The prognostic value of IKZF1plus in B-cell progenitor acute lymphoblastic leukemia: Results from the EORTC 58951 trial.

BACKGROUND: IKZF1 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 IKZF1plus , had the worst outcome. PROCEDURE: Between 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 IKZF1plus . RESULTS: Among 1200 patients included in the analysis, 1039 (87%) had no IKZF1 deletion (IKZF1WT ), 87 (7%) had an IKZF1 deletion but not IKZF1plus (IKZF1del ) and 74 (6%) had IKZF1plus . In the unadjusted analysis, both patients with IKZF1del (hazard ratio [HR] = 2.10, 95% confidence interval [CI]: 1.34-3.31) and IKZF1plus (HR = 3.07, 95% CI: 2.01-4.67) had a shorter event-free survival compared with IKZF1WT . However, although the IKZF1plus status was associated with patients' characteristics indicating poor prognosis, the difference between IKZF1plus and IKZF1del 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. CONCLUSIONS: In patients with BCP-ALL from the EORTC 58951 trial, the improvement of the prognostic importance of IKZF1 by considering IKZF1plus was not statistically significant.

Symptomatic osteonecrosis in French survivors of childhood and adolescent leukemia: a clinical and MRI study of LEA cohort.

Osteonecrosis (ON) is a known complication of acute leukemia (AL) management, affecting 1%-10% of young patients and resulting in long-term morbidity. Widespread access to MRI over the past decade has allowed earlier detection and more accurate assessment. This study investigated clinical and MRI features of the 129 (2.5%) patients with symptomatic ON retrospectively recruited from the French LEA (Leucémies de l'Enfant et de l'Adolescent, or child and adolescent leukemias) cohort (n = 4,973). We analyzed data concerning ON risk factors, multifocal involvement, severe lesions detected by MRI, and patient quality of life (QoL). ON patients tended to be >10 years old at the time of AL diagnosis (odds ratio [OR]: 22.46; p < 10-6), female (OR: 1.8; p = 0.002), or treated for relapse (OR: 1.81; p = 0.041). They more frequently suffered from other sequelae (p < 10-6). Most necroses involved weight-bearing joints, and they were multifocal in 69% of cases. Double-blinded review of MRIs for 39 patients identified severe lesions in 14, usually in the hips. QoL of adolescents and adults was poor and permanently impacted after onset of ON. In conclusion, age >10 at time of AL diagnosis, female sex, and relapse occurrence were risk factors for multifocal ON; MRI revealed severe ON in a third of the patients considered; and ON was associated with persistently poor QoL affecting multiple domains. Future studies should include prospective data addressing ON management and seek to identify genetic markers for targeted screening enabling early ON detection and treatment.

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.

Therapeutic approach and outcome of children with Philadelphia chromosome-positive acute lymphoblastic leukemia at first relapse in the era of tyrosine kinase inhibitors: An SFCE retrospective study.

BACKGROUND: Since the introduction of tyrosine kinase inhibitors (TKIs), the profile of pediatric relapse of Philadelphia chromosome-positive acute lymphoblastic leukemia (Ph+ ALL) has changed. However, the management of pediatric Ph+ ALL relapses is not currently standardized. PROCEDURE: We retrospectively analyzed the therapeutic strategies and outcomes of pediatric Ph+ ALL patients in first relapse who were initially treated with a TKI-containing regimen in one of the French pediatric hematology centers from 2004 to 2019. RESULTS: Twenty-seven children experienced a Ph+ ALL relapse: 24 (89%) had an overt relapse and three a molecular relapse. Eight involved the central nervous system. A second complete remission (CR2) was obtained for 26 patients (96%). Induction consisted of nonintensive chemotherapy for 13 patients (48%) and intensive chemotherapy for 14 (52%). Thirteen patients (48%) received consolidation. Allogenic hematopoietic stem cell transplantation (alloHSCT) was performed for 21 patients (78%). The TKI was changed for 23 patients (88%), mainly with dasatinib (n = 15). T315I was the most common mutation at relapse (4/7). The 4-year event-free survival and survival rates were 60.9% and 76.1%, respectively. Survival was positively associated with alloHSCT in CR2. CONCLUSION: We show that pediatric first-relapse Ph+ ALL reinduces well with a second course of TKI exposure, despite the use of different therapeutic approaches. The main prognostic factor for survival was alloHSCT in CR2. Because of the small size of the cohort, we could not draw any conclusions about the respective impact of TKIs, but the predominance of the T315I mutation should encourage careful consideration of the TKI choice.

