Feasibility of 18F-DOPA and 18F-FDG PET/CT for guiding decision-making for localized incidental neuroblastoma in infants under 18 months of age.

BACKGROUND: Neuroblastoma varies widely in risk. Risk indicators in infants with incidental neuroblastoma refine treatment confidence for observation or intervention. The potential of functional imaging, particularly PET/CT, remains to be defined. PROCEDURE: A retrospective review of infants under 18 months diagnosed with incidental neuroblastoma from 2008 to May 2022 in our institute was conducted. Before October 2015, incidental patients were treated similarly to symptomatic cases, undergoing biopsy or surgical excision upon diagnosis (early cohort). Post October 2015 (late cohort), treatment decisions were guided by PET/CT findings, with 18F-DOPA PET/CT confirming diagnosis and staging. For tumors with low 18F-FDG uptake, an expectant observation approach was considered. Patient characteristics, diagnostic methods, image findings at diagnosis, treatment courses, and responses were compared between cohorts. RESULTS: Thirty infants less than 18 months were identified with incidental neuroblastoma and completed PET/CT at diagnosis. The early and late cohorts each comprised 15 patients. In the late cohort, nine out of 15 patients (60%) presented with localized FDG non-avid tumors were offered the option of expectant observation. Of these, seven patients opted for observation, thereby avoiding surgery. Treatment outcomes were comparable between early and late cohorts, except for one mortality of a patient who, despite showing 18F-FDG activity, declined treatment. CONCLUSIONS: This study demonstrates the potential utility of 18F-DOPA and 18F-FDG PET/CT scans in aiding clinical decision-making for infants with localized, incidental neuroblastoma. Given the concerns regarding radiation exposure, such imaging may be valuable for cases with suspected metastasis, initial large tumor size, or growth during follow-up.

Higher tumor mutational burden is associated with inferior outcomes among pediatric patients with neuroblastoma.

INTRODUCTION: Neuroblastoma is a pediatric malignancy with heterogeneous clinical outcomes. Our aim was to identify prognostic genetic markers for patients with neuroblastoma, who were treated with the Taiwan Pediatric Oncology Group (TPOG) neuroblastoma N2002 protocol, to improve risk stratification and inform treatment. METHODS: Our analysis was based on 53 primary neuroblastoma specimens, diagnosed pre-chemotherapy, and 11 paired tumor relapse specimens. Deep sequencing of 113 target genes was performed using a custom panel. Multiplex ligation-dependent probe amplification was performed to identify clinical outcomes related to copy-number variations. RESULTS: We identified 128 variations associated with survival, with the number of variations being higher in the relapse than that in the diagnostic specimen (p = .03). The risk of event and mortality was higher among patients with a tumor mutational burden ≥10 than that in patients with a lower burden (p < .0001). Multivariate analysis identified tumor mutational burden, MYCN amplification, and chromosome 3p deletion as significant prognostic factors, independent of age at diagnosis, sex, and tumor stage. The 5-year event-free survival and overall survival rate was lower among patients with high tumor burden than in patients with low tumor burden. Furthermore, there was no survival of patients with an ALK F1147L variation at 5 years after diagnosis. CONCLUSIONS: Genome sequencing to determine the tumor mutational burden and ALK variations can improve the risk classification of neuroblastoma and inform treatment.

Clinical impact of minimal residual disease and genetic subtypes on the prognosis of childhood acute lymphoblastic leukemia.

