JAK inhibitor treatment for inborn errors of JAK/STAT signaling: An ESID/EBMT-IEWP retrospective study.

BACKGROUND: Inborn errors of immunity (IEI) with dysregulated JAK/STAT signaling present with variable manifestations of immune dysregulation and infections. Hematopoietic stem cell transplantation (HSCT) is potentially curative, but initially reported outcomes were poor. JAK inhibitors (JAKi) offer a targeted treatment option that may be an alternative or bridge to HSCT. However, data on their current use, treatment efficacy and adverse events are limited. OBJECTIVE: We evaluated the current off-label JAKi treatment experience for JAK/STAT inborn errors of immunity (IEI) among European Society for Immunodeficiencies (ESID)/European Society for Blood and Marrow Transplantation (EBMT) Inborn Errors Working Party (IEWP) centers. METHODS: We conducted a multicenter retrospective study on patients with a genetic disorder of hyperactive JAK/STAT signaling who received JAKi treatment for at least 3 months. RESULTS: Sixty-nine patients (72% children) were evaluated (45 STAT1 gain of function [GOF], 21 STAT3-GOF, 1 STAT5B-GOF, 1 suppressor of cytokine signaling 1 [aka SOCS1] loss of function, 1 JAK1-GOF). Ruxolitinib was the predominantly prescribed JAKi (80%). Overall, treatment resulted in improvement (partial or complete remission) of clinical symptoms in 87% of STAT1-GOF and in 90% of STAT3-GOF patients. We documented highly heterogeneous dosing and monitoring regimens. The response rate and time to response varied across different diseases and manifestations. Adverse events including infection and weight gain were frequent (38% of patients) but were mild (grade I-II) and transient in most patients. At last follow-up, 52 (74%) of 69 patients were still receiving JAKi treatment, and 11 patients eventually underwent HSCT after receipt of previous JAKi bridging therapy, with 91% overall survival. CONCLUSIONS: Our study suggests that JAKi may be highly effective to treat symptomatic JAK/STAT IEI patients. Prospective studies to define optimal JAKi dosing for the variable clinical presentations and age ranges should be pursued.

Allergies, genetic polymorphisms of Th2 interleukins, and childhood acute lymphoblastic leukemia: The ESTELLE study.

CONTEXT: A negative association between a history of allergy and childhood acute lymphoblastic leukemia (ALL) has been reported in previous studies, but remains debated. This work aimed to investigate this association accounting for genetic polymorphisms of the Th2 pathway cytokines (IL4, IL10, IL13, and IL4R). METHODS: Analyses were based on the French case-control study ESTELLE (2010-2011). The complete sample included 629 ALL cases and 1421 population-based controls frequency-matched on age and gender. The child's medical history was collected through standardized maternal interview. Biological samples were collected, and genotyping data were available for 411 cases and 704 controls of European origin. Odds ratios (OR) were estimated using unconditional regression models adjusted for potential confounders. RESULTS: In the complete sample, a significant inverse association was observed between ALL and reported history of allergic rhinitis or sinusitis (OR = 0.65 [0.42-0.98]; P = 0.04), but there was no obvious association with allergies overall. There was an interaction between genetic polymorphisms in IL4 and IL4R (Pinteraction = 0.003), as well as a gene-environment interaction between IL4R-rs1801275 and a reported history of asthma (IOR = 0.23; Pint  = 0.008) and eczema (IOR = 0.47; Pint  = 0.06). We observed no interaction with the candidate polymorphisms in IL4 and IL13. CONCLUSION: These results suggest that the association between allergic symptoms and childhood ALL could be modified by IL4R-rs1801275, and that this variant could also interact with a functional variant in IL4 gene. Although they warrant confirmation, these results could help understand the pathological mechanisms under the reported inverse association between allergy and childhood ALL.

Mutations in the SRP54 gene cause severe congenital neutropenia as well as Shwachman-Diamond-like syndrome.