Socio-economic outcomes among long-term childhood acute lymphoblastic leukaemia survivors enrolled between 1971 and 1998 in EORTC CLG studies: Results of the 58LAE study.

OBJECTIVE: The objective of this study is to evaluate the socio-economic outcomes of survivors of childhood acute lymphoblastic leukaemia (ALL). METHODS: Childhood ALL adult survivors, enrolled in EORTC trials between 1971 and 1998 in France and Belgium, were invited to fill out a questionnaire with information about their socio-economic situation (living with a partner, having a university degree, having a job, working part time and history of having a paid job). The outcomes were compared with two matched control populations. RESULTS: Among 1418 eligible patients, 507 (35.8%) participated, including 39 (8%) and 61 (12%) patients who received a haematopoietic stem cell transplantation (HSCT) and a cranial radiotherapy (CRT), respectively. The median time to follow-up was 20 years, and median age was 25 years. Survivors showed a socio-economic level at least as good as controls. HCST and CRT were associated with a higher probability of not obtaining a bachelor degree (respectively OR = 3.49, 95% CI: 1.46-8.35 and OR = 2.31, 95% CI: 1.04-5.15), HSCT was associated with unemployment (OR = 2.89, 95% CI: 1.09-7.65) and having a relapse was associated with a higher probability of not having a partner (OR = 1.88, 95% CI: 1.01-3.51) adjusting for confounders. CONCLUSION: Childhood ALL survivors showed a high level of socio-economic participation. HCST and CRT were associated with poorer functioning.

A circulating subset of BRAFV600E -positive cells in infants with high-risk Langerhans cell histiocytosis treated with BRAF inhibitors.

BRAF inhibitors are an effective treatment for BRAFV600E -mutated, risk-organ-positive Langerhans cell histiocytosis (RO+ LCH). However, cell-free BRAFV600E DNA often persists during therapy and recurrence frequently occurs after therapy discontinuation. To identify a pathological reservoir of BRAFV600E -mutated cells, we studied peripheral blood cells obtained from six infants with RO+ multisystem (MS) LCH that received targeted therapy. After cell sorting, the BRAFV600E mutation was detected in monocytes (n = 5), B lymphocytes (n = 3), T lymphocytes (n = 2), and myeloid and plasmacytoid dendritic cells (n = 2 each). This biomarker may offer an interesting tool for monitoring the effectiveness of new therapeutic approaches for weaning children with RO+ LCH from targeted therapy.

Recurrent bacterial infections, but not fungal infections, characterise patients with ELANE-related neutropenia: a French Severe Chronic Neutropenia Registry study.

Among 143 patients with elastase, neutrophil-expressed (ELANE)-related neutropenia enrolled in the French Severe Chronic Neutropenia Registry, 94 were classified as having severe chronic neutropenia (SCN) and 49 with cyclic neutropenia (CyN). Their infectious episodes were classified as severe, mild or oral, and analysed according to their natural occurrence without granulocyte-colony stimulating factor (G-CSF), on G-CSF, after myelodysplasia/acute leukaemia or after haematopoietic stem-cell transplantation. During the disease's natural history period (without G-CSF; 1913 person-years), 302, 957 and 754 severe, mild and oral infectious events, respectively, occurred. Among severe infections, cellulitis (48%) and pneumonia (38%) were the most common. Only 38% of episodes were microbiologically documented. The most frequent pathogens were Staphylococcus aureus (37·4%), Escherichia coli (20%) and Pseudomonas aeruginosa (16%), while fungal infections accounted for 1%. Profound neutropenia (<200/mm3 ), high lymphocyte count (>3000/mm3 ) and neutropenia subtype were associated with high risk of infection. Only the p.Gly214Arg variant (5% of the patients) was associated with infections but not the overall genotype. The first year of life was associated with the highest infection risk throughout life. G-CSF therapy achieved lower ratios of serious or oral infectious event numbers per period but was less protective for patients requiring >10 µg/kg/day. Infections had permanent consequences in 33% of patients, most frequently edentulism.

