ar.j, info:eu-repo/semantics/published

Objective: Study of the psychological development of eight children aged 6 to 12 years and suffering from sickle cell anemia. Methodology: Individual and family interviews with the children and their parents. Emotional, intellectual evaluation of the medical, family and social context using psychometric tools (WISC-IV, MDI-C, AUQUEI), a semi-directive interview and projective media (drawing, modeling, CAT, CAT-S). Results: The children evaluate their quality of life as good. Except for a self-reported low energy level, the disease seems globally not invasive. Two children, however, show depression with anxiety on the depression scale. Concerning their psychological development, the children have a regular intellectual functioning and a school curriculum without any particularity. Faced with the issue of the disease, there are communication difficulties as well for the children as for their families. The authors observe a traumatic reaction for the parents. In the context of the disease, the children present an inhibited level of mental elaboration (avoidance) which differs little from that of their parents and family. The psychic adjustments in the relational field are of good quality but the children scarcely unfold and display their imagination (they tend to cling to reality and have little access to their personal fantasy life). They present anxiety related to separation-differentiation processes and a need for relational support. Conclusion: Despite the difficulties in subjective appropriation of the disease and empowerment-individuation problems, the children's defensive mechanisms are diversified and operational. Their defensive mechanisms, as well as their creativity, fluctuate with the investigation tools used during the testing situation. This observation leads the authors to underline the interest of varying the evaluation tools in order to be able to observe all the child's resources to cope with its sickle cell anemia., SCOPUS: ar.j, info:eu-repo/semantics/published

IntroductionJuvenile idiopathic arthritis (JIA) represents a very heterogeneous disease. As such, it has been a challenge to describe the disease activity of JIA cohorts. Our objective was to describe the first Belgian cohort of children with JIA by assessing their disease characteristics, outcomes, and potential markers of prognosis.MethodsThe CAP48 cohort is a multicentric observational study of children with recent or well-established diagnosis of JIA (naïve or not to treatment at baseline), evaluated every 3 to 6 months during a follow-up of 10 years.ResultsThere were 125 children included, composing of 25 naïve and 100 established patients. Their median age at onset was 6.2 and 4.2 years in the naïve and established cohort respectively, with a predominance of female. All subtypes of JIA were represented in both cohorts. The mean DAS28-CRP and JADAS10-CRP at baseline in naïve patients was 2.52 and 6.0 respectively. Uveitis occurred in 19% of patients and was strongly associated with presence of antinuclear antibodies (odds ratio of 6). Among naïve patients, 55% were in remission at 12 months according to ACR criteria and JADAS10 scores, in contrast with 100% achieving DAS28 remission. ConclusionThis first cohort study in Belgium allowed to compare its data to other existing cohorts and to evaluate quality of care in Belgian French-speaking hospitals. Additionally, it highlighted a superiority of JADAS10 over DAS28 to monitor and evaluate remission in JIA. This study also underlined a need for more accurate markers of prognosis to improve treatment and long-term outcomes.

Infant acute lymphoblastic leukemia (ALL) is characterized by a high incidence ofMRD was measured in 249 infants by DNA-based polymerase chain reaction of rearrangedEOI MRD levels predicted outcome with 6-year disease-free survival (DFS) of 60.2% (95% CI, 43.2 to 73.6), 45.0% (95% CI, 28.3 to 53.1), and 33.8% (95% CI, 23.8 to 44.1) for infants with negative, intermediate, and high EOI MRD levels, respectively (This study provides support for the idea that induction therapy selects patients for subsequent therapy; infants with high EOI MRD may benefit from AML-like consolidation (DFS 45.9%

Background Little is known about characteristics of seasonal human coronaviruses (HCoVs) (NL63, 229E, OC43, and HKU1) after allogeneic stem cell transplantation (allo-HSCT). Methods This was a collaborative Spanish and European bone marrow transplantation retrospective multicenter study, which included allo-HSCT recipients (adults and children) with upper respiratory tract disease (URTD) and/or lower respiratory tract disease (LRTD) caused by seasonal HCoV diagnosed through multiplex polymerase chain reaction assays from January 2012 to January 2019. Results We included 402 allo-HSCT recipients who developed 449 HCoV URTD/LRTD episodes. Median age of recipients was 46 years (range, 0.3–73.8 years). HCoV episodes were diagnosed at a median of 222 days after transplantation. The most common HCoV subtype was OC43 (n = 170 [38%]). LRTD involvement occurred in 121 episodes (27%). HCoV infection frequently required hospitalization (18%), oxygen administration (13%), and intensive care unit (ICU) admission (3%). Three-month overall mortality after HCoV detection was 7% in the whole cohort and 16% in those with LRTD. We identified 3 conditions associated with higher mortality in recipients with LRTD: absolute lymphocyte count Conclusions Seasonal HCoV after allo-HSCT may involve LRTD in many instances, leading to a significant morbidity.

Genetic subgroups; Immune reconstitution; Pretransplantation infections Subgrupos genéticos; Reconstitución inmune; Infecciones previas al trasplante Subgrups genètics; Reconstitució immune; Infeccions prèvies al trasplantament Background Hematopoietic stem cell transplantation (HSCT) represents a curative treatment for patients with severe combined immunodeficiency (SCID), a group of monogenic immune disorders with an otherwise fatal outcome. Objective We performed a comprehensive multicenter analysis of genotype-specific HSCT outcome, including detailed analysis of immune reconstitution (IR) and the predictive value for clinical outcome. Methods HSCT outcome was studied in 338 patients with genetically confirmed SCID who underwent transplantation in 2006-2014 and who were registered in the SCETIDE registry. In a representative subgroup of 152 patients, data on IR and long-term clinical outcome were analyzed. Results Two-year OS was similar with matched family and unrelated donors and better than mismatched donor HSCT (P < .001). The 2-year event-free survival (EFS) was similar in matched and mismatched unrelated donor and less favorable in mismatched related donor (MMRD) HSCT (P < .001). Genetic subgroups did not differ in 2-year OS (P = .1) and EFS (P = .073). In multivariate analysis, pretransplantation infections and use of MMRDs were associated with less favorable OS and EFS. With a median follow-up of 6.2 years (range, 2.0-11.8 years), 73 of 152 patients in the IR cohort were alive and well without Ig dependency. IL-2 receptor gamma chain/Janus kinase 3/IL-7 receptor–deficient SCID, myeloablative conditioning, matched donor HSCT, and naive CD4 T lymphocytes >0.5 × 10e3/μL at +1 year were identified as independent predictors of favorable clinical and immunologic outcome. Conclusion Recent advances in HSCT in SCID patients have resulted in improved OS and EFS in all genotypes and donor types. To achieve a favorable long-term outcome, treatment strategies should aim for optimal naive CD4 T lymphocyte regeneration.