Congenital neutropenias (CNs) are rare heterogeneous genetic disorders, with about 25% of patients without known genetic defects. Using whole-exome sequencing, we identified a heterozygous mutation in the SRP54 gene, encoding the signal recognition particle (SRP) 54 GTPase protein, in 3 sporadic cases and 1 autosomal dominant family. We subsequently sequenced the SRP54 gene in 66 probands from the French CN registry. In total, we identified 23 mutated cases (16 sporadic, 7 familial) with 7 distinct germ line SRP54 mutations including a recurrent in-frame deletion (Thr117del) in 14 cases. In nearly all patients, neutropenia was chronic and profound with promyelocytic maturation arrest, occurring within the first months of life, and required long-term granulocyte colony-stimulating factor therapy with a poor response. Neutropenia was sometimes associated with a severe neurodevelopmental delay (n = 5) and/or an exocrine pancreatic insufficiency requiring enzyme supplementation (n = 3). The SRP54 protein is a key component of the ribonucleoprotein complex that mediates the co-translational targeting of secretory and membrane proteins to the endoplasmic reticulum (ER). We showed that SRP54 was specifically upregulated during the in vitro granulocytic differentiation, and that SRP54 mutations or knockdown led to a drastically reduced proliferation of granulocytic cells associated with an enhanced P53-dependent apoptosis. Bone marrow examination of SRP54-mutated patients revealed a major dysgranulopoiesis and features of cellular ER stress and autophagy that were confirmed using SRP54-mutated primary cells and SRP54 knockdown cells. In conclusion, we characterized a pathological pathway, which represents the second most common cause of CN with maturation arrest in the French CN registry.

Management of childhood aplastic anemia following liver transplantation for nonviral hepatitis: A French survey.

BACKGROUND: Hepatitis-associated aplastic anemia (AA) is a rare syndrome combining acute hepatitis of variable severity and AA. Hepatitis may be severe enough to require urgent liver transplantation (LT). Herein, we describe clinical presentation and management of a cohort of pediatric patients diagnosed with AA after undergoing LT for nonviral hepatitis. METHODS: To describe this rare clinical situation, we performed a national survey and identified nine children treated for AA following LT during the last 10 years in France. RESULTS: All patients were treated first for hepatic failure with urgent LT. AA was diagnosed with a median delay of 34 days [21-200] from the diagnosis of hepatitis. Seven children were treated with antithymocyte globulin/cyclosporine, one with CSA alone and one received bone marrow transplantation. At the last visit (median follow-up: 4 years), outcomes were excellent: all patients were alive and in hematological remission (complete remission: 7; partial remission: 2). Immunosuppressive therapy was pursued in all patients due to the liver transplant. No unusual toxicities were reported. CONCLUSION: AA after LT is considered a therapeutic challenge. Nevertheless, hematological outcome is good using a standard immunosuppressive approach.

An effective modestly intensive re-induction regimen with bortezomib in relapsed or refractory paediatric acute lymphoblastic leukaemia.

This trial explored the efficacy of re-induction chemotherapy including bortezomib in paediatric relapsed/refractory acute lymphoblastic leukaemia. Patients were randomized 1:1 to bortezomib (1.3 mg/m2 /dose) administered early or late to a dexamethasone and vincristine backbone. Both groups did not differ regarding peripheral blast count on day 8, the primary endpoint. After cycle 1, 8 of 25 (32%) patients achieved complete remission with incomplete blood count recovery, 7 (28%) a partial remission and 10 had treatment failure. Most common grade 3-4 toxicities were febrile neutropenia (31%) and pain (17%). Bortezomib was safely combined with vincristine. Bortezomib rarely penetrated the cerebrospinal fluid.

Detection of a new heterozygous germline ETV6 mutation in a case with hyperdiploid acute lymphoblastic leukemia.

