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Simple Summary: Liquid biopsy is a technique that uses minimally invasive or noninvasive methods to detect disease biomarkers in biofluids, such as blood and urine. For childhood cancers, this approach is promising, especially when tissue biopsies are challenging. By analyzing tiny particles called extracellular vesicles, the small particles in biofluids which carry genetic and molecular information from cancer cells, this liquid biopsy technique can aid early diagnosis, treatment monitoring, and outcome prediction, potentially improving the outcomes of childhood cancers. This review article introduces the concept of extracellular vesicle liquid biopsy, summarizes the progress that is being made in the diagnosis of multiple types of pediatric malignancies, and provides prospects for using this extracellular vesicle method to guide the development of novel cancer therapeutics. Liquid biopsy involves the utilization of minimally invasive or noninvasive techniques to detect biomarkers in biofluids for disease diagnosis, monitoring, or guiding treatments. This approach is promising for the early diagnosis of childhood cancer, especially for brain tumors, where tissue biopsies are more challenging and cause late detection. Extracellular vesicles offer several characteristics that make them ideal resources for childhood cancer liquid biopsy. Extracellular vesicles are nanosized particles, primarily secreted by all cell types into body fluids such as blood and urine, and contain molecular cargos, i.e., lipids, proteins, and nucleic acids of original cells. Notably, the lipid bilayer-enclosed structure of extracellular vesicles protects their cargos from enzymatic degradation in the extracellular milieu. Proteins and nucleic acids of extracellular vesicles represent genetic alterations and molecular profiles of childhood cancer, thus serving as promising resources for precision medicine in cancer diagnosis, treatment monitoring, and prognosis prediction. This review evaluates the recent progress of extracellular vesicles as a liquid biopsy platform for various types of childhood cancer, discusses the mechanistic roles of molecular cargos in carcinogenesis and metastasis, and provides perspectives on extracellular vesicle-guided therapeutic intervention. Extracellular vesicle-based liquid biopsy for childhood cancer may ultimately contribute to improving patient outcomes. [ABSTRACT FROM AUTHOR]

Purpose: A multimodality approach is generally considered for pediatric low-grade gliomas (LGG); however, the optimal management remains uncertain. The objective of the study was to evaluate treatment outcomes of pediatric LGG, focusing on long-term survival and factors related to outcomes. Methods: A retrospective review of 77 pediatric LGG cases treated at Ramathibodi Hospital, Thailand between 2000 and 2018 was performed. The inclusion criteria were all pediatric LGG cases aged ≤ 15 years. Diffuse intrinsic pontine gliomas and spinal cord tumors were excluded. Results: The median follow-up time was 8.2 years (range, 0.6–19.7). The median age at diagnosis was 6.2 years (interquartile range, 3.6–11.4). Treatments modality included tumor surgery (93%), chemotherapy (40%), and radiation therapy (14%). The 10-year overall survival (OS) and 10-year progression-free survival were 94% and 59%, respectively, for the entire cohort. The 10-year OS was 100% in three subgroups of patients: pilocytic subtype, WHO grade 1 tumors, and recipient of gross total resection. After multivariable analysis, no tumor surgery had a significantly unfavorable influence on overall survival. Conclusions: With a multimodality approach, pediatric LGGs had excellent outcome. Gross total resection is the standard primary treatment. Chemotherapy is the alternative standard treatment in incomplete resection cases, unresectable patients, or patients with progressive disease. Radiation therapy should be reserved as a salvage treatment option because of late complications that usually affect patients' quality of life. [ABSTRACT FROM AUTHOR]

