Periosteal Ewing Sarcoma with Distant Metastases: Report of Two Patients and Review of the Literature.

Periosteal Ewing sarcoma (ES) is an exceedingly rare topographic subtype of the ES. To our knowledge, only 60 patients have been reported in the medical English language literature. It predominantly affects men in the second decade of life and arises in the long tubular bone diaphysis. PES rarely develops distant metastases. We report two patients of this rare ES location that were found on the distal tibial shaft and proximal femoral diaphysis of a 21-year-old man and an 8-year-old boy, respectively. Both patients were treated with neoadjuvant chemotherapy, wide resection, and adjuvant chemotherapy. One of our patients had lung metastases at the time of diagnosis and died 5 years later. The other patient presented intramedullary humeral bone metastasis 19 years after diagnosis. There has been no evidence of disease in the 26 years of follow-up. Close follow-up of periosteal ES is recommended because distant metastases may exceptionally occur, even several years after diagnosis.

Severe Impairment of T-cell Immunity and Pulmonary GvHD Are Major Risk Factors for Nontuberculous Mycobacterial Infection After Pediatric Allogeneic Hematopoietic Stem Cell Transplantation.

Hematopoietic stem cell transplant recipients are prone to infectious complications. Infections caused by nontuberculous mycobacteria have increased in adults but literature in children is scarce. We report 6 episodes of disseminated or pulmonary nontuberculous mycobacteria infection among 5 pediatric hematopoietic stem cell transplant recipients. All but one were caused by Mycobacterium avium complex. Four patients died, 2 related to nontuberculous mycobacteria infection.

Outcomes of allogeneic haematopoietic cell transplantation for myelofibrosis in children and adolescents: the retrospective study of the EBMT Paediatric Diseases WP.

This retrospective study evaluated 35 children (median age 5.2 years; range 0.4-18) with myelofibrosis (MF), including 33 with primary myelofibrosis and 2 with secondary myelofibrosis transplanted from matched sibling donor (MSD) (n = 17) or non-MSD (n = 18) between 2000 and 2022. Conditioning was usually chemotherapy-based (n = 33) and myeloablative (n = 32). Fifteen patients received bone marrow (BM), 14 haematopoietic cells (HC) from peripheral blood (PB), and 6 from cord blood (CB). Day +100 acute GvHD II-IV incidence was significantly lower after MSD-haematopoietic cell transplantation (MSD-HCT) than after non-MSD-HCT [18.8% (4.3-41.1) vs 58.8% (31-78.6); p = 0.01]. Six-year non-relapse mortality (NRM) was 18% (7.1-32.8), relapse incidence was 15.9% (5.6-30.9), progression-free survival (PFS) was 66.1% (47-79.7), GvHD-free relapse-free survival was 50% (30.6-66.7), and overall survival (OS) was 71.1% (51.4-84). Six-year PFS and OS were significantly higher after BM transplantation compared to HCT from other sources [85.1% (52.3-96.1) vs 50.8% (26.3-71), p = 0.03, and 90.9% (50.8-98.7) vs 54% (28.1-74.2), p = 0.01, respectively], whereas NRM was significantly lower [0% vs 32% (12.3-53.9); p = 0.02]. This first multicentre study on outcomes of allogeneic HCT in children with myelofibrosis proves feasibility and curative effect of transplantation in these children, suggests that bone marrow transplantation is associated with better outcomes, and indicates the need for further studies.

Mismatched related donor allogeneic haematopoietic cell transplantation compared to other donor types for Ph+ chronic myeloid leukaemia: A retrospective analysis from the Chronic Malignancies Working Party of the EBMT.

