COVID-19 disease in children and adolescents following allogeneic hematopoietic stem cell transplantation: A report from the Turkish pediatric bone marrow transplantation study group.

Background: Data on the risk factors and outcomes for pediatric patients with SARS-CoV-2 infection (COVID-19) following hematopoietic stem cell transplantation (HSCT) are limited.

Objectives: The study aimed to analyze the clinical signs, risk factors, and outcomes for ICU admission and mortality in a large pediatric cohort who underwent allogeneic HSCT prior to COVID-19 infection.

Method: In this nationwide study, we retrospectively reviewed the data of 184 pediatric HSCT recipients who had COVID-19 between March 2020 and August 2022.

Myeloid sarcoma with RBM15::MRTFA (MKL1) mimicking vascular neoplasm.

Extramedullary involvement of acute myeloid leukemia (AML), aka myeloid sarcoma, is a rare phenomenon in acute megakaryoblastic leukemia with RBM15:: MRTFA(MKL1) fusion, which might mimic non-hematologic malignancies. A 7-month-old infant presented with leukocytosis, hepatosplenomegaly, multiple lymphadenopathies, and a solid mass in the right thigh. Initially, the patient was diagnosed with a malignant vascular tumor regarding the expression of vascular markers from the biopsy of the right thigh lesion that was performed after the inconclusive bone marrow biopsy.

Evaluation of health-related quality of life in childhood cancer survivors.

Background: Considering the high survival rates of childhood cancers and their stable incidence, concepts such as quality of life (QOL) and health-related quality of life (HRQOL) are impactful issues that have consistently retained their importance worldwide.

Objective: This study aimed to evaluate HRQOL at least 5 years after treatment in childhood cancer survivors (CCSs) with the hypothesis that their QOL could be adversely affected later in their lives. Additionally, we sought to assess the parents of pediatric CCSs with respect to HRQOL.

Thalassemia-free and graft-versus-host-free survival: outcomes of hematopoietic stem cell transplantation for thalassemia major, Turkish experience.

We report the national data on the outcomes of hematopoietic stem cell transplantation (HSCT) for thalassemia major (TM) patients in Turkey on behalf of the Turkish Pediatric Stem Cell Transplantation Group. We retrospectively enrolled 1469 patients with TM who underwent their first HSCT between 1988 and 2020 in 25 pediatric centers in Turkey. The median follow-up duration and transplant ages were 62 months and 7 years, respectively; 113 patients had chronic graft versus host disease (cGVHD) and the cGVHD rate was 8.

Timing of Initiation of Calcineurin Inhibitors in Pediatric Haploidentical Transplantation with Post-Transplantation Cyclophosphamide: Effects on Survival, Relapse, and Cytokine Release Syndrome.

Background: The use of unmanipulated haploidentical hematopoietic stem cell transplantations (haplo-HSCT) with post-transplant cyclophosphamide (PTCY) in children has emerged as an acceptable alternative to the patients without a matched donor. However, the timing of calcineurin inhibitors (CNIs) used in combination with PTCY is increasingly becoming a topic of controversy.

Method: We evaluated 49 children with acute leukemia who underwent unmanipulated haplo-HSCT with PTCY according to the initiation day of CNIs (pre- or post-cyclophosphamide [CY]).

Different Kinetics and Risk Factors for Isolated Extramedullary Relapse after Allogeneic Hematopoietic Stem Cell Transplantation in Children with Acute Leukemia.

Relapse after allogeneic hematopoietic stem cell transplantation (allo-HSCT) remains the most frequent cause of post-transplantation mortality. Isolated extramedullary (EM) relapse (iEMR) after HSCT is relatively rare and not well characterized, particularly in pediatric patients. We retrospectively analyzed 1527 consecutive pediatric patients with acute leukemia after allo-HSCT to study the incidence, risk factors, and outcome of iEMR compared with systemic relapse.

Treatment and Outcome Analysis of 639 Relapsed Non-Hodgkin Lymphomas in Children and Adolescents and Resulting Treatment Recommendations.

Despite poor survival, controversies remain in the treatment for refractory or relapsed pediatric non-Hodgkin lymphoma (r/r NHL). The current project aimed to collect international experience on the re-induction treatment of r/r NHL, hematopoietic stem cell transplantation (HSCT), risk factors associated with outcome, and to suggest treatment recommendations. Inclusion criteria were (i) refractory disease, disease progression or relapse of any NHL subtype except anaplastic large cell lymphoma, (ii) age < 18 years at initial diagnosis, (iii) diagnosis in/after January 2000.

