Tatsuro Tajiri

• Doctor of Medicine
• Professor at Kyushu University

This study presents an innovative ultrasound-guided technique for central venous access in patients with venous occlusion, particularly in those requiring long-term parenteral nutrition (TPN). Conventional access points often become occluded, necessitating alternative methods for approaching the central vein. A retrospective review of three patient...

Background Intractable vascular anomalies (VAs), including vascular tumors and venous, lymphatic, and mixed malformations, often have severe symptoms and a poor prognosis, highlighting the need for new treatments. We conducted a prospective trial of sirolimus (tablet and granule forms) for the treatment of VAs. Methods In this open‐label, single‐a...

Purpose Congenital mesoblastic nephromas (CMN) are histologically classified into classical, cellular, and mixed subtypes. Most cellular CMNs harbor ETV6-NTRK3 gene fusions, and classic and mixed CMNs harbor EGFR internal tandem duplications (EGFR-ITDs). Classic CMNs are considered benign, whereas recurrent or metastatic diseases occur in the cellu...

Purpose This study assessed the long-term impact of bile leak complications on the pediatric hepatoblastoma (HB) patients post-surgery. With HB predominantly affecting children under five, the increased survival rates necessitate a focus on the post-surgical complications, particularly concerning the effects of bile leaks. Methods A retrospective...

Background and study aims The aim of this study was to clarify the endoscopic characteristics of colorectal hamartomatous polyps, including solitary juvenile polyp (JP) and solitary Peutz-Jeghers polyp (PJP). Patients and methods We reviewed the clinicopathological and endoscopic findings of 151 colorectal polyps with a diagnosis of solitary JP or...

Purpose To ensure the safe prevalence of pediatric endoscopic surgery in Japan, a training curriculum should be established. In addition, the number of pediatric surgical cases is decreasing due to the decreasing birth rate in Japan, and it is necessary to clarify the number of surgical cases required for young pediatric surgeons to achieve autonom...

Background: Pediatric pancreatic tumors are rare and account for < 0.1% of all childhood cancers. The primary treatment for pancreatic tumors is surgical resection. However, because of the lack of knowledge regarding pediatric pancreatic tumors, no comprehensive treatment plans for pediatric pancreatic tumors have been developed. Aim: To compare...

Purpose: Congenital mesoblastic nephromas (CMN) are histologically classified into classical, cellular, and mixed subtypes. Most cellular CMNs harbor ETV6-NTRK3 gene fusions, and classic and mixed CMNs harbor EGFR internal tandem duplications (EGFR-ITDs). Classic CMNs are considered benign, whereas recurrent or metastatic diseases occur in the cell...

Purpose: In this study, we attempted to create skeletal muscle sheets made of Directly converted myoblasts (dMBs) with a nanogel scaffold on a biosheet using a mouse gastroschisis model. Methods: dMBs were prepared by the co-transfection of MYOD1 and MYCL into human fibroblasts. Silicon tubes were implanted under the skin of NOG/SCID mice, and bios...

Purpose In this study, we attempted to create skeletal muscle sheets made of directly converted myoblasts (dMBs) with a nanogel scaffold on a biosheet using a mouse gastroschisis model. Methods dMBs were prepared by the co-transfection of MYOD1 and MYCL into human fibroblasts. Silicon tubes were implanted under the skin of NOG/SCID mice, and biosh...

Purpose The study aimed to explore and describe the lives of patients with persistent cloaca (PC) from childhood to adulthood. Methods Semistructured interviews were conducted with nine adult patients with PC. Their experiences and thoughts regarding this disease were analyzed qualitatively and inductively. Results After classifying the experienc...

The development of innovative solutions, such as simulator training and artificial intelligence (AI)-powered tutoring systems, has significantly changed surgical trainees’ environments to receive the intraoperative instruction necessary for skill acquisition. In this study, we developed a new objective assessment system using AI for forceps manipul...