Allogeneic haematopoietic cell transplantation (allo-HCT) remains an option for tyrosine kinase inhibitor-resistant chronic myeloid leukaemia (CML) in first chronic phase (CP1) and high-risk patients with advanced disease phases. In this European Society for Blood and Marrow Transplantation (EBMT) registry-based study of 1686 CML patients undergoing first allo-HCT between 2012 and 2019, outcomes were evaluated according to donor type, particularly focusing on mismatched related donors (MMRDs). Median age at allo-HCT was 46 years (IQR 36-55). Disease status was CP1 in 43%, second CP (CP2) or later in 27%, accelerated phase in 12% and blast crisis in 18%. Donor type was matched related (MRD) in 39.2%, MMRD in 8.1%, matched unrelated (MUD) in 40.2%, and mismatched unrelated (MMUD) in 12.6%. In 4 years, overall survival (OS) for MRD, MMRD, MUD and MMUD was 61%, 56%, 63% and 59% (p = 0.21); relapse-free survival (RFS) was 48%, 42%, 52% and 46% (p = 0.03); cumulative incidence of relapse (CIR) was 33%, 37%, 27% and 30% (p = 0.07); non-relapse mortality (NRM) was 19%, 21%, 21% and 24% (p = 0.21); and graft-versus-host disease (GvHD)-free/relapse-free survival (GRFS) was 16%, 18%, 22% and 15% (p = 0.05) respectively. On multivariate analysis, MMRD use associated with longer engraftment times and higher risk of graft failure compared to MRD or MUD. There was no statistical evidence that MMRD use associated with different OS, RFS and incidence of GvHD compared to other donor types.

The paradigm of total body irradiation in acute lymphoblastic leukaemia: Therapeutic effectiveness versus the challenges of toxicity.

INTRODUCTION: Total body irradiation (TBI) is part of the myeloablative conditioning for hematopoietic stem cell transplantation (HSCT) in malignant hematologic disorders. This therapy has recently shown improved survival in acute lymphoblastic leukemia (ALL) compared to chemotherapy-based regimens. However, side effects are a significant limitation, especially in the pediatric population. PATIENTS AND METHODS: We retrospectively analyzed the survival of patients with ALL who underwent an HSCT at a tertiary hospital between 1996 and 2009 (N = 69 HSCT in 57 patients). We differentiated a cohort that received TBI (N = 44) from another that did not (N = 25). Subsequently, we interviewed the survivors from the TBI group with a minimum of 10 years of follow-up (N = 18), asking about the presence of side effects. RESULTS: The overall survival (OS) at 2 and 5 years was 79.1% and 65.2% respectively for the TBI group and 66.2% and 55.8% for the non-TBI group, although this difference was not significant (P=.31). The event-free survival (EFS) at 2 and 5 years was 77.3% and 63.6% respectively for the TBI group and 56% and 32% for the non-TBI group (P=.02). The probability of relapse (PR) at 2 years for those who received TBI was 10% compared to 28.6% for those who did not receive TBI (P=.005). Survivors who received TBI developed secondary neoplasms (39%), dyslipidemia (67%), cognitive impairments affecting memory (44%), recurrent respiratory infections (39%), thyroid abnormalities (45%), premature ovarian failure (89%), cataracts (22%), and psychological problems (44%). However, the quality of life, as self-assessed by the patients, was considered good for 83% of the participants.. CONCLUSIONS: Patients who received TBI had significantly higher EFS and lower PR. However, adverse effects are frequent and significant, although they do not subjectively affect quality of life.

Use of Eculizumab in Pediatric Patients with High-Risk Transplantation-Associated Thrombotic Microangiopathy: Outcomes and Risk Factors Associated with Response and Survival. A Retrospective Study on Behalf of the Spanish Group for Hematopoietic Transplantation and Cellular Therapy (GETH-TC).