Allogeneic hematopoietic stem cell transplantation in patients with childhood cerebral adrenoleukodystrophy: A single-center experience "Better prognosis in earlier stage".

Background: ALD is a rare X-linked peroxisomal metabolic disorder with many distinct phenotypes of disease that emerge on a wide scale from adrenal insufficiency to fatal cALD which progresses to a vegetative state within a few years. Currently, HSCT is the only treatment method known to stabilize disease progression in patients with cALD. In this study, we aim to report our HSCT experience in patients with cALD and the factors that determine the success of HSCT, as a single-center experience.

Comparison of Total Body Irradiation-based Versus Chemotherapy-based Conditionings for Early Complications of Allogeneic Hematopoietic Stem Cell Transplantation in Children With ALL.

Background: Total body irradiation (TBI) is the cornerstone of conditioning regimens in pediatric hematopoietic stem cell transplantation for acute lymphoblastic leukemia. As the late effects and survival comparison between TBI and chemotherapy were well analyzed before, in this study, we aim to focus on the first 100 days and early complications of transplantation.

Methods: This retrospective study involves 72 pediatric patients (0 to 18 y) underwent first hematopoietic stem cell transplantation for acute lymphoblastic leukemia between October 2015 and May 2019.

Prognostic factors for survival in children who relapsed after allogeneic hematopoietic stem cell transplantation for acute leukemia.

Background: Post-transplant relapse has a dismal prognosis in children with acute leukemia undergoing allogeneic hematopoietic stem cell transplantation (allo-HSCT). Data on risk factors, treatment options, and outcomes are limited.

Procedure: In this retrospective multicenter study in which a questionnaire was sent to all pediatric transplant centers reporting relapse after allo-HSCT for a cohort of 938 children with acute leukemia, we analyzed 255 children with relapse of acute leukemia after their first allo-HSCT.

Incidence of BKV in the urine and blood samples of pediatric patients undergoing HSCT.

The aims were to investigate the incidence of BKV infection and the presence of HC in pediatric patients undergoing HSCT. Twenty-four children patients (M/F: 17/7) undergoing HSCT in a single center over a period of 1 year were included in the study. The presence of BKV DNA was determined by quantitative real-time PCR in plasma and urine samples at the following times: before transplantation, twice a week until engraftment time, and weekly for + 100 days.

NK-92 cellular therapy for pediatric relapsed/refractory Ewing sarcoma.

Relapsed/refractory Ewing sarcoma prognosis is dreadful, especially for recurrences within the first 2 years after initial diagnosis. It is obvious that there is an urgent need for novel treatment strategies for this dismal situation. NK-92 is an activated NK cell line with high cytotoxicity against malignant cells.

Hematopoietic stem cell transplantation in CD40 ligand deficiency: A single-center experience.

Deficiency of the CD40L, expressed on the surface of T lymphocytes, is caused by mutations in the glycoprotein CD40L (CD154) gene. Resulting defective humoral and cellular responses cause a clinical presentation that includes recurrent sinopulmonary bacterial infections, opportunistic infections, sclerosing cholangitis, neutropenia, and autoimmune manifestations. HSCT represents the only curative treatment modality.

Retrospective Evaluation of Relationship Between Iron Overload and Transplantation Complications in Pediatric Patient Who Underwent Allogeneic Stem Cell Transplantation Due to Acute Leukemia and Myelodysplastic Syndrome.

Background: Hematopoietic stem cell transplantation (HSCT) is a curative therapy option for hematologic malignancies. Iron overload is common in this patient group and can impact short-term and long-term nonrelapse mortality.

Study Design: Retrospective observational cohort study.

Role of a second transplantation for children with acute leukemia following posttransplantation relapse: a study by the Turkish Bone Marrow Transplantation Study Group.

We examined outcomes of 51 pediatric patients with relapsed acute leukemia (AL) who underwent a second allogeneic hematopoietic stem cell transplantation (alloHSCT). After a median follow-up of 941 days (range, 69-2842 days), leukemia-free survival (LFS) and overall survival (OS) at 3 years were 26.6% and 25.

Ruxolitinib salvage therapy is effective for steroid-refractory graft-versus-host disease in children: A single-center experience.

Background: Despite the increasing performance of allogeneic hematopoietic cell transplantation over the last decades, graft-versus-host disease (GVHD) remains the main cause of morbidity and mortality. The efficacy of ruxolitinib against GVHD has been demonstrated in adult studies; however, very few studies have been conducted in children.

Procedure: This study aimed to evaluate the efficacy of ruxolitinib in 29 children with steroid-refractory acute or chronic GVHD.