SARS-CoV-2 causes a hypercoagulable state that predisposes patients to thromboembolic events. We report two adolescents with Sickle Cell Disease (SCD) who developed pulmonary embolism (PE) during acute chest syndrome (ACS) episode associated with a possible SARS-CoV-2 infection. Both SCD and SARS-CoV-2 infection predisposes to thromboembolic disease. Thromboprophylaxis with LMWH should be considered in adolescent with ACS, related or not to COVID-19 disease.

Aim To evaluate the prognostic significance of initial central nervous system (CNS) involvement of children with acute lymphoblastic leukemia (ALL) enrolled in the EORTC 58951 trial. Patients and methods From 1998 to 2008, 1930 ALL patients were included in the randomized EORTC 58951 trial. Overall treatment intensity was adjusted according to known prognostic factors including the level of minimal residual disease after induction treatment. CNS-directed therapy comprised four to 11 courses of i.v. methotrexate (5 g/m2), and 10 to 19 intrathecal chemotherapy injections, depending on risk group and CNS status. Cranial irradiation was omitted for all patients. Results The overall 8-year event-free survival (EFS) and overall survival (OS) rates were 81.3% and 88.1%, respectively. In the CNS-1, TPL+, CNS-2, and CNS-3 groups, the 8-year EFS rates were 82.1%, 77.1%, 78.3%, and 57.4%, respectively. Multivariable analysis indicated that initial CNS-3 status, but not CNS-2 or TLP+, was an independent adverse predictor of outcome. The 8-year incidence of isolated CNS relapse was 1.7% and of isolated or combined CNS relapse it was 3.7%. NCI high-risk group, male sex, CNS-2 and CNS-3 status were independent predictors for a higher incidence of any CNS relapse. Conclusions CNS-3 status remains associated with poor prognosis and requires intensification of both systemic and CNS-directed therapy. This trial was registered at https://clinicaltrials.gov/under/NCT00003728 .

Objective Type I IFNs play a well-known role in the pathogenesis of SLE, through activation of CD4 T and antigen-presenting cells. Here, we investigated the effects of IFN alpha (IFNα) on SLE B cell activation and differentiation. Methods Peripheral blood mononuclear cells (PBMCs) and purified total or naïve B cells were obtained from healthy controls and SLE patients. The effects of IFNα on B cell differentiation were studied by flow cytometry. The role of STAT3 in B cell responses to IFNα was studied using pharmacological inhibitors and PBMCs from STAT3-deficient individuals. Results Incubation of normal PBMCs with IFNα induces a B cell differentiation pattern as observed spontaneously in SLE PBMCs. IFNα displays direct stimulatory effects on purified naïve B cells from healthy individuals, as evidenced by a significant induction of cell surface CD38 and CD95 in the presence of the cytokine. In purified naïve B cells, IFNα also induces STAT3 phosphorylation. IFNα-induced naïve B cell differentiation in total PBMCs is significantly inhibited in the presence of STAT3 inhibitors, or in PBMCs from individuals with STAT3 loss of function mutations. Spontaneous levels of STAT3, but not STAT1, phosphorylation are significantly higher in total B cells from SLE patients compared with controls. Pharmacological STAT3 inhibition in SLE PBMCs inhibits naïve B cell activation and differentiation. Conclusion IFNα displays direct stimulatory effects on B cell differentiation and activation in SLE. STAT3 phosphorylation mediates the effects of IFNα stimulation in naïve B cells, an observation that opens new therapeutic perspectives in SLE.

BACKGROUND Chronic transfusion in sickle cell disease (SCD) remains the gold standard therapy for stroke prevention and for patients with severe disease despite adequate hydroxyurea treatment. The aim of our study was to assess the safety and efficacy of automated red blood cell exchange (aRBX) in patients with SCD previously treated with manual exchange transfusion (MET). Costs related to transfusion and chelation overtime were evaluated. STUDY DESIGN AND METHODS Beginning in January 2012, children with SCD who weighed 30 kg or more on MET could switch to aRBX. Clinical, biological, and procedures' data, including costs, were recorded for the last 6 months on MET and compared to those after the first and the second year on aRBX. RESULTS Ten patients switched from MET to aRBX at a median age of 11.8 years. After the switch, median hemoglobin S (HbS) increased significantly (33.5% on MET compared to 45% on aRBX; p

Background: Infant acute lymphoblastic leukemia (ALL) is a rare disease with dismal outcome. While outcomes for older children have improved, with event-free survival (EFS) currently above 85%, newly diagnosed infants ( Methods: We conducted a prospective, single-arm, international, multicenter, phase 2 study. Newly diagnosed patients 0.05% before OCTADAD and all HR patients in complete remission were eligible for HSCT. (Serious) Adverse Events ((S)AEs) were collected from the start of blinatumomab until the next treatment block. Outcome data were compared to historical controls. Results: Twenty-eight patients were enrolled. Baseline characteristics are shown in Table 1. The median follow-up was 11 months (range 1.5-33 months). All patients received the full course of blinatumomab without treatment interruptions. Seven SAEs were reported during blinatumomab (3 fever, grade 1 and 4 infections, grade 3-4). None of the patients experienced neurological (S)AEs. In total, 70 AEs were reported, the most frequent grade >3 adverse events were febrile neutropenia (n= 2), anemia (n=5), and elevated GGT (n=2). MRD negative complete response occurred in 54% (n=15/28) at TP blina1, as well as at TP blina2 (after 2 and 4 weeks of blinatumomab, Table 2), which tended to be higher compared to the end of consolidation in Interfant06 (40%, p=0.16). There were 89% (25/28) of patients who were MRD negative or not quantifiable ( Conclusion: This is the first trial to use blinatumomab in infants with newly diagnosed KMT2A-r ALL. Blinatumomab added to the Interfant06 backbone was very well tolerated, and has promising efficacy in terms of a high rate of complete MRD response and short term EFS. Longer follow-up is awaited, but the low relapse rate after blinatumomab is remarkable, given that in historical controls relapses occur frequently and early, during therapy. Given these findings, blinatumomab will be implemented for all infants with newly diagnosed KMT2A-r ALL in the next Interfant21 protocol. Figure 1 Figure 1. Disclosures Nysom: Y-mAbs: Consultancy, Membership on an entity's Board of Directors or advisory committees, Other: teaching; EUSA Pharma: Membership on an entity's Board of Directors or advisory committees; Bayer: Membership on an entity's Board of Directors or advisory committees, Other: teaching. Biondi: Amgen: Honoraria; Incyte: Consultancy, Other: Advisory Board; Bluebird: Other: Advisory Board; Novartis: Honoraria; Colmmune: Honoraria. OffLabel Disclosure: Investigational use of blinatumomab