Transplantation-associated thrombotic microangiopathy (TA-TMA) is associated with high morbidity and mortality. Although survival has improved significantly with the introduction of eculizumab, the need for improvement remains, especially in high-risk patients. This study aimed to describe the results obtained with eculizumab in a pediatric cohort with the attempt to define which risk factors could determine the response to treatment. We designed a national multicenter retrospective study of children treated with eculizumab for high-risk TA-TMA. The study cohort comprised 29 patients who had undergone a first (n = 28) or second (n = 1) allogeneic hematopoietic stem cell transplantation (HSCT) for malignant (n = 17) or nonmalignant (n = 12) disease. The median time from HSCT to TA-TMA diagnosis was 154 days (interquartile range [IQR], 103 to 263 days). Eleven patients (38%) who were initially diagnosed with low- to intermediate-risk TA-TMA progressed to high-risk TA-TMA (hrTA-TMA), within a median time of 4 days (IQR, 1 to 33 days). SC5b-9 was increased in 90% of 20 patients in whom it was measured. Renal (n = 12), pulmonary (n = 1), and intestinal (n = 1) biopsy confirmed the diagnosis in 12 of 14 patients (85%). Seventeen patients (58%) had extrarenal involvement with serositis (n = 13; 44,8%), pulmonary (n = 12; 41,4%), gastrointestinal (n = 8; 27.6%), cardiovascular (n = 7; 24.1%), or central nervous system (CNS) (n = 2; 6.9%) involvement. The median time from hrTA-TMA diagnosis to the initiation of eculizumab was 7 days (IQR, 1 to 8 days). Overall, 19 patients (65.5%) responded to eculizumab, of whom 17 (58.6%) achieved a complete response and 2 (6.9%) achieved a partial response. The remaining 10 patients (34.5%) did not show any of response. The overall response rate to eculizumab for TA-TMA was 27.59% (95% confidence interval [CI], 14.87% to 47.66%) at 1 month, 55.17% (95% CI, 38.43% to 73.48%) at 3 months, and 62.07% (95% CI, 45.10% to 79.13%) at 6 months after eculizumab initiation. In multivariate analysis, the pulmonary involvement decreased the probability of response (hazard ratio [HR], .18; P = .0298). The 1-year overall survival (OS) was 55.2% (95% CI, 35.6% to 71.0%) for the whole cohort and 83.3% (95% CI, 56.7% to 94.3%) for patients who responded to eculizumab. Pulmonary involvement (HR, 14.93; P = .0043) and CNS involvement (HR, 8.63; P = .0497) were associated with a statistically significant decrease in survival. We found that patients diagnosed with hrTA-TMA with pulmonary involvement had a poor response to eculizumab, and that patients with pulmonary and CNS involvement had significantly decreased survival. Given these results, we hypothesize that providing eculizumab therapy at an early stage of the disease before organ damage is established might significantly improve the response and, consequently, survival.

Neuropsychological and biopsychosocial evolution, therapeutic adherence and unmet care needs during paediatric transplantation: study protocol of a mixed-methods design (observational cohort study and focus groups) - the TransplantKIDS mental health project.

The present article describes the protocol of a mixed-methods study (an observational cohort design and focus groups), aimed to examine neuropsychological functioning and other biopsychosocial outcomes, therapeutic adherence and unmet care needs in paediatric population undergoing solid organ or allogeneic hematopoietic transplant during the pre- and post-transplant phases. Following a multi-method/multi-source approach, neuropsychological domains will be comprehensively measured with objective tests (SDMT, K-CPT 2/CPT 3, TAVECI/TAVEC, WISC-V/WAIS-IV Vocabulary and Digit Span subtests, Verbal Fluency tests, Stroop, ROCF, and TONI-4); ecological executive functioning, affective and behavioral domains, pain intensity/interference, sleep quality and therapeutic adherence will be assessed through questionnaires (parent/legal guardians-reported: BRIEF-2 and BASC-3; and self-reported: BASC-3, BPI, PROMIS, AIQ and SMAQ); and blood levels of prescribed drugs will be taken from each patient's medical history. These outcomes will be measured at pre-transplant and at 4-weeks and 6-months post-transplant phases. The estimated sample size was 60 patients (any type of transplant, solid organ, or hematopoietic) from La Paz University Hospital (Madrid, Spain). Finally, three focus group sessions will be organized with patients, parents/guardians, and transplant clinicians (n = 15, with 5 participants per group), in order to qualitatively identify unmet care needs during the pre-, and post-transplant stages of the process. The study protocol was registered at ClinicalTrials.gov (NCT05441436).

Hematopoietic stem cell transplantation in children with chronic granulomatous disease: the Spanish experience.

