Juvenile xanthogranuloma manifesting with LCH-associated neurodegenerative disease-like radiological findings.

Here, we describe two patients with juvenile xanthogranuloma (JXG) manifesting with Langerhans cell histiocytosis (LCH)-associated neurodegenerative disease (ND)-like radiological findings. One patient showed typical radiological abnormalities at onset, which worsened with progressing central nervous system symptoms 7 years after LCH-oriented chemotherapy. Another showed spontaneous regression of clinical symptoms, with a transient radiological change 1 year after salvage chemotherapy for recurrence of JXG. These data regarding JXG-associated ND will facilitate future investigation of the disease, as well as development of therapeutic interventions.

Label-free cell detection of acute leukemia using ghost cytometry.

Early diagnosis and prompt initiation of appropriate treatment are critical for improving the prognosis of acute leukemia. Acute leukemia is diagnosed by microscopic morphological examination of bone marrow smears and flow cytometric immunophenotyping of bone marrow cells stained with fluorophore-conjugated antibodies. However, these diagnostic processes require trained professionals and are time and resource-intensive. Here, we present a novel diagnostic approach using ghost cytometry, a recently developed high-content flow cytometric approach, which enables machine vision-based, stain-free, high-speed analysis of cells, leveraging their detailed morphological information. We demonstrate that ghost cytometry can detect leukemic cells from the bone marrow cells of patients diagnosed with acute lymphoblastic leukemia and acute myeloid leukemia without relying on biological staining. The approach presented here holds promise as a precise, simple, swift, and cost-effective diagnostic method for acute leukemia in clinical practice.

Challenges to Widespread Use of Fertility Preservation Facilities for Pediatric Cancer Patients in Japan.

Purpose: Although fertility preservation for pediatric cancer patients is becoming more widespread in Japan, some facilities do not provide sufficient information regarding fertility. This study aimed to elucidate the problems pertaining to the lack of information about fertility among patients. Methods: Based on a 2020 survey, seminars addressing fertility preservation were held from the Designated Pediatric Cancer Care Hospitals in each of the seven blocks in Japan to their partner hospital (pediatric cancer hospitals). The seminar consisted of lectures and group discussions, and a questionnaire was also administered after each seminar. Results: In the group discussions, a lack of explanations to patients and explanatory materials for children were cited as issues by many facilities. The survey results revealed a lack of material explaining fertility preservation and a lack of knowledge among health care providers. There were also many requests to use the patient explanation videos presented at the seminar. Conclusion: The results indicate that further education for health care providers by seminar and other sources and enhancement of explanatory materials are important for fertility preservation in pediatric cancer hospitals in Japan.

RNA-seq-based miRNA signature as an independent predictor of relapse in pediatric B-cell acute lymphoblastic leukemia.

ABSTRACT: Aberrant micro-RNA (miRNA) expression profiles have been associated with disease progression and clinical outcome in pediatric cancers. However, few studies have analyzed genome-wide dysregulation of miRNAs and messenger RNAs (mRNAs) in pediatric B-cell precursor acute lymphoblastic leukemia (BCP-ALL). To identify novel prognostic factors, we comprehensively investigated miRNA and mRNA sequencing (miRNA-seq and mRNA-seq) data in pediatric BCP-ALL samples with poor outcome. We analyzed 180 patients, including 43 matched pairs at diagnosis and relapse. Consensus clustering of miRNA expression data revealed a distinct profile characterized by mainly downregulation of miRNAs (referred to as an miR-low cluster [MLC]). The MLC profile was not associated with any known genetic subgroups. Intriguingly, patients classified as MLC had significantly shorter event-free survival (median 21 vs 33 months; log-rank P = 3 ×10-5). Furthermore, this poor prognosis was retained even in hyperdiploid ALL. This poor prognostic MLC profiling was confirmed in the validation cohort. Notably, non-MLC profiling at diagnosis (n = 9 of 23; Fisher exact test, P = .039) often changed into MLC profiling at relapse for the same patient. Integrated analysis of miRNA-seq and mRNA-seq data revealed that the transcriptional profile of MLC was characterized by enrichment of MYC target and oxidative phosphorylation genes, reduced intron retention, and low expression of DICER1. Thus, our miRNA-mRNA integration approach yielded a truly unbiased molecular stratification of pediatric BCP-ALL cases based on a novel prognostic miRNA signature, which may lead to better clinical outcomes.