BACKGROUND: This study analyzed data from two consecutive protocols for children newly diagnosed with acute lymphoblastic leukemia (ALL) to determine the clinical impact of minimal/measurable residual disease (MRD) and recently identified tumor genetic subtypes. METHODS: Genetic subtypes were determined by sequential approaches including DNA indexing, reverse transcriptase-polymerase chain reaction, multiplex ligation-dependent probe amplification, and RNA-sequencing. MRD was assessed by flow cytometry. The Taiwan Pediatric Oncology Group TPOG-ALL-2013 study enrolled patients who received MRD-directed therapy. RESULTS: The 5-year event-free survival (EFS) and overall survival rates in the 2013 cohort were 77.8% and 86.9% compared to those of the 2002 cohort, which were 62.4% and 76.5%. Among patients treated with MRD-guided therapy, those with ETV6-RUNX1 fusion and high hyperdiploidy had the highest 5-year EFS (91.4% and 89.6%, respectively). The addition of dasatinib improved outcomes in patients with BCR-ABL1 ALL. Recently identified subtypes like DUX4-rearranged, ZNF384-rearranged, MEF2D-rearranged, and PAX5alt subtypes were frequently positive for MRD after remission induction, and these patients consequently received intensified chemotherapy. Treatment intensification according to the MRD improved the outcomes of patients presenting DUX4 rearrangements. In high-risk or very-high-risk subtypes, the TPOG-ALL-2013 regimen did not confer significant improvements compared to TPOG-ALL-2002, and the outcomes of BCR-ABL1-like, MEF2D-rearranged, and KMT2A-rearranged ALL subtypes (in addition to those of T-cell ALL) were not sufficiently good. Novel agents or approaches are needed to improve the outcomes for these patients. CONCLUSIONS: The TPOG-ALL-2013 study yielded outcomes superior to those of patients treated in the preceding TPOG-ALL-2002 study. This study provides important data to inform the design of future clinical trials in Taiwan. PLAIN LANGUAGE SUMMARY: MRD-directed therapy improved the outcomes for pediatric ALL, especially standard-risk patients. Genomic analyses and MRD might be used together for risk-directed therapy of childhood ALL. Our work provides important data to inform the design of future clinical trials in Taiwan.

High frequency of heat shock protein 27 overexpression is a highly effective, high-coverage marker for minimal residual disease detection in children with B-cell acute lymphoblastic leukemia.

BACKGROUND: Acute lymphoblastic leukemia (ALL) is the most common pediatric cancer. Minimal residual disease (MRD) detection is the most powerful prognostic tool for monitoring treatment efficacy and predicting clinical outcomes. We aimed to identify key leukemia-associated markers, the proportions of differential expression in patients, and the most effective marker combination for MRD detection by flow cytometry. METHODS: Bone marrow samples were collected from 132 pediatric patients with newly diagnosed (n = 115) or relapsed (n = 17) B-cell precursor (BCP)-ALL. We used CD19, CD10, CD34, CD45 as backbone markers to identify immature B cells and analyzed the differential expression of 18 leukemia-associated markers using seven-color multiparameter flow cytometry. RESULTS: Leukemic cells in all 132 patients expressed leukemia-associated markers. The most commonly overexpressed marker was heat shock protein 27 (Hsp27) (108 patients, 81%), followed by CD73 (102 patients, 77%) and CD123 (80 patients, 60%). CD38 was underexpressed in 64 patients (48%). Hsp27 overexpression persisted in 50 out of 57 follow-up MRD bone marrow samples (87%) and was associated with older age at diagnosis. Hsp27 overexpression was not associated with MRD levels or genetic abnormalities including hyperdiploidy, t(12;21)/ETV6-RUNX1, t(1;19)/TCF3-PBX1, t(9;22)/BCR-ABL1, or 11q23/KMT2A rearrangements. Four remaining leukemia-associated markers (Hsp27, CD73, CD58, CD24) after in silico deletion from the original panel could collectively detect leukemia-associated cell profiles in 100% of cases in this cohort and 98% of cases in a validation cohort. CONCLUSION: Hsp27 combined with CD73, CD58, CD24, and backbone markers allows monitoring MRD in virtually all patients with BCP-ALL.

Acute pancreatitis in children with acute lymphoblastic leukemia correlates with L-asparaginase dose intensity.