ETV6 is a target of recurrent aberrations in sporadic and familial acute lymphoblastic leukemia (ALL). Here, we report on a new pedigree with a germline ETV6 mutation in which the index patient and his father developed high hyperdiploid (HeH) ALL and polycythemia vera at age 13 and 51, respectively. The index patient achieved durable complete remission without transplantation but had persistent moderate thrombocytopenia without bleeding tendency. To determine the prevalence of ETV6 alterations in HeH-ALL, we screened 81 unrelated subjects with HeH-ALL by single nucleotide polymorphism array and high-throughput sequencing for the ETV6 gene. Overall, ETV6 microdeletions and mutations were identified in 9% of cases, all of which were somatic and considered as secondary events. Apart from the index patient, no germline ETV6 aberration was identified. Finally, we reviewed the literature for ETV6 germline aberrations and predispositions to ALL.

Benefits of rituximab as a second-line treatment for autoimmune haemolytic anaemia in children: a prospective French cohort study.

Childhood autoimmune haemolytic anaemia (AIHA) requires second-line immunosuppressive therapy in 30-50% of cases. It appears that rituximab is indicated in such circumstances. This prospective national study reports the practice, efficacy and tolerance of rituximab in children with isolated AIHA and AIHA in the setting of Evans syndrome (ES). Sixty-one children were given rituximab between 2000 and 2014. The median interval from diagnosis to rituximab was 9·9 [interquartile range (IQR) 1·6-28·5] months. Forty-six patients responded (75%) and the 6-year relapse-free survival (RFS) was 48%. Twenty patients relapsed at a median interval of 10·8 (IQR 3·9-18·7) months, rituximab allowed steroid withdrawal in 44/61 (72%) of children. In isolated AIHA, complete response and 6-year RFS were significantly higher than in ES (P < 0·05). Ten out of 61 patients were infants, seven of who responded with a 6-year RFS of 71%. Among patients without immunoglobulin substitution before rituximab, 4 are still receiving substitutions. Five patients died, including one potentially attributable to rituximab. This large observational series of childhood AIHA established the rituximab benefit-risk ratio, allowing steroid withdrawal, with 37% of long-term responders, mainly in isolated AIHA. All subgroups of patients drew benefit. Our long-term results indicate the baseline to be challenged by new treatment approaches.

A Phase I Study of Clofarabine With Multiagent Chemotherapy in Childhood High Risk Relapse of Acute Lymphoblastic Leukemia (VANDEVOL Study of the French SFCE Acute Leukemia Committee).

BACKGROUND: Current outcome of very early relapse of acute lymphoblastic leukemia (ALL) in children remains poor. As a single agent, clofarabine provided a response rate of 26% in childhood ALL second relapse and, in combination with cyclophosphamide and etoposide, a 44% complete remission and complete remission without platelet recovery (CR+CRp) rate. Further multi-drug combinations need to be investigated. We used the VANDA regimen as a template, cytarabine being replaced by clofarabine. PATIENTS AND METHODS: A phase I study combining escalating doses of clofarabine (25% increments from 20 to 40 mg/m(2)/d) with fixed doses of mitoxantrone, etoposide, asparaginase, and dexamethasone was undertaken in children presenting with very early or second or post-transplant ALL relapse. RESULTS: Twenty patients were enrolled, 19 were evaluable. Four patients had previously been allografted. Dose-limiting toxicity (DLT) appeared at dose level 3 (32 mg/m(2)), one out of six patients experienced a liver DLT. At dose level 4 (40 mg/m(2)), four DLT occurred (two fungal infection and two liver DLT). The maximum tolerated dose (MTD) of clofarabine was thus determined to be 32 mg/m(2). There was no toxic death. Eleven (57.9%) patients achieved a CR. Six patients proceeded to allogeneic stem cell transplantation. CONCLUSION: Clofarabine MTD was 32 mg/m(2)/d in this combination which appeared feasible and effective in this population.

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.

Hyperdiploidy with 58-66 chromosomes in childhood B-acute lymphoblastic leukemia is highly curable: 58951 CLG-EORTC results.