Invasive Fungal Infections in Immunocompromised Children: Novel Insight Following a National Study.

OBJECTIVE: To obtain a national overview of the epidemiology and management of invasive fungal infections (IFIs) in France for severely immunocompromised children who were treated for acute leukemia or had undergone allogeneic hematopoietic stem cell transplantation (a-HSCT). STUDY DESIGN: We performed a national multicenter retrospective study to collect epidemiologic data for proven and probable IFIs in children with acute leukemia under first- line or relapse treatment or who had undergone a-HSCT. We also conducted a prospective practice survey to provide a national overview of IFI management in pediatric hematology units. RESULTS: From January 2014 to December 2017, 144 cases of IFI were diagnosed (5.3%) in 2721 patients, including 61 cases of candidiasis, 60 cases of aspergillosis, and 23 cases of infection with "emergent" fungi, including 10 cases of mucormycosis and 6 cases of fusariosis. The IFI rate was higher in patients with acute myelogenous leukemia (12.9%) (OR, 3.24; 95% CI, 2.15-4.81; P < .0001) compared with the rest of the cohort. Patients undergoing a-HSCT had an IFI rate of only 4.3%. In these patients, the use of primary antifungal prophylaxis (principally fluconazole) was associated with a lower IFI rate (OR, 0.28; 95% CI, 0.14-0.60; P = 4.90 ×10-4) compared with a-HSCT recipients who did not receive antifungal prophylaxis. The main cause of IFI in children receiving prophylaxis was emergent pathogens (41%), such as mucormycosis and fusariosis, which were resistant to the prophylactic agents. CONCLUSIONS: The emerging fungi and new antifungal resistance profiles uncovered in this study should be considered in IFI management in immunocompromised children.

Fertility status among long-term childhood acute lymphoblastic leukaemia survivors enrolled between 1971 and 1998 in EORTC CLG studies: results of the 58 Late Adverse Effects study.

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, <18 years old at diagnosis and alive and ≥18 years at follow-up were eligible. Among 1418 eligible survivors, 507 (35.8%) participated (277 females, 230 males). Controls from the general population matched one to one by age, province, level of urbanization and sex could be identified for 503 survivors. 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).

Should treatment of ALK-positive anaplastic large cell lymphoma be stratified according to minimal residual disease?

In anaplastic lymphoma kinase (ALK)-positive anaplastic large cell lymphoma (ALK+ ALCL), positive minimal residual disease (MRD+) after the first chemotherapy course was proven of strong prognostic significance. We aimed to validate these results in 138 French patients. Eighty-seven patients had a detectable minimal disseminated disease at diagnosis (MDD+). Early MRD assessment was performed in 33 of 87 patients and was positive in 18 and negative in 15 (MRD-). Three-year progression-free survival was significantly correlated with the MDD/MRD status: 81.1% in MDD-, 69.6% in MDD+/MRD-, and 15.2% in MDD+/MRD+ patients. In conclusion, we confirmed on an independent cohort that the MDD/MRD status has strong prognosis significance in ALK+ ALCL.

Long-term follow-up of children with risk organ-negative Langerhans cell histiocytosis after 2-chlorodeoxyadenosine treatment.

The nucleoside analogue, 2-chlorodeoxyadenosine (2CDA), was reported to be an active treatment for childhood Langerhans cell histiocytosis (LCH) without risk organ (RO-) involvement. However, we lack data on long-term effects of 2CDA treatment, including the disease reactivation rate, permanent sequelae and long-term tolerance. This study included 44 children from the French LCH registry, treated for a RO- LCH with 2CDA monotherapy (median number of six courses). The median age at the beginning of 2CDA was 3·6 years (range, 0·3-19·7 years) and the median follow-up after was 5·4 years (range, 0·6-15·1 years). Objective response to 2CDA was observed in 25 patients (56·8%), while six patients (13·6%) had stable disease and 13 patients (29·5%) exhibited progressive disease. Among patients without progression, only two experienced disease reactivation after 2CDA discontinuation. The five-year cumulative incidence of disease progression or reactivation after 2CDA therapy initiation was 34·3%. The lymphopenia reported in all cases [72% below absolute lymphocyte count (ALC) of 0·5 G/l], was addressed with appropriate prophylactic measures. Other toxicities above grade 2 were uncommon, and no second malignant neoplasm or neuropathy was reported. The five-year overall survival was 97·7%. In conclusion, we could confirm that 2CDA monotherapy was a beneficial long-term therapy for treating patients with RO- LCH. Appropriate management of induced immune deficiency is mandatory.

