Yasuhiro Okamoto

Yasuhiro Okamoto
Kagoshima University | Kadai · Department of Pediatrics

MD

About

182
Publications
7,575
Reads
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2,087
Citations
Introduction
Yasuhiro Okamoto currently works at the Department of Pediatrics, Kagoshima University. Yasuhiro does research in Oncology, Hematology and Cancer Research. Their current project is 'Toxicity'.
Additional affiliations
April 2015 - present
Kagoshima University
Position
  • Professor (Associate)
July 2000 - June 2002
St. Jude Children's Research Hospital
Position
  • Fellow
June 1990 - May 1991
The University of Tokushima
Position
  • Medical Doctor

Publications

Publications (182)
Article
We herein describe the first pediatric case of an internal mammary artery (IMA) aneurysm caused by a median sternotomy. He was a 2-year-old with tricuspid atresia who underwent an extracardiac conduit Fontan procedure. On the 36th postoperative day, an asymptomatic left IMA aneurysm was detected via contrast computed tomography, which was successfu...
Article
Full-text available
We herein report a 13-year-old boy with a chief complaint of abdominal pain and a palpable mass. Contrast-enhanced computed tomography (CT) scan showed an abdominal bulky tumor involving the ascending colon causing severe stenosis, with multiple abdominal lymph node metastases detected by positron emission tomography (PET)-CT. Laparoscopic radical...
Preprint
The pathogenesis of cyclophosphamide (CY)-induced cardiotoxicity remains unknown, and methods for its prevention have not been established. To elucidate acute structural changes in myocardial cells and pathways leading to myocardial damage in mice treated with high-dose CY, we performed detailed pathological analyses of myocardial tissue obtained f...
Article
Persistent cloaca involves fusion of the bladder, vagina, and rectum into a single duct called the common duct. Although its pathogenesis remains unclear, it has been associated with hyperchloremic metabolic acidosis. Herein, we present the case of a neonatal girl with high-confluence type variant of persistent cloaca treated with vesicostomy (Bloc...
Article
Drug resistance is a major problem in treatment with nelarabine, and its resolution requires elucidation of the underlying mechanisms. We established two nelarabine-resistant subclones of the human T-cell lymphoblastic leukemia cell line CCRF-CEM. The resistant subclones showed changes in the expression of several genes related to nelarabine intrac...
Article
Full-text available
We report the first early infantile case with paroxysmal atrioventricular block (PAVB). He was born at 33 weeks of gestation and, from 23 days of age, he had paroxysmal bradycardia repeatedly. His heart rate at rest was 150 to 170/minute and there was often some paroxysmal sinus bradycardia. Paroxysmal complete atrioventricular block was observed t...
Article
Background: T-cell acute lymphoblastic leukemia (T-ALL) accounts for approximately 10-15% or 25% of cases of pediatric or adolescent and young adult (AYA) ALL, respectively. The use of pediatric protocols can improve outcomes in AYA T-ALL. Furthermore, nelarabine (NEL) has been shown to be effective for patients with relapsed or refractory T-ALL. T...
Article
MLL (KMT2A) rearrangements are among the most frequent chromosomal abnormalities that occur in acute myeloid leukemia (AML). Mutational landscapes in KMT2A-rearranged AML have been reported; however, most studies are missing data at relapse. Therefore, matched diagnostic and relapse samples were analyzed in this study, and the clonal evolution patt...
Article
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Escherichia albertii is a recently recognized human enteropathogen that is closely related to Escherichia coli. As E. albertii sometimes causes outbreaks of gastroenteritis, rapid strain typing systems, such as the O- and H-serotyping systems widely used for E. coli, will be useful for outbreak investigation and surveillance. Although an O-genotypi...
Preprint
Background: Patients with strong pulmonary vascular occlusive lesions are at risk of developing postoperative pulmonary hypertension (PH). We aimed to evaluate preoperative right ventricular (RV) function in patients with ventricular septal defect (VSD) who required cardiac surgery during infancy and consequently developed postoperative PH and to d...
Preprint
Full-text available
Purpose: Patients with strong pulmonary vascular occlusive lesions are at risk of developing postoperative pulmonary hypertension (PH). We aimed to evaluate preoperative right ventricular (RV) function in patients with ventricular septal defect (VSD) who required cardiac surgery during infancy and consequently developed postoperative PH and to dete...
Article
Full-text available
Children with acute myeloid leukemia (AML) commonly develop extramedullary disease (EMD), which comprises central nervous system (CNS) lesions and myeloid sarcoma (MS). In this retrospective analysis, we aimed to determine the effect of EMD on the outcomes of allogeneic hematopoietic cell transplantation (HCT) in 678 pediatric patients with de novo...