The aim of our study was to analyze the factors contributing to heterogeneity of prognosis in patients with hyperdiploidy>50 chromosomes (HD>50), a group of B-cell precursor acute lymphoblastic leukemia with favorable outcome. The 541 HD>50 patients registered prospectively in the 58951 European Organisation for Research and Treatment of Cancer (EORTC) Children's Leukemia Group (CLG) trial, identified by karyotype (446 patients) and by DNA index (DI) (490 patients), had a 6-year event-free survival (EFS) of 89.0% (standard error [SE] = 1.5%) and a 6-year overall survival (OS) of 95.9% (SE = 0.9%). The strongest prognostic factor was the modal number of chromosomes (MNC): the 6-year EFS of 51-53, 54-57, and 58-66 MNC groups were 80%, 89%, and 99%, respectively (P < .0001). Ploidy assessed by DI was also a favorable factor: the higher the DI, the better the outcome. The 6-year EFS of the 3 subgroups of DI < 1.16/≥1.16-<1.24/≥1.24 were 83%, 90%, and 95%, respectively (P = .009). All usual combinations of trisomies (chromosomes 4, 10, 17, 18) were significant favorable factors but had lower EFS when MNC was lower than 58. In multivariate analysis, MNC remained the strongest factor. Consequently, the best indicator for excellent outcome was ploidy assessed by karyotype because patients with 58-66 chromosomes stood every chance of being cured (OS of 100% at 6-year follow-up) with less-intensive therapy. This trial was registered at www.clinicaltrials.gov as #NCT00003728. Registered: http://www.eortc.org/, http://clinicaltrials.gov/show/NCT00003728.

Detection of dicentric chromosome (9;20) in paediatric B-cell acute lymphoblastic leukaemia: prognostic significance.

The dicentric chromosome (9;20) (dic(9;20)) is described in 2 % of childhood B-acute lymphoblastic leukaemia. Fluorescence in situ hybridization (FISH) is the most reliable method to identify dic(9;20) when compared with conventional cytogenetics. To define the prognostic importance of dic(9;20), we evaluated treatment response and patient survival. This was a retrospective study in three French university centres. Patients' clinical and laboratory characteristics and treatment response are described. Nine children with dic(9;20) have been identified since 1995. All patients had at least one poor prognostic feature either among the clinical features, the initial laboratory results or in the initial treatment response: central nervous system involvement (2/9), high median leucocyte count (≥50 G/L) (8/9) and poor response to prednisone (2/9). All patients were in complete cytological remission after induction therapy but only three had a good molecular response with minimal residual disease (MRD) <10(-3). Five out of nine patients relapsed and two died, 4 and 12 months after diagnosis, respectively. The event-free survival rate in this population was 44 % (95 % confidence interval (CI) = 0.09-0.79) and overall survival 78 % (95 % CI = 0.51-1.05). In this population, dic(9;20) is associated with a relatively poor prognosis. Patients showing dic(9;20), whether this cytogenetic abnormality is associated with other poor prognostic factors or not, should be identified at the outset in order to be offered a more intensive treatment protocol.

In vitro analysis of overall particulate contamination exposure during multidrug IV therapy: impact of infusion sets.

BACKGROUND: Drug incompatibilities, recognizable through precipitate, may have clinical consequences for patients, especially during multidrug IV therapies, where vancomycin and piperacillin are present. Drug concentration and infusion set influence the overall particulate contamination of pediatric infusion protocols. The use of multi-lumen infusion sets could prevent such incompatibilities. Our goal was to define and assess a new way to infuse these drugs during leukemia treatment in children. PROCEDURES: This in vitro study focused on a pediatric multidrug protocol for patients diagnosed with lymphoblastic leukemia and receiving allogeneic transplantation. Different vancomycin concentrations were tested to infuse incompatible drugs simultaneously without any particle formation (optimized multidrug protocol). A dynamic particle count test was used over 24 hr to evaluate the overall particulate contamination of our standard and optimized multidrug protocols, using both a standard and a multi-lumen infusion set. RESULTS: No visible particles were detected on a decreased vancomycin concentration compared to the standard dose. For the optimized multidrug protocol, the use of a multi-lumen infusion set reduced overall particulate contamination by 68%, compared to the standard infusion set (P = 0.002). Large-sized particles were significantly reduced when using the multi-lumen infusion set approximately 60% (P = 0.027) and 90% (P = 0.009) for particle sizes ≥10 µm and 25 µm, respectively. CONCLUSIONS: This study demonstrates that a large number of particles can be administered during parenteral multidrug infusion. The choice of drug concentration and/or the type of infusion set may reduce this. Further studies are required to evaluate adverse clinical effects.