BACKGROUND: L-Asparaginase (L-Asp) is an important therapeutic for childhood acute lymphoblastic leukemia (ALL). Asparaginase-associated pancreatitis (AAP) is a severe complication of L-Asp related to the dosage. We investigated the incidence of, and risk factors for, AAP in pediatric patients with ALL. METHODS: From January 2002 to December 2018, pediatric patients with ALL treated at National Taiwan University Hospital were enrolled in this study. The diagnosis of AAP was based on the criteria of the Ponte di Legno Toxicity Working Group. RESULTS: Of the 353 patients enrolled in this study, 14 (4.0%) developed AAP. The incidence of AAP in ALL patients was significantly higher after treatment with the 2013 protocol compared with the 2002 protocol of the Taiwan Pediatric Oncology Group (9.5% vs. 1.3%). Multivariate analysis showed that a high peak L-Asp dose intensity (>45,000 U/m2/month) and older age at diagnosis (>6.8 years) were independently predictive of AAP development. CONCLUSIONS: The incidence of acute pancreatitis in childhood ALL was correlated more strongly with the peak dose intensity than with the cumulative dose of L-Asp. These results could be used to reduce the treatment-related complications of ALL. IMPACT: L-Asparaginase is an important therapeutic for childhood acute lymphoblastic leukemia, and the accumulated dosage of L-asparaginase is considered as a major risk factor of asparaginase-associated pancreatitis. This article demonstrated that the incidence of pancreatitis correlates with the dose-intensity of L-asparaginase, but not the accumulated dosage. Identification of patient group with high risk of pancreatitis could lead to early diagnosis and reduce the complication. This finding could aid in developing further new protocol or therapeutic strategy design to reduce treatment-related complications and improve clinical outcomes of childhood acute lymphoblastic leukemia.

Integration of immunohistochemistry, RNA sequencing, and multiplex ligation-dependent probe amplification for molecular classification of pediatric medulloblastoma.

BACKGROUND: Medulloblastoma (MB) is commonly classified into four molecular groups, that is, WNT, SHH, group 3, and group 4, for prognostic and therapeutic purposes. METHODS: Here we applied immunohistochemistry (IHC) and RNA sequencing (RNA-seq) for the molecular classification of MB, and utilized multiplex ligation-dependent probe amplification (MLPA) to determine chromosomal alterations and specific gene amplifications. RESULTS: We retrospectively enrolled 37 pediatric MB patients. Twenty-three had genomic material available for gene/RNA analysis. For IHC, ß-catenin, GAB1, and YAP were the biomarkers to segregate MB into three subgroups, WNT (1/23), SHH (5/23), and non-WNT/non-SHH (17/23). However, four cases (17.3%) were found to be misclassified after analysis by RNA-seq. The result of MLPA revealed two group 3 tumors carrying MYC amplification, and three SHH tumors harboring MYCN amplification. While IHC provided rapid subgroup stratification, it might result in incorrect subgrouping. Thus, validation of the IHC result with genomic data analysis by RNA-seq or other tools would be preferred. In addition, MLPA can detect important genetic alterations and is helpful for the identifications of high-risk patients. CONCLUSIONS: Our study revealed that integration of these diagnostic tools can provide a precise and timely classification of MB, optimizing an individualized, risk-directed postoperative adjuvant therapy for these patients. This workflow can be applied in a countrywide fashion to guide future clinical trials for patients with MB.

A child with juvenile myelomonocytic leukemia possessing a concurrent germline CBL mutation and a NF1 variant of uncertain significance: A rare case with a common problem in the era of high-throughput sequencing.

Genetic changes in juvenile myelomonocytic leukemia (JMML) determine distinct subtypes, treatments, and outcomes. JMML with germline CBL mutation and somatic NRAS mutation possibly achieves spontaneous remission, but hematopoietic stem cell transplantation is indicated for other subtypes of JMML. We hereby report a child with JMML harboring a germline CBL mutation (c.1111T>C) and an NF1 variant (c.3352A>G) concurrently. After evaluation, we considered that the NF1 variant was not the major contributor. After one year of observation, this case had no signs of disease progression. This case highlights the importance of combining available evidence and clinical findings in caring for patients with unusual genomic variations.

Outcomes and prognostic factors associated with 180-day mortality in Taiwanese pediatric patients with Hemophagocytic Lymphohistiocytosis.