Objectives: Patients with high‐risk hematologic diseases require intensive modalities, including high‐dose chemotherapy and allogeneic hematopoietic stem cell transplantation (allo‐HSCT). Haploidentical T‐cell–replete transplantation is a logical choice because of the limited availability of matched sibling donors and the prolonged time needed to identify matched unrelated donors in Thailand. Methods: The clinical outcomes data of 43 patients undergoing allo‐HSCT were reviewed. All patients had high‐risk hematologic malignancies, were younger than 20 years, and were in complete cytological remission at the time of allo‐HSCT. We used two different conditioning regimens: total body irradiation (TBI) combined with cyclophosphamide, fludarabine, and melphalan (n = 23) and thiotepa combined with fludarabine and busulfan (n = 20). All patients received a graft‐versus‐host disease prophylaxis regimen consisting of cyclophosphamide, mycophenolate mofetil, and a calcineurin inhibitor or sirolimus. Results: There was no difference in engraftment between patients receiving either of the regimens. After a median follow‐up of 35.8 (range, 0.6–106.2) months, the overall survival (OS) and event‐free survival (EFS) rates were 62.4% and 54.7%, respectively. OS and EFS were comparable between the respective regimens. Conclusions: We conclude that thiotepa‐based conditioning has similar efficacy and tolerability as TBI‐based conditioning for haploidentical HSCT with post‐transplant cyclophosphamide. [ABSTRACT FROM AUTHOR]

Background: In 2013, the Thai Pediatric Oncology Group (ThaiPOG) introduced a national protocol in which highdose chemotherapy plus stem cell rescue is performed without immunotherapy. Methods: This study aimed to elucidate the outcomes of high-risk neuroblastoma (HR-NB) patients treated with the ThaiPOG protocol. This retrospective cohort review included 48 patients (30 males, 18 females) with a median age of 3 years (range, 8 months to 18 years) who were treated at 5 ThaiPOG treatment centers in Thailand in 2000-2018. Results: Eight of the 48 patients showed MYCN amplification. Twenty-three patients (48%) received 131I-meta-iodobenzylguanidine prior to high-dose chemotherapy and stem cell rescue. The majority of patients achieved a complete or very good response prior to consolidation treatment. The 5-year overall survival (OS) and event-free survival (EFS) rates were 45.1% and 40.4%, respectively. Patients aged >2 years had a nonsignificantly higher mortality risk (hazard ratio [HR], 2.66; 95% confidence interval [CI], 0.92-7.68; P=0.07). The MYCN amplification group had lower OS and EFS rates than the MYCN nonamplification group, but the difference was not statistically significant (45% OS and 37.5% EFS vs. 33.3% OS and 16.6% EFS; P=0.67 and P=0.67, respectively). Cisretinoic acid treatment for 12 months was a strong prognostic factor that could reduce mortality rates among HR-NB patients (HR, 0.27; 95% CI, 0.09-0.785; P=0.01). Conclusion: High-dose chemotherapy plus stem cell rescue followed by cis-retinoic acid for 12 months was well tolerated and could improve the survival rates of patients with HR-NB. [ABSTRACT FROM AUTHOR]

Aims: The purpose of this study was to design and manufacture CD19 chimeric antigen receptor (CAR)‐modified T cells for clinical use in Thailand, as a model for how this technology can be directly applied at individual institutions treating high‐risk leukemia patients. Methods: We constructed second‐generation CAR T cells expressing CD19 scFV‐CD28‐CD3ζ with different lengths of the spacer region: full, intermediate, and short length, by using a lentiviral vector. We wanted to determine whether the difference in length of the spacer would affect the cytotoxic potential of the CD19 CAR T cells against the leukemic cells. Results: We found that all constructs of CD19 CAR T cells exhibited a similar level of cytotoxicity against several human lymphoma and leukemia cell lines. For the clinical application, we chose the intermediate length spacer construct CD19 CAR T cells, hypothesizing that the highest transduction efficiency coupled with a slower initial proliferation in vitro might lead to effective leukemic cell kill, yet a lower probability for serious clinical side effects. We then tested the clinical efficacy of our CD19 CAR T cells in one patient with refractory/relapsed acute B‐cell lymphoblastic leukemia. This patient indeed had minimal clinical side effects after the CAR T‐cell infusion, and he remains in an unmaintained, ongoing complete remission 10+ months after his T‐cell treatment. Conclusion: Our CD19 CAR T cells demonstrated efficacies in acute lymphoblastic B‐cell leukemia, and will be used to establish an immunotherapeutic program for high‐risk B‐cell acute lymphoblastic leukemia in Thailand. We propose that this approach can be used as a model for how this new exciting technology can be applied directly at individual institutions that treat (a large number of) patients with high‐risk leukemia. [ABSTRACT FROM AUTHOR]

