Incidence and survival rates of hematological malignancies in Japanese children and adolescents (2006–2010): based on registry data from the Japanese Society of Pediatric Hematology

Ambient air pollution as a time-varying covariate in the survival probability of childhood cancer patients in the upper Northern Thailand

The objective of this study is to determine the possible association between exposure to air pollution and the risk of death from cancer during childhood in upper northern Thailand. Data were collected on children aged 0-15 years old diagnosed with cancer between January 2003 and December 2018 from the Chiang Mai Cancer Registry. Survival rates were determined by using Kaplan-Meier curves. Cox proportional hazard models were used to investigate associations of potential risk factors with the time-varying air pollution level on the risk of death. Of the 540 children with hematologic cancer, 199 died from any cause (overall mortality rate = 5.3 per 100 Person-Years of Follow-Up (PYFU); 95%CI = 4.6-6.0). Those aged less than one year old (adjusted hazard ratio [aHR] = 2.07; 95%CI = 1.25-3.45) or ten years old or more (aHR = 1.41; 95%CI = 1.04-1.91) at the time of diagnosis had a higher risk of death than those aged one to ten years old. Those diagnosed between 2003 and 2013 had an increased risk of death (aHR = 1.65; 95%CI = 1.13-2.42). Of the 499 children with solid tumors, 214 died from any cause (5.9 per 100 PYFU; 95%CI = 5.1-6.7). Only the cancer stage remained in the final model, with the metastatic cancer stage (HR = 2.26; 95%CI = 1.60-3.21) and the regional cancer stage (HR = 1.53; 95%CI = 1.07-2.19) both associated with an increased risk of death. No association was found between air pollution exposure and all-cause mortality for either type of cancer. A larger-scale analytical study might uncover such relationships.

Rituximab with standard LMB chemotherapy in pediatric high-risk mature B-cell non-Hodgkin lymphoma: A report from the JPLSG B-NHL14 trial

BACKGROUND

The benefit of adding rituximab to standard lymphomes malins B (LMB) chemotherapy for children with high-risk mature B-cell non-Hodgkin lymphoma (B-NHL) has previously been demonstrated in an international randomized phase III trial, to which the Japanese Pediatric Leukemia/Lymphoma Study Group could not participate.

METHODS

To evaluate the efficacy and safety of rituximab in combination with LMB chemotherapy in Japanese patients, we conducted a single-arm multicenter trial.

RESULTS

In this study, 45 patients were enrolled between April 2016 and September 2018. A total of 33 (73.3%), 5 (11.1%), and 6 (13.3%) patients had Burkitt lymphoma/leukemia, diffuse large B-cell lymphoma, and aggressive mature B-NHL, not otherwise specified, respectively. Ten (22.2%) and 21 (46.7%) patients had central nervous system disease and leukemic disease, respectively. The median follow-up period was 47.5 months. Three-year event-free survival and overall survival were 97.7% (95% confidence interval, 84.9-99.7) and 100%, respectively. The only event was relapse, which occurred in a patient with diffuse large B-cell lymphoma. Seven patients (15.6%) developed Grade 4 or higher non-hematologic adverse events. Febrile neutropenia was the most frequent Grade 3 or higher adverse event after the pre-phase treatment, with a frequency of 54.5%.

CONCLUSION

The efficacy and safety of rituximab in combination with LMB chemotherapy in children with high-risk mature B-NHL was observed in Japan.

Epidemiology of pediatric hematological malignancies in Kazakhstan: Data from Unified National Electronic Healthcare System 2014-2021

We aimed to describe incidence and all-cause mortality of hematological pediatric malignancies (leukemia and lymphomas) in Kazakhstan based on nationwide large-scale healthcare data from the Unified National Electronic Healthcare System (UNEHS) for the 2014-2021 year period. The cohort included data of patients less than 18 years old with the diagnosis of hematological malignancies registered in the UNEHS (inpatient and outpatient registries) for the year period 2014-2021. Descriptive statistics were conducted to indicate socio-demographic characteristics of the cohort. Incidence and all-cause mortality were calculated per 100,000 population. Cox proportional hazard regression analysis was performed to investigate the association between determinants with the all-cause mortality. The total cohort consisted of 3357 children with leukemia and 1474 children with lymphomas. The mean age at diagnosis of leukemia and lymphomas was 7.3 ± 4.7 and 9.9 ± 4.9 years, respectively. The incidence rate of hematological malignancies was 6.8 per 100,000 in 2021. Patients with ALL had a higher incidence rate than patients with AML (3.4 and 1.2 per 100,000 in 2021, respectively). The incidence rate of HL and NHL was relatively similar which varied from 0.6 to 2.6 per 100,000 in 2014-2021. All-cause mortality of pediatric hematological malignancies varied from 1.1 to 1.5 per 100,000 in 2014-2021, with the peak in 2016 (1.7 per 100,000). Younger age is significantly associated with increased risk of all-cause mortality in children with AML.

CONCUSION

Patients with ALL had a higher incidence rate than patients with AML. The incidence rate of HL and NHL was relatively similar. All-cause mortality rates for leukemia and lymphomas were quite stable during the study period. Younger age is significantly associated with increased all-cause mortality among AML patients. However, there is no significant association of age with all-cause mortality among ALL, HL and NHL. In order to obtain more reliable data and analysis on pediatric (hematological) malignancies, specific registries for childhood tumors (including detailed information on relapses, treatments, short and long-term side effects, and specific death causes) should be implemented.

WHAT IS KNOWN

• Leukemias and lymphomas together account for around 45% of all pediatric malignancies. • Lymphoma accounts for 12% of all childhood malignancies; non-Hodgkin's lymphomas (NHL) are more frequent than Hodgkin's lymphomas (HL).

WHAT IS NEW

• The incidence rate of ALL was higher than the incidence rate of AML throughout the whole study period, whereas all-cause mortality of ALL and AML was quite stable. • According to Cox PH analysis, younger age (0-5 years old) was associated with a higher risk of death among AML children compared to older children, and no significant association of age was observed with all-cause mortality among ALL and lymphomas.

Case report: Exploring the utility of whole-body bone scintigraphy for pediatric Langerhans cell histiocytosis: insights from clinical practice

Purpose

This mini-review delves into the realm of Langerhans cell histiocytosis (LCH) in children, focusing on its skeletal involvement. By synthesizing pertinent literature, we sought to provide a comprehensive understanding of LCH's clinical and radiographic spectrum. Our study then demonstrates the diagnostic prowess of whole-body 99mTc-methyl diphosphonate (MDP) scintigraphy in LCH cases, underscoring its value in tandem with existing knowledge.

Methods

Our approach involved an extensive literature review that contextualized LCH within the current medical landscape. Subsequently, we presented a case series featuring five pediatric instances of skeletal LCH, one accompanied by soft tissue infiltration. The principal aim was to illuminate the diagnostic and staging potential of whole-body 99mTc-MDP scintigraphy, augmenting existing insights.

Results

Through meticulous literature synthesis, we highlighted pediatric LCH's protean clinical manifestations and radiological variability. Aligning with this spectrum, our case series underscored the role of 99mTc-MDP scintigraphy in diagnosing and staging LCH. Among the five pediatric cases, one demonstrated concurrent soft tissue involvement. This aligns with the multifaceted nature of LCH presentations.

Conclusion

Pediatric LCH can present with a wide range of clinical and radiologic features. By amalgamating our cases with extant literature, we stress the necessity of a multimodal strategy. 99mTc-MDP scintigraphy emerged as an indispensable tool for accurate staging and soft tissue detection. Our findings collectively advocate for a holistic approach to managing LCH, ensuring informed therapeutic decisions for optimal patient outcomes.