Introduction Allogeneic hematopoietic stem cell transplantation (HSCT) is a curative therapy for sickle cell disease (SCD) allowing a SCD-free survival over 95% among children with matched HLA-identical donor (Gluckman E. Blood, 2017; Bernaudin F. Haematologica, 2020). In adults, myeloablative HSCT is associated with more graft-versus host disease (GVHD) and higher toxicity (Cappelli B. Haematologica, 2019). More recent approaches using non myeloablative (NMA) conditioning regimen (3 gray (Gy) total body irradiation (TBI) plus alemtuzumab) followed by HLA-identical peripheral blood stem cells (PBSC) and post-transplant sirolimus appear safe in adults (Hsieh MM. JAMA, 2014), but incidence of graft failure might be higher than the one reported after myeloablative conditioning (MAC) (Alzahrani M. Br J Haematol, 2021). Here, we compare outcomes after MAC or NMA conditioning regimens in patients over 15 years old transplanted from a matched related donor (MRD). Patients and methods All consecutive patients transplanted for SCD from a MRD from January 2015 to October 2020 were eligible if they were over 15 years old and received a busulfan-based MAC conditioning regimen or a NMA conditioning regimen. Chimerism was studied by analyzing various polymorphisms after polymerase chain reaction (PCR) amplification of DNA obtained from whole blood cells. Rejection was defined as donor chimerism Results Thirty-four patients were included: 20 in the MAC and 14 in the NMA groups. Median age at transplant was 17 years (range 15-46) without difference between groups. Forty four percent of patients had a history of cerebral vasculopathy, 79% of recurrent vaso-occlusive crises and 76% of acute chest syndrome. ABO major incompatibility was present in 15% of patients. There was no difference in patient characteristics according to the conditioning regimen group except for pre-transplant cerebral vasculopathy, more frequently reported in the MAC group: 70% versus 6% in the NMA group (p In the MAC group, conditioning regimen associated busulfan (12.8 mg/kg IV), cyclophosphamide (N=17) or fludarabine (N= 3) and anti-thymoglobulin (ATG, mostly 20mg/kg). Stem cell source was bone marrow and post-transplant immunosuppression combined cyclosporine and mycophenolate or methotrexate. In the NMA group, conditioning regimen associated 3Gy TBI and alemtuzumab (1mg/kg), followed by PBSC and post-transplant sirolimus. All patients engrafted and no secondary graft failure was observed. One MAC group patient died from GVHD. The 2-year overall and EFS were 95% (CI 95%: 85.9-100) in the MAC group (median follow-up of 39 months (range 8-63)) and 100% (CI 95%: 100-100) in the NMA group (median follow-up of 17 months (range 9-39)). Incidence of grade II-IV acute GVHD was 0% in the NMA group versus 20% in the MAC group (p=0.12). Incidence of chronic GVHD was 0% in the NMA group versus 25% in the MAC group (p=0.06). From the 27 patients with follow-up>12 months, 17/17 discontinued immunosuppressive therapy in the MAC group versus 8/10 in the NMA group. Hematopoietic recovery was faster in the NMA group with less platelet and red blood cell units transfused (Table). Throughout the follow-up, median donor chimerism was higher after MAC transplantation than after NMA transplantation: 98% (range 69-100) and 86 % (range 50-97) respectively at 1 year (p=0.017). Donor chimerism remained above 50% throughout the follow-up in all patients except 1 of the NMA group who displayed stable chimerism between 40 and 50%. All patients achieved HbS level close to the one of their donors. There was no difference between the 2 groups regarding occurrence of infections. MAC transplant was more often associated with hypertension, neurological complications, severe mucositis and need of enteral or parenteral nutrition. Moreover, duration of hospitalization was longer in MAC group: 54 days (range 39-192) versus 35 days in the NMA group (range 21-52) (p Conclusion In this series of adolescents and adults transplanted for SCD, the survival without SCD was excellent with a faster hematological recovery and a lower toxicity after NMA HSCT. Longer follow-up is required to confirm stable mixed donor chimerism and the cure of SCD after NMA approach. Figure 1 Figure 1. Disclosures Joseph: bluebird bio: Consultancy. Boissel: Servier: Consultancy, Honoraria; JAZZ Pharma: Honoraria, Research Funding; Incyte: Honoraria; Amgen: Consultancy, Honoraria, Research Funding; SANOFI: Honoraria; CELGENE: Honoraria; Novartis: Consultancy, Honoraria, Research Funding; Bristol-Myers Squibb: Honoraria, Research Funding; PFIZER: Consultancy, Honoraria. Pondarré: ADDMEDICA: Honoraria.