Long-term outcome evaluation of medium/high risk acute lymphoblastic leukaemia children treated with or without cranial radiotherapy in the EORTC 58832 randomized study.

We investigated the long-term outcome, the incidence of second neoplasms (SN) and the rate of late adverse effects (LAE) in children with central nervous system (CNS) negative medium/high-risk de novo acute lymphoblastic leukaemia (ALL), in first complete remission (CR1) at end of late intensification, randomized to receive no cranial radiotherapy (No CRT, n = 92) versus CRT (standard arm, n = 84) in the non-inferiority EORTC 58832 study (1983-1989). Median follow-up was 20 years (range 4-32 years). The 25-year disease-free survival rate (±SE) was 67·4 ± 4·9% without CRT and 70·2 ± 5·0% with CRT. The 25-year incidence of isolated (6·5 ± 2·6% vs. 4·8 ± 2·3%) and any CNS relapse {8·7 ± 2·9% vs. 11·9 ± 3·5%; hazard ratio (HR) 0·71 [95% confidence interval (CI) 0·28-1·79]; test of non-inferiority: P = 0·01} was not increased without CRT. The 25-year SN incidence in CR1 was 7·9 ± 4·6% vs. 11·0 ± 4·2%. The 25-year event-free and overall survival rates were quite similar in both arms [59·5 ± 6·3% vs. 60·5 ± 5·9%, HR 0·94 (95% CI 0·57-1·52), and 78·1 ± 4·3% vs. 78·5 ± 4·5%, HR 1·00 (95% CI 0·53-1·88)]. Omission of CRT was associated with dramatic decrease in CNS and endocrine LAE rates. In conclusion, our data suggest that, with proper systemic and intrathecal CNS prophylaxis, CRT could totally be omitted in CR1 without jeopardizing survival, while decreasing LAE in childhood ALL.

Pediatric randomized trial EORTC CLG 58951: Outcome for adolescent population with acute lymphoblastic leukemia.

Over the years, the prognosis of adolescents treated for acute lymphoblastic leukemia (ALL) has improved. However, this age group still represents a challenge with an overall survival (OS) of 60% compared to 85% in younger children. Herein, we report the outcome of adolescents treated in the European Organisation for Research and Treatment of Cancer (EORTC) 58951 clinical trial. EORTC 58951 clinical trial included patients with de novo ALL between 1998 and 2008. For this study, we analyzed data of all adolescents between 15 and under 18. Data from 97 adolescents were analyzed, 70 had B-lineage and 27 had T-lineage ALL. The 8-year event-free survival (EFS) and OS for the B-cell precursor ALL cases were 72.3% (59.4%-81.7%) and 80.8% (67.4%-89.1%), respectively. For the T-lineage, the 8-year EFS and OS were 57.4% (36.1%-74.0%) and 59.0% (36.1%-76.2%), respectively. "B-other" ALL, defined as BCP-ALL lacking any known recurrent genetic abnormalities were more frequent in our adolescent population (52.8%) than in younger children (27.1%). Outcome of adolescents in the EORTC 58951 study is supporting the findings that adolescents have better outcome in pediatric compared to adults' trials. Nevertheless, in pediatric studies, adolescents still have a worse prognosis than younger children. Despite the fact that specific unfavorable characteristics may be linked to the adolescent population, a careful study and characterization of adolescents "B-other" genetic abnormalities in ALL is critical to improve the outcome of this population.

Results of successive EORTC-CLG 58 881 and 58 951 trials in paediatric T-cell acute lymphoblastic leukaemia (ALL).