Pediatric leukemia and maternal occupational exposure to anticancer drugs: the Japan Environment and Children's Study

ABSTRACT

Occupational exposure to medical agents and ionizing radiation has been suggested as a possible risk factor for childhood cancer. However, the relationship between such exposure and pediatric malignant neoplasms has not yet been comprehensively studied. This cohort study aimed to investigate the association between parental occupational exposure to hazardous medical agents or ionizing radiation and the risk of childhood cancer in offspring. Data from a large birth cohort in Japan, which included 104 062 fetuses, were analyzed. The primary outcome was the development of leukemia or brain tumors diagnosed by community physicians during the first 3 years after birth. Exposure factors were medical agents, including anticancer agents, ionizing radiation, and anesthetics, handled by mothers during pregnancy or by fathers for 3 months before conception. The incidence of leukemia, but not of brain tumors, was higher in mothers exposed to anticancer drugs. Multivariable regression analysis showed that maternal exposure to anticancer drugs was associated with an increased risk of leukemia in offspring older than 1 year (adjusted relative risk, 7.99 [95% confidence interval, 1.98-32.3]). Detailed information obtained from medical certificates of patients with identified leukemia revealed no infant leukemia but acute lymphoblastic leukemias in the exposed group. Our findings suggest that maternal occupational exposure to anticancer drugs may be a potential risk factor for acute lymphoblastic leukemia in offspring older than 1 year. Effective prevention methods may be necessary to prevent maternal exposure to anticancer drugs and to reduce the risk of childhood malignant neoplasms.

Recent progress in pediatric lymphoblastic leukemia

The probability of long-term survival for children with lymphoblastic leukemia has improved dramatically over recent decades, mainly owing to advances in genomic analysis techniques, which have improved our understanding of the nature of leukemic cells and prognostic prediction based on the evaluation of precise treatment response. Risk-adjusted chemotherapy based on these advances has simultaneously reduced relapse rates and minimized complications. In addition, recent genomic analyses have deepened our understanding of the pathogenesis of leukemia and revealed the involvement of germline variations in the clinical course of leukemia treatment. Additionally, advances in minimal residual disease assays and the introduction of immunotherapy are expected to further improve therapeutic analyses. Further advances in clinical and translational research are anticipated to improve survival to 100% in a healthy state.

Evolution and optimization of therapies for acute lymphoblastic leukemia in infants

Acute lymphoblastic leukemia (ALL) in infants accounts for less than 5% of pediatric ALL and is biologically and clinically unique. Approximately 70% to 80% of cases present as an aggressive leukemia with KMT2A gene rearrangement (KMT2A-r), which is one of the most difficult-to-cure forms of pediatric leukemia. Owing to continuing global efforts through multicenter clinical trials since the mid-1990s, a standard of care for infant KMT2A-r ALL, including minimal residual disease-based risk stratifications, "hybrid chemotherapy" incorporating myeloid leukemia-like drugs (e.g., cytarabine) into the ALL chemotherapy backbone, and selective use of allogeneic hematopoietic stem cell transplantation, has now been established. However, there are still many concerns regarding treatment of infants with KMT2A-r ALL, including insufficient efficacy of the current standard therapies, limited pharmacokinetic/pharmacodynamic data on drugs in infants, and management of both acute and late toxicities. Refinements in risk stratification based on leukemia biology, as well as the introduction of emerging novel immunotherapies and molecular-targeted drugs to contemporary therapy, through international collaboration would provide key solutions for further improvement in outcomes.

Molecular characterization of an embryonal rhabdomyosarcoma occurring in a patient with Kabuki syndrome: report and literature review in the light of tumor predisposition syndromes

Kabuki syndrome is a well-recognized syndrome characterized by facial dysmorphism and developmental delay/intellectual disability and in the majority of patients a germline variant in KMT2D is found. As somatic KMT2D variants can be found in 5-10% of tumors a tumor predisposition in Kabuki syndrome is discussed. So far less than 20 patients with Kabuki syndrome and a concomitant malignancy have been published. Here we report on a female patient with Kabuki syndrome and a c.2558_2559delCT germline variant in KMT2D who developed an embryonal rhabdomyosarcoma (ERMS) at 10 years. On tumor tissue we performed DNA-methylation profiling and exome sequencing (ES). Copy number analyses revealed aneuploidies typical for ERMS including (partial) gains of chromosomes 2, 3, 7, 8, 12, 15, and 20 and 3 focal deletions of chromosome 11p. DNA methylation profiling mapped the case to ERMS by a DNA methylation-based sarcoma classifier. Sequencing suggested gain of the wild-type KMT2D allele in the trisomy 12. Including our patient literature review identified 18 patients with Kabuki syndrome and a malignancy. Overall, the landscape of malignancies in patients with Kabuki syndrome was reminiscent of that of the pediatric population in general. Histopathological and molecular data were only infrequently reported and no report included next generation sequencing and/or DNA-methylation profiling. Although we found no strong arguments pointing towards KS as a tumor predisposition syndrome, based on the small numbers any relation cannot be fully excluded. Further planned studies including profiling of additional tumors and long term follow-up of KS-patients into adulthood could provide further insights.

Influence of growth hormone therapy on germinoma survivors

PURPOSE

Due to the effectiveness of growth hormone therapy (GHT), the number of cancer survivors receiving GHT has increased. Previous studies had indicated that GHT was not associated with the increasing risks of tumor recurrence and development with second neoplasm (SN) in cancer survivors. However, to date, research on those risks in germinoma survivors is still limited. The aim of this study is to evaluate the impact of GHT in relation to tumor recurrence and development with SN in pure germinoma survivors.

METHODS

This retrospective cohort study was approved by the Ethical Committee for Epidemiology of our institution. Seventy-three consecutive patients who underwent a biopsy of the lesion and were diagnosed with pure germinoma were retrospectively studied. They (median age, 15.0 years) were followed up more than 1 year after biopsy (median follow-up period, 14.3 years). The following data was obtained from the medical records of the patients: age, sex, preoperative magnetic resonance imaging findings, hormonal replacement, and events including tumor recurrence and/or SN.

RESULTS

In our patient series, 16 patients (21.9%) who were more likely to have neurohypophysial lesion and receive multiple hormonal therapies had received GHT. No significant differences in the rates of tumor recurrence and development with SN were observed between the patients who had and had not received GHT. Moreover, the recurrence-free survival and overall survival rates were not different between the patients who had and had not received GHT.

CONCLUSIONS

GHT did not increase the risks of tumor recurrence and development with SN in pure germinoma survivors.

Priapism as the first symptom of chronic myeloid leukemia: literature review and own clinical case report

Chronic myeloid leukemia is a ph-positive myeloproliferative disease, which is usually manifested by hyperleukocytosis and massive splenomegaly. Chronic myeloid leukemia is rare in childhood and adolescence, it accounts for 2 to 3 % of all leukemias cases. priapism is a rare manifestation of chronic myeloid leukemia and is an urgent urological condition that requires timely treatment to prevent long-term complications, in particular, erectile dysfunction.This review presents the literature information about priapism as the first sign of chronic myeloid leukemia, as well as the first description in the Russian literature of a clinical case of priapism in a 9-year-old patient with chronic myeloid leukemia.

Diagnosis and treatment of adult Langerhans cell histiocytosis in the rib: a case report and literature review

BACKGROUND

Langerhans cell histiocytosis (LCH) is a rare proliferative disease caused by the proliferation of Langerhan's cells and aggregation in multiple organs. Rib involvement is extremely rare and easily misdiagnosed. The biologic behavior of LCH is largely unknown, and it is of utmost importance to differentiate it from tuberculosis and tumors. Herein, we present a male adult diagnosed with Langerhans cell histiocytosis of the rib which was successfully treated with surgery.

CASE DESCRIPTION

This study retrospectively reports a rare case of rib-only LCH in a 34-year-old male patient who complained of persistent stabbing pain in the left chest and back for 45 days. The pain increased after bending, and was accompanied by chest tightness, shortness of breath, and night sweats. The patient denied any family history of LCH. CT showed an isolated mass on the left chest wall invading the seventh posterior rib. The diagnosis was confirmed by immunohistochemical staining and pathological analysis. The immunohistochemistry showed VIM (+), Ki-67 (+30%), CD1a (+), CD 68 (+) and S-100 (+). After surgical resection, the patient was followed up for more than 5 years without recurrence or complication. In addition, we reviewed and summarized 11 reported LCH cases with rib involvement, in which patients were either asymptomatic, or reported chest or back pain. Surgical resection was the main therapy in each case, and after 4-63 months of follow up, all patients were disease-free.