The Belgian sickle cell disease registry (BCR) was initiated in 2008 and aims to evaluate mortality, morbidity as well as clinicals practices in participating centers. The current analysis focuses on criteria influencing age at transplantation (HSCT) and on the management of Hydroxyurea (HU) therapy across centers. The methodology of the registry has already been published (Le PQ et al., Pediatric Blood and Cancer, 2015) . Data are recorded prospectively from neonatal screening or first contact until last annual follow-up (FU) or death. The data collected included diagnosis, demography, treatment and outcome data as well as a minimal set of biological values. Data were extracted from the database in May 2021. There are 1029 patients registered by 14 different centers (2 centers exclusively treating adult patients). The median FU is 9 y (1-53 y). Median age at last FU is 13 y (0-61 y). 890 patients (86,5%) have a severe phenotype (SS or Sβ°) and 52% are female. Among them, 561 (55%) are born in Belgium of whom 379 (68%) are diagnosed by neonatal screening. In the absence of neonatal screening, median age at diagnosis is 1 year (range 0-18). 131 patients have been transplanted (126 successfully), 68 HSCT were performed before 2005. At last FU, 646 patients (76%) received at least 1 disease-modifying treatment (DMT) : 598 patients receive HU, 65 are chronically transfused, 8 participate in a study with crizanlizumab. The prescribed HU dose is known for 572 patients. 179 patients (31.3%) receive less than 20 mg/kg/day, 217 (37.9%) less than 25 mg/kg/day, 148 (25.9%) less than 30 mg/kg/day and 28 (4.9%) were prescribed more than 30 mg/kg/day. The majority of HSCT were performed in two centers (68 and 59, respectively). Median age at HSCT was significantly different between both centers (8y (2-15) versus 5y (0-19); p=0.002) (figure 1). Variables associated with a lower age at HSCT are detailed in table 1. In a linear multivariate regression model, birth in Belgium (p=0.002), no treatment with HU (p=0.009) and shorter duration of FU (p Among not transplanted patients, the proportion of those receiving HU is different between centers (50% to 91%; p=0.050). The median age at which HU was initiated was also significantly different between centers (4y to 21y; p Twenty-seven (2.6%) patients died which accounted for a mortality rate of 0.24/100 patients-years (PY) which increases significantly with age (0.18/100PY 40 years; p=0.001). Conclusions: BSR has an excellent registration activity from participating centers and represents a reliable tool to evaluate the Belgian SCD population. Mortality remains low with a significant trend to increase with age. Regarding treatment practices, the age at start of HU is significantly different between centers as the approach to further HU treatment, evaluated by ΔMCV. A higher dose of HU resulted in a higher ΔMCV. However, the policy to increase HU to maximal tolerated dose seems not implemented in most centers, as 2/3 of the patients are prescribed less than 25 mg/kg/day. Being born in Belgium and no treatment with HU are associated with younger age at HSCT. Nevertheless since 2005, almost all patients were treated with HU prior HSCT, reflecting the wider implementation of HU in SCD patients living in Belgium. Figure 1 Figure 1. Disclosures Benghiat: Novartis: Consultancy; BMS: Consultancy. Labarque: Bayer: Consultancy; Sobi: Consultancy; NovoNordisk: Consultancy; Octapharma: Consultancy; Novartis: Consultancy.

Asparaginase is an essential component of combination chemotherapy for childhood acute lymphoblastic leukemia and non-Hodgkin lymphoma. The value of asparaginase was further addressed in a group of non-very high-risk patients by comparing prolonged (long-asparaginase) versus standard (short-asparaginase) native E. coli asparaginase treatment in a randomized part of the phase III 58951 trial of the European Organization for Research and Treatment of Cancer Children’s Leukemia Group. The main endpoint was disease-free survival. Overall, 1,552 patients were randomly assigned to long-asparaginase (775 patients) or short-asparaginase (777 patients). Patients with grade ≥2 allergy to native E. coli asparaginase were switched to equivalent doses of Erwinia or pegylated E. coli asparaginase. The 8-year disease-free survival rate (±standard error) was 87.0±1.3% in the long-asparaginase group and 84.4±1.4% in the short-asparaginase group (hazard ratio: 0.87; P=0.33) and the 8-year overall survival rate was 92.6±1.0% and 91.3±1.2% respectively (hazard ratio: 0.89; P=0.53). An exploratory analysis suggested that the impact of long-asparaginase was beneficial in the National Cancer Institute standard-risk group with regards to disease-free survival (hazard ratio: 0.70; P=0.057), but far less so with regards to overall survival (hazard ratio: 0.89). The incidences of grade 3–4 infection during consolidation (25.2% versus 14.4%) and late intensification (22.6% versus 15.9%) and the incidence of grade 2–4 allergy were higher in the long-asparaginase arm (30% versus 21%). Prolonged native E. coli asparaginase therapy in consolidation and late intensification for our non-very high-risk patients did not improve overall outcome but led to an increase in infections and allergy. This trial was registered at www.clinicaltrials.gov as #NCT00003728.

Asparaginase (ASNase) is an important anti-leukaemic drug in the treatment of childhood acute lymphoblastic leukaemia (ALL) and non-Hodgkin lymphoma (NHL). A substantial proportion of patients develop hypersensitivity reactions with anti-ASNase neutralising antibodies, resulting in allergic reactions or silent inactivation (SI), and characterised by inactivation and rapid clearance of ASNase. We report results of a prospective, real-time therapeutic drug monitoring of pegylated Escherichia coli (PEG-)ASNase and Erwinia ASNase in children treated for ALL and NHL in Belgium. Erwinia ASNase was given as second-line after hypersensitivity to PEG-ASNase. In total, 286 children were enrolled in the PEG-ASNase cohort. Allergy was seen in 11¸2% and SI in 5·2% of patients. Of the 42 patients treated with Erwinia ASNase, 7·1% experienced allergy and 2·4% SI. The median trough PEG-ASNase activity was high in all patients without hypersensitivity. After Erwinia administration significantly more day 3 samples had activities, SCOPUS: ar.j, info:eu-repo/semantics/published

Neutropenia represents an important problem in patients with genetic deficiency in either the glucose-6-phosphate transporter of the endoplasmic reticulum (G6PT/SLC37A4) or G6PC3, an endoplasmic reticulum phosphatase homologous to glucose-6-phosphatase. While affected granulocytes show reduced glucose utilization, the underlying mechanism is unknown and causal therapies are lacking. Using a combination of enzymological, cell-culture, and in vivo approaches, we demonstrate that G6PT and G6PC3 collaborate to destroy 1,5-anhydroglucitol-6-phosphate (1,5AG6P), a close structural analog of glucose-6-phosphate and an inhibitor of low-KM hexokinases, which catalyze the first step in glycolysis in most tissues. We show that 1,5AG6P is made by phosphorylation of 1,5-anhydroglucitol, a compound normally present in human plasma, by side activities of ADP-glucokinase and low-KM hexokinases. Granulocytes from patients deficient in G6PC3 or G6PT accumulate 1,5AG6P to concentrations (∼3 mM) that strongly inhibit hexokinase activity. In a model of G6PC3-deficient mouse neutrophils, physiological concentrations of 1,5-anhydroglucitol caused massive accumulation of 1,5AG6P, a decrease in glucose utilization, and cell death. Treating G6PC3-deficient mice with an inhibitor of the kidney glucose transporter SGLT2 to lower their blood level of 1,5-anhydroglucitol restored a normal neutrophil count, while administration of 1,5-anhydroglucitol had the opposite effect. In conclusion, we show that the neutropenia in patients with G6PC3 or G6PT mutations is a metabolite-repair deficiency, caused by a failure to eliminate the nonclassical metabolite 1,5AG6P., SCOPUS: ar.j, info:eu-repo/semantics/published