Phase 2 study of combination chemotherapy with bortezomib in children with relapsed and refractory acute lymphoblastic leukemia.

Treatment outcomes for children with relapsed and refractory acute lymphoblastic leukemia (R/R-ALL) remain poor, and the optimal induction therapy has not been determined. Bortezomib is a proteasome inhibitor that acts synergistically and additively with standard chemotherapy for ALL. We evaluated the efficacy and safety of combination chemotherapy with bortezomib in children with R/R-ALL. This single-arm, multicenter, phase 2 study was conducted in Japan between 2016 and 2020. Eligible patients were divided into two cohorts: a high-risk first-relapse cohort of untreated patients with high-risk first-relapsed ALL and an expansion cohort of patients with refractory ALL, including multiple relapses, relapse after allogeneic hematopoietic cell transplantation, and induction failure. All patients received a single course of chemotherapy as induction therapy. Sixteen patients (10 in the high-risk first-relapse cohort, six in the expansion cohort) were evaluable. The overall remission rate after induction therapy was 60% in the high-risk first-relapse cohort and 16.7% in the expansion cohort. All patients had minimal residual disease. Adverse events were acceptable except for interstitial lung disease and hypoxia in a patient in the expansion cohort, but addition of bortezomib to conventional chemotherapy did not produce obvious improvement in children with R/R-ALL.

Current status of CAR-T cell therapy for pediatric hematologic malignancies.

Acute lymphoblastic leukemia (ALL) is the most common cancer in the pediatric population, and the long-term survival can reach 90%. However, approximately, 20% of pediatric ALL patients experience relapse and require second-line chemotherapy. This is frequently followed by hematopoietic stem cell transplantation, which can cause long-term sequelae. Recent advances in immunotherapy, such as monoclonal antibody therapy and chimeric antigen receptor (CAR)-T cell therapy, have revolutionized the treatment of relapsed and refractory ALL. Anti-CD19 CAR-T cells successfully eliminate B cell malignancies such as ALL. Tisagenlecleucel (Kymriah®) is the first CAR-T cell immunotherapy approved by the FDA. CAR-T cell therapy can cause specific adverse events (AEs) such as cytokine release syndrome and immune effector cell-associated neurotoxicity syndrome, which are defined and graded according to the consensus grading system and treated with supportive therapies along with tocilizumab and corticosteroids. Other AEs include prolonged bone marrow suppression and hypogammaglobulinemia. Severe AEs are less common in the real-world experience than in clinical trials, probably due to better management of the patient before and during CAR-T cell therapy. The biggest challenge in CAR-T cell therapy against ALL is relapse. A high tumor burden on infusion, early loss of B cell aplasia, and minimal residual disease positivity after CAR-T cell infusion are predictive of relapse. Consolidative stem cell transplantation may improve the long-term outcome. The success of CD19 CAR-T cell therapy against B cell malignancy prompted extensive research into the use of CAR-T cells against other hematologic malignancies such as T cell leukemia or myeloid leukemia.

The first successful case of ABO-incompatible living-donor lobar lung transplantation following desensitization therapy.

ABO-incompatible (ABO-I) living-donor lobar lung transplantation (LDLLT) was successfully performed in a 14-year-old girl who suffered from bronchiolitis obliterans due to graft-versus-host disease following hematopoietic stem cell transplantation. In the ABO-I LDLLT procedure, the blood type O patient received a right lower lobe donated from her blood type B father and a left lower lobe donated from her blood type O mother. Desensitization therapy, using rituximab, immunosuppressants, and plasmapheresis, was implemented for 3 weeks prior to transplantation to reduce the production of anti-B antibodies in the recipient and prevent acute antibody-mediated rejection after ABO-I LDLLT.