CONCLUSIONS

This case presents a rare instance of adult LCH in the rib. Pathological typical Langerhans cells and positive protein S100, CD1a, and CD207 are the key evidences for LCH, and surgical resection is currently an effective therapy with satisfactory outcomes.

FLT3LG and IFITM3P6 consolidate T cell activity in the bone marrow microenvironment and are prognostic factors in acute myelocytic leukemia

Acute myelocytic leukemia (AML) is a malignancy of the stem cell precursors of the myeloid lineage. CD4+ and CD8+ T cells play pivotal roles in influencing AML progression but are functionally suppressed in the bone marrow microenvironment. We aimed to find hub genes related to T cell exhaustion and suppression, thereby providing evidence for immunotherapy. In this study, gene transcriptome expression data from TCGA and TARGET databases were utilized to find key genes. Firstly, CIBERSORT immune cell infiltration algorithm and WGCNA method were used to identify CD4+ and CD8+ T cells-related genes. Univariate and multivariate cox regression analyses were then introduced to construct the overall survival prognosis model and included hub genes. The ESTIMATE and ssGSEA scoring methods were used to analyze the correlation between the hub genes and immune activity. Single-cell transcriptome analysis was applied to detect the immune cells expressing hub genes, hence, to detect exact mechanisms. Consequently, FLT3LG and IFITM3P6 were determined to be positively correlated with patients’ overall survival and microenvironment immune activity. Further study suggested FLT3-FLT3LG and IFITM3P6-miR-6748-3p-CBX7 signaling axes were involved in CD4+ and CD8+ T cells activation. This may be one of the mechanisms of T cells suppression in AML.

Pediatric Precursor B-Cell Lymphoblastic Malignancies: From Extramedullary to Medullary Involvement

B-cell lymphoblastic lymphoma (BCP-LBL) and B-cell acute lymphoblastic leukemia (BCP-ALL) are the malignant counterparts of immature B-cells. BCP-ALL is the most common hematological malignancy in childhood, while BCP-LBL accounts for only 1% of all hematological malignancies in children. Therefore, BCP-ALL has been well studied and treatment protocols have changed over the last decades, whereas treatment for BCP-LBL has stayed roughly the same. Clinical characteristics of 364 pediatric patients with precursor B-cell malignancies were studied, consisting of BCP-LBL (n = 210) and BCP-ALL (n = 154) patients. Our results indicate that based on the clinical presentation of disease, B-cell malignancies probably represent a spectrum ranging from complete isolated medullary disease to apparent complete extramedullary disease. Hepatosplenomegaly and peripheral blood involvement are the most important discriminators, as both seen in 80% and 95% of the BCP-ALL patients and in 2% of the BCP-LBL patients, respectively. In addition, we show that the overall survival rates in this cohort differ significantly between BCP-LBL and BCP-ALL patients aged 1−18 years (p = 0.0080), and that the outcome for infants (0−1 years) with BCP-LBL is significantly decreased compared to BCP-LBL patients of all other pediatric ages (p < 0.0001).

Pediatric acute myeloid leukemia patients with KMT2A rearrangements: a single-center retrospective study

PURPOSE

Pediatric acute myeloid leukemia (AML) with KMT2A rearrangements has a very different prognosis. Poor outcomes cannot be avoided even after hematopoietic stem cell transplantation. In order to investigate the prognosis and efficacy, we conducted a retrospective analysis.

PATIENTS AND METHODS

We retrospectively analyzed a total of 32 children with KMT2A rearrangements AML treated in our hospital between January 2015 and February 2021.

RESULTS

The proportion of patients with KMT2A-rearranged in the medium-risk group of overall survival (OS) and event-free survival (EFS) was 100%. No differences in OS, EFS and cumulative incidence of relapse (CIR) were detected between the haploidentical hematopoietic stem cell transplantation (haplo-HSCT) and full matched HSCT (P = 0.289, P = 0.303, P = 0.303). Acute graft-versus-host disease (aGVHD) was often detected in the haplo-HSCT cohort, while full matched HSCT had no obvious aGVHD, assessed as≤1 grade (P < 0.05). Patients in the medium-risk pediatric group could acquire 100% OS and EFS only after chemotherapy. There was no significant difference in OS, EFS and CIR between full matched HSCT and haploidentical transplantation in pediatric AML with KMT2A rearrangements, but full matched HSCT seemed to have a lower death rate. The severity of aGVHD in the full matched HSCT was less than that in the haploidentical transplantation group.

CONCLUSION

The primary choice of donor can be HLA-matched sibling donors or matched unrelated donors for children with AML with KMT2A rearrangements, and the secondary choice can be haploid donors.

Hypothalamic syndrome

Hypothalamic syndrome (HS) is a rare disorder caused by disease-related and/or treatment-related injury to the hypothalamus, most commonly associated with rare, non-cancerous parasellar masses, such as craniopharyngiomas, germ cell tumours, gliomas, cysts of Rathke's pouch and Langerhans cell histiocytosis, as well as with genetic neurodevelopmental syndromes, such as Prader-Willi syndrome and septo-optic dysplasia. HS is characterized by intractable weight gain associated with severe morbid obesity, multiple endocrine abnormalities and memory impairment, attention deficit and reduced impulse control as well as increased risk of cardiovascular and metabolic disorders. Currently, there is no cure for this condition but treatments for general obesity are often used in patients with HS, including surgery, medication and counselling. However, these are mostly ineffective and no medications that are specifically approved for the treatment of HS are available. Specific challenges in HS are because the syndrome represents an adverse effect of different diseases, and that diagnostic criteria, aetiology, pathogenesis and management of HS are not completely defined.

Incidence and survival of haemophagocytic lymphohistiocytosis: A population-based cohort study from England

BACKGROUND

Haemophagocytic lymphohistiocytosis (HLH) is a rare hyper-inflammatory condition with poor outcomes.

OBJECTIVES

Few population-based estimates of the incidence and survival in adults exist. We aimed to provide these data for England.

METHODS

We used population-based linked data from primary care, secondary care, cancer registries and mortality databases in England to identify people diagnosed with HLH between 1 January 2000 and 31 December 2016. We calculated annual incidence rates by age and sex, modelled change in incidence over time with Poisson regression, calculated overall 1-year survival using Kaplan-Meier methods and estimated adjusted hazard ratios (HRs) of death using a Cox proportional hazards model.

RESULTS

We identified 214 patients with HLH. The reported age and sex-adjusted incidence increased twofold over the period, from around one to around two per million. Incidence was highest in those below 1 year (14.6 per million) and ≥75 years (2.2 per million), and lowest in those aged 15-44 years (0.8 per million). One-year survival varied by age and sex from 77% (95% confidence interval [CI] 63%-86%) in those <15 years to 30% (95% CI 14%-49%) in those ≥75. In patients with haematological cancer, the adjusted HR for death was 2.60 (95% CI 1.45-4.66) compared to patients with no malignant or rheumatological disease.

CONCLUSION

The incidence of HLH diagnosis in England has increased between 2000 and 2016 and occurs in all ages with varying underlying diseases. One-year survival varies substantially, being particularly poor in those aged over 75 years and those with haematological malignancy.

Soluble Sema4D Level Is Positively Correlated with Sema4D Expression in PBMCs and Peripheral Blast Number in Acute Leukemia

Semaphorin 4D (Sema4D) is highly expressed in various cancers and leukemia. It is involved in the development of acute leukemia. A high level of soluble Sema4D is also present in the plasma of acute leukemia patients. However, it remains unknown whether Sema4D is associated with the clinical characteristics of acute leukemia. In this study, Sema4D expression was examined in peripheral blood mononuclear cells (PBMCs) and bone marrow mononuclear cells (BMMCs) of patients with acute leukemia, and it was highly expressed in the PBMCs of B-acute lymphoblastic leukemia (ALL), T-ALL, and acute myeloid leukemia (AML) patients and in the BMMCs of B-ALL and AML patients but not in the BMMCs of T-ALL patients. Sema4D expression was higher in the PBMCs of T-ALL patients than in the PBMCs of B-ALL or AML patients. In addition, Sema4D expression in BMMCs was reduced in B-ALL patients during the chemotherapy process. It was lower in remission patients than in newly diagnosed and patients without remission. In acute leukemia, soluble Sema4D level in serum is positively correlated with Sema4D expression in PBMCs, leukocyte number, and peripheral blast number. Those results suggest that the levels of Sema4D and its soluble form are associated with acute leukemia development and may be regarded as a potential biomarker in pediatric acute leukemia.