SCOPUS: no.j, info:eu-repo/semantics/published

SCOPUS: ar.j, info:eu-repo/semantics/published

Background Asparaginase (Asp) and corticosteroid (CS) treatment in patients with acute lymphoblastic leukaemia (ALL) is associated with an increased risk of thrombotic events. Objective Characterization of global haemostatic phenotypes of patients with ALL during Asp therapy. Procedure Thrombin generation (TG) was monitored in platelet-poor plasma of 56 children treated for a B lineage ALL (36 with native, 20 with PEG Asp) using 1 pM tissue factor and 4 μM phospholipids, with and without thrombomodulin. Protein C activity (PC), free protein S (PS), antithrombin (AT) and fibrinogen levels were also measured. Results Elevated endogenous thrombin potential (ETP) and peak of TG were noted at diagnosis, throughout the Induction phase and Late Intensification but was significantly less for PEG than for native Asp (P < 0.001), while age, sex, type of corticosteroid during Induction and molecular response had no significant effect. The reduction of ETP after addition of thrombomodulin was significantly lower in ALL children compared with that in controls, suggesting impairment in PS/PC pathway. Three patients experienced thrombosis: two treated with native and one with PEG Asp. The two patients with native Asp had, at the time of thrombosis, a prothrombotic profile. Conclusions Treatment with Asp, in combination with CS, enhances TG in children with ALL, more significantly with native than PEG Asp, which is present early at diagnosis, persists during Induction and reappears during Late Intensification. This is consistent with the high incidence of thrombotic events described during these phases of therapy. The less pronounced effect of PEG Asp remains to be elucidated.

Correction to: Leukemia (2016); 30(5), 1184–1187; doi:10.1038/leu.2015.246 Following the publication of this article the authors noted that the labels in Figures 1b and d have been switched. The correct labels in Figure 1b are; mixed lineage leukemia rearranged (MLL rearranged; dotted line) and unknown (thin solid line).

Objective To evaluate the survival of patients with sickle cell disease (SCD) recorded in the Belgian SCD Registry and to assess the impact of disease-modifying treatments (DMT). Method The Registry created in 2008 included patients of eight centers. All available data in 2008 were retrospectively encoded in the database. After 2008 and until 2012, all data were recorded prospectively for already registered patients as well as newly diagnosed subjects. Data were registered from neonatal screening or from diagnosis (first contact) until last follow-up or death. Data included diagnosis, demography, and outcome data. Results We collected data from 469 patients over a 5,110 patient years (PY) follow-up period. The global mortality rate was low (0.25/100 PY), although 13 patients died (2.8%) and was similar between children, adolescents (10–18 years), and young adults (P = 0.76). Out of the cohort, 185 patients received hydroxyurea at last follow-up (median duration of treatment: 10.3 years), 90 underwent hematopoietic stem cell transplantation (HSCT), 24 were chronically transfused, and 170 had never had any DMT. Hydroxyurea showed significant benefit on patients outcome as reflected by a lower mortality rate compared to transplanted individuals or people without DMT (0.14, 0.36, and 0.38 per 100 PY, respectively) and by higher Kaplan–Meier estimates of 15 year survival (99.4%) compared to HSCT (93.8%; P = 0.01) or no DMT groups (95.4%; P = 0.04). Conclusion SCD mortality in Belgium is low with no increase observed in young adults. Patients treated with hydroxyurea demonstrate a significant benefit in survival when compared to those without DMT or transplanted. Pediatr Blood Cancer © 2015 Wiley Periodicals, Inc.

ObjectivesTo compare the outcomes of sickle cell disease patients diagnosed through neonatal screening with those who were not.MethodsIn an observational multicenter study in Belgium, 167 screened and 93 unscreened sickle cell disease patients were analyzed for a total of 1116 and 958 patient-years of follow-up, respectively. Both groups were compared with propensity score analysis, with patients matched on three covariates (gender, genotype, and central Africa origin). Bonferroni correction was applied for all comparisons.ResultsKaplan–Meier estimates of survival without bacteremia were significantly higher in the screened group than the unscreened group (94.47%; [95% CI, 88.64–97.36%] versus 83.78% [95% CI, 72.27–90.42%]), p = 0.032. Non-significant differences between both groups were reported for survival without acute chest syndrome, acute anemia, cerebral complication, severe infection, and vaso-occlusive crisis. Significantly lower hospitalization rate and days per 100 patient-years were observed in the screened compared with the unscreened group (0.27 vs. 0.63 and 1.25 vs. 2.82, p = 0.0006 and ConclusionThese data confirm the benefit of a neonatal screening programme in reducing bacteremia and hospitalization.

Asparaginase is an essential component of combination chemotherapy for childhood acute lymphoblastic leukemia and non-Hodgkin lymphoma. The value of asparaginase was further addressed in a group of non-very high-risk patients by comparing prolonged (long-asparaginase) versus standard (short-asparaginase) native E. coli asparaginase treatment in a randomized part of the phase III 58951 trial of the European Organization for Research and Treatment of Cancer Children’s Leukemia Group. The main endpoint was disease-free survival. Overall, 1,552 patients were randomly assigned to long-asparaginase (775 patients) or short-asparaginase (777 patients). Patients with grade ≥2 allergy to native E. coli asparaginase were switched to equivalent doses of Erwinia or pegylated E. coli asparaginase. The 8-year disease-free survival rate (±standard error) was 87.0±1.3% in the long-asparaginase group and 84.4±1.4% in the short-asparaginase group (hazard ratio: 0.87; P=0.33) and the 8-year overall survival rate was 92.6±1.0% and 91.3±1.2% respectively (hazard ratio: 0.89; P=0.53). An exploratory analysis suggested that the impact of long-asparaginase was beneficial in the National Cancer Institute standard-risk group with regards to disease-free survival (hazard ratio: 0.70; P=0.057), but far less so with regards to overall survival (hazard ratio: 0.89). The incidences of grade 3–4 infection during consolidation (25.2% versus 14.4%) and late intensification (22.6% versus 15.9%) and the incidence of grade 2–4 allergy were higher in the long-asparaginase arm (30% versus 21%). Prolonged native E. coli asparaginase therapy in consolidation and late intensification for our non-very high-risk patients did not improve overall outcome but led to an increase in infections and allergy. This trial was registered at www.clinicaltrials.gov as #NCT00003728.

