Alectinib maintenance therapy following cord blood transplantation for relapsed pediatric anaplastic large cell lymphoma with central nervous system involvement.

Pediatric ALK-positive anaplastic large cell lymphoma is a rare subtype of non-Hodgkin lymphoma, and approximately 30% of patients relapse following treatment with conventional chemotherapy. Alectinib monotherapy has demonstrated excellent activity in relapsed and refractory ALCL, but its role as a maintenance therapy after hematopoietic cell transplantation is unclear. We experienced a relapse case of pediatric ALK-positive ALCL with central nervous system involvement treated with alectinib maintenance therapy following cord blood transplantation.

Delayed diagnostic interval and survival outcomes in pediatric leukemia: A single-center, retrospective study.

Objective: This study primarily focused on the diagnostic interval (DI), defined as the duration from the onset of leukemic symptoms to diagnosis. We investigated whether a prolonged DI is associated with the outcomes of pediatric leukemia.

Methods: We retrospectively collected data of children with newly diagnosed pediatric leukemia at Okayama University Hospital from January 2007 to December 2022.

Three Cases of Down Syndrome with Transient Abnormal Myelopoiesis who Underwent Liver Biopsy before Induction of Low-Dose Cytarabine.

Among patients with transient abnormal myelopoiesis (TAM) associated with Down syndrome, approximately 20% die within 6 months from multiorgan failure, especially liver fibrosis. We experienced three children with TAM who had low white blood cell counts but increased bilirubin levels. Here, we discuss the detailed clinical courses of these patients, including the pathological findings of liver biopsies.

Low-dose acyclovir for prophylaxis of varicella-zoster virus reactivation after hematopoietic stem cell transplantation in children.

Background: Varicella-zoster virus (VZV) reactivation is a serious complication of hematopoietic stem cell transplantation (HSCT). Although low-dose acyclovir can prevent VZV reactivation after HSCT in adults, the efficacy of a dose of acyclovir lower than the recommended dose, such as 60-80 mg/kg/day in children, is unclear. In this study, we aimed to evaluate the incidence of VZV reactivation after HSCT during and after low-dose acyclovir administration for preventing VZV reactivation in children.

Delayed Methotrexate Elimination after Administration of a Medium Dose of Methotrexate in a Patient with Genetic Variants Associated with Methotrexate Clearance.

Polymorphisms in methotrexate transporter pathways have been associated with methotrexate toxicities and clearance. Recent genome-wide association studies have revealed that the SLCO1B1 T521C variant is associated with methotrexate elimination. We present a case of a pediatric patient with acute lymphoblastic leukemia who suffered from persistently high plasma methotrexate concentrations and acute kidney injuries after the admin-istration of a medium dose of methotrexate.

Clinical Factors Affecting the Dose Conversion Ratio from Intravenous to Oral Tacrolimus Formulation among Pediatric Hematopoietic Stem Cell Transplantation Recipients.

Background: Tacrolimus is converted from intravenous to oral formulation for the prophylaxis of graft-versus-host disease when patients can tolerate oral intake and graft-versus-host disease is under control. Oral tacrolimus formulation presents poor bioavailability with intraindividual and interindividual variations; however, some factors affecting its blood concentration among pediatric hematopoietic stem cell transplantation (HCT) recipients are still unclear. This study aimed to identify the clinical factors affecting tacrolimus blood concentrations after switching its formulation.

[Prognostic significance of chimeric fusion gene analysis in pediatric acute megakaryoblastic leukemia].

Acute megakaryoblastic leukemia in children without Down syndrome (non-DS AMKL) is considered to be a poor prognostic subtype in acute myeloid leukemia. Recently, some chimeric fusion genes were found in pediatric non-DS AMKL; therefore, we attempted to detect chimeric fusion genes RBM15-MKL1, CBFA2T3-GLIS2, and NUP98-KDM5A from 10 pediatric non-DS AMKL diagnostic samples using polymerase chain reaction and Sanger sequencing methods. Two samples were positive for RBM15-MKL1, four had CBFA2T3-GLIS2, and only one case had NUP98-KDM5A.

Panel-based next-generation sequencing identifies prognostic and actionable genes in childhood acute lymphoblastic leukemia and is suitable for clinical sequencing.

Acute lymphoblastic leukemia (ALL) is the most common malignancy in children. Although the cure rate of ALL has greatly improved, a considerable number of patients suffer from relapse of leukemia. Therefore, ALL remains the leading cause of death from cancer during childhood.