Haploidentical hematopoietic stem cell transplantation with post-transplant high-dose cyclophosphamide in high-risk children: A single-center study.

Background: Post-Cy administration for GVHD prophylaxis in unmanipulated haploidentical HSCT has resulted in improved outcomes in recent years. Studies in children are lacking and accordingly we present the outcomes of 62 haploidentical transplantation for high-risk children.

Procedure: We retrospectively assessed 62 transplants in 60 patients who underwent haploidentical-related HSCT with unmanipulated stem cells and for whom Post-Cy was used for GVHD prophylaxis.

Risks and outcomes of invasive fungal infections in pediatric allogeneic hematopoietic stem cell transplant recipients receiving fluconazole prophylaxis: a multicenter cohort study by the Turkish Pediatric Bone Marrow Transplantation Study Group.

Invasive fungal infections (IFIs) are a major cause of infection-related morbidity and mortality in patients undergoing allogeneic hematopoietic stem cell transplantation (HSCT). Data from pediatric settings are scarce. To determine the incidence, risk factors and outcomes of IFIs in a 180-day period post-transplantation, 408 pediatric patients who underwent allogeneic HSCT were retrospectively analyzed.

Urgent surgical management of congenital intracranial hemangiopericytoma in a preterm neonate.

Hemangiopericytoma is a rare mesenchymal tumor originating from capillary pericytes, known as Zimmermann pericytes. The adult form is not uncommon and generally malignant but tumor is found rarely in children. Here we describe an intracranial hemangiopericytoma in a preterm newborn whose had the tumor resected successfully shortly after birth.

Immune Reconstitution Inflammatory Syndrome After DLI in a SCID Patient After Hematopoetic Stem Cell Transplantation.

Immune reconstitution inflammatory syndrome (IRIS) is a clinical condition emerging after immune recovery of an immunocompromised status, mostly in human immunodeficiency virus infected patients but also in several other settings, such as the recovery from the severe combined immunodeficiency status after hematopoietic stem cell transplantation. Herein, we report a patient transplanted for severe combined immunodeficiency who developed IRIS for 2 times, namely shortly after transplantation and after donor lymphocyte infusion. Pediatric transplant teams need to be aware of the previous IRIS phenomenon of BCG-adenitis while making the decision of donor lymphocyte infusions.

Treatment of high-risk neuroblastoma: National protocol results of the Turkish Pediatric Oncology Group.

Background: The national protocol aimed to improve the outcome of the high risk neuroblastoma patients by high-dose chemotherapy and stem cell rescue with intensive multimodal therapy.

Materials And Methods: After the 6 induction chemotherapy cycles, patients without disease progression were nonrandomly (by physicians' and/or parent's choices) allocated into two treatment arms, which were designed to continue the conventional chemotherapy (CCT), or myeloablative therapy with autologous stem cell rescue (ASCR).

Results: Fifty-six percent (272 patients) of patients was evaluated as high risk.

Risk factors predicting the survival of pediatric patients with relapsed/refractory non-Hodgkin lymphoma who underwent hematopoietic stem cell transplantation: a retrospective study from the Turkish pediatric bone marrow transplantation registry.

We examined outcomes of 62 pediatric patients with relapsed or refractory non-Hodgkin lymphoma (rr-NHL) who underwent hematopoietic stem cell transplantation (HSCT). The overall survival (OS) and event-free survival (EFS) rates were 65% and 48%, respectively. Survival rates for patients with chemosensitive disease at the time of HSCT were significantly higher than those of patients with chemoresistant disease (69% vs.

Outcomes of high-grade gastrointestinal graft-versus-host disease posthematopoietic stem cell transplantation in children.

We explored the clinical course of acute high-grade gastrointestinal graft-versus-host disease in children in a single center. This was a retrospective analysis of 28 pediatric patients who presented with a clinical diagnosis of stage III and IV acute graft-versus-host disease (aGVHD) of the gastrointestinal system (GIS). Generally, skin involvement was the initial manifestation of aGVHD that began in the first 3 weeks of hematopoietic stem cell transplantation (HSCT); on the other hand, GIS involvement predominated after the second week of HSCT.

Extracorporeal photopheresis did not prevent the development of an autoimmune disease: myasthenia gravis.

Background: Myasthenia gravis (MG) is a neuromuscular disorder characterized by an autoimmune defect in the neuromuscular junction. In most patients, the autoimmune attack is mediated by antibodies against the acetylcholine receptor (AChR) on the postsynaptic membrane. Deficient immunoregulation, including regulatory T cells, is consistently observed.