We describe here the case of a 13-month-old boy who acquired HIV infection postnatally through breastfeeding in a developed country in 2012. His mother had regular pregnancy follow-up and was found to be seronegative for HIV on 2 consecutive screening tests (during pregnancy and just after delivery). However, 1 year later, diagnosis of HIV infection arose in both of them after a pediatric emergency department visit for bronchitis when unexplained hepatosplenomegaly and inflammatory syndrome were noted. The negative maternal viral load found just after delivery confirmed that the mother’s seroconversion occurred postnatally, which allowed for active HIV transmission during lactation and lack of the efficient preventive measures that have implemented in Belgium for years. We discuss this uncommon but still existing mode of HIV transmission in industrialized countries and highlight the importance of implementing new targeted health education interventions in addition to constant clinicians’ awareness.

Objective Red cell exchange transfusion is frequently used in the management of patients with sickle cell disease (SCD) either electively or chronically to maintain hemoglobin S (HbS)

Viral infections are important causes of morbidity and mortality in patients after hematopoietic stem cell transplantation. The monitoring by PCR of Herpesviridae loads in blood samples has become a critical part of posttransplant follow-up, representing mounting costs for the laboratory. In this study, we assessed the clinical performance of the multiplex PCR DNA microarray Clart Entherpex kit for detection of cytomegalovirus (CMV), Epstein-Barr virus (EBV), and human herpesvirus 6 (HHV-6) as a screening test for virological follow-up. Two hundred fifty-five blood samples from 16 transplanted patients, prospectively tested by routine PCR assays, were analyzed by microarray. Routine PCR detected single or multiple viruses in 42% and 10% of the samples, respectively. Microarray detected single or multiple viruses in 34% and 18% of the samples, respectively. Microarray results correlated well with CMV and EBV detections by routine PCR (kappa tests = 0.79 and 0.78, respectively), whereas a weak correlation was observed with HHV-6 (0.43). HHV-7 was also detected in 48 samples by microarray. In conclusion, the microarray is a reliable screening assay for a posttransplant virological follow-up to detect CMV and EBV infections in blood. However, positive samples must be subsequently confirmed and viral loads must be quantified by PCR assays. Limitations were identified regarding HHV-6 detection. Although it is promising, is easy to use as a first-line test, and allows a reduction in the cost of analysis without undue delay in the reporting of the final quantitative result to the clinician, some characteristics of this microarray should be improved, particularly regarding quality control and the targeted virus panel, such that it could then be used as a routine test.

STUDY QUESTION Do the benefits of ovarian tissue cryopreservation outweigh the risks for patients seeking to preserve fertility before gonadotoxic treatment in various indications? SUMMARY ANSWER In >90% of the patients undergoing cryopreservation of ovarian tissue, oncological treatment was associated with a reduced ovarian reserve and in 30% of patients, premature ovarian failure (POF) occurred within 5 years. WHAT IS KNOWN ALREADY Ovarian tissue cryopreservation is an effective fertility preservation option, especially for pre-pubertal patients and patients who have a short time between diagnosis of a disease and gonadotoxic treatment. STUDY DESIGN, SETTING, DURATION This study retrospectively analysed ovarian function and fertility recovery rates, as well as ovarian tissue characteristics, of patients who underwent ovarian tissue cryopreservation at Erasme Hospital between 1999 and 2011. PARTICIPANTS/MATERIALS, SETTINGS, METHODS A total of 225 patients referred from 15 Belgian oncological units underwent cryopreservation of ovarian tissue before gonadotoxic therapy for malignant or benign diseases. There were 28 patients (12.4%) who died during follow-up due to recurrence of disease. One severe adverse event occurred during anaesthesia for ovarian tissue collection, leading to the death of the patient. Ovarian function and fertility outcomes were available for 114 patients including 13 girls who were pre-pubertal at the time of the procedure. Eight patients had undergone ovarian tissue transplantation in order to restore their fertility after remission of the disease. MAIN RESULTS AND THE ROLE OF CHANCE Breast cancer and haematological disease were the most frequent indications for ovarian tissue cryopreservation. Overall, 90% of post-pubertal patients were diagnosed with poor ovarian reserve (AMH 40 IU/ml). Breast cancer patients had a lower rate of POF than did post-pubertal patients with haematological diseases (11 versus 34.5%, respectively), despite the older age (mean 31 versus 23.5 years old, respectively) of the breast cancer patients. Ovarian function returned in 71 post-pubertal patients without the need for grafts of cryopreserved tissue. Spontaneous pregnancies were reported for 33 of them, leading to 34 live births. Among the 13 pre-pubertal patients who reached pubertal age during the follow-up, 10 had POF. Eight patients received cryopreserved ovarian grafts to reverse POF and three of them have already become pregnant. LIMITATIONS, REASONS FOR CAUTION This study is a retrospective analysis. The cohort was not compared with a control group of patients who did not undergo the procedure. WIDER IMPLICATIONS OF THE FINDINGS After careful evaluation of the surgical risks, ovarian tissue cryopreservation can be proposed as an efficient option to preserve the fertility of children and young adults facing gonadotoxic therapies. However, alternative procedures such as oocyte or embryo cryopreservation should be considered as first options especially for older patients or if there is high risk of neoplastic cells within the ovaries. STUDY FUNDING/COMPETING INTEREST This study was supported by the Tele vie, FNRS-FRSM and Fondation Belge contre le cancer. There are no competing interests to report. © 2014 The Author.

Dexamethasone could be more effective than prednisolone at similar anti-inflammatory doses in the treatment of childhood acute lymphoblastic leukemia. In order to check if this "superiority" of dexamethasone might be dose-dependent, we conducted a randomized phase III trial comparing dexamethasone (6 mg/m(2)/day) to prednisolone (60 mg/m(2)/day) in induction therapy. All newly diagnosed children and adolescents with acute lymphoblastic leukemia in the 58951 EORTC trial were randomized on prephase day 1 or day 8. The main endpoint was event-free survival; secondary endpoints were overall survival and toxicity. A total of 1947 patients with acute lymphoblastic leukemia were randomized. At a median follow-up of 6.9 years, the 8-year event-free survival rate was 81.5% in the dexamethasone arm and 81.2% in the prednisolone arm; the 8-year overall survival rates were 87.2% and 89.0% respectively. The 8-year incidences of isolated or combined central nervous system relapse were 2.9% and 4.5% in the dexamethasone and prednisolone arms, respectively. The incidence of grade 3-4 toxicities during induction and the frequency of osteonecrosis were similar in the two arms. In conclusion, dexamethasone and prednisolone, used respectively at the doses of 6 and 60 mg/m(2)/day during induction, were equally effective and had a similar toxicity profile. Dexamethasone decreased the 8-year central nervous system relapse incidence by 1.6%. This trial was registered at www.clinicaltrials.gov as #NCT00003728.