Liver transplantation in a child with liver cirrhosis caused by langerhans cell histiocytosis: a case report

Background

Langerhans cell histiocytosis (LCH) is a rare condition that has a variety of clinical manifestations. But LCH in children localized only in the hepatobiliary system is unusual.

Case presentation.

Here we reported a rare case of a 2-year-old boy who was serendipitously found to have elevated liver enzymes while undergoing treatment of a perianal abscess. After a period of earlier conservative treatment in another hospital, the perianal abscess had resolved but the levels of liver enzymes were still rising slowly. The child was then referred to our institution for a definitive diagnosis. After laboratory tests, imaging and pathological examinations, a diagnosis of liver cirrhosis and sclerosing cholangitis was established, although the cause was unclear. Subsequently, living-donor liver transplantation was performed due to deterioration in liver function. Following successful liver transplantation, a diagnosis of LCH localized only within the hepatobiliary system was finally confirmed, based on additional pathological and imaging investigation. Additionally, the BRAF V600E mutation in this patient was also confirmed. The child has now recovered without evidence of LCH recurrence.

Conclusions

LCH localized only within the hepatobiliary system is unusual. The presence of unexplainable sclerosing cholangitis and liver cirrhosis in any child should raise the suspicion of LCH.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12887-021-03090-4.

Acute lymphoblastic leukemia in infants: A quarter century of nationwide efforts in Japan

Acute lymphoblastic leukemia (ALL) with KMT2A gene rearrangement (KMT2A-r) in infants is a biologically and clinically unique disease and one of the most difficult to cure forms of pediatric leukemia. Multicenter clinical trials have been carried out in Japan since the mid-1990s by introducing allogeneic hematopoietic stem cell transplantation (HSCT) in first remission, which led to a modest improvement in outcome of infants with KMT2A-r ALL. Because of the emerging evidence that HSCT does not benefit every infant with KMT2A-r ALL, the Japanese Pediatric Leukemia/Lymphoma Study Group trial MLL-10 introduced risk stratification using age and presence of central nervous system leukemia, and introduced intensive chemotherapy, including high-dose cytarabine in early consolidation; indication of HSCT was restricted to the patients with high-risk features. The trial resulted in excellent 3-year event-free survival of 66.2% (standard error, 5.6%) and overall survival of 83.9% (standard error, 4.3%) for 75 patients with KMT2A-r ALL recruited between 2011 and 2015. This Japanese experience and the results of the infant ALL trials worldwide suggest the importance of introducing effective therapy in the early phase of therapy, thus clearing minimal residual disease as rapidly as possible. However, further improvement in outcome is unlikely with conventional treatment approaches. Introduction of biology-driven novel agents and/or immunotherapies through international collaboration would be key solutions to overcome the disease.

Cancer among children, adolescents and young adults in the Hokushin region, Japan, between 2010 and 2015

Adolescents and young adults with cancer encounter age-related challenges. Cancer treatment and support are not always tailored to the needs of each patient due to difficulty in the collection of accurate data. The present study aimed to investigate cancer among children and adolescents and young adults in the four adjacent prefectures of Japan (Toyama, Ishikawa, Fukui and Nagano) by analyzing data from a unique regional cancer database. We retrieved and analyzed the data of pediatric and adolescent and young adult patients aged between 0 and 39 years at cancer diagnosis (including carcinoma in situ), which was registered in the Hokushin Ganpro database between 2010 and 2015. A total of 5718 cases (1571 males and 4147 females) were identified during this period. The overall male-to-female ratio was 1:2.6. There was no distinct difference in the number of cancer cases per 100 000 population between males and females until 19 years of age. The difference became more pronounced after 20 years of age. The number of cancer cases (per 100 000 population) in the 0-14-, 15-19-, 20-29- and 30-39-year age groups was estimated to be 13.4, 14.5, 44.0 and 101.5, respectively. Carcinomas were the most common type of cancer in the adolescents and young adults (15-39 years) population (74%), whereas they were not the predominant cancer type in the pediatric (0-14 years) population. Although further research is needed to understand the needs of adolescents and young adults with cancer, we believe that our findings will help guide efforts to improve the management strategy for adolescents and young adults with cancer.

Current status of intensive end-of-life care in children with hematologic malignancy: a population-based study

Background

Adult patients with hematologic malignancies are less likely to receive palliative care and more likely to accept intensive anti-cancer treatments until end-of-life than those with solid tumors, but limited data are available regarding the quality of end-of-life care (EOLC) for children with hematologic malignancies. To improve the quality of EOLC for children with hematologic malignancies, the aims of this study were (i) to compare intensive EOLC between children with hematologic malignancies and those with solid tumors; and (ii) to describe factors associated with intensive EOLC in children with hematologic malignancies.

Methods

We retrospectively reviewed 0- to 18-year-old patients with cancer, who died in hospital between April 2012 and March 2016 in Japan using the Diagnosis Procedure Combination per-diem payment system. Indicators of intensive inpatient EOLC were defined as intensive care unit admission, cardiopulmonary resuscitation (CPR), intubation and/or mechanical ventilation, hemodialysis, or extra-corporeal membrane oxygenation in the last 30 days of life, or intravenous chemotherapy in the last 14 days. We determined factors associated with intensive EOLC using regression models. Data regarding use of blood transfusion were also obtained from the database.

Results

Among 1199 patients, 433 (36%) had hematological malignancies. Children with hematologic malignancies were significantly more likely than those with solid tumors to have intubation and/or mechanical ventilation (37.9% vs. 23.5%), intensive care unit admission (21.9% vs. 7.2%), CPR (14.5% vs. 7.7%), hemodialysis (13.2% vs. 3.1%) or extra-corporeal membrane oxygenation (2.5% vs. 0.4%) in their last 30 days, or intravenous chemotherapy (47.8% vs. 18.4%; all P < .01) within their last 14 days of life. Over 90% of children with hematological malignancies received a blood transfusion within the last 7 days of life. For hematological malignancies, age under 5 years was associated with CPR and ≥ 2 intensive EOLC indicators. Longer hospital stays had decreased odds of ≥ 2 intensive EOLC indicators.

Conclusion

Children with hematologic malignancies are more likely to receive intensive EOLC compared to those with solid tumors. A younger age and shorter hospital stay might be associated with intensive EOLC in children with hematologic malignancies.

Transport Characteristics of 6-Mercaptopurine in Brain Microvascular Endothelial Cells Derived From Human Induced Pluripotent Stem Cells

The likelihood of reoccurrence of acute lymphoblastic leukemia is influenced by the cerebral concentration of the therapeutic agent 6-mercaptopurine (6-MP) during treatment. Therefore, it is important to understand the blood-brain barrier (BBB) transport mechanism of 6-MP. The purpose of this study was to characterize this mechanism using human induced pluripotent stem cell-derived microvascular endothelial cells (hiPS-BMECs). The permeability coefficient of 6-MP across hiPS-BMECs monolayer in the basal-to-apical direction (B-to-A) was significantly greater than that in the opposite direction (A-to-B). The inhibition profiles of 6-MP transport in the A-to-B direction were different from those in the B-to-A direction. Transport in the A-to-B direction was mainly inhibited by adenine (an inhibitor of equilibrative nucleobase transporter 1; ENBT1), while transport in the B-to-A direction was significantly reduced by inhibitors of multidrug resistance-associated proteins (MRPs), especially zaprinast (an MRP5 inhibitor). Immunocytochemical analyses demonstrated the expression of ENBT1 and MRP5 proteins in hiPS-BMECs. We confirmed that the cellular uptake of 6-MP is decreased by ENBT1 inhibitors in hiPS-BMECs and by knockdown of ENBT1 in hCMEC/D3 cells. These results suggest that ENBT1 and MRP5 make substantial contributions to the transport of 6-MP in hiPS-BMECs and hCMEC/D3 cells.