High-dose carboplatin-irinotecan-temozolomide is an effective salvage chemotherapy for relapsed or refractory neuroblastoma.

There is no clear consensus on the most effective treatment for relapsed/refractory high-risk neuroblastoma (NB). We retrospectively assessed seven NB patients with relapsed/refractory disease who received high-dose carboplatin-irinotecan-temozolomide (HD-CIT). Five of seven patients showed favorable therapeutic response (complete remission or partial remission). Regarding toxicity, the cytopenia period tended to prolong when more than three cycles were repeated, but nonhematological toxicities were controllable with general supportive care. Due to its antitumor efficacy and well-tolerated nonhematologic toxicity, HD-CIT is a promising salvage chemotherapy for relapsed/refractory NB. However, it is important to pay attention to the exacerbation of hematological toxicity when repeating the regimen.

Safety and efficacy of post-haematopoietic cell transplantation maintenance therapy with blinatumomab for relapsed/refractory CD19-positive B-cell acute lymphoblastic leukaemia: protocol for a phase I-II, multicentre, non-blinded, non-controlled trial (JPLSG SCT-ALL-BLIN21).

INTRODUCTION: Relapsed and refractory B-cell acute lymphoblastic leukaemia (R/R-B-ALL) is linked to a significant relapse rate after allogeneic haematopoietic cell transplantation (allo-HCT) in children, adolescents and young adults (CAYA). No standard treatment has been established to prevent relapse after allo-HCT for R/R-B-ALL, which is an unmet medical need. The administration of blinatumomab after allo-HCT is expected to enhance the antileukaemic effect on residual CD19-positive blasts by donor-derived CD3-positive T-cells. METHODS AND ANALYSIS: The goal of this multicentre, open-label, uncontrolled, phase I-II clinical trial is to assess the safety and effectiveness of post-transplant maintenance therapy with blinatumomab for CAYA patients (25 years old or younger) with CD19-positive R/R-B-ALL who have received allo-HCT beyond first complete remission (CR) and have CR with haematological recovery between 30 and 100 days after allo-HCT. Eighty-five paediatric institutions in Japan are participating in this study. Forty-one patients will enrol within 2.25-year enrolment period and follow-up period is 1 year. The primary endpoints are the treatment completion rate for phase I study and the 1-year graft-versus-host disease-free/relapse-free survival rate for phase II study, respectively. ETHICS AND DISSEMINATION: This research was approved by the Central Review Board at National Hospital Organization Nagoya Medical Center (Nagoya, Japan) on 21 January 2022 and was registered at the Japan Registry of Clinical Trials (jRCT) on 3 March 2022. Written informed consent is obtained from all patients and/or their guardians. The results of this study will be disseminated through peer-reviewed publications and conference presentations. TRIAL REGISTRATION NUMBER: jRCTs041210154.

Three-Year Update of Tisagenlecleucel in Pediatric and Young Adult Patients With Relapsed/Refractory Acute Lymphoblastic Leukemia in the ELIANA Trial.

Clinical trials frequently include multiple end points that mature at different times. The initial report, typically based on the primary end point, may be published when key planned co-primary or secondary analyses are not yet available. Clinical Trial Updates provide an opportunity to disseminate additional results from studies, published in JCO or elsewhere, for which the primary end point has already been reported.In the primary analysis of the global phase II ELIANA trial (ClinicalTrials.gov identifier: NCT02435849), tisagenlecleucel provided an overall remission rate of 81% in pediatric and young adult patients with relapsed or refractory B-cell acute lymphoblastic leukemia (R/R B-ALL), with 59% of responders remaining relapse-free at 12 months. Here, we report an update on efficacy, safety, and patient-reported quality of life in 79 pediatric and young adult patients with R/R B-ALL following a median follow-up of 38.8 months. The overall remission rate was 82%. The median event-free survival was 24 months, and the median overall survival was not reached. Event-free survival was 44% (95% CI, 31 to 57) and overall survival was 63% (95% CI, 51 to 73) at 3 years overall (most events occur within the first 2 years). The estimated 3-year relapse-free survival with and without censoring for subsequent therapy was 52% (95% CI, 37 to 66) and 48% (95% CI, 34 to 60), respectively. No new or unexpected long-term adverse events were reported. Grade 3/4 adverse events were reported in 29% of patients > 1 year after infusion; grade 3/4 infection rate did not increase > 1 year after infusion. Patients reported improvements in quality of life up to 36 months after infusion. These findings demonstrate favorable long-term safety and suggest tisagenlecleucel as a curative treatment option for heavily pretreated pediatric and young adult patients with R/R B-ALL.