BACKGROUND/PURPOSE: Hemophagocytic lymphohistiocytosis (HLH), a rarely occurring syndrome with various triggers, is associated with early mortality. Owing to a lack of sufficient corresponding data in Taiwan, this study aimed to identify the outcome and potential factors associated with 180-day mortality in pediatric HLH. METHODS: This retrospective study analyzed clinical and laboratory data on pediatric patients diagnosed with HLH at our institute (1995-2019). Logistic regression analysis was conducted to determine the associations between various factors and 180-day mortality. RESULTS: Overall, 48 patients had HLH; their median age at diagnosis was 5 years (interquartile range: 2-11 years). Clinical presentations and laboratory parameters required for diagnosis included fever (98%), splenomegaly (79%), hyperferritinemia (98%), hemophagocytosis (94%), thrombocytopenia (90%), anemia (63%), hypertriglyceridemia (68%), and neutropenia (57%). The 5-year overall survival (OS) rate was 49%. Of 22 patients who had died at the last follow-up, 15 (68%) died within 180 days after diagnosis. In the multivariate analysis, hemoglobin (odds ratio [OR]: 0.564, p = 0.024) and triglyceride (OR: 1.004, p = 0.049) were significantly associated with 180-day mortality. Higher triglyceride levels at diagnosis were related to significantly lower 180-day OS rates (52.9% vs. 86.1%, p = 0.018). CONCLUSION: The overall outcome in our cohort was similar to that reported in some of the largest international cohorts. Hypertriglyceridemia and anemia may be indicative of poor prognoses in pediatric HLH patients independently and may be used to guide treatment strategy formulations for better outcomes.

MYCN RNA levels determined by quantitative in situ hybridization is better than MYCN gene dosages in predicting the prognosis of neuroblastoma patients.

The aim of this study was to investigate the prognostic role of MYCN RNA expression by quantitative RNA in situ hybridization and its association with MYCN amplification in neuroblastoma. MYCN RNA expression in 69 neuroblastoma tumors was evaluated by an ultrasensitive quantitative RNA in situ hybridization technique, RNAscope. The correlations between MYCN RNA expression, MYCN amplification, and other clinicopathologic variables of neuroblastoma were analyzed. High expression levels of MYCN RNA were detected 30 of 69 (43%) of neuroblastomas, mainly in those with undifferentiated or poorly differentiated histology. High expression of MYCN RNA was significantly associated with MYCN amplification (P < 0.001) and other adversely prognostic factors, including older age at diagnosis (>18 months, P = 0.017), advanced clinical stage (International Neuroblastoma Staging System stage 3, 4, P = 0.002), unfavorable International Neuroblastoma Pathology Classification tumor histology (P < 0.001), and high-risk Children's Oncology Group risk group (P = 0.001). In Kaplan-Meier analysis, MYCN RNA levels determined by quantitative in situ hybridization were better than MYCN gene dosages determined by chromogenic in situ hybridization in discriminating good and poor prognostic groups of neuroblastoma patients. In multivariate analysis, we further confirmed that high expression of MYCN RNA was an independent adverse prognostic factor for event-free and overall survival. Furthermore, high expression of MYCN RNA predicted unfavorable survival outcomes for neuroblastoma patients with MYCN non-amplification or high-risk Children's Oncology Group risk group. In conclusion, our study is the first report to show the application of MYCN RNA in situ hybridization in neuroblastoma and established that high expression of MYCN RNA could be a better biomarker than MYCN amplification for predicting poor prognosis of neuroblastoma patients.

The Impact of Hepatitis on Clinical Outcomes for Pediatric Patients with Aplastic Anemia.

OBJECTIVES: To assess the prognostic role of hepatitis in pediatric patients with aplastic anemia and the incidence of hepatitis B among patients with hepatitis-associated aplastic anemia in an area with a previously high prevalence of hepatitis B after nationwide hepatitis B vaccination for 30 years. STUDY DESIGN: Pediatric patients (n = 78) with aplastic anemia were enrolled in this study, including 9 with hepatitis-associated aplastic anemia. We collected the clinical characteristics, etiologies of the aplastic anemia, hepatitis B virus serology and serum hepatitis B viral load, response to the treatments, and survival outcome from the participants. We applied univariate and multivariate Cox regression analysis to evaluate the correlations between clinical features and survival outcome. Survival analysis was done using Cox regression model and Kaplan-Meier curves. RESULTS: Patients with hepatitis-associated aplastic anemia were related to significantly worse survival prognosis when compared with patients with non-hepatitis-associated aplastic anemia, and hepatitis-associated aplastic anemia was the only independent prognostic factor to predict a poor survival outcome in our patients with aplastic anemia by multivariable analysis. In none of the total 78 patients was aplastic anemia related to hepatitis B virus infection. CONCLUSIONS: Patients with hepatitis-associated aplastic anemia had a significantly worse prognosis when compared with patients whose aplastic anemia was not hepatitis-associated. This study demonstrates the potential benefit of hepatitis B vaccination in decreasing the incidence of hepatitis-associated aplastic anemia in children.