A clinical approach to parasellar lesions in the transition age

Many reviews have summarised the pathology and management of the parasellar region in adult patients, although an analysis of these aspects in the transition years, from puberty onset to the age of peak bone mass, has been lacking. A comprehensive search of English-language original articles, published from 2000 to 2020, was conducted in the MEDLINE database (December 2019 to March 2020). We selected all studies regarding epidemiology, diagnosis and management of the following parasellar lesions: germinoma, craniopharyngioma, Langerhans cell histiocytosis, optic glioma, hypothalamic hamartoma, tuber cinereum hamartoma, cranial chordoma, Rathke cleft cyst, hypophysitis and hypothalamitis during the transition age from childhood to adulthood. In the present review, we provide an overview of the principal parasellar lesions occurring in the transition age. Symptoms are usually a result of the mass effect of the lesions on nearby structures, as well as anterior pituitary deficits. Diabetes insipidus occurs frequently in these patients. In this age group, pubertal developmental disorders may be more evident compared to other stages of life. Parasellar lesions in the transition age mostly include neoplastic lesions such as germinomas, hamartomas, optic gliomas, craniopharyngiomas Langerhans cell histiocytosis and chordomas, and rarely inflammatory lesions (hypophysitis, hypothalamitis). There are limited data on the management of parasellar lesions in the transition age. Endocrine evaluation is crucial for identifying conditions that require hormonal treatment so that they can be treated early to improve the quality of life of the individual patient in this complex age range. The clinical approach to parasellar lesions involves a multidisciplinary effort.

In-Hospital Management Might Reduce Induction Deaths in Pediatric Patients With Acute Lymphoblastic Leukemia: Results From a Japanese Cohort

Induction deaths (ID) remain a critical issue in the treatment of pediatric patients with acute lymphoblastic leukemia (ALL). The reported rate of ID in this population is 1% or higher. We speculate that this proportion might be lower in Japan because of mandatory hospitalization during induction therapy to manage complications. We retrospectively analyzed the incidence of ID among children with ALL enrolled in 4 Japanese study groups between 1994 and 2013. Among 5620 children, 41 (0.73%) cases of ID were noted. The median age was 6.5 years; 24 children were female, and 7 had T-cell ALL. Infection was the most common cause of ID (n=22), but the incidence (0.39%) was lower than that reported in western countries. Mortality within 48 hours from the onset of infection was low, comprising 25% of infection-related deaths. The incidence of infections caused by Bacillus species was low. Only 1 patient died because of Aspergillus infection. Fatal infections mostly occurred during the third week of induction therapy. Our findings suggest that close monitoring, stringent infection control, and immediate administration of appropriate antibiotics through hospitalization might be important strategies in reducing the rate of infection-related ID in pediatric patients with ALL.

A risk-stratified therapy for infants with acute lymphoblastic leukemia: a report from the JPLSG MLL-10 trial

The prognosis for infants with acute lymphoblastic leukemia (ALL), particularly those with KMT2A gene rearrangement (KMT2A-r), is dismal. Continuous efforts have been made in Japan to investigate the role of hematopoietic stem cell transplantation (HSCT) for infants with KMT2A-r ALL, but improvement in outcome was modest. In the Japanese Pediatric Leukemia/Lymphoma Study Group MLL-10 trial, infants with ALL were stratified into 3 risk groups (low risk [LR], intermediate risk [IR], and high risk [HR]) according to KMT2A status, age, and presence of central nervous system leukemia. Children’s Oncology Group AALL0631 modified chemotherapy with the addition of high-dose cytarabine in early intensification was introduced to KMT2A-r patients, and the option of HSCT was restricted to HR patients only. The role of minimal residual disease (MRD) was also evaluated. Ninety eligible infants were stratified into LR (n = 15), IR (n = 19), or HR (n = 56) risk groups. The 3-year event-free survival (EFS) rate for patients with KMT2A-r ALL (IR + HR) was 66.2% (standard error [SE], 5.6%), and for those with germline KMT2A (KMT2A-g) ALL (LR), the 3-year EFS rate was 93.3% (SE, 6.4%). The 3-year EFS rate was 94.4% (SE, 5.4%) for IR patients and 56.6% (SE, 6.8%) for HR patients. In multivariable analysis, female sex and MRD ≥0.01% at the end of early consolidation were significant factors for poor prognosis. Risk stratification and introduction of intensive chemotherapy in this study were effective and were able to eliminate HSCT for a subset of infants with KMT2A-r ALL. Early clearance of MRD seems to have translated into favorable outcomes and should be incorporated into risk stratifications in future trials. This trial was registered at the University Hospital Medical Information Network Clinical Trials Registry (UMIN-CTR) as #UMIN000004801.

Comparison of child and family reports of health-related quality of life in pediatric acute lymphoblastic leukemia patients after induction therapy

BACKGROUND

This study aims at determining the health-related quality of life (HRQOL) of children with acute lymphoblastic leukemia (ALL) after the induction therapy, assessing the agreement between child self-reports and family proxy-reports HRQOL, and determining the factors related to this agreement, especially child age, family attendance, and children's social relationships beyond the family.

METHODS

We analyzed questionnaire data (2012-2017) from the Japanese Pediatric Leukemia/Lymphoma Study Group's clinical study (ALL-B12). Participants were children with B-cell precursor ALL aged 5-18 and their family members, who mostly took care of the child during hospitalization. Participants answered the Pediatric Quality of Life Inventory™ (PedsQL™) Generic Core Scales (PedsQL-G), and Cancer Module (PedsQL-C) to measure pediatric HRQOL. We calculated the differences between child self-reported and family proxy-reported subscale scores along with intraclass correlation coefficients (ICC). We conducted multiple regression analyses according to all participant pairs and age groups (young children, school age, and adolescents), with ICCs for all PedsQL-G subscales (ICC-G) and all PedsQL-C subscales (ICC-C) as the outcome variables.

RESULTS

Five hundred twenty-two pairs of children and their families were analyzed. We observed a moderate level of agreement on most PedsQL subscales between child self-reports and family proxy-reports; however, worry had the weakest agreement for all PedsQL subscales (ICC = .32, 95% confidence interval = .24-.40). The agreement of ICC-C was positively related to family attendance in the hospitalization, only for the young children group (B = .185, p = .003).

CONCLUSIONS

We observed some differences between child self-reports and family proxy-reports of HRQOL of children with ALL. Both child self-reports and family proxy-reports captured HRQOL in the induction therapy. We suggest that attending to young children's hospitalization affects the level of agreement between reports on their HRQOL.

Clinical features of children with polycythemia vera, essential thrombocythemia, and primary myelofibrosis in Japan: A retrospective nationwide survey

Background

Philadelphia-negative (Ph-negative) myeloproliferative neoplasms (MPNs), including polycythemia vera (PV), essential thrombocythemia (ET), and primary myelofibrosis (PMF), are exceptionally rare during childhood. Thus, clinical features of pediatric Ph-negative MPNs remain largely unknown. This study was therefore performed to address this.

Methods

We performed a retrospective study to collect clinical information of children diagnosed with Ph-negative MPNs from 2000 to 2016 using questionnaires in qualified institutions in Japan. The results obtained from the questionnaire survey were then combined with those from the national registry data.

Results

Among 50 children identified, five had PV, 44 had ET, and one had PMF. Median age at diagnosis was 14.0, 9.0, and 0 years, respectively. Male to female ratio was 4:1, 21:23, and 1:0, respectively. Detection rates of the JAK2 V617F variant were 0/5 in PV and 9/39 in ET. Frequencies of complications, such as thrombosis and subsequent leukemia, were lower than complication frequencies in adults. We identified two children who developed subsequent leukemia, which has not been reported previously, and one of them died.

Conclusion

This is the first nationally representative survey of pediatric Ph-negative MPNs. Given its rarity, an international collaboration with comprehensive genetic analyses might be needed to fully elucidate the clinical and genetic features.