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 <100 × 109 /l and "good responders" to prephase. Medac E. coli asparaginase was associated with longer EFS [hazard ratio (HR) 0·54, P = 0·0015] and overall survival (HR 0·51, P = 0·0018). Induction therapy with dexamethasone did not improve EFS compared to prednisolone. Remarkably, intensification of central nervous system (CNS)-directed therapy in trial 58951 resulted in fewer bone marrow relapses, while the incidence of CNS relapses remained low. In summary, we showed that adequate asparaginase therapy, intensified induction treatment and intensification of CNS-directed chemotherapy can result in an improvement of outcome in T-ALL patients with good prephase response and initial WBC counts <100 × 109 /l, representing approximately 50% of T-ALL patients.

Outcome of relapse in children and adolescents with B-cell non-Hodgkin lymphoma and mature acute leukemia: A report from the French LMB study.

INTRODUCTION: In order to describe relapsed B-cell non-Hodgkin lymphoma and mature acute leukemia in children/adolescents treated with the Lymphomes Malins B (LMB) regimen and their outcome in the rituximab era, relapses in the French LMB2001 study were reviewed. METHODS: Between February 2001 and December 2011, 33 patients out of 773 (4.3%) relapsed; 27 had Burkitt lymphoma and six large B-cell histology. Median age at diagnosis was 10.1 years. One patient was initially treated in risk group A, 21 in group B, and 11 in group C. RESULTS: Median time to relapse after diagnosis was 4.5 months (range 2.4-13.6). Thirty-two patients received salvage therapy. Twenty-seven received rituximab mainly in addition to high-dose cytarabine and etoposide (n = 18) and/or ifosfamide, carboplatin, and etoposide (n = 7). First-line salvage chemotherapy response rate was 66% with 47% being complete remission (CR). Twenty-one patients received high-dose chemotherapy (HDC) followed by autologous (n = 13) or allogeneic (n = 8) transplant. With a median follow-up of 6.8 years, the 5-year survival rate after relapse was 36.4% (95% confidence interval [CI] 22-53%). Twelve patients were still alive; all but one (group A) received consolidation treatment. Achieving CR before consolidation was significantly associated with better survival, with a 5-year survival rate of 75% (95% CI 46.8-91.1%) for patients in CR before HDC, 33% (95% CI 9.7-70%) for patients in partial remission, and 0% for nonresponders (P = .033). CONCLUSION: Survival of children/adolescents with mature B-cell lymphoma/leukemia remains poor after relapse with no apparent improvement with rituximab. Response rates to salvage chemo-immunotherapies are insufficient and new drugs are urgently needed to improve disease control.

First Report of a Patient with MPS Type VII, Due to Novel Mutations in GUSB, Who Underwent Enzyme Replacement and Then Hematopoietic Stem Cell Transplantation.

We report the case of a boy who was diagnosed with mucopolysaccharidosis (MPS) VII at two weeks of age. He harbored three missense ß-glucuronidase (GUSB) variations in exon 3: two novel, c.422A>C and c.424C>T, inherited from his mother, and the rather common c.526C>T, inherited from his father. Expression of these variations in transfected HEK293T cells demonstrated that the double mutation c.422A>C;424C>T reduces ß-glucuronidase enzyme activity. Enzyme replacement therapy (ERT), using UX003 (vestronidase alfa), was started at four months of age, followed by a hematopoietic stem cell allograft transplantation (HSCT) at 13 months of age. ERT was well tolerated and attenuated visceromegaly and skin infiltration. After a severe skin and gut graft-versus-host disease, ERT was stopped six months after HSCT. The last follow-up examination (at the age of four years) revealed a normal psychomotor development, stabilized growth curve, no hepatosplenomegaly, and no other organ involvement. Intriguingly, enzyme activity had normalized in leukocytes but remained low in plasma. This case report illustrates: (i) The need for an early diagnosis of MPS, and (ii) the possible benefit of a very early enzymatic and/or cellular therapy in this rare form of lysosomal storage disease.

Incidence and risk factors for clinical neurodegenerative Langerhans cell histiocytosis: a longitudinal cohort study.