Despite improvements in medical management, sickle cell disease (SCD) remains associated with severe morbidity and decreased survival. Allogeneic haematopoietic stem cell transplantation (HSCT) remains the only curative approach. We report the outcome of 50 consecutive children with severe SCD that received HSCT in our unit between November 1988 and April 2013. The stem cell source was bone marrow (n = 39), cord blood (n = 3), bone marrow and cord blood (n = 7) and peripheral blood stem cells (n = 1). All patients had ≥1 severe manifestation: 37 presented with recurrent vaso-occlusive crises/acute chest syndrome, 27 cerebral vasculopathy and 1 nephropathy. The conditioning regimen consisted of busulfan + cyclophosphamide (BuCy) before November 1991 and BuCy + rabbit antithymocyte globulin after that date. Since 1995, all patients have been treated with hydroxycarbamide (HC) prior to transplantation for a median duration of 2·7 years. Median age at transplantation and median follow-up was 8·3 and 7·7 years, respectively. Acute graft-versus-host disease (GVHD) and chronic GVHD were observed in 11 and 10 patients, respectively. An excellent outcome was achieved, with 8-year overall survival and event-free survival (EFS) rates of 94·1% and 85·6%, respectively. Since HC introduction, no graft failure occurred and EFS reached 97·4%. Prior treatment with HC may have contributed to successful engraftment.

Newborn sreening (NS) for sickle cell disease (SCD) is effective in reducing early mortality and morbidity through education, prevention of infections and strategies to prevent stroke in children at risk of cerebral vasculopathy. Universal NS was implemented in all Brussels maternity wards since 2000. All identified children with SCD benefited from comprehensive medical care in dedicated centers. This retrospective study included all children with SCD diagnosed through NS and born between January 2000 and December 2005 (Group 1) and between January 2010 and December 2015 (Group 2) followed at Hôpital Universitaire des Enfants Reine Fabiola (Brussels, Belgium). Only patients whose parents consented to be recorded in the Belgian SCD database were eligible for this study. The aim of our study was to compare the outcome of 2 NS cohorts born at 10 years of interval. Demographic data, baseline hematological values and clinical events, occurrence of cerebral vasculopathy and prescription of disease-modifying treatments during the first 5 years of life were compared between both groups. Data were collected until March 1, 2019. 59 patients were identified for this study (35 in Group 1 and 24 in Group 2). Their characteristics are detailed in Table 1. Two patients in Group 2 did not completed the full 5-year evaluation period. Among these 59 patients, 77.9% patients developed at least one SCD clinical event before the age of 5. The number of patients who developed a specific clinical event as well as their age at this first event was the same between the 2 groups (Table 2). The hospitalization number and hospitalization days were not statistically different in the 2 groups (5 vs 4 hospitalizations during 5 years and 19 vs 17 days of hospitalization between Groups 1 and 2 respectively). 3 patients presented an overt stroke (1 in Group 1 and 2 in Group 2) with a global incidence of 1.02 stroke per 100 patient-years. No death was reported in both groups. The proportion of patients with abnormal transcranial doppler velocities decreased slightly in Group 2 (14.3% vs 8.3%, P=0.69) with more conditional velocities (5.7% vs 20.8%, P=0.10) but it was not statistically significant. 60% of patients in Group 1 were treated with hydroxyurea (HU) compared to 75% in Group 2 (P=0.27). HU was introduced at a median age of 2.5 (0.9-4.8) and 2.3 (0.8-4.8) in Groups 1 and 2 respectively (P=0.79). One patient from each group underwent an hematopoietic stem cell transplantation at 4.9 and 3.5 years. Hematological values were not different in the 2 groups excepted for platelets count, which were significantly lower in Group 2 (421 x 10³/µl vs 331 x 10³/µl, P=0.03). Moreover in patients under HU, platelet and reticulocytes count were statistically lower and HbF higher in Group 2 compared to Group 1 (Table 3). Nearly 80% of patients presented a clinical event before the age of 5. This is comparable to what is described in the literature. The Kaplan-Meier survival curves were not statistically different in both groups for the occurrence of a first dactylitis (P=0.52), a first vaso-occlusive crisis (P=0.22) and acute chest syndrome (P=0.37). No more difference was observed for acute anemia (P=0.43), severe infection (P=0.35) or patients under HU (P=0.40). Even if the number of patients on hydroxyurea is not statistically higher in Group 2, a better exposure to hydroxyurea is attested by the significant changes in some biological parameters. The limits of this study are the small size of our single center cohort and the exclusion of patients not recorded in the Belgian Registry because of lack of parental consent. This last point might create a bias by selecting patients whose parents are more prone to participate actively in the comprehensive care program. This periodic evaluation is essential to ensure the quality of care of patients and to measure possible changes in the management. Comprehensive care developed in our tertiary center had been already effective since 2000. Physicians not only tend to prescribe more hydroxyurea in young symptomatic patients, but also routinely adjust the dose to reach the maximal tolerated dose. Moreover adherence to treatment has been achieved through continuous education. Disclosures No relevant conflicts of interest to declare.