Purpose. To investigate the clinical presentations and outcomes of retinoblastoma in relation to the advent of new multimodal treatments in Thailand. Patients and Methods. Retrospective case series. We evaluated the clinical presentation, staging, details of treatment, and treatment outcomes of retinoblastoma patients who were treated at Ramathibodi Hospital, Bangkok, Thailand, between January 1, 2007, and December 31, 2018. The log-rank test was used to explore clinical characteristics and treatment modalities that affected globe salvage and survival curves. Results. This study included 124 eyes of 81 patients with retinoblastoma. Forty-three patients (53.1%) had bilateral retinoblastoma. The median age at diagnosis was 8 months (range, 1–48 months). Of 124 eyes, 9 eyes (7.3%) had extraocular retinoblastoma and 115 eyes (92.7%) had intraocular retinoblastoma, which were classified by the International Classification of Retinoblastoma (ICRB) as group A, 4 eyes (3.5%); group B, 19 eyes (16.5%); group C, 6 eyes (5.2%); group D, 31 eyes (27%); and group E, 56 eyes (47.8%). Treatment included systemic chemotherapy, intra-arterial chemotherapy, ruthenium-106 plaque brachytherapy, external beam radiation therapy, cryotherapy, transpupillary thermotherapy, subtenon chemotherapy, and intravitreal chemotherapy. At the median follow-up period of 38.4 months (range, 0.2–148.2 months), the overall globe salvage rate of intraocular retinoblastoma was 51.7%. For unilateral retinoblastoma, globe salvage rate was 37.5% (group B, 100%; group C, 100%; group D, 50%; and group E, 18.8%). For bilateral intraocular retinoblastoma, the globe salvage rate was 57.8% (group A, 100 %; group B, 94.4%; group C, 100%; group D, 64.7%; and group E, 28.2%). The overall survival rate was 93.8%. Conclusions. Recent advanced treatment modalities have improved the probability of globe salvage. However, enucleation remains an important life-saving intervention in many advanced cases. [ABSTRACT FROM AUTHOR]

Background: In the modern era of chemotherapy, the outcome of pediatric non‐Hodgkin lymphoma (NHL) continues to improve internationally. Limited data such as information on epidemiology and survival, however, are available in Asian countries. Methods: Children (≤15 years old) diagnosed with histologically proven NHL from 1998 to 2014 were retrospectively analyzed. Results: In total, 114 patients were enrolled; they were predominantly male (65.8%) and had advanced disease (stage III, IV; 71.9%). Of these, 22.8% had Burkitt lymphoma, 20.2% had diffuse large B‐cell lymphoma, 21.1% had lymphoblastic lymphoma, 20.2% had large cell lymphoma, and 15.8% had peripheral T‐cell lymphoma. Twenty‐nine patients died, especially of uncontrolled disease (62.1%) and infection (20.7%). During a median follow up of 78.4 months, Kaplan–Meier 5 year event‐free and overall survival rates were 71.5% ± 4.3% and 74.8% ± 4.1%, respectively, regardless of subtype. B symptoms (i.e. systemic symptoms of fever, night sweats, and weight loss that can be associated with both Hodgkin's lymphoma and non‐Hodgkin's lymphoma) and advanced disease had a significant negative impact on 5 year survival. No other prognostic factor was found, but survival tended to have a negative correlation with age. Conclusions: Pediatric NHL is aggressive, with a high prevalence of peripheral T‐cell lymphoma. The present treatment stratification seems to be effective compared with that used in developed countries. [ABSTRACT FROM AUTHOR]

Background: Hematopoietic stem cell transplantation (HSCT) is the only curative treatment available to severe thalassemic patients. The treatment, however, is very costly, particularly in the context of low and middle income countries, and no studies have been carried out to explore its economic justifiability. This study aimed to estimate the cost-utility of HSCT compared with blood transfusions combined with iron chelating therapy (BT-ICT) for severe thalassemia in Thailand, and to investigate the affordability of HSCT using a budget impact analysis. Methods: A Markov model was used to estimate the relevant costs and health outcomes over the patients' lifetimes taking a societal perspective as recommended by Thailand's health technology assessment guidelines. All future costs and outcomes were discounted at a rate of 3% per annum. Primary outcomes of interest were lifetime costs, quality adjusted life years (QALYs) gained, and the incremental cost-effectiveness ratio (ICER) in Thai baht (THB) per QALY gained. Results: Compared to BT-ICT, the incremental cost-effectiveness ratio increased with patient age from 80,700 to 183,000 THB per QALY gained for related HSCT and 209,000 to 953,000 THB per QALY gained for unrelated HSCT among patients aged 1 to 15 years (US$1= 34 THB). The governmental budget impact analysis showed that providing 200 related HSCT to patients aged 1 to 10 years, in accordance with the current infrastructure limitations, would initially require approximately 90 million additional THB per year. Conclusions: At a societal willingness to pay of 100,000 THB per QALY gained, related HSCT was likely to be a cost-effective and affordable treatment for young children with severe thalassemia in Thailand. [ABSTRACT FROM AUTHOR]