Outcome and growth of lobar graft after pediatric living-donor lobar lung transplantation.

BACKGROUND: Living-donor lobar lung transplantation (LDLLT) remains a life-saving option for pediatric patients with respiratory failure. However, the long-term survival and post-transplant quality of adult lobar grafts transplanted into children are unknown. Therefore, this study aimed to evaluate the outcomes of pediatric LDLLT and post-transplant graft growth. METHODS: We retrospectively reviewed the prospectively collected clinical data of 25 living-donor lung transplantations performed in 24 pediatric recipients aged ≤17 years. The annual pulmonary function test data and computed tomography scans of 12 recipients, followed up for >5 years without significant complications, were used to evaluate growth in height, graft function, and radiological changes. The Kaplan-Meier method and simple linear regression were performed for analysis. RESULTS: Bilateral lower lobe transplantation was performed in 12 patients, unilateral lower lobe transplantation in 12, and bilateral middle lobe transplantation in 1. The median volumetric size matching at transplantation was 142% (range, 54%-457%). The 5- and 10-year overall survival rates were 87.7% and 75.1༅, respectively. Chronic lung allograft dysfunction occurred in 2 patients. During a median follow-up of 6 years, the median increases in height and vital capacity were 14.4% (range, 0.80%-43.5%) and 58.5% (range, 6.7%-322%), respectively. Graft weight was positively correlated with graft volume (r2=0.622, p<0.001) after the graft volume exceeded the original lobar volume in the donor. CONCLUSIONS: This study shows that pediatric LDLLT offers satisfactory long-term survival, with the growth of mature adult lobes transplanted into growing children.

Autologous Recovery With Chromosomal Abnormalities After Unrelated Umbilical Cord Blood Transplantation With Myeloablative Conditioning in a Case of Pediatric Acute Lymphoblastic Leukemia.

Detailed case reports of autologous recovery of hematopoiesis after hematopoietic stem cell transplantation with myeloablative conditioning are scarce. We present a rare case of a 3-year-old male with relapsed KMT2A -rearranged acute lymphoblastic leukemia who experienced autologous recovery following secondary engraftment failure after cord blood transplantation with myeloablative conditioning. Similar to prior reports, we detected unusual chromosomal abnormalities, which differed at each bone marrow examination. He remains alive without relapse of acute lymphoblastic leukemia 8 months after cord blood transplantation. As the rate of recurrence or late occurrence of secondary malignant neoplasm remains unclear, careful follow-up is required, especially in pediatric patients.

Use of Cabozantinib to Treat MET -amplified Pediatric Colorectal Cancer.

Pediatric colorectal cancer (CRC) is extremely rare, with little information about genetic profiles compared with adult CRC. Here, a 13-year-old male with advanced CRC underwent cancer gene panel testing, which detected 4 genetic abnormalities ( MET amplification in addition to TP53 , SMAD4 , and CTNNA1 mutations) that might be associated with a poor prognosis. Based on high-level MET amplification, he received a multikinase inhibitor, cabozantinib, after failure of first-line and second-line chemotherapy, resulting in transient disease stabilization. Tailored targeted therapy based on molecular profiling can be an effective treatment strategy for rare cancers such as pediatric CRC.

Living-donor segmental lung transplantation for pediatric patients.