The incidence and risk factors of hepatic veno-occlusive disease after hematopoietic stem cell transplantation in Taiwan.

Hepatic veno-occlusive disease (VOD) is a potentially fatal complication of hematopoietic stem cell transplantation (HSCT). We conducted this study to investigate the incidence and risk factors of hepatic VOD for patients receiving HSCT in Taiwan. We retrospectively analyzed the data from a nationwide registry for patients receiving HSCT, which was collected by the Taiwan Society of Blood and Marrow Transplantation. The data collection period was from 2009 to 2014. A total 2345 patients were reviewed and 39 patients among them were diagnosed as having hepatic VOD. The cumulative incidence of hepatic VOD in the whole cohort of 2345 patients was 1.66%. In multivariate analysis, disease diagnosis of myelodysplastic syndrome, chronic HCV infection, condition regimens of bulsulfan intravenously administered, and antithymocyte immunoglobulin were independent factors to predict higher risk of hepatic VOD. The overall mortality rate for patients with hepatic VOD was 79%. Patients with hepatic VOD had significant worse survival outcomes when compared with those without hepatic VOD (P = 0.00063). In conclusion, although the incidence is low, hepatic VOD remains a serious complication after HSCT in Taiwan. The findings of this study could be the basis for developing prophylactic or early treatment strategies for hepatic VOD.

Clinical outcomes of pediatric patients with newly diagnosed rhabdomyosarcoma treated by two consecutive protocols - A single institution report in Taiwan.

BACKGROUND: Taiwan Pediatric Oncology Group (TPOG) initiated two consecutive protocols for treating pediatric patients with rhabdomyosarcoma since 1995. However, the results have not been analyzed and reported yet. The aim of this study is to investigate the treatment results of these two protocols in our hospital and to assess whether the results are comparable to other large-scaled studies. METHODS: Treatment of pediatric patients with rhabdomyosarcoma according to TPOG protocols at National Taiwan University Hospital began in 1995. Between 1995 and 2006, patients were treated by TPOG RMS 95 protocol, which was based on IRS-III/IV. After 2007, patients were treated by TPOG RMS 2007 protocol which was adapted from IRS-V study. The clinical data of patients were obtained retrospectively by reviewing medical records. The date of the latest follow-up was December 31, 2016. RESULTS: Thirty-seven patients were enrolled in this study. The 5-year overall survival (OS) and event-free survival rates of them were 54.7 ± 8.8% and 48.5 ± 8.6%, respectively. The 5-year OS rates for patients treated by TPOG RMS 95 and TPOG RMS 2007 protocols were 55.0 ± 11.1% and 55.9 ± 14.0%, respectively. Age at diagnosis of less than ten years old and receiving operation with gross total or subtotal tumor resection were identified as independent prognostic factors that predicted better outcomes in the multivariate analysis. CONCLUSION: The clinical outcomes of pediatric patients with rhabdomyosarcoma in Taiwan improved dramatically after incorporating two consecutive protocols from TPOG. In addition, the treatment results of these two protocols were comparable to large-scale studies of other countries.

Evolution and contemporary role of metronomic chemotherapy in the treatment of neuroblastoma.