Introduction: Hematopoietic stem cell transplantation (HCT) can cure chronic granulomatous disease (CGD). However, transplant-associated morbidity or mortality may occur, and it is still controversial which patients benefit from this procedure. The aim of this retrospective study was to evaluate the outcome of pediatric patients who received HCT in one of the Spanish pediatric transplant units. Results: Thirty children with a median age of 6.9 years (range 0.6-12.7) were evaluated: 8 patients received a transplant from a sibling donor (MSD), 21 received a transplant from an unrelated donor (UD), and 1 received a haploidentical transplant. The majority of the patients received reduced-intensity conditioning regimens based on either busulfan plus fludarabine or treosulfan. Relevant post-HCT complications were as follows: i) graft failure (GF), with a global incidence of 28.26% (CI: 15.15-48.88), 11.1% in patients with MSD (1.64-56.70) and 37.08% in unrelated donors (19.33-63.17); and ii) chronic graft-versus-host disease (GVHD), with an incidence of 20.5% (8.9-43.2), 11.1% in patients with MSD (1.64-56.70) and 26.7% in unrelated donors (10.42-58.44). Post-HCT infections were usually manageable, but two episodes of pulmonary aspergillosis were diagnosed in the context of graft rejection. The 2-year OS was 77.3% (55.92-89.23). There were no statistically significant differences among donor types. Discussion: HCT in patients with CGD is a complex procedure with significant morbidity and mortality, especially in patients who receive grafts from unrelated donors. These factors need to be considered in the decision-making process and when discussing conditioning and GVHD prophylaxis.

Corrigendum: Impact of disease burden and late loss of B cell aplasia on the risk of relapse after CD19 chimeric antigen receptor T Cell (Tisagenlecleucel) infusion in pediatric and young adult patients with relapse/refractory acute lymphoblastic leukemia: role of B-cell monitoring.

[This corrects the article DOI: 10.3389/fimmu.2023.1280580.].

The challenge of standardizing CAR-T cell monitoring: A comparison of two flow-cytometry methods and correlation with qPCR technique.

Chimeric antigen receptor (CAR) T-cell therapy is a breakthrough in hematologic malignancies, such as acute B lymphoblastic leukemia (B-ALL). Monitoring this treatment is recommended, although standardized protocols have not been developed yet. This work compares two flow cytometry monitoring strategies and correlates this technique with qPCR method. CAR-T cells were detected by two different flow-cytometry protocols (A and B) in nine blood samples from one healthy donor and five B-ALL patients treated with Tisagenlecleucel (Kymriah®, USA). HIV-1 viral load allowed CAR detection by qPCR, using samples from seven healthy donors and nine B-ALL patients. CAR detection by protocol A and B did not yield statistically significant differences (1.9% vs. 11.8% CD3 + CAR+, p = 0.07). However, protocol B showed a better discrimination of the CD3 + CAR+ population. A strong correlation was observed between protocol B and qPCR (r = 0.7, p < 0.0001). CD3 + CAR+ cells were detected by flow cytometry only when HIV-1 viral load was above 104 copies/mL. In conclusion, protocol B was the most specific flow-cytometry procedure for the identification of CAR-T cells and showed a high correlation with qPCR. Further efforts are needed to achieve a standardized monitoring approach.

An artificial intelligence-driven predictive model for pediatric allogeneic hematopoietic stem cell transplantation using clinical variables.

BACKGROUND: Hematopoietic stem cell transplantation (HSCT) is a procedure with high morbidity and mortality. Identifying patients for maximum benefit and risk assessment is crucial in the decision-making process. This has led to the development of predictive risk models for HSCT in adults, which have limitations when applied to pediatric population. Our goal was to develop an automatic learning algorithm to predict survival in children with malignant disorders undergoing HSCT. METHODS: We studied allogenic HSCTs performed on children with malignant disorders at a third-level hospital between 1991 and 2021. Survival was analyzed using the Kaplan-Meier method, log-rank test for the univariate analysis, and Cox regression for the multivariate analysis. A prognostic index was constructed based on these findings. Lastly, we constructed a predictive model using a random forest algorithm to forecast 1-year survival after HSCT. RESULTS: We analyzed 229 HSCTs in 201 patients with a median follow-up of 1.64 years. Variables that impacted on the multivariate analysis were older age (hazard ratio [HR] 1.40, 95% confidence interval [CI] 1.12-1.76, p = .003), oldest period of HSCT (HR 0.46, 95% CI 0.29-0.73, p < .001), and mismatched donor (HR 2.65, 95% CI 1.51-4.65, p = .001). Our prognostic index was associated with 3-year overall survival (OS; p < .001). A random forest was developed using as variables: diagnosis, age, year of HSCT, time from diagnosis to HSCT, disease stage, donor type, and conditioning. This achieved 72% accuracy in predicting 1-year OS. CONCLUSIONS: Our index and random forest was effective in predicting 1-year survival. However, further validation in diverse populations is necessary to establish their generalizability.