Article
Herein, we describe a 14-year-old female patient with B-cell precursor acute lymphoblastic leukemia who relapsed in early consolidation. Minimal residual disease-negative complete remission was obtained after 1 cycle of inotuzumab ozogamicin therapy. She underwent HLA-haploidentical peripheral blood stem cell transplantation after a myeloablative c...
Article
We herein report a 10‐month‐old female infant with a 4‐month history of diarrhea with electrolyte abnormalities and growth impairment. A 4‐cm right adrenal tumor was detected by computed tomography. No metastasis or accumulation on I¹²³‐metaiodobenzylguanidine scintigraphy was recognized in the tumor. A vasoactive intestinal peptide‐secreting neuro...
Article
Herein, we describe a 13-year-old male adolescent who had chronic thrombocytopenia since infancy. In this case, X-linked thrombocytopenia (XLT) was suspected owing to a family history of chronic thrombocytopenia and small-sized platelets. Moreover, the patient was refractory to immunoglobulin therapy. The Wiskott-Aldrich syndrome protein (WASP) exp...
Article
In an analysis of 653 cases of acute lymphoblastic leukemia associated with Down syndrome (DS-ALL) collected from clinical research groups worldwide, the 8-year disease-free survival for DS-ALL was 64%, which was worse than the 81% for non-DS-ALL during the same period. This could be because DS-ALL has less hyperdiploidy and ETV6-RUNX1 abnormalitie...
Article
Background: The appropriateness of allogeneic hematopoietic stem cell transplantation (HSCT) in children and adolescents with leukemia in whom complete remission is not possible remains unclear. This retrospective analysis aimed to investigate the outcomes associated with HSCT, and the risks of HSCT in children and adolescents with nonremission ac...
Article
We retrospectively analyzed nationwide records of 163 Fanconi anemia (FA) patients [aplastic anemia (AA), n = 118; myelodysplastic syndrome (MDS), n = 30; acute leukemia, n = 15] who underwent first allogeneic hematopoietic stem cell transplantation (HSCT) between 1987 and 2015 in Japan. An alternative donor was used in 119 (73%) patients, and 160...
Article
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...
Article
Full-text available
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...
Article
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Fludarabine/cyclophosphamide-based conditioning regimens are standard in bone marrow transplantation (BMT) for acquired bone marrow failure in children, however, graft failure may occur. Using the data from a nationwide transplantation registry, we compared the outcomes of children aged <16 years with acquired aplastic anemia and refractory cytopen...
Article
Full-text available
Japan Children’s Cancer Group (JCCG) is the only national clinical research group for childhood cancer in Japan, which was established in December 2014. In this paper, the JCCG describes its efforts in Japan and Asia and shares its current goals for enhancing the effective treatment of childhood cancer. International collaborative research is neces...
Article
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We describe the case of a 2-year-old girl with a primary left upper mediastinal neuroblastoma with bone metastasis. She underwent autologous peripheral blood stem cell transplantation following chemotherapy with high-dose busulfan-melphalan. On day 61, she developed pulmonary hypertension with generalized fatigue and hypoxemia. On day 91, she was d...
Preprint
Full-text available
Purposes: To determine the health-related quality of life (HRQOL) of children with acute lymphoblastic leukemia (ALL) during induction therapy, clarify the agreement between child self-reported and family proxy-reported HRQOL, and examine the related factors of HRQOL, especially child age, family attendance, and children’s social relationships outs...
Article
Although concurrent bacteremia in siblings is rare, serotype 24F Streptococcus pneumoniae was isolated from the blood of twin 1-year-old girls within a 3-day interval, supporting the high invasive potential of this serotype. As the prevalence of childhood serotype 24F-invasive pneumococcal diseases increases in Europe and the Western Pacific Region...
Article
Objective: Pediatric acute myeloid leukemia (AML) with KMT2A rearrangement is detected in 15-20% of all pediatric AML patients and is associated with adverse outcomes even after allogeneic hematopoietic stem cell transplantation (HSCT). To investigate outcomes and prognostic factors, we investigated 90 pediatric AML patients with KMT2A rearrangeme...
Article
Background: Ploidy is a highly significant prognostic factor for pediatric acute lymphoblastic leukemia (ALL). Children with hypodiploid ALL have poor outcomes despite current intensive chemotherapy. Little has been investigated focusing on hypodiploid ALL among Japanese children. Methods: We retrospectively collected clinical data of hypodiploi...
Article
Full-text available
Allogeneic hematopoietic stem cell transplantation (HSCT) can be used to treat children with refractory acute myeloid leukemia (AML). This retrospective analysis aimed to describe the outcomes and risk factors in such children. Data were collected through the nation-wide registry program in Japan. A total of 417 AML (median age: 13 years) patients...