Aim: Polymorphisms of the UGT1A1 gene, SLCO1B1 gene and GST gene have been associated with significant hyperbilirubinemia. We would like to determine whether the variation of UGT1A1 gene, SLCO1B1 gene and GST gene may play a significant role in neonatal hyperbilirubinemia in Thai infants. Methods: Ninety-one study subjects (hyperbilirubinemic group) and 86 control subjects were studied. Results: The cause of neonatal hyperbilirubinemia could not be identified in 64 infants (70.3%), ABO blood group incompatibility in 14.3% and Glucose-6-phosphate dehydrogenase (G-6-PD) deficiency in 8.8%. In the hyperbilirubinemic group, 23 of 91 (25.3%) infants demonstrated variant of UGT1A1 at nucleotides (nt) 211 as compared to 6 of 86 (7%) in the control group (p = 0.001). There were no significant differences between groups in the variants UGT1A1 at nt 686, SLCO1B1 gene at nt 388, 463 and the GST gene. Male infants with G-6-PD deficiency were associated with hyperbilirubinemia (21.2% vs. 4.8% in the control group) with an odds ratio (OR) of 5.37 (p =0.02). The relationship between G-6-PD and variant in UGT1A1 gene at nt 211 could not be determined. Conclusion: Thai infants with variant in the UGT1A1 at nt 211 or with G-6-PD deficiency are at higher risk for developing neonatal hyperbilirubinemia. [ABSTRACT FROM AUTHOR]

This is a retrospective study of 24 pediatric venous thromboembolism (VTE) patients with or without pulmonary embolism, conducted in Bangkok, Thailand, between 1981 and 2005. The incidence rate of VTE in Thai children was 3.9/10,000 hospital admissions per year. The median age was 11.7 years. Seventy-five percent of the patients had at least one associated medical condition accounting for the VTE; the two most common conditions, however, were infection and malignancy. Pulmonary embolism occurred in 29% of patients. Observed outcomes of VTE in this series included death (13%), postphlebitic syndrome (13%), and recurrence (26%). Genetic risk factors were explored in 19 patients, and no factor V Leiden or prothrombin 20210 mutations were detected. Protein C deficiency was found in 4 patients. [ABSTRACT FROM AUTHOR]

Background: Volatile anesthetic agents used during surgery have immunomodulatory effects which could affect postoperative outcomes. Recognizing that regulatory T cells (Tregs) plays crucial roles in transplant tolerance and high peripheral blood Tregs associated with stable kidney graft function, knowing which volatile anesthetic agents can induce peripheral blood Tregs increment would have clinical implications. This study aimed to compare effects of desflurane and sevoflurane anesthesia on peripheral blood Tregs induction in patients undergoing living donor kidney transplantation. Methods: A prospective, randomized, double-blind trial in living donor kidney transplant recipients was conducted at a single center, tertiary-care, academic university hospital in Thailand during August 2015 – June 2017. Sixty-six patients were assessed for eligibility and 40 patients who fulfilled the study requirement were equally randomized and allocated to desflurane versus sevoflurane anesthesia during transplant surgery. The primary outcome included absolute changes of peripheral blood CD4+CD25+FoxP3+Tregs which measured by flow cytometry and expressed as the percentage of the total population of CD4+ T lymphocytes at pre-exposure (0-h) and post-exposure (2-h and 24-h) to anesthetic gas. P-value < 0.05 denoted statistical significance. Results: Demographic data were comparable between groups. No statistical difference of peripheral blood Tregs between desflurane and sevoflurane groups observed at the baseline pre-exposure (3.6 ± 0.4% vs. 3.1 ± 0.4%; p = 0.371) and 2-h post-exposure (3.0 ± 0.3% vs. 3.5 ± 0.4%; p = 0.319). At 24-h post-exposure, peripheral blood Tregs was significantly higher in desflurane group (5.8 ± 0.5% vs. 4.1 ± 0.3%; p = 0.008). Within group analysis showed patients receiving desflurane, but not sevoflurane, had 2.7% increase in peripheral blood Treg over 24-h period (p < 0.001). Conclusion: This study provides the clinical trial-based evidence that desflurane induced peripheral blood Tregs increment after 24-h exposure, which could be beneficial in the context of kidney transplantation. Mechanisms of action and clinical advantages of desflurane anesthesia based on Treg immunomodulation should be investigated in the future. Trial registration: ClinicalTrials.gov, NCT02559297. Registered 22 September 2015 - retrospectively registered [ABSTRACT FROM AUTHOR]