Langerhans cell histiocytosis confined to extrahepatic bile duct causing sclerosing cholangitis in child: a case report

Background

Langerhans cell histiocytosis (LCH) is an abnormal accumulation of Langerhans cells in various organs that sometimes induces organ dysfunction. LCH can affect the liver, resulting in sclerosing cholangitis and biliary cirrhosis. However, liver and bile duct involvement is usually observed in the disseminated form of LCH. We herein report a rare case of LCH localized only in the extrahepatic bile duct that resulted in severe liver cirrhosis.

Case presentation

A 3-year-old boy with elevated liver enzymes, obstructive jaundice, and dilation of the common bile duct was referred to our institution. Contrast-enhanced computed tomography showed atrophy of the right hepatic lobe, relative hypertrophy of the left hepatic lobe, choledocholiths, and biliary debris extensively with biliary duct dilation. Magnetic resonance cholangiopancreatography revealed dilation of the intrahepatic and extrahepatic bile ducts and multiple choleliths in the gallbladder and common bile duct. Laparoscopic cholecystectomy, intraoperative cholangiography, liver biopsy, and gastrointestinal fiberscopy were performed. A liver specimen showed severe biliary cirrhosis due to sclerosing cholangitis. The patient then underwent living-donor liver transplantation because of severe liver cirrhosis 3 months after the first surgery. The common bile duct was not suitable for duct-to-duct anastomosis and was resected because of severe inflammation. Histologic sections of the common bile duct showed histiocytic cell proliferation. Immunohistochemistry revealed histiocytoses that were positive for Langerin, S-100 protein, and CD1a. However, no histiocytic cell proliferation was noted in the liver tissue. The definitive diagnosis was LCH localized to the extrahepatic bile duct. LCH in the extrahepatic bile duct seemed to cause sclerosing cholangitis. The patient was discharged uneventfully 2 months after living-donor liver transplantation.

Conclusions

LCH localized to the extrahepatic bile duct is extremely rare; however, LCH can still affect the extrahepatic bile ducts on occasion. LCH should be considered as a differential diagnosis if pediatric patients show the presence of sclerosing cholangitis.

Long-term outcome of childhood acute myeloid leukemia: A 10-year retrospective cohort study

Acute Myeloid Leukemia (AML) in children is a serious disease. With a proper treatment, a long-term survival rate above 50% is typical. Before 2010, all the AML patients died in our hospital, and abandonment rate was more than 50%. The aims of this study are to explore the long-term outcome of newly childhood acute myeloid patients treated at Hue Central Hospital from 2010 to 2019.A retrospective study was conducted on 98 children with AML who admitted Hue Central Hospital from January 2010 to December 2019. The diagnosis was confirmed by morphological FAB criteria, cytochemistry and immunophenotype. Patients were treated with using modified AML 7-3 Regimen. Social supports were provided to patients/families. A total of 98 children with AML were analyzed with mean age of 5.6 years ranging from 3 months to 15 years. The male to female ratio was 1.8:1. The overall complete remission rate after induction were 82.6%). Patients accounted for 46 (46.9%) had relapses which occurred in during chemotherapy n=27 (27,6%), after finishing chemotherapy n=19(19,4%). Overall survival at 3 years were 23.2%. The event-free survival at 3 years were 20.2%o. Abandonment cases were 4 (4.1%). During the period study, abandonment has been reduced successfully with holistic strategies such as financial support, managing family group, providing education, early follow-up of patients who missed appointments and free accommodation near hospital for patients/families. However, with a high rate patient achieved complete remission after induction phase (82.6%), but the overal survival and event-free survival at 3 years were still low in my hospital (23.2 % and 20.2% respectively). It reflected that it was very difficult to treat successfully AML in lowand middle-income countries. We are considering the way how to improve the quality treatment for childhood acute myeloid leukemia in my hospital.

Palliative care utilization in hospitalized children with cancer

BACKGROUND

There is growing evidence that palliative care (PC) is associated with increased quality of life in children with cancer. Despite increasing recommendations in support of PC to improve pediatric oncology care, little is known about its patterns of use.

METHODS

We analyzed the 2005-2011 National Inpatient Sample, a representative, cross-sectional sample of US hospital admissions. Our study cohort comprised 10 960 hospitalizations of children with cancer and high in-hospital mortality risk. Survey-weighted regression models were constructed to determine associations of person- and hospital-level characteristics with PC involvement and healthcare costs.

RESULTS

Overall, 4.4% of hospitalizations included PC involvement. In regression models invoking stepwise variable selection, a shorter length of stay (PC vs no PC; mean: 23.9 vs 32.6 days), solid cancer (solid vs hematologic vs brain cancer; PC use: 7.4% vs 2.8% vs 5.5%), and older age (PC vs no PC; mean: 10.2 vs 8.9 years) were associated with PC use. PC utilization was also associated with lower overall and daily hospital costs.

CONCLUSIONS

One in 20 pediatric inpatients with cancer and high mortality risk receives PC, with differential utilization by socio-economic groups. These results have significant implications for public health resource allocation and the delivery of pediatric PC as high-value care. Future research should focus on the development of new tools to help physicians assess when PC is appropriate for their patients.

Bortezomib-containing therapy in Japanese children with relapsed acute lymphoblastic leukemia

Outcomes of children treated for relapsed acute lymphoblastic leukemia (ALL) remain poor. Bortezomib (BZM), a proteasome inhibitor, has shown promising activity against lymphoid malignancies. We conducted a phase I study to evaluate the safety and tolerability of multidrug chemotherapy including BZM in Japanese children with relapsed ALL. Three of five children with relapsed ALL enrolled in the study between November 2014 and April 2016 were evaluated. BZM (1.3 mg/m²) was administered on days 8, 11, 15, and 18 of multidrug induction chemotherapy. Pharmacokinetic studies were performed. Age at study entry was 5, 7, and 7 years old, respectively. Two patients had hyperdiploid B-precursor ALL, and one had T cell ALL. Although all patients experienced grade 3-4 hematologic toxicity and grade 3 elevation of aminotransferases, no dose-limiting toxicities were observed. The maximum tolerated dose was defined as 1.3 mg/m². Peripheral neuropathy and respiratory complications were not observed. Complete remission was achieved in all three patients. The mean maximum plasma concentration and area under the concentration-time curve was 74.0 ng/mL and 73.9 ng h/mL, respectively. Thus, adding BZM to 5-drug induction chemotherapy appears safe and well-tolerated in Japanese children with relapsed ALL.

Cervical langerhans cell histiocytosis mimicking cervical tuberculosis: A Case report

RATIONALE

Langerhans cell histiocytosis (LCH) involving adult cervical vertebrae is relatively rare clinically.

PATIENT CONCERNS

An 18-year-old male patient exhibited a 1-month history of neck pain, restricted neck mobility, and numbness and weakness of both upper limbs. The patient reported no pain at other sites, exhibited no fever or night sweats, and was unable to recall any recent injury.

DIAGNOSES

On the basis of the radiological features of the lesion and laboratory tests, there was a high possibility that the patient had a tuberculosis lesion. Postoperative GeneXpert and Mycobacterium tuberculosis (MTB) culture results showed MTB negative. Postoperative pathological results showed: (Cervical 4 vertebrae) LCH.

INTERVENTIONS

Our department did an anterior approach operation. The patient was treated with prednisone combined with vincristine after operation.

OUTCOMES

The patient was discharged from the hospital with complete remission of cervical pain and rapid relief of neurological symptoms.

LESSONS

Computed tomography-guided biopsy of lesion tissue must be performed when a suspected infection occurs in young patients. If possible, the lesion tissue obtained during the operation should be cultured and pathologically examined for early diagnosis.