OBJECTIVE: The preset study evaluated the outcome of living-donor segmental lung transplantation for pediatric patients. METHODS: Between August 2009 and May 2021, we performed living-donor segmental lung transplantation in 6 critically ill pediatric patients, including 1 patient on a ventilator alone and another patient on a ventilator and extracorporeal membrane oxygenation (ECMO). There were 4 male and 2 female patients, with a median age of 7 years (range, 4-15 years) and a median height of 112.7 cm (range, 95-125.2 cm). The diagnoses included complications of allogeneic hematopoietic stem cell transplantation (n = 4) and pulmonary fibrosis (n = 2). All patients received bilateral lung transplantation under cardiopulmonary bypass. A basal segment and a lower lobe were implanted in 3 patients, and a basal segment and an S6 segment were implanted in the other 3 patients. In 2 patients, the right S6 segmental graft was horizontally rotated 180° and implanted as the left lung. RESULTS: Among the 9 segmental grafts implanted, 7 functioned well after reperfusion. Two rotated S6 segmental grafts became congestive, with 1 requiring graft extraction and the other venous repair, which was successful. There was 1 hospital death (14 days) due to sepsis and 1 late death (9 years) due to leukoencephalopathy. The remaining 4 patients are currently alive at 9 months, 10 months, 1.3 years, and 1.9 years. CONCLUSIONS: Living-donor segmental lung transplantation was a technically difficult but feasible procedure with acceptable outcomes for small pediatric patients with chest cavities that were too small for adult lower lobe implantation.

Clinical Outcomes of Patients With Osteosarcoma Experiencing Relapse or Progression: A Single-institute Experience.

BACKGROUND: Patients with osteosarcoma who experience relapse or progression [R/P] have a poor prognosis. METHODS: Data from 30 patients who experienced R/P among 59 with a diagnosis of high-grade osteosarcoma, who were younger than 40 years old between 2000 and 2019, were retrospectively analyzed to identify prognostic and therapeutic factors influencing their outcomes. RESULTS: The 5-year overall survival [OS] rates after the last R/P of patients experiencing first [n=30], second [n=14], and third [n=9] R/P were 50.3%, 51.3%, and 46.7%, respectively. Multivariate analysis did not identify any independent risk factors affecting OS. The 5-year PFS rate of the 30 patients after first R/P was 22.4%, and multivariate analysis identified histologic subtype and curative local surgery as independent risk factors influencing PFS. Long [>6 mo] partial response was observed in three patients treated using temozolomide+etoposide, irinotecan+carboplatin, or regorafenib. CONCLUSIONS: OS rate in the patients with osteosarcoma experiencing R/P included in this study was markedly higher than that reported previously, mainly due to the surgical total removal of tumors, even after subsequent R/P. The recent establishment of salvage chemotherapy or molecular targeted therapy may also increase survival rates in a subgroup of patients.

RUNX1-Survivin Axis Is a Novel Therapeutic Target for Malignant Rhabdoid Tumors.

Malignant rhabdoid tumor (MRT) is a highly aggressive pediatric malignancy with no effective therapy. Therefore, it is necessary to identify a target for the development of novel molecule-targeting therapeutic agents. In this study, we report the importance of the runt-related transcription factor 1 (RUNX1) and RUNX1-Baculoviral IAP (inhibitor of apoptosis) Repeat-Containing 5 (BIRC5/survivin) axis in the proliferation of MRT cells, as it can be used as an ideal target for anti-tumor strategies. The mechanism of this reaction can be explained by the interaction of RUNX1 with the RUNX1-binding DNA sequence located in the survivin promoter and its positive regulation. Specific knockdown of RUNX1 led to decreased expression of survivin, which subsequently suppressed the proliferation of MRT cells in vitro and in vivo. We also found that our novel RUNX inhibitor, Chb-M, which switches off RUNX1 using alkylating agent-conjugated pyrrole-imidazole polyamides designed to specifically bind to consensus RUNX-binding sequences (5'-TGTGGT-3'), inhibited survivin expression in vivo. Taken together, we identified a novel interaction between RUNX1 and survivin in MRT. Therefore the negative regulation of RUNX1 activity may be a novel strategy for MRT treatment.