Background: Neuroblastoma is the most common extra-cranial solid tumor among children. Despite intensive treatment, patients with advanced disease mostly experience dismal outcomes. Here, we proposed the use of topotecan and cyclophosphamide containing induction regimen as an upfront therapy to high risk neuroblastoma patients.Methods: Patients with high risk neuroblastoma undergoing ThaiPOG high risk neuroblastoma protocol from 2016 to 2017 were studied. All patients received 6 cycles of induction regimen consisting of 2 cycles topotecan (1.2 mg/m2/day) and cyclophosphamide (400 mg/m2/day) for 5 days followed by cisplatin (50 mg/m2/day) for 4 days combined with etoposide (200 mg/m2/day) for 3 days on the third and fifth cycles and cyclophosphamide (2100 mg/m2/day) for 2 days combined with doxorubicin (25 mg/m2/day) and vincristine (0.67 mg/m2/day) for 3 days on the fourth and sixth cycles. Treatment response after the 5th cycle before surgery and treatment-related toxicities after each topotecan containing induction cycle were evaluated. Relevant prognostic factors were analyzed to measure the treatment response among those patients.Results: In all, 107 high risk neuroblastoma patients were enrolled in the study. After the 5th cycle of induction regimen, the patients achieved complete response (N = 2), very good partial response (N = 40), partial response (N = 46) and mixed response (N = 19). None of the patients experienced stable disease or disease progression. The most significant prognostic factor was type of healthcare system. The most common adverse effect was febrile neutropenia followed by mucositis, diarrhea and elevated renal function.Conclusion: The topotecan and cyclophosphamide containing induction regimen effectively provides favorable treatment response. The regimen is well tolerated with minimal toxicity among patients with high risk neuroblastoma in Thailand. [ABSTRACT FROM AUTHOR]

Abstract: Background: Folate is an important micronutrient molecule participating in DNA synthesis, methylation and repair mechanisms. Genetic polymorphisms in folate pathway related enzymes including methylenetetrahydrofolate reductase (MTHFR) C677T and A1298C, methionine synthase (MTR) A2756G, thymidylate synthase (TS) 28-bp tandem repeat, and reduced folate carrier (RFC) G80A have been shown to be associated with increased susceptibility for several cancers. The aim of the present study was to evaluate whether single nucleotide polymorphisms in the genes encoding enzymes of the folate pathway predispose to any CNS tumors in Thai children. Methods: In the present case–control study, we investigated these polymorphisms in genomic DNA from peripheral blood mononuclear cells in 73 Thai children with various types of central nervous system tumors and in 205 age and sex matched controls. Results: Thirty-one out of 73 patients were diagnosed with glial tumors (astrocytoma, oigodendroglioma and ependymoma), 28 with embryonal CNS tumors (medulloblastoma, pinealoblastoma and primitive neuroectodermal tumor), 13 with germ cell tumors and 1 with meningioma. We found that the homozygous CC allele of MTHFR A1298C conferred an increased risk of embryonal CNS tumors (OR: 3.9; 95% CI: 1.3–11.4, p =0.02). Conclusion: Our findings thus suggest that folate metabolism may play a role in the pathogenesis of certain specific subtypes of pediatric brain tumor in Thai children, especially embryonal CNS tumors. [Copyright &y& Elsevier]