Neurodegenerative (ND) complications in Langerhans cell histiocytosis (LCH) are a late-onset but dramatic sequelae for which incidence and risk factors are not well defined. Based on a national prospective registry of paediatric LCH patients, we determined the incidence rate of clinical ND LCH (cND-LCH) and analysed risk factors, taking into account disease extent and molecular characteristics. Among 1897 LCH patients, 36 (1·9%) were diagnosed with a cND-LCH. The 10-year cumulative incidence of cND-LCH was 4·1%. cND-LCH typically affected patients previously treated for a multisystem, risk organ-negative LCH, represented in 69·4% of cND-LCH cases. Pituitary gland, skin and base skull/orbit bone lesions were more frequent (P < 0·001) in cND-LCH patients compared to those without cND-LCH (respectively 86·1% vs. 12·2%, 75·0% vs. 34·2%, and 63·9% vs. 28·4%). The 'cND susceptible patients' (n = 671) i.e., children who had experienced LCH disease with pituitary or skull base or orbit bone involvement, had a 10-year cND risk of 7·8% vs. 0% for patients who did not meet these criteria. Finally, BRAFV600E status added important information among these cND susceptible patients, with the 10-year cND risk of 33·1% if a BRAFV600E mutation was present compared to 2·9% if it was absent (P = 0·002).

Circulating cell-free BRAFV600E as a biomarker in children with Langerhans cell histiocytosis.

The BRAFV600E mutation is reported in half of patients with Langerhans cell histiocytosis (LCH). This study investigated the detection of the BRAFV600E allele in circulating cell-free (ccf) DNA in a paediatric LCH cohort. Children with BRAFV600E -mutated LCH were investigated to detect ccf BRAFV600E at diagnosis (n = 48) and during follow-up (n = 17) using a picolitre-droplet digital PCR assay. At diagnosis, ccf BRAFV600E was positive in 15/15 (100%) patients with risk-organ positive multisystem (RO+ MS) LCH, 5/12 (42%) of patients with RO- MS LCH and 3/21 (14%) patients with single-system (SS) LCH (P < 0·001, Fisher's exact test). The positive BRAFV600E load was higher for RO+ patients (mean, 2·90%; range, 0·04-11·4%) than for RO- patients (mean, 0·16%; range, 0·01-0·39) (P = 0·003, Mann-Whitney U test). After first-line vinblastine-steroid induction therapy, 7/7 (100%) of the non-responders remained positive for ccf BRAFV600E compared to 2/4 (50%) of the partial-responders and 0/4 of the complete responders (P = 0·002, Fisher's exact test). Six children treated with vemurafenib showed a clinical response that was associated with a decrease in the ccf BRAFV600E load at day 15. Thus, ccf BRAFV600E is a promising biomarker for monitoring the response to therapy for children with RO+ MS LCH or RO- LCH resistant to first-line chemotherapy.

Prolonged versus standard native E. coli asparaginase therapy in childhood acute lymphoblastic leukemia and non-Hodgkin lymphoma: final results of the EORTC-CLG randomized phase III trial 58951.

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.

The Impact of Donor Type on Long-Term Health Status and Quality of Life after Allogeneic Hematopoietic Stem Cell Transplantation for Childhood Acute Leukemia: A Leucémie de l'Enfant et de L'Adolescent Study.

We compared the long-term impact of donor type (sibling donor [SD] versus matched unrelated donor [MUD] or umbilical cord blood [UCB]) on late side effects and quality of life (QoL) in childhood acute leukemia survivors treated with hematopoietic stem cell transplantation. We included 314 patients who underwent transplantation from 1997 to 2012 and were enrolled in the multicenter French Leucémie de l'Enfant et de L'Adolescent ("Leukemia in Children and Adolescents") cohort. More than one-third of the patients were adults at last visit; mean follow-up duration was 6.2 years. At least 1 late effect was observed in 284 of 314 patients (90.4%). The average number of adverse late effects was 2.1 ± .1, 2.4 ± .2, and 2.4 ± .2 after SD, MUD, and UCB transplantation, respectively. In a multivariate analysis, considering the SD group as the reference, we did not detect an impact of donor type for most sequelae, with the exception of increased risk of major growth failure after MUD transplantation (odds ratio [OR], 2.42) and elevated risk of osteonecrosis after UCB transplantation (OR, 4.15). The adults and children's parents reported comparable QoL among the 3 groups. Adult patient QoL scores were lower than age- and sex-matched French reference scores for almost all dimensions. We conclude that although these patients are heavily burdened by long-term complications, donor type had a very limited impact on their long-term health status and QoL.