Characteristics and outcomes of patients with essential thrombocythemia or polycythemia vera diagnosed before 20 years of age: a systematic review

Although it is well known that myeloproliferative neoplasms occur in younger patients, few large cohorts of such patients have been reported. Thus, our knowledge about circumstances of diagnosis, outcome and treatment is limited, especially for children and young adults. We therefore performed a systematic review of cases, published since 2005, concerning patients aged below 20 years at the time of diagnosis of essential thrombocythemia or polycythemia vera. We identified 396 cases of essential thrombocythemia and 75 of polycythemia vera. The median age at diagnosis was 9.3 and 12 years, respectively, and females constituted 57.6% and 45% of the groups, respectively. Half of the patients were asymptomatic at diagnosis. The proportion of so-called triple negativity was high: 57% in essential thrombocythemia and 73% in polycythemia vera. The incidence of thrombosis during the follow-up was 9.3% in patients with polycythemia vera and less, 3.8%, in those with essential thrombocythemia. Venous events were predominant (84.2%), with hemorrhagic episodes being rarer (<5%). The risk of evolution also seemed low (2% to myelofibrosis and no reports of acute leukemia), but the median follow-up was only 50 months. Survival curves were not available. Half of the patients received an antithrombotic drug and 40.5% received a cytoreductive drug. All data should be analyzed with care because of the proportion of missing data (10.7% to 74.7%). This review highlights interesting points concerning this population of young patients with myeloproliferative neoplasms, including that such patients were identified as negative for all common driver mutations, but also shows the need for larger contemporary cohorts with longer follow-up to assess the true prognosis of these patients.

Improvement of treatment outcome over 2 decades in children with acute myeloid leukemia

Background

The prognosis of pediatric acute myeloid leukemia (AML) has recently improved. This study aimed to describe the epidemiology, changes in treatment strategies, and improvement of outcomes in Gwangju-Chonnam children with AML over 2 decades.

Methods

Medical records of 116 children with newly diagnosed AML were retrospectively reviewed for demographic characteristics, prognostic groups including cytogenetic risks, treatment protocols, and survival rates over the periods between 1996 and 2005 (Period I, N=53), and 2006 and 2015 (Period II, N=38).

Results

The annual incidence of AML has decreased with reduced pediatric population. The 5-year Kaplan-Meier (K-M) estimated overall survival (OS) and event-free survival (EFS) rates in 110 AML patients were 53.2±5.1% and 43.8±5.1%, respectively. The 5-year OS rate significantly improved during period II (70.3±7.0%) as compared to that during period I (40.0±6.8%) (P =0.001). The 5-year OS was not significantly different among cytogenetic risk groups (P =0.11). Fifty-eight patients underwent hematopoietic stem cell transplantation (HSCT). The K-M 5-year estimated survival for transplanted patients was 53.7±7.0%, while that for chemotherapy-only patients was 30.1±9.1% (P =0.014). Among the prognostic factors, treatment modality was the only independent factor. The chemotherapy-only group had a relative risk of 2.06 for death compared with the transplantation group (P=0.015).

Conclusion

The survival of Korean children with AML has improved to a level comparable with that of developed countries over 2 decades, owing to a change in induction strategy, better supportive care with economic growth, refinement of HSCT techniques including a better selection of patients based on prognostic groups, and stem cell donor selection.

Treatment and biology of pediatric acute lymphoblastic leukemia

Acute lymphoblastic leukemia (ALL) is the most common pediatric malignancy. In the past ALL was intractable but now the survival probability is as high as 80-90%. Improved supportive care, treatment stratification based on relapse risk, biological features of leukemic cells, and optimization of treatment regimens by nationwide and international collaboration have contributed to this dramatic improvement. While including traditional risk factors (e.g. age and leukocyte count at diagnosis), the treatment has been modified based on biological characteristics (aneuploidy and translocation) and treatment response (assessed by minimal residual disease). Treatment for pediatric ALL typically consists of induction therapy with steroids, vincristine, and asparaginase with or without anthracycline, followed by multi-agent consolidation including high-dose methotrexate and re-induction therapy. After consolidation, less intensive maintenance therapy is required for 1-2 years to maintain event-free survival. Recently, using advanced genomic analysis technology, novel sentinel genomic alterations that may provide more precise stratification or therapeutic targets, were identified. Moreover, in the last decade germline variations have been recognized as similarly important contributors to understanding the etiology and sensitivity of ALL to treatment. A more individualized approach based on genomic features (somatic and germline) and treatment response, the introduction of newly developed agents such as molecular targeted drugs or immunotherapy, and social support including long-term follow up are required for further improvement.

Allogeneic Hematopoietic Stem Cell Transplantation for Adolescents and Young Adults with Acute Myeloid Leukemia

Few reports have focused on adolescent and young adult (AYA) patients with acute myeloid leukemia (AML) treated with hematopoietic stem cell transplantation (HSCT). We performed a retrospective analysis based on data obtained from a Japanese nationwide registration database to compare HSCT outcomes in AYA patients with AML with those in children with AML. An analysis of the 2973 patients with de novo AML who received allogeneic HSCT from 1990 to 2013 showed inferior 5-year overall survival (OS) (54% versus 58%, P <.01) and increased treatment-related mortality (TRM) (16% versus 13%, P = .02) in AYA patients. Multivariate analysis for both OS and TRM showed a significant negative impact on AYAs. However, the negative impact of older age lost its significance in an additional analysis focusing on 1407 recent transplant recipients with high-resolution HLA typing (2000 to 2013). Finally, we analyzed the impact of transplantation center type on HSCT outcomes in 317 adolescent patients (15 to 18 years old) and found no difference in outcomes between patients treated at a pediatric or an adult hospital. Higher age was a strong predictive factor for inferior OS resulting from increased TRM, which can be eliminated with better donor selection using high-resolution HLA typing.

Genotyping NUDT15 can predict the dose reduction of 6-MP for children with acute lymphoblastic leukemia especially at a preschool age

The pharmacokinetics among children has been altered dynamically. The difference between children and adults is caused by immaturity in things such as metabolic enzymes and transport proteins. The periods when these alterations happen vary from a few days to some years after birth. We hypothesized that the effect of gene polymorphisms associated with the dose of medicine could be influenced by age. In this study, we analyzed 51 patients with childhood acute lymphoblastic leukemia (ALL) retrospectively. We examined the associations between the polymorphism in NUDT15 and clinical data, especially the dose of 6-mercaptopurine (6-MP). Ten of the patients were heterozygous for the variant allele in NUDT15. In patients under 7 years old with NUDT15 variant allele, the average administered dose of 6-MP was lower than that for the patients homozygous for the wild-type allele (P=0.04). Genotyping of NUDT15 could be a beneficial to estimate the tolerated dose of 6-MP for patients with childhood ALL, especially at a preschool age in Japan. Furthermore, the analysis with stratification by age might be useful in pharmacogenomics among children.

Phase 1 study of clofarabine in pediatric patients with relapsed/refractory acute lymphoblastic leukemia in Japan

A phase 1 study was conducted to evaluate the safety, pharmacokinetics (PK), efficacy and pharmacogenetic characteristics of clofarabine in seven Japanese pediatric patients with relapsed/refractory acute lymphoblastic leukemia (ALL). Patients in Cohort 1 received clofarabine 30 mg/m(2)/day for 5 days, followed by 52 mg/m(2)/day for 5 days in subsequent cycles. Cohort 2 patients were consistently treated with 52 mg/m(2)/day for 5 days. No more than six cycles were performed. Every patient had at least one ≥Grade 3 adverse event (AE). AEs (≥Grade 3) related to clofarabine were anaemia, neutropenia, febrile neutropenia, thrombocytopenia, alanine aminotransferase increased, aspartate aminotransferase increased, haemoglobin decreased, and platelet (PLT) count decreased. C max and AUC of clofarabine increased in a dose-dependent fashion, but its elimination half-life (T 1/2) did not appear to be dependent on dose or duration of treatment. Clofarabine at 52 mg/m(2)/day shows similarly tolerable safety and PK profiles compared to those in previous studies. No complete remission (CR), CR without PLT recovery, or partial remission was observed. Since clofarabine is already used as a key drug for relapsed/refractory ALL patients in many countries, the efficacy of clofarabine in Japanese pediatric patients should be evaluated in larger study including more patients, such as by post-marketing surveillance.

Prognostic Impact of Intensified Maintenance Therapy on Children With Advanced Lymphoblastic Lymphoma: A Report From the Japanese Pediatric Leukemia/Lymphoma Study Group ALB-NHL03 Study

BACKGROUND

Childhood advanced lymphoblastic lymphoma (LBL) has a favorable outcome with an event-free survival (EFS) rate of over 80% in response to treatment strategies for acute lymphoblastic leukemia (ALL). However, no progress has been made in this outcome over the past 10 years.