Article
Lymphatic malformation (LM) is a congenital disorder resulting from an abnormal development of lymphatic vessels. LM may result in problems of cosmesis and functional impairment, including airway compression. An 11-year-old girl was referred to our department with increasing dysphagia caused by a large left cervical LM with a long history of treatm...
Article
Pediatric anaplastic large-cell lymphoma (ALCL), which is characterized by strong expression of CD30, is usually responsive to multidrug chemotherapy. Brentuximab vedotin (BV) which is an anti-CD30 antibody-drug conjugate is a promising drug with effects on relapsing or refractory ALCL. However, its effects may not be sufficient for the central ner...
Article
We report the first case of liver abscess due to Sterigmatomyces halophilus. Because this pathogen grows poorly in culture medium without added salts, it was identified by sequencing analysis targeting the rRNA gene internal transcribed spacer (ITS) region. This method could be useful for pathogens that cannot be cultured using standard methods.
Article
The correct name of the first author should be ‘‘Ryu Yanagisawa’’, and not ‘‘Ryu Yanagaisawa’’ as given in the original publication of the article.
Article
Background Fatal adverse effects or relapse can occur with excessive or insufficient busulfan exposure in hematopoietic stem cell transplantation. As busulfan is mainly metabolized by glutathione S‐transferase (GST), we investigated the influence of GST gene polymorphisms on busulfan pharmacokinetics in Japanese pediatric patients. Methods Blood s...
Article
Epstein–Barr virus (EBV)-associated hemophagocytic lymphohistiocytosis (HLH) is highly prevalent in Japan. To date, no standard treatment for EBV–HLH has been established owing to the diversity in treatment response and the difficulty in assessing prognostic factors. The present prospective study recruited 27 children with EBV–HLH who were also par...
Article
Here, we report the case of a 9-year-old girl with acute myeloid leukemia (AML) developed from systemic mastocytosis (SM). She experienced bladder and rectal disturbance due to an extramedullary nodule in the paraspinal region of the sacrum. Cytogenetic and genetic analyses of leukemic cells revealed the KIT D816Y mutation besides t (8;21) (q22:q22...
Article
Recent advances in intensive chemo- and immunotherapy have contributed to the outcome of hemophagocytic lymphohistiocytosis (HLH); however, the prognosis of HLH in children differs by HLH subtype. In Japan, secondary HLH, particularly Epstein–Barr virus-associated HLH (EBV-HLH), is the most common HLH subtype. The prognosis of HLH has improved in r...
Article
Purpose It is difficult to decide whether children with leukemia who could not achieve complete remission (CR) after relapse or primary induction failure should undergo transplantation. Nonetheless, allogeneic hematopoietic stem cell transplantation (HSCT) is a possible approach for refractory acute leukemia including acute lymphoblastic leukemia (...
Article
Purpose It is difficult to decide whether children with leukemia who could not achieve complete remission (CR) after relapse or primary induction failure should undergo transplantation. Nonetheless, allogeneic hematopoietic stem cell transplantation (HSCT) is a possible approach for refractory acute myeloid leukemia (AML). Despite being refractory...
Article
We examined 3 pediatric patients with bilineal acute leukemia. Patient 1 with B-cell acute lymphoblastic leukemia (ALL) and acute myelogenous leukemia (AML) with B-ALL dominance responded well to prednisolone and ALL-type induction therapy. Patients 2 and 3 with T-ALL and AML with AML dominance responded poorly to prednisolone. Patient 2 was resist...
Article
B-cell precursor acute lymphoblastic leukemia is the most common pediatric malignancy, but its treatment needs to be modified to cause low acute toxicity and few late complications with a high cure rate. In this trial, we will stratify patients with B-cell precursor acute lymphoblastic leukemia into standard, intermediate and high risk groups accor...
Article
Infantile hemangiomas (IH) are the most common in the head and neck region.1 They can occur anywhere in the skin, however, urethral hemangiomas are very rare. We describe a case report of a three years old boy with extensive lesions of IH in the anterior urethra. Urethral IH were disappeared during one year of oral administration of propranolol tho...
Article
Weight gain is often observed in children with acute lymphoblastic leukemia (ALL) who undergo chemotherapy including steroids. An increase in body mass index (BMI)-standard deviation score (SDS) during induction therapy is reported as a risk factor for obesity after treatment. However, risk factors of an increase in BMI-SDS during induction therapy...
