Decoding the molecular heterogeneity of pediatric monomorphic post-solid organ transplant lymphoproliferative disorders.

Posttransplant lymphoproliferative disorders (PTLDs) represent a broad spectrum of lymphoid proliferations, frequently associated with Epstein-Barr virus (EBV) infection. The molecular profile of pediatric monomorphic PTLDs (mPTLDs) has not been elucidated, and it is unknown whether they display similar genetic features as their counterpart in adult and immunocompetent (IMC) pediatric patients. In this study, we investigated 31 cases of pediatric mPTLD after solid organ transplantation, including 24 diffuse large B-cell lymphomas (DLBCLs), mostly classified as activated B cell, and 7 cases of Burkitt lymphoma (BL), 93% of which were EBV positive. We performed an integrated molecular approach, including fluorescence in situ hybridization, targeted gene sequencing, and copy number (CN) arrays. Overall, PTLD-BL carried mutations in MYC, ID3, DDX3X, ARID1A, or CCND3 resembling IMC-BL, higher mutational burden than PTLD-DLBCL, and lesser CN alterations than IMC-BL. PTLD-DLBCL showed a very heterogeneous genomic profile with fewer mutations and CN alterations than IMC-DLBCL. Epigenetic modifiers and genes of the Notch pathway were the most recurrently mutated in PTLD-DLBCL (both 28%). Mutations in cell cycle and Notch pathways correlated with a worse outcome. All 7 patients with PTLD-BL were alive after treatment with pediatric B-cell non-Hodgkin lymphoma protocols, whereas 54% of patients with DLBCL were cured with immunosuppression reduction, rituximab, and/or low-dose chemotherapy. These findings highlight the low complexity of pediatric PTLD-DLBCL, their good response to low-intensity treatment, and the shared pathogenesis between PTLD-BL and EBV-positive IMC-BL. We also suggest new potential parameters that could help in the diagnosis and the design of better therapeutic strategies for these patients.

[Cardiovascular risk and insulin resistance in childhood leukemia survivors]. / Riesgo cardiovascular y resistencia insulínica en supervivientes de leucemia infantil.

Introduction: Material and methods: a retrospective study of childhood acute leukemia survivors. Survivors with a diagnosis of leukemia before 16 years of age in a tertiary hospital, during the period of 1998-2018, were selected, who had completed their treatment at least two years earlier. We examined: blood adipokine levels and carbohydrate metabolism, body composition by bioimpedance, and carotid status by ultrasound. Somatometric measures were also taken. Results: the registry showed 82 children diagnosed with acute leukemia, aged between 6 and 16 years. Only 22 met the criteria to be included in the study. Results reveled that 32 % of the sample met the criteria for overweight-obesity, and 36 % had high insulin resistance indexes (IR). Leptin levels were higher in women (15.45 vs. 3.25; p = 0.044) and in obese and overweight subjects, as was the leptin/adiponectin ratio, which rises in the presence of IR (2.52 vs. 0.45; p = 0.037). We observed an increase in carotid intima-media thickness in relation to BMI (0.008; CI, -0.002 to 0.013; p = 0.007) without any association with an increase in fat mass in these patients (0.204; CI, -0.043 to 0.451; p = 0.101). Conclusions: childhood leukemia survivors have a high cardiovascular risk, characterized by an increase in IR, not associated with an increase in fat mass. This risk could justify the implementation of preventive actions in these long-lived patients.

Introducción: Material y métodos: estudio retrospectivo de supervivientes de leucemia aguda en edad infantil. Se seleccionaron aquellos supervivientes con diagnóstico de leucemia antes de los 16 años de edad, en un hospital de tercer nivel y durante el período 1998-2018, que hubieran finalizado su tratamiento como mínimo dos años antes. Se analizaron: niveles de adipokinas y metabolismo hidrocarbonado en sangre, composición corporal mediante bioimpedancia y evaluación ecográfica carotídea. Se tomaron además datos somatométricos. Resultados: de 82 niños con diagnóstico de leucemia aguda, con edades comprendidas entre 6 y 16 años, incluidos en el registro, solamente 22 cumplieron los criterios para ser incluídos en el estudio. Entre los resultados destaca que el 32 % de la muestra cumplían los criterios de sobrepeso-obesidad y el 36 % presentaban índices de resistencia insulínica (RI) elevados. Los niveles de leptina fueron más elevados en las mujeres (15,45 vs. 3,25; p = 0,044) y en los individuos con obesidad o sobrepeso, así como la ratio leptina/adiponectina, que se eleva en presencia de RI (2,52 vs. 0,45; p = 0,037). Se observó un incremento del grosor mediointimal carotídeo en relación con el IMC (0,008; IC: -0,002 a 0,013; p = 0,007) sin asociarse a un aumento de masa grasa en estos pacientes (0,204; IC: -0,043 a 0,451; p = 0,101). Conclusiones: los pacientes supervivientes de leucemia en la edad infantil tienen un riesgo cardiovascular elevado, caracterizado por un aumento de la RI no asociado a aumento de la masa grasa. Este riesgo podría justificar la implementación de medidas preventivas en estos pacientes, cada vez más longevos.