Translational Aspects of Epithelioid Sarcoma: Current Consensus.

Epithelioid sarcoma (EpS) is an ultra-rare malignant soft-tissue cancer mostly affecting adolescents and young adults. EpS often exhibits an unfavorable clinical course with fatal outcome in ∼50% of cases despite aggressive multimodal therapies combining surgery, chemotherapy, and irradiation. EpS is traditionally classified in a more common, less aggressive distal (classic) type and a rarer aggressive proximal type. Both subtypes are characterized by a loss of nuclear INI1 expression, most often following homozygous deletion of its encoding gene, SMARCB1-a core subunit of the SWI/SNF chromatin remodeling complex. In 2020, the EZH2 inhibitor tazemetostat was the first targeted therapy approved for EpS, raising new hopes. Still, the vast majority of patients did not benefit from this drug or relapsed rapidly. Further, other recent therapeutic modalities, including immunotherapy, are only effective in a fraction of patients. Thus, novel strategies, specifically targeted to EpS, are urgently needed. To accelerate translational research on EpS and eventually boost the discovery and development of new diagnostic tools and therapeutic options, a vibrant translational research community has formed in past years and held two international EpS digital expert meetings in 2021 and 2023. This review summarizes our current understanding of EpS from the translational research perspective and points to innovative research directions to address the most pressing questions in the field, as defined by expert consensus and patient advocacy groups.

NKG2D-CAR memory T cells target pediatric T-cell acute lymphoblastic leukemia in vitro and in vivo but fail to eliminate leukemia initiating cells.

Introduction: Refractory/relapsed pediatric acute leukemia are still clinically challenging and new therapeutic strategies are needed. Interactions between Natural Killer Group 2D (NKG2D) receptor, expressed in cytotoxic immune cells, and its ligands (NKG2DL), which are upregulated in leukemic blasts, are important for anti-leukemia immunosurveillance. Nevertheless, leukemia cells may develop immunoescape strategies as NKG2DL shedding and/or downregulation. Methods: In this report, we analyzed the anti-leukemia activity of NKG2D chimeric antigen receptor (CAR) redirected memory (CD45RA-) T cells in vitro and in a murine model of T-cell acute lymphoblastic leukemia (T-ALL). We also explored in vitro how soluble NKG2DL (sNKG2DL) affected NKG2D-CAR T cells' cytotoxicity and the impact of NKG2D-CAR T cells on Jurkat cells gene expression and in vivo functionality. Results: In vitro, we found NKG2D-CAR T cells targeted leukemia cells and showed resistance to the immunosuppressive effects exerted by sNKG2DL. In vivo, NKG2D-CAR T cells controlled T cell leukemia burden and increased survival of the treated mice but failed to cure the animals. After CAR T cell treatment, Jurkat cells upregulated genes related to proliferation, survival and stemness, and in vivo, they exhibited functional properties of leukemia initiating cells. Discussion: The data here presented suggest, that, in combination with other therapeutic approaches, NKG2D-CAR T cells could be a novel treatment for pediatric T-ALL.

Treosulfan-Based Conditioning Regimen In Pediatric Hematopoietic Stem Cell Transplantation: A Retrospective Analysis on Behalf of the Spanish Group for Hematopoietic Transplantation and Cellular Therapy (GETH-TC).