Maternal reproductive history, fertility treatments and folic acid supplementation in the risk of childhood acute leukemia: the ESTELLE study.

PURPOSE: To investigate the potential involvement of fertility treatments and other conditions of becoming pregnant (infertility, getting pregnant on birth control, maternal history of fetal loss) and folic acid supplements in the etiology of childhood leukemia (CL). METHODS: The ESTELLE study included 747 cases of CL [636 cases of acute lymphoblastic leukemia (ALL) and 100 of acute myeloblastic leukemia (AML)] diagnosed in France in 2010-2011 and 1,421 population controls frequency-matched with the cases on age and gender. Data were obtained from structured telephone questionnaires administered to mothers. The odds ratios (OR) and their 95% confidence intervals were estimated using unconditional regression models adjusted for potential confounders. RESULTS: CL was not associated with difficulty in becoming pregnant [OR 0.9 (0.7-1.2)], in vitro fertilisation [OR 0.6 (0.3-1.5)] or the use of any fertility treatment [OR 0.8 (0.5-1.1)] for the index pregnancy. CL was not significantly associated with becoming pregnant on contraception [OR 1.2 (0.8-1.8)], but a positive association was observed for third generation oral contraception [OR 4.3 (1.2-16.2)]; however, the result is based on small numbers. Folic acid supplementation during pregnancy was not associated with CL, but an inverse borderline association was observed for supplementation initiated in the 3 months preceding pregnancy [OR 0.7 (0.5-1.0)]. In addition, maternal histories of stillbirth and miscarriage were associated with ALL [OR 2.6 (1.1-5.9)] and AML [OR 1.8 (1.1-2.8)], respectively. CONCLUSIONS: The findings do not suggest that infertility and fertility treatments are risk factors for CL. They suggest that maternal histories of stillbirth and miscarriage may be more frequent among mothers of CL cases and that folic acid supplementation during preconception may reduce the risk of CL.

Unexpected overestimation of methotrexate plasma concentrations: analysis of a single center pediatric population.

BACKGROUND: At this center, therapeutic drug monitoring of methotrexate (MTX) used to be performed by fluorescence polarization immunoassay (FPIA). We observed an increasing number of unusual high MTX concentrations at 48 and 72 hours during a couple of years. This study aimed to identify the causes of this variation. METHODS: A retrospective analysis was conducted on 272 patients hospitalized between January 2008 and October 2012. The whole MTX use system was analyzed using Ishikawa's method. The proportion of MTX concentrations ≤0.2 µmole/L at 48 (P48h) and 72 hours (P72h) was recorded and compared between both FPIA and EMITSiemens assays. A χ or a Fisher exact test was used (α = 0.05). RESULTS: Because of an announced withdrawal of the FPIA reagent, the method was switched in 2009 to an immunoenzymatic technique (EMITSiemens). Both P48h and P72h dropped significantly after 2009 (P48h: 45% versus 5% and P72h: 91% versus 47%; P < 0.0001). The replacement of the EMITSiemens reagent by the EMITARK Diagnostics reagent in 2012 led to an increase in both P48h and P72h. No significant difference was found in the proportions of MTX ≤0.2 µmole/L concentrations between FPIA and EMITARK Diagnostics at 48 (45% and 40%; P = 0.556) and 72 hours (91% and 100%; P = 0.231). Both internal and external quality control assessments gave regular satisfactory results during the study period. Furthermore, the interassay comparisons that were performed with internal quality controls and spiked serum samples showed similar results at the time of both shifts. The other changes observed in the MTX circuit were not associated with MTX concentration variations. CONCLUSIONS: The overestimation of the plasma concentration of MTX was concluded to be because of the assay reagent. A further study is consequently necessary to assess the impact of this analytical pitfall on the patients' survival.