IgD Subtype But Not IgM or Non-Secretory Is a Prognostic Marker for Poor Survival Following Autologous Hematopoietic Cell Transplantation in Multiple Myeloma. Results From the EBMT CALM (Collaboration to Collect Autologous Transplant Outcomes in Lymphomas and Myeloma) Study.

BACKGROUND: The Collaboration to Collect Autologous Transplant Outcomes in Lymphoma and Myeloma (CALM) study has provided an opportunity to evaluate the real-world outcomes of patients with myeloma. The aim of this study was to compare the outcome according to the different subtypes of myeloma using CALM data. PATIENTS: This study compared overall survival (OS), progression-free survival (PFS), and complete remission (CR) and the impact of novel versus non-novel drug containing induction regimens prior to autologous hematopoietic cell transplantation (HCT) of 2802 patients with "usual" and "rare" myelomas. RESULTS: Our data suggest that IgM and non-secretory myeloma have superior PFS and OS compared with IgD myeloma and outcomes comparable to those for usual myeloma. Patients who received novel agent induction had higher rates of CR prior to transplant. Non-novel induction regimens were associated with inferior PFS but no difference in OS. Although not the primary focus of this study, we show that poor mobilization status is associated with reduced PFS and OS, but these differences disappear in multivariate analysis suggesting that poor mobilization status is a surrogate for other indicators of poor prognosis. CONCLUSION: We confirm that IgD myeloma is associated with the worst prognosis and inferior outcomes compared with the other isotypes.

Prognostic impact of early-versus-late responses to different induction regimens in patients with myeloma undergoing autologous hematopoietic cell transplantation: Results from the CALM study by the CMWP of the EBMT.

BACKGROUND: In autologous stem cell transplant (ASCT)-eligible myeloma patients, prolonged induction does not necessarily improve the depth of response. METHOD: We analyzed 1222 ASCT patients who were classified based on (a) the interval between induction and stem cell collection, (b) the type of induction regimen: BID (Bortezomib, IMiDs, and Dexamethasone), Bortezomib-based, or CTD (Cyclophosphamide, Thalidomide, and Dexamethasone), and (c) the time to best response (Early ie, best response within 4 or 5 months, depending on the regimen vs Late; Good ie, VGPR or better vs Poor). RESULTS: The length of induction treatment required to achieve a Good response did not affect PFS (P = .65) or OS (P = .61) post-ASCT. The three types of regimen resulted in similar outcomes: median PFS 31, 27.7 and 30.8 months (P = .31), and median OS 81.7, 92.7, and 77.4 months, respectively (P = .83). On multivariate analysis, neither the type nor the duration of the induction regimen affected OS and PFS, except for Early Good Responders who had a better PFS compared to Early Poor Responders (HR = 1.21, P-value = .02). However, achieving a Good response at induction was associated with a better response (≥VGPR) post-transplant. CONCLUSION: The kinetics of response did not affect outcomes.

Haplo-identical or mismatched unrelated donor hematopoietic cell transplantation for Fanconi anemia: Results from the Severe Aplastic Anemia Working Party of the EBMT.

Allogeneic hematopoietic cell transplantation (HCT) is the only curative option for bone marrow failure or hematopoietic malignant diseases for Fanconi anemia (FA) patients. Although results have improved over the last decades, reaching more than 90% survival when a human leukocyte antigen (HLA)-identical donor is available, alternative HCT donors are still less reported. We compared HCT outcomes using HLA-mismatched unrelated donors (MMUD; n = 123) or haplo-identical donors (HDs), either using only in vivo T cell depletion (n = 33) or T cells depleted in vivo with some type of graft manipulation ex vivo (n = 59) performed for FA between 2000 and 2018. Overall survival (OS) by 24 months was 62% (53-71%) for MMUD, versus 80% (66-95%) for HDs with only in vivo T cell depletion and 60% (47-73%) for HDs with in vivo and ex vivo T cell depletion (p = .22). Event-free survival (EFS) was better for HD-transplanted FA patients with only in vivo T cell depletion 86% (73-99%) than for those transplanted from a MMUD 58% (48-68%) or those with graft manipulation 56% (42-69%) (p = .046). Grade II-IV acute graft-versus-host disease (GVHD) was 41% (MMUD) versus 40% (HDs with no graft manipulation) versus 17% (HDs with T cell depleted graft), (p = .005). No differences were found for the other transplant related outcomes. These data suggest that HDs might be considered as an alternative option for FA patients with better EFS using unmanipulated grafts.