Increasing data on treosulfan-based conditioning regimens before hematopoietic stem cell transplantation (HSCT) demonstrate the consistent benefits of this approach, particularly regarding acute toxicity. This study aimed to describe the results of treosulfan-based conditioning regimens in children, focusing on toxicity and outcomes when used to treat both malignant and nonmalignant diseases. This retrospective observational study of pediatric patients treated in Spain with treosulfan-based conditioning regimens before HSCT was based on data collection from electronic clinical records. We studied a total of 160 treosulfan-based conditioning HSCTs to treat nonmalignant diseases (n = 117) or malignant diseases (n = 43) in 158 children and adolescents. The median patient age at HSCT was 5.1 years (interquartile range, 2 to 10 years). The most frequent diagnoses were primary immunodeficiency (n = 42; 36%) and sickle cell disease (n = 42; 36%) in the nonmalignant disease cohort and acute lymphoblastic leukemia (n = 15; 35%) in the malignant disease cohort. Engraftment occurred in 97% of the patients. The median times to neutrophil engraftment (17 days versus 14 days; P = .008) and platelet engraftment (20 days versus 15 days; P = .002) were linger in the nonmalignant cohort. The 1-year cumulative incidence of veno-occlusive disease was 7.98% (95% confidence interval [CI], 4.6% to 13.6%), with no significant differences between cohorts. The 1-year cumulative incidence of grade III-IV acute graft-versus-host disease (GVHD) was higher in the malignant disease cohort (18% versus 3.2%; P = .011). Overall, the malignant cohort had both a higher total incidence (9% versus 3%; P < .001) and a higher 2-year cumulative incidence (16% versus 1.9%; P < .001) of total chronic GVHD. The 2-year cumulative transplantation-related mortality was 15%, with no difference between the 2 cohorts. The 5-year overall survival was 80% (95% CI, 72% to 86%) and was higher in the nonmalignant cohort (87% versus 61%; P = .01). The 2-year cumulative incidence of relapse was 25% in the malignant cohort. The 5-year cumulative GVHD-free, relapse-free survival rate was 60% (95% CI, 51% to 70%) and was higher in the nonmalignant cohort (72% versus 22%; P < .001). A treosulfan-based radiation-free conditioning regimen is feasible, achieving a high engraftment rate and 5-year overall survival, and is an emerging option for the first HSCT in nonmalignant diseases.

Intermediate Molecular Phenotypes to Identify Genetic Markers of Anthracycline-Induced Cardiotoxicity Risk.

Cardiotoxicity due to anthracyclines (CDA) affects cancer patients, but we cannot predict who may suffer from this complication. CDA is a complex trait with a polygenic component that is mainly unidentified. We propose that levels of intermediate molecular phenotypes (IMPs) in the myocardium associated with histopathological damage could explain CDA susceptibility, so variants of genes encoding these IMPs could identify patients susceptible to this complication. Thus, a genetically heterogeneous cohort of mice (n = 165) generated by backcrossing were treated with doxorubicin and docetaxel. We quantified heart fibrosis using an Ariol slide scanner and intramyocardial levels of IMPs using multiplex bead arrays and QPCR. We identified quantitative trait loci linked to IMPs (ipQTLs) and cdaQTLs via linkage analysis. In three cancer patient cohorts, CDA was quantified using echocardiography or Cardiac Magnetic Resonance. CDA behaves as a complex trait in the mouse cohort. IMP levels in the myocardium were associated with CDA. ipQTLs integrated into genetic models with cdaQTLs account for more CDA phenotypic variation than that explained by cda-QTLs alone. Allelic forms of genes encoding IMPs associated with CDA in mice, including AKT1, MAPK14, MAPK8, STAT3, CAS3, and TP53, are genetic determinants of CDA in patients. Two genetic risk scores for pediatric patients (n = 71) and women with breast cancer (n = 420) were generated using machine-learning Least Absolute Shrinkage and Selection Operator (LASSO) regression. Thus, IMPs associated with heart damage identify genetic markers of CDA risk, thereby allowing more personalized patient management.

Quantifying the available capacity and resource needs for provision of CAR-T therapies in the National Health Service in Spain: a survey-based study.

OBJECTIVES: To estimate the readiness of Spanish National Health Service (NHS) hospitals to provide chimeric antigen receptor T cell (CAR-T), and to identify and quantify the different resources needed to provide CAR-T considering three scenarios defined by 10, 25 and 50 patients per centre per year. DESIGN: Targeted literature review and quantitative study using a questionnaire and telephone interviews. An algorithm was created to determine hospitals' readiness based on their capacity and capability. All the requirements for quantification were assessed and validated by the steering committee, formed by members of the Spanish Group of Haematopoietic Transplantation and Cell Therapy. A weighting system (from 0 to 1) was established for capability quantification. For resources quantification, a scoring system was established, with 0 points representing the minimum and 3 points the maximum of additional resources that a hospital indicated necessary. SETTING: 40 Spanish hospital centres that perform allogeneic haematopoietic stem cell transplantation were invited to complete the questionnaire for capacity quantification, 28 of which provided valid responses. Nine hospitals participated in the interviews for resource quantification, eight of which had previously been designated by the Ministry of Health (MoH) to provide CAR-T. OUTCOME MEASURE: Current capacity of NHS Spanish sites to administer CAR-T under different theoretical scenarios with varying numbers of procedures, and the potential healthcare resources that would be needed to realise the theoretical capacity requirements. RESULTS: Four hospitals were optimally ready, 17 were somewhat ready and 7 were not ready. The actual extrapolated capacity of the currently designated MoH CAR-T sites would allow treatment of approximately 250 patients per year. Regarding healthcare resource needs, the numbers of haematologists, nurses and beds were the most important limiting factors, and those requiring further growth as patient numbers increased. CONCLUSIONS: Increasing the number of CAR-T-qualified centres and/or increasing resources in the current designated sites are two potential strategies that should be considered to treat CAR-T-eligible patients in Spain.