Head and neck presentations of B-NHL and B-AL in children/adolescents: experience of the LMB89 study.

PURPOSE: Describe the epidemiology, clinical profiles and outcomes associated with head and neck (H&N) involvement in children/adolescents with B-cell non-Hodgkin lymphoma (B-NHL). METHODS: Analysis of children/adolescents with H&N B-NHL prospectively enrolled in the SFOP LMB-89 trial (July 1989-June 1996). RESULTS: One hundred and twelve of 561 patients (20%) had H&N involvement. The mean age of the patients was 8.4 years. Murphy staging differed between the H&N patients and the others (P < 0.0001): 9% versus 5% of the patients presented with stage I disease, 36% versus 11% presented with stage II disease, 12% versus 59% presented with stage III disease, 17% versus 10% with stage IV disease and 27% versus 16% with B-AL. Twenty-nine H&N patients (26%) had CNS involvement at diagnosis versus 8.5% in the group without H&N involvement (P < 0.0001). Patients were treated according to the LMB89 protocol: 3 H&N patients were allocated to group A, 70 to group B and 39 to group C. Ninety-seven percent of H&N patients achieved CR and event-free and overall survival at 4 years was 95.5% (5 deaths in patients with CNS disease). On multivariate analysis, EFS was significantly better in H&N patients than in non-H&N patients (P = 0.021), but not OS (P = 0.11). CONCLUSION: The H&N site is the second most common location for B-NHL at diagnosis and is more frequently associated with disseminated disease and CNS involvement than other sites. However, outcomes are no worse for these patients than for the rest of the population.

Childhood acute leukemia, maternal beverage intake during pregnancy, and metabolic polymorphisms.

PURPOSE: This study aimed to analyze the associations between childhood acute leukemia (AL) and maternal caffeinated beverage consumption during pregnancy, and to explore interactions between caffeinated and alcoholic beverage consumption and polymorphisms of enzymes involved in caffeine and ethanol metabolisms. METHODS: The data were generated by the French ESCALE study, which included 764 AL cases and 1,681 controls in 2003-2004. The case and control mothers were interviewed on their consumption habits during pregnancy using a standardized questionnaire. Genotypes of the candidate alleles (NAT2*5 rs1801280, ADH1C*2 rs698 and rs1693482, CYP2E1*5 rs2031920 and rs3813867) were obtained using high-throughput genotyping and imputation data for 493 AL cases and 549 controls with at least two grandparents born in Europe. RESULTS: Maternal regular coffee consumption during pregnancy was associated with childhood AL (OR = 1.2 [1.0-1.5], p = 0.02); the odds ratios increased linearly with daily intake (p for trend <0.001; >2 cups per day vs. no or less than 1 cup per week: AL: OR = 1.6 [1.2-2.1], lymphoblastic AL: OR = 1.5 [1.1-2.0], myeloblastic AL: OR = 2.4 [1.3-4.3]). The association was slightly more marked for children born to non-smoking mothers. Lymphoblastic AL was also associated with cola soda drinking (OR = 1.3 [1.0-1.5], p = 0.02). No significant gene-environment interactions with coffee, tea, cola soda, or alcohol drinking were observed. CONCLUSION: This study provides additional evidence that maternal coffee consumption during pregnancy may be associated with childhood AL. Coffee consumption is a prevalent habit and its potential involvement in childhood AL needs to be considered further.