Long-term Remission of Hepatitis-associated Aplastic Anemia Possibly due to Immunosuppressive Therapy after Liver Transplantation.

Hepatitis-associated aplastic anemia (HAAA) is an acquired bone marrow failure syndrome that develops after seronegative fulminant hepatitis. Abnormal cytotoxic T-cell activation with cytokine release is a possible pathophysiology. We present the case of a 16-month-old Japanese male who developed HAAA following living-donor liver transplantation for fulminant hepatitis.

Sorafenib treatment for papillary thyroid carcinoma with diffuse lung metastases in a child with autism spectrum disorder: a case report.

Background: Pediatric papillary thyroid carcinoma frequently presents with lymph node involvement and distant metastases. Sorafenib, an oral multikinase inhibitor, has been used to treat radioactive iodine (RAI) therapy-refractory thyroid carcinoma in adults; however, pediatric experience is limited. Medical procedures and hospitalization for children with autism spectrum disorder may be challenging.

A Case of Refractory Langerhans Cell Histiocytosis Complicated with Hemophagocytic Lymphohistiocytosis Rescued by Cord Blood Transplantation with Reduced-intensity Conditioning.

　We diagnosed a female infant with Langerhans cell histiocytosis (LCH) who was refractory to conventional chemotherapy. She showed refractory inflammation that was complicated with hemophagocytic lymphohistiocytosis (HLH) during LCH chemotherapy; therefore, we changed the protocol to HLH2004 (dexamethasone, cyclosporine A and VP16). However, there were no signs of hematological recovery.

Desmoid-type fibromatosis in a boy with Down syndrome.

Patients with Down syndrome (DS) have a markedly higher incidence of childhood leukemia, but a lower incidence of most solid tumors, compared with age-matched euploid individuals. Trisomy 21 might be protective against tumorigenesis because of several tumor suppressive mechanisms. Desmoid-type fibromatosis (DF) is a rare monoclonal, fibroblastic proliferation characterized by a variable clinical course.

Two Relapsed Stage III Childhood Anaplastic Large Cell Lymphoma Patients with NPM-ALK Fusion in Bone Marrow from Initial Diagnosis.

Childhood anaplastic large cell lymphoma (ALCL) accounts for approx. 10-30% of cases of non-Hodgkin lymphoma, and the ALCL99 study reported 60-75 disease-free survival; however, a relatively high relapse rate was observed (25-30% ). We report 2 patients with Stage III ALCL who relapsed 6-18 months after the end of ALCL99 chemotherapy.

Pediatric intestinal Behçet disease complicated by myeloid malignancies.

Behçet disease (BD) is rarely seen in children. Its clinical manifestations are believed to differ between pediatric and adult patients. The characteristics of BD complicated by myelodysplastic syndrome (MDS) are well established for adult patients; however, because only a few cases of pediatric-onset BD complicated by MDS have been reported, its clinical characteristics remain unknown.

Adults with germline CBL mutation complicated with juvenile myelomonocytic leukemia at infancy.

Juvenile myelomonocytic leukemia (JMML) appears to be a life-threatening disease and showed poor prognosis even after hematopoietic stem cell transplantation (HSCT) because of high relapse rate. On the other hand, recent molecular analysis revealed the heterogeneity of JMML. Here we report that two JMML patients survived >20 years without HSCT and both patients had uniparental disomy of 11q23 where CBL is located without the phenomenon found in neither Noonan syndrome nor Noonan syndrome-like disorder.

A Long-term Survivor after Congenital Acute Myeloid Leukemia with t(8 ; 16)(p11 ; p13).

The treatment of patients with congenital leukemia is difficult and often results in a poor prognosis. We present here the case of a female child with congenital acute myeloid leukemia (AML) with t(8 ; 16) (p11 ; p13) who received chemotherapy and survived for more than 10 years without relapse. A novel MOZ-CBP chimera was found in her diagnostic sample.

Verification of risk scores to predict i.v. immunoglobulin resistance in incomplete Kawasaki disease.

Background: A recent study indicated the efficacy of the addition of prednisolone to i.v. immunoglobulin (IVIG) as initial treatment in patients with higher risk of IVIG resistance.

Transient myeloproliferative disorder with partial trisomy 21.

Myeloid malignancy with Down syndrome (ML-DS) is estimated to have a step-wise leukemogenesis including GATA1 mutation. Trisomy 21 is essential for ML-DS; however, we do not know exactly which gene or genes located on chromosome 21 are necessary for the ML-DS. We report a female infant with transient myeloproliferative disorder (TMD) and partial trisomy 21.