Introduction and Aim Although cytogenetics and response-guided therapy have considerably improved prognostication of pediatric AML (pedAML) patients, still 30-40% of the good responders relapse. Further delineation of the transcriptome of AML subpopulations, e.g. leukemic stem cells (LSCs), might result in a better understanding of pedAML biology and provide novel biomarkers for diagnostics, risk stratification, follow-up and targeted therapy. Methods Fluorescence-activated cell sorting (FACS) was used to isolate CD34+CD38- and CD34+CD38+ cells from pedAML patients/healthy controls (cord blood (CB), normal bone marrow (NBM)), defined as LSC/hematopoietic stem cell (HSC) and leukemic blast (L-blast)/control blast (C-blast), respectively. Sorting multiple phenotypes, both BM and blood, yielded 42 LSC and 35 L-blast fractions. Gene expression profiles (GEP) of LSCs and L-blasts were identified by a Cancer vs Normal (CvN) approach, whereas paired analysis of LSC vs L-blast aimed to identify LSC-specific aberrations. Micro-array analysis (4 pedAML, 3 CB) was followed by targeted quantitative PCR (qPCR) validation of the highest differentially expressed genes (DEGs) in LSC (n=52), L-blast (n=42) and between LSC and L-blast (n=15) (25 pedAML, 11 CB/9 NBM). DEGs were functionally analysed by protein association (STRING) and by gene set enrichment analysis (GSEA-Cytoscape). An overview of the workflow is shown in Fig. 1A. Results LSC vs HSC micro-array analysis revealed 83 up- and 212 downregulated targets (Fig. 1B). qPCR confirmed 8 and 11 of the 52 tested targets to be highly significantly up- and downregulated, respectively, in LSC (n=42) compared to HSC (n=20) (P L-blasts showed 157 and 332 up- and downregulated DEGs (Fig. 1C), and 8/42 were confirmed as significantly upregulated by qPCR (L-blast=35 vs C-blast=19, P Gene sets enriched in LSCs vs L-blasts addressed inflammatory responses, adipogenesis, TNF signaling and response. Pathway analysis showed repression of cell cycle genes, consistent with LSC quiescence. qPCR validation of 15 out of the 117 upregulated targets (Fig. 1D), of which 5/15 had a neural link (PCDHB2, GPRIN3, SLC22A23, CDR1, RPGRIP1L), did not confirm significant dysregulated expression (P>.05). Interestingly, the set of DEGs between LSCs and L-blasts shared only few genes with those differentially expressed between HSC and C-blast (28/306; 4 up- and 24 downregulated). This low intersection (7.7%) is in strong contrast to the previously reported 34% in adult AML (Gal et al. 2006). Moreover, none of those genes were detected in adult AML (except for CD38 downregulation). Remarkably, 3/4 mutual upregulated genes (IGF2, GPRIN3, PROS1, CYTH4) are involved in neural crossroads and have no relation to stemness nor AML. Conclusion Combining FACS with CvN transcriptomic profiling, followed by qPCR validation, identified novel DEGs in pedAML subpopulations. The majority of the most significant upregulated targets in LSCs (n=8) and L-blasts (n=8) showed no previous link to pedAML. Identification of 11 novel downregulated targets, often described as TSGs in solid tumors, warrants further studies whether hypomethylating therapy could result into LSC eradication in pedAML. LSCs reflected low cell cycle activity and elevated inflammatory response, hypoxia, metabolic dysregulation and signaling compared to HSC. GEP of LSCs vs L-blasts revealed a distinct molecular landscape compared to adult AML, and suggested a possible link between distortion of neural and hematopoietic systems in leukemogenesis. Figure Disclosures No relevant conflicts of interest to declare.

Background: Hematopoietic stem cell transplantation (HSCT), the only available curative therapy for sickle cell disease (SCD), remains hampered by the lack of histocompatible stem cell donors. Most patients will not have a suitable human leukocyte antigen(HLA) matched sibling donor. In addition, SCD affects ethnic groups that are underrepresented in stem cell donor registries worldwide. Objective: to assess the probability of having a potential allelic HLA matched unrelated donor(MUD) for HLA-A,B and DRB1 loci (6/6) in international donor registries for patients with SCD. Methods: 185 patients with SCD were included, 116 from Brazil, of whom 23 underwent HSCT, and 69 patients who underwent HSCT in centers reporting to the European Society for Blood and Marrow Transplantation (EBMT). All patients had HLA typing available at intermediate or high resolution. For intermediate resolution, using the National Marrow Donor Program (NMDP) code, we assigned alleles based on allele frequencies.We performed HLA haplotype estimation using the HaploStats website, which describes HLA haplotype frequency from the NMDP registry for the following ethnic groups: Caucasian, African-American, Asian, Hispanic and Native American. Because Hispanic is not a primary ethnicity, we did not consider this group in our analyses. Based on haplotype frequency of each ethnic group, we defined the most likely ethnicity for each estimated haplotype; those with frequency >1:1000 in all ethnic groups were named common. Unrelated donor search was done using the World Marrow Donor Association (WMDA) algorithm, which is based on haplotype matching. A potential allelic donor was defined as a full match high resolution 6/6 donor. Because it is described that testing at least 5 potential allelic donors simultaneously increases the chances of having a real donor, we assessed the probability of finding at least 1 and at least 5 potential allelic donors. Patients who received HSCT from MUD were excluded from donor searches (n=10).Comparisons of probabilities of having potential allelic donors between Brazilian and EBMT cohorts were performed by chi-square. Results: In the Brazilian cohort, from 181 HLA haplotypes, 45% were classified as African-American, 18% common, 12% Caucasian, 9% Amerindian and 16% could not be classified. In the EBMT cohort, from 116 HLA haplotypes, 70% were classified as African-American, 8% common, 6% Caucasian, 3% Amerindian and 13% were not classified. Although Brazilians showed greater genetic admixture, chances of finding at least one potential allelic MUD were 47% in both groups (p-value not significant) and chances of having at least 5 potential allelic MUD were 24% for Brazilians and 15% for EBMT (p-value not significant). Overall, most potential allelic MUD were found in the NMDP registry, followed by the Brazilian registry (REDOME) and by the German registry (ZKMD); for the Brazilian cohort, most potential allelic MUD were found in REDOME. Discussion: Migration from Africa to Brazil started at the colonial period, and interethnic admixture have been occurring since then, explaining the higher diversity observed in the Brazilian cohort. Despite differences in ethnic composition, chances of having at least one potential allelic MUD are identical, probably because carrying at least one African or Amerindian haplotype decreases the chances of a full HLA matching. Although we demonstrated higher probabilities of finding a potential allelic MUD in SCD than previous studies, the chances are still low, therefore further strategies are required to increase donor representativeness for SCD. In this setting, alternative sources, such as haploidentical HSCT and cord blood, should be considered. Also, our study might help to predict the probabilities of finding a MUD for patients with SCD. This is important because given that HSCT in SCD has better results if performed at earlier age, knowing which patients are less likely to find a MUD might influence therapy management. Disclosures No relevant conflicts of interest to declare.