Metronomic chemotherapy refers to the consistent and regular administration of low-dose chemotherapeutic agents over an extended period, with minimal or no extended drug-free intervals. The effectiveness of metronomic chemotherapy is derived from its capacity to impede tumor angiogenesis and foster antitumor immune responses, rather than merely interrupting tumor cell mitosis. Metronomic chemotherapy has been applied in the treatment of neuroblastoma for decades, including patients with newly diagnosed high-risk neuroblastoma and relapsed or refractory neuroblastoma. In the modern era of neuroblastoma treatment, metronomic chemotherapy remains a viable option for maintenance therapy in newly diagnosed neuroblastoma patients without access to autologous stem cell transplantation or immunotherapy, especially in resource-limited regions. For relapsed or refractory patients, metronomic chemotherapy is a suitable alternative for individuals intolerant to intensified treatments or receiving palliative care. Cyclophosphamide, etoposide, vinca alkaloids, and celecoxib constitute the primary components of current metronomic chemotherapy. Given the need for additional research to determine the optimal regimen, comprehensive studies must be conducted to explore and establish standardized metronomic chemotherapy protocols. Additionally, investigating potential biomarkers and clinical prognostic factors is imperative for future advancements in this field.

Terminal deoxynucleotidyl transferase expression in different subtypes of childhood B-cell acute lymphoblastic leukemia.

The lack of expression of terminal deoxynucleotidyl transferase (TdT) is frequently associated with KMT2A-rearranged subtype of pediatric acute lymphoblastic leukemia (ALL). However, this association has not been investigated extensively in the Asian population. A retrospective analysis of TdT expression in pediatric B-cell ALL (B-ALL) was performed in patients treated using the Taiwan Pediatric Oncology Group (TPOG) ALL 2002 and 2013 protocols. Among the 331 patients with B-ALL, 12 patients showed TdT negativity at initial diagnosis. Among these, eight patients showed KMT2A rearrangement (66.7%). Other patients showing negative TdT expression had ETV6::RUNX1, MEF2D-rearranged, and other B-ALL subtypes. However, in the context of KMT2A-rearranged B-ALL (n = 20), only eight patients showed TdT negativity. The 5-year event-free survival and overall survival of patients with and without TdT expression were 83.8% versus 46.8% (P <0.001) and 86.3% versus 55.4% (P = 0.004), respectively. Moreover, several aberrant markers, such as CD2, CD56, CD7, and CD117, were rarely expressed in the B-ALL samples, and if expressed, they were enriched in specific genetic subtypes. The results of this study indicate that immunophenotypic features are correlated with specific genetic subtypes of childhood B-ALL.

Allele-specific polymerase chain reaction can determine the diplotype of NUDT15 variants in patients with childhood acute lymphoblastic Leukemia.

Mercaptopurine intolerance is an adverse effect of mercaptopurine administration in pediatric patients with acute lymphoblastic leukemia (ALL). NUDT15 variants have emerged as major determinants of mercaptopurine intolerance, especially in the Asian population. Two variants, c.55_56insGAGTCG in exon 1 and c.415C > T in exon 3, were commonly detected in the same allele, named NUDT15*1/*2. Although rare, compound heterozygous mutations also occur, with the two variants on different alleles (NUDT15*3/*6), which may confer tolerance to considerably lesser mercaptopurine dosage. Sanger sequencing or pyrosequencing can determine the NUDT15 variants but not the phase. Here, we designed an allele-specific PCR (AS-PCR) with locked nucleic acid-modified primers. A cohort of 63 patients harboring heterozygous c.55_56insGAGTCG and c.415C > T NUDT15 variations was selected for haplotyping using AS-PCR. Of the 63 patients, 60 harbored the NUDT15*1/*2 variant and three harbored compound heterozygous mutations, including two NUDT15*3/*6 and one NUDT15*2/*7 variants. These findings suggest that AS-PCR can determine NUDT15 diplotype and identify patients with compound heterozygous NUDT15 variants, which may enable precise genetic diagnosis of NUDT15. Nevertheless, a larger clinical trial is required to understand the clinical significance of NUDT15*3/*6 in pediatric patients with ALL because of its low incidence rate and challenges in detecting this variant.

C1GALT1 expression predicts a favorable prognosis and suppresses malignant phenotypes via TrkA signaling in neuroblastoma.