PROCEDURE

We conducted the first nationwide prospective study of childhood advanced LBL to assess the efficacy and safety of ALL-directed therapy with an intensified maintenance phase. We omitted local radiotherapy including prophylactic cranial radiotherapy except for patients with initial central nervous system disease. The total duration of the treatment was 24 months.

RESULTS

For the 136 patients analyzed in this study, 5-year overall survival (OS) was 82.9% and 5-year EFS was 77.9%. Thirty events were observed and 14 occurred before the initiation of intensified maintenance phase. Of 14 events, nine were observed as mediastinal enlargement. There was no significant difference in outcome when stratified according to gender or by immunophenotype. The 5-year EFS according to clinical stage in patients with T-cell LBL (T-LBL) was 70.6% for stage III and 88.9% for stage IV (P = 0.037).

CONCLUSIONS

Our first nationwide study provided about 80% cure rate with only one case of toxic death in childhood advanced LBL. However, our intensified maintenance therapy could not improve the survival outcome. There was a trend of better EFS in Japanese patients with T-LBL stage IV than T-LBL stage III.

Leukostasis in Children and Adolescents with Chronic Myeloid Leukemia: Japanese Pediatric Leukemia/Lymphoma Study Group

BACKGROUND

The details of leukostasis in children and adolescents with chronic myeloid leukemia (CML) are unknown. This study determined the characteristics of leukostasis in children and adolescents with CML.

PROCEDURE

A total of 256 cases from a retrospective study of patients with CML conducted by the Japanese Pediatric Leukemia/Lymphoma Study Group from 1996 to 2011 were analyzed, and of these, 238 cases were evaluated in this study.

RESULTS

Leukostasis was diagnosed in 23 patients (9.7%). The median leukocyte count and spleen size below the left costal margin in cases with leukostasis were significantly higher and larger when compared to those in cases without leukostasis (458.5 × 10(9) /l vs. 151.8 × 10(9) /l (P < 0.01), and 13 vs. 5 cm (P < 0.01), respectively). Leukostasis occurred with ocular symptoms in 14 cases, priapism in four cases, and dyspnea, syncope, headache, knee pain, difficulty hearing, and aseptic necrosis of the femoral head in one case each. One case had two leukostasis symptoms simultaneously. Three cases were diagnosed before imatinib became available. Five cases received special treatment, and in the remaining 15 cases, all of these symptoms resolved after treatment with imatinib.

CONCLUSIONS

This retrospective study represents the largest series of children and adolescents in which leukostasis of CML has been reported. Our data provide useful insight into the characteristics of leukostasis in recent cases of children and adolescents with CML.

Primary T-cell lymphoblastic lymphoma in the middle ear

T-cell lymphoblastic lymphoma (T-LBL) is a highly aggressive lymphoma characterized by precursor T-cell malignancy and lymphadenopathy or mediastinal involvement. We present the case of an 11-year-old boy with a diagnosis of middle ear T-LBL, which manifested as a headache, hearing loss and peripheral facial paralysis. The child was given intensive chemotherapy and had a complete response. To our knowledge, this is the first case reported in the literature of T-LBL originating in the middle ear. This case aims to help clinicians to be vigilant about the possibility of primary lesions at atypical sites in some special diseases.

Acute myeloid leukemia in children: Current status and future directions

Acute myeloid leukemia (AML) accounts for 25% of pediatric leukemia and affects approximately 180 patients annually in Japan. The treatment outcome for pediatric AML has improved through advances in chemotherapy, hematopoietic stem cell transplantation (HSCT), supportive care, and optimal risk stratification. Currently, clinical pediatric AML studies are conducted separately according to the AML subtypes: de novo AML, acute promyelocytic leukemia (APL), and myeloid leukemia with Down syndrome (ML-DS). Children with de novo AML are treated mainly with anthracyclines and cytarabine, in some cases with HSCT, and the overall survival (OS) rate now approaches 70%. Children with APL are treated with an all-trans retinoic acid (ATRA)-combined regimen with an 80-90% OS. Children with ML-DS are treated with a less intensive regimen compared with non-DS patients, and the OS is approximately 80%. HSCT in first remission is restricted to children with high-risk de novo AML only. To further improve outcomes, it will be necessary to combine more accurate risk stratification strategies using molecular genetic analysis with assessment of minimum residual disease, and the introduction of new drugs in international collaborative clinical trials.

Recent progress in the treatment of infant acute lymphoblastic leukemia

Treatment of infants with acute lymphoblastic leukemia (ALL), especially those with mixed lineage leukemia (MLL) rearrangement (MLL-r), which account for approximately 80% of cases, is still a major challenge for pediatric hematologists and oncologists worldwide. Continuing efforts by collaborative clinical study groups in Europe, North America, and Japan have rescued approximately half of the MLL-r ALL patients with intensive chemotherapy with or without allogeneic hematopoietic stem cell transplantation. Recent progress has clarified the unique mechanism of MLL-r ALL: the aberrant methylation and histone modifications via DOT1L and other related molecules by MLL fusion proteins lead to leukemogenetic gene expression, thus to overt leukemia. In order to overcome this dismal subtype of ALL, novel targeted therapy based on leukemia biology is urgently needed. Due to the extreme rarity of the disease, collaboration between the study groups in Europe (Interfant), North America (Children's Oncology Group), and Japan (Japanese Pediatric Leukemia/Lymphoma Study Group) is under way.

Chronic lymphocytic inflammation with pontine perivascular enhancement responsive to steroids (CLIPPERS) after treatment for Hodgkin's lymphoma

Chronic lymphocytic inflammation with pontine perivascular enhancement responsive to steroids (CLIPPERS) is a rare central nervous system (CNS) disorder with distinct radiological features. However, CLIPPERS may mimic CNS lymphoma, and several cases in which CLIPPERS occurred premonitory to CNS lymphoma have been reported. We report a 31-year-old man presenting with progressive gait ataxia and the characteristic MRI features of CLIPPERS. He was diagnosed with stage II Hodgkin's lymphoma at the age of 15, and we considered the possibility of newly emerged CNS lymphoma occurring in the immunosuppressive condition after the treatment of Hodgkin's lymphoma. Histological findings showed no evidence of CNS lymphoma and the neurological symptoms were resolved by steroids. Although CLIPPERS developed in the reverse order in this case, CLIPPERS should be considered in different diagnosis for CNS lymphoma.

Early Diagnosis and Monitoring of Neurodegenerative Langerhans Cell Histiocytosis

Background

Neurodegenerative Langerhans Cell Histiocytosis (ND-LCH) is a rare, unpredictable consequence that may devastate the quality of life of patients cured from LCH. We prospectively applied a multidisciplinary diagnostic work-up to early identify and follow-up patients with ND-LCH, with the ultimate goal of better determining the appropriate time for starting therapy.

Methods

We studied 27 children and young adults with either ND-LCH verified by structural magnetic resonance imaging (MRI) (group 1) or specific risk factors for (diabetes insipidus, craniofacial bone lesions), but no evidence of, neurodegenerative MRI changes (group 2). All patients underwent clinical, neurophysiological and MRI studies.

Results

Seventeen patients had MRI alterations typical for ND-LCH. Nine showed neurological impairment but only three were symptomatic; 11 had abnormal somatosensory evoked potentials (SEPs), and five had abnormal brainstem auditory evoked potentials (BAEPs). MR spectroscopy (MRS) showed reduced cerebellar NAA/Cr ratio in nine patients. SEPs showed sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) for predicting ND-LCH of 70.6% (95%CI, 44.0%-89.7%), 100% (69.2%-100%), 100% (73.5%-100%), and 66.7% (38.4%-88.2%), respectively. Repeated investigations in group 1 revealed increasingly abnormal EP parameters, or neurological examination, or both, in nine of fifteen patients while MRI remained unchanged in all but one patient.

Conclusion

A targeted MRI study should be performed in all patients with risk factors for ND-LCH for early identification of demyelination. The combined use of SEPs and careful neurological evaluation may represent a valuable, low-cost, well-tolerated and easily available methodology to monitor patients from pre-symptomatic to symptomatic stages. We suggest a multidisciplinary protocol including clinical, MRS, and neurophysiological investigations to identify a population target for future therapeutic trials.