Haploidentical Hematopoietic Stem Cell Transplantation in Pediatric Patients with Acquired Hypocellular Bone Marrow Failure.

Children with acquired hypocellular bone marrow failure of unknown cause (AHBMF) are usually diagnosed either with severe aplastic anemia (SAA) or refractory cytopenia of childhood (RCC). Patients with AHBMF who lack a matched donor and who failed or relapsed after immunosuppressive therapy (IST) need alternative therapies. Haploidentical hematopoietic stem cell transplantation (haplo-HSCT) offers a curative treatment for these patients. We report a multicenter Spanish experience with haplo-HSCT in pediatric patients with AHBMF. Eleven pediatric patients (SAA, n = 9; RCC, n = 2) underwent haplo-HSCT with different lymphodepletion strategies. Most patients (10 of 11) had previously failed to respond or relapsed after IST. The conditioning regimen was reduced intensity in SAA and myeloablative in RCC. Patients with SAA received low-dose radiotherapy as part of their conditioning regimen. All patients engrafted. Viral reactivation was common (8 of 11). Acute GVHD grade ≥II was seen in 5 patients. Chronic GVHD was diagnosed in 4 of the long-term survivors. Transplantation-associated microangiopathy was a frequent complication in SAA patients and was related to worse outcome. Two patients died of transplantation-related complications. Overall survival was 81%, with a median follow-up of 36 months. Haplo-HSCT can be a successful salvage curative treatment for pediatric patients with AHBMF, but with significant toxicities that must be addressed. Transplantation-associated microangiopathy was the most critical complication.

Inherited human ezrin deficiency impairs adaptive immunity.

BACKGROUND: Inborn errors of immunity (IEI) are a group of monogenic diseases that confer susceptibility to infection, autoimmunity, and cancer. Despite the life-threatening consequences of some IEI, their genetic cause remains unknown in many patients. OBJECTIVE: We investigated a patient with an IEI of unknown genetic etiology. METHODS: Whole-exome sequencing identified a homozygous missense mutation of the gene encoding ezrin (EZR), substituting a threonine for an alanine at position 129. RESULTS: Ezrin is one of the subunits of the ezrin, radixin, and moesin (ERM) complex. The ERM complex links the plasma membrane to the cytoskeleton and is crucial for the assembly of an efficient immune response. The A129T mutation abolishes basal phosphorylation and decreases calcium signaling, leading to complete loss of function. Consistent with the pleiotropic function of ezrin in myriad immune cells, multidimensional immunophenotyping by mass and flow cytometry revealed that in addition to hypogammaglobulinemia, the patient had low frequencies of switched memory B cells, CD4+ and CD8+ T cells, MAIT, γδ T cells, and centralnaive CD4+ cells. CONCLUSIONS: Autosomal-recessive human ezrin deficiency is a newly recognized genetic cause of B-cell deficiency affecting cellular and humoral immunity.

Clinical research with targeted drugs in paediatric oncology.

The development of targeted drugs in paediatric oncology has been notoriously slow, in part due to the peculiarities of this rare and highly heterogeneous population. To provide therapeutic breakthroughs for the highest risk subgroups of childhood cancer, innovative research solutions have been implemented in the last several years by different international collaborative groups and regulators. Here, we discuss and summarise some of these approaches, as well as challenges and unmet needs that are still being addressed. A wide range of topics were covered in this review including molecular diagnosis optimisation, innovative research methodologies, big data approaches, trial enrolment strategies, and improvements in regulation and preclinical research platforms.