Neuroblastoma (NB) is a childhood tumor derived from the sympathoadrenal lineage of the neural crest progenitor cells. Core 1 ß1,3-galactosyltransferase (C1GALT1) controls the crucial step of GalNAc-type O-glycosylation, and its altered expression affects cancer behaviors. However, the role of C1GALT1 in NB tumors remains unclear. Our data showed that C1GALT1 expression was significantly associated with differentiated tumor histology, correlated with TrkA expression, and predicted good prognosis independently in NB. Downregulation of C1GALT1 promotes malignant behaviors of NB cells in vitro and in vivo. Mechanistic investigation showed that knockdown of C1GALT1 in NB cells increased TrkA pulled down through Vicia villosa agglutinin beads, indicating the modulation of O-glycans on TrkA by C1GALT1, and silencing C1GALT1 suppressed the TrkA expression on the NB cell surface. Overexpression of C1GALT1 increased the protein levels of TrkA and promoted the differentiation of NB cells, whereas knockdown of TrkA inhibited C1GALT1-induced neuronal differentiation. Moreover, the inhibitory effects of migration and invasion in C1GALT1-overexpressing NB cells were blocked by TrkA downregulation. C1GALT1 knockdown enhanced AKT phosphorylation but attenuated ERK phosphorylation, and these properties were consistent in C1GALT1-overexpressing NB cells with TrkA knockdown. Taken together, our data provided the first evidence for the existence of GalNAc-type O-glycans on TrkA and altered O-glycan structures by C1GALT1 can regulate TrkA signaling in NB cells. This study sheds light on the novel prognostic role of C1GALT1 in NB and provides new information of C1GALT1 and TrkA on the pathogenesis of NB.

Prognostic Value of Interim 18F-DOPA and 18F-FDG PET/CT Findings in Stage 3-4 Pediatric Neuroblastoma.

PURPOSE: This retrospective study aimed to determine the prognostic value of imaging parameters derived from midtherapy 18F-fluorodihydroxyphenylalanine (18F-DOPA) and 18F-FDG PET in pediatric patients with stage 3-4 neuroblastoma. METHODS: We enrolled 32 stage 3-4 pediatric neuroblastoma patients who underwent 18F-DOPA and 18F-FDG PET/CT scans before and after 3 chemotherapy cycles. We measured metabolic and volumetric parameters and applied a metabolic burden scoring system to evaluate the primary tumor extent and soft tissue metastases and that of bone/bone marrow involvement. The associations between these parameters and clinical outcomes were investigated. RESULTS: Over a median follow-up period of 47 months (range, 3-137 months), 16 patients experienced disease progression, and 13 died. After adjustment for clinical factors, multivariate Cox proportional hazard models showed that interim tumor FDG/FDOPA SUVmax (hazard ratio [HR], 5.94; 95% confidence interval [CI], 1.10-34.98) and interim FDOPA whole-body metabolic burden scores (WBMB) (HR, 7.30; 95% CI, 1.50-35.50) were significant prognostic factors for overall survival (OS). Only interim FDOPA WBMB scores (HR, 7.05; 95% CI, 1.02-48.7) were predictive of progression-free survival. Based on median cutoff values, prognosis (OS and progression-free survival) was significantly associated with an interim FDOPA WBMB score ≥21.92 (all P < 0.05) and interim tumor FDG/FDOPA (SUVmax) score ≥0.57 with poor OS (P < 0.05). CONCLUSIONS: Our results indicate that midtreatment FDG and FDOPA PET/CT could serve as prognostic markers in stage 3-4 neuroblastoma patients.

Sequential Approach to Improve the Molecular Classification of Childhood Acute Lymphoblastic Leukemia.