Article
We describe the case of a 23-month-old male infant with Epstein-Barr virus (EBV)-associated lymphoproliferative disorder, which mimicked the recurrence of EBV-associated hemophagocytic lymphohistiocytosis. Chemotherapy with dexamethasone, etoposide, and cyclosporine resolved fever, hepatosplenomegaly, and pancytopenia. However, on day 81 of illness...
Article
This retrospective study compared the use of thiamylal plus pentazocine (TP) to ketamine plus midazolam (KM) in children with leukemia who were undergoing bone marrow aspiration and/or intrathecal chemotherapy. A total of 268 procedures in 35 children with leukemia were retrospectively analyzed for efficacy and adverse events. All procedures were s...
Article
Metaiodobenzylguanidine (MIBG) scans are sensitive testing tools for neuroblastoma. Persistent positive MIBG scans in patients with stage 3 neuroblastoma have previously been found to indicate maturation rather than regression. We assessed the significance of this finding in stage 4 neuroblastoma in the present study. Fifteen consecutive pediatric...
Article
Full-text available
Background The dose-limiting toxic effect of cyclophosphamide (CY) is cardiotoxicity. The pathogenesis of myocardial damage is poorly understood, and there is no established means of prevention. In previous studies, we suggested that for CY-induced cardiotoxicity, whereas acrolein is the key toxic metabolite, carboxyethylphosphoramide mustard (CEPM...
Article
Full-text available
The early-onset form of carnitine palmitoyltransferase (CPT) II deficiency has severe outcomes; patients typically die during the newborn period. We report a case of neonatal-onset CPT II deficiency with prolonged survival, exceeding 24months. The patient was successfully treated by continuous hemodialysis (CHD), which enabled her to overcome repea...
Article
Background Osteoporosis can lead to spontaneous fractures in adults with cerebral palsy (CP). Undercarboxylated osteocalcin (ucOC) is a useful marker for vitamin K insufficiency in osteoporosis. The primary objective of this study was to determine the effect of vitamin K2 on bone mineral density (BMD) in adults with CP and vitamin K insufficiency....
Article
Drug-induced cardiomyopathy can be life-threatening in patients with cancer. Our objective was to explore early detection of drug-induced cardiomyopathy in children with cancer. We enrolled pediatric outpatients diagnosed with cancer between 2012 and 2013. In addition, we recruited pediatric outpatients in good general condition without cardiac dis...
Article
We report the case of a 1-year-old girl with stage 4 neuroblastoma who developed massive hemothorax due to tumor invasion before treatment. She presented with tachypnea, worsening anemia, and oxygen desaturation. Hemothorax was diagnosed based on chest radiography, ultrasonography, and diagnostic thoracic puncture results. High neuron-specific enol...
Article
Full-text available
Cat scratch disease (CSD) is an infectious disease caused by Bartonella henselae. Atypical clinical presentations of CSD include prolonged fever and multiple hepatosplenic lesions, although these are rare. Furthermore, multiple renal lesions are extremely rare in CSD. The patient was an 11-year-old Japanese girl who had a prolonged fever of unknown...
Article
Background: Nelarabine has been used for the treatment of T-cell malignancies including T-acute lymphoblastic leukemia (T-ALL)/T-lymphoblastic lymphoma. However, the mechanisms that underlie the susceptibility or resistance to nelarabine have not been fully elucidated. The aim of this study was to determine the significance of nelarabine transport...
Article
Full-text available
We herein describe a 7-year-old male with refractory acute myeloid leukemia who relapsed 9 months after bone marrow transplantation from human leukocyte antigen (HLA) -identical sibling. He received 2 cycles of FLAG chemotherapy, however, complete remission was not obtained. In addition, sepsis due to viridans group streptococci occurred in 2 of 2...
Article
Lamotrigine (LTG) is an anti-epileptic drug and mood-stabilizing agent, whose adverse effects include skin rash and dizziness. Interactions with the immune system are rare, and only a few cases linking hypogammaglobulinemia to LTG treatment have been previously described. In this report, we describe a case in which a patient developed hypogammaglob...
Article
Full-text available
Recent studies revealed that a substantial proportion of patients with high-risk B-cell precursor acute lymphoblastic leukemia (BCP-ALL) harbor fusions involving tyrosine kinase and cytokine receptors, such as ABL1, PDGFRB, JAK2 and CRLF2, which are targeted by tyrosine kinase inhibitors (TKIs). In the present study, transcriptome analysis or multi...
Article
Posttransplantation lymphoproliferative disorder (PTLD) is associated with significant mortality in kidney transplant recipients. PTLD cases associated with poor prognostic factors that are refractory to reduction of immunosuppression generally require chemotherapy and immunotherapy. We present a patient with PTLD who achieved complete remission af...