Identification of specific leukemia subtypes is a key to successful risk-directed therapy in childhood acute lymphoblastic leukemia (ALL). Although RNA sequencing (RNA-seq) is the best approach to identify virtually all specific leukemia subtypes, the routine use of this method is too costly for patients in resource-limited countries. This study enrolled 295 patients with pediatric ALL from 2010 to 2020. Routine screening could identify major cytogenetic alterations in approximately 69% of B-cell ALL (B-ALL) cases by RT-PCR, DNA index, and multiplex ligation-dependent probe amplification. STIL-TAL1 was present in 33% of T-cell ALL (T-ALL) cases. The remaining samples were submitted for RNA-seq. More than 96% of B-ALL cases and 74% of T-ALL cases could be identified based on the current molecular classification using this sequential approach. Patients with Philadelphia chromosome-like ALL constituted only 2.4% of the entire cohort, a rate even lower than those with ZNF384-rearranged (4.8%), DUX4-rearranged (6%), and Philadelphia chromosome-positive (4.4%) ALL. Patients with ETV6-RUNX1, high hyperdiploidy, PAX5 alteration, and DUX4 rearrangement had favorable prognosis, whereas those with hypodiploid and KMT2A and MEF2D rearrangement ALL had unfavorable outcomes. With the use of multiplex ligation-dependent probe amplification, DNA index, and RT-PCR in B-ALL and RT-PCR in T-ALL followed by RNA-seq, childhood ALL can be better classified to improve clinical assessments.

Treatment outcomes of pediatric acute myeloid leukemia: a retrospective analysis from 1996 to 2019 in Taiwan.

Improvement in outcomes of children with acute myeloid leukemia (AML) is attributed to several refinements in clinical management. We evaluated treatment outcomes of Taiwanese pediatric AML patients in the past 20 years. Overall, 860 de novo AML patients aged 0-18 years and registered in the Childhood Cancer Foundation of R.O.C during January 1996-December 2019 were included. Survival analysis was performed to identify factors that improved treatment outcomes. Regardless of treatment modalities used, patients during 2008-2019 had better 5-year event-free survival (EFS) and overall survival (OS) rates than patients during 1996-2007. For patients received the TPOG-AML-97A treatment, only 5-year OS rates were significantly different between patients diagnosed before and after 2008. Patients with RUNX1-RUNX1T1 had similar relapse-free survival rates, but 5-year OS rates were better during 2008-2019. However, the survival of patients who received hematopoietic stem-cell transplantations (HSCT) did not differ significantly before and after 2008. For patients without relapse, the 5-year OS improved during 2008-2019. Non-relapse mortality decreased annually, and cumulative relapse rates were similar. In conclusion, 5-year EFS and OS rates improved during 2008-2019, though intensities of chemotherapy treatments were similar before and after 2008. Non-relapse mortality decreased gradually. Further treatment strategies including more intensive chemotherapy, novel agents' use, identification of high-risk patients using genotyping and minimal residual disease, early intervention of HSCT, and antibiotic prophylaxis can be considered for future clinical protocol designs in Taiwan.

The prognostic roles of and correlation between ALK and MYCN protein expression in neuroblastoma.

AIMS: To investigate the relations between anaplastic lymphoma kinase (ALK) and v-myc myelocytomatosis viral related oncogene neuroblastoma derived homolog (MYCN) protein expression and their prognostic roles in neuroblastoma tumours. METHODS: Sixty-one neuroblastoma tumours obtained at diagnosis were stained with anti-MYCN and anti-ALK antibodies by immunohistochemical staining. The correlations between protein expression of MYCN, ALK and clinicopathological and biological variables of neuroblastoma tumours were analysed. RESULTS: High expression of ALK protein could be detected in 25 (41%) and high expression of MYCN protein could be detected in 24 (39.3%) of the 61 neuroblastoma tumours, respectively. The majority of neuroblastoma tumours with evident of ALK or MYCN protein high expression exhibited undifferentiated or poorly differentiated histology (30/35, 85.7%). ALK or MYCN protein high expression in neuroblastoma tumours was associated with adverse clinical prognostic factors and ALK protein high expression was significantly associated with MYCN protein high expression. In addition, either ALK or MYCN protein high expression in neuroblastoma tumours was the independent adverse prognostic factor and also predicted worse survival outcomes for neuroblastoma patients with MYCN non-amplified status or non-high-risk Children's Oncology Group grouping. CONCLUSIONS: Our study showed a novel coordinately prognostic role of ALK and MYCN protein expression in neuroblastoma and is the first report to demonstrate the correlation between ALK and MYCN protein expression in primary neuroblastoma tumours.