Background/purpose Living donor liver transplantation (LDLT) is vital for pediatric end-stage liver disease due to organ shortages. The graft-to-recipient weight ratio (GRWR) preoperatively measured predicts the outcomes of LDLT. We typically target between 0.8 and 3.0–4.0%, but the ideal GRWR remains controversial. We compared the outcomes of LDLT...

Purpose Megacystis microcolon intestinal hypoperistalsis syndrome (MMIHS) is defined as a congenital visceral myopathy with genetic mutations. However, the etiology and pathophysiology are not fully understood. We aimed to generate a gene leiomodin-1a (lmod1a) modification technique to establish a zebrafish model of MMIHS. Methods We targeted lmod...

Purpose We aimed to identify factors predicting the need for future liver transplantation (LT) at 18 years of age in patients with biliary atresia (BA). Methods BA patients with native liver survival at > 18 years of age were retrospectively reviewed. The clinical characteristics, outcomes, hepatobiliary function, and liver fibrosis markers of nat...

Background/Purpose Living donor liver transplantation (LDLT) is vital for pediatric end-stage liver disease due to organ shortages. The graft-to-recipient weight ratio (GRWR) preoperatively measured predicts the outcomes of LDLT. We typically target between 0.8% and 3.0–4.0%, but the ideal GRWR remains controversial. We compared the outcomes of LDL...

Purpose Megacystis microcolon intestinal hypoperistalsis syndrome (MMIHS) is defined as a congenital visceral myopathy with genetic mutations. However, the etiology and pathophysiology are not fully understood. We aimed to generate a gene leiomodin-1a (lmod1a) modification technique to establish a zebrafish model of MMIHS. Methods We targeted lmod...

(Purpose) We aimed to identify factors predicting the need for future liver transplantation (LT) at 18 years of age in patients with biliary atresia (BA). (Methods) BA patients with native liver survival at >18 years of age were retrospectively reviewed. The clinical characteristics, outcomes, hepatobiliary function, and liver fibrosis markers of...

Background We previously showed that total tumor resection enhances metastatic growth in a syngeneic metastatic mouse model of neuroblastoma. In this study, we further investigated which surgical factors contributed most to metastatic growth. Methods Tumor cells derived from MYCN transgenic mice were subcutaneously injected into wild-type mice. Mi...

Background We previously showed that total tumor resection enhances metastatic growth in a syngeneic metastatic mouse model of neuroblastoma. In this study, we further investigated which surgical factors contributed most to metastatic growth. Methods Tumor cells derived from MYCN transgenic mice were subcutaneously injected into wild-type mice. Mi...

Background Recently, reports of endoscopic approaches for neuroblastoma, ganglioneuroblastoma, and ganglioneuroma (peripheral neuroblastic tumor; PNTs) have been increasing. This study aimed to clarify the indications for endoscopic surgery for PNTs. Methods Pediatric patients who underwent endoscopic surgery for PNTs at our institution were inclu...

Background and Aim Even with advancement of medical technologies, liver transplantation still faces several major challenges. Hence, other treatment modalities are urgently needed for patients with end‐stage liver disease. Stem cells from human exfoliated deciduous teeth (SHED) was discovered to have highly proliferative and pluripotent properties;...

Background Gastroesophageal reflux (GER) disease (GERD) is a condition wherein GER causes troublesome symptoms that can affect daily functioning and/or clinical complications within the esophagus or other systems. To avoid this, patients with GERD often require treatment; hence, it is important to distinguish GER from GERD. Patients with GERD exhib...

Isolated hypoganglionosis (IHG) is histologically characterized by small numbers of myenteric ganglion cells and small myenteric ganglia; however, no numerical diagnostic criteria for IHG have been established. Therefore, this study aimed to develop quantitative pathologic criteria for IHG. We evaluated 160 resected intestinal tissue specimens from...

Purpose Survival rates of patients with high‐risk neuroblastoma are unacceptable. A time‐intensified treatment strategy with delayed local treatment to control systemic diseases has been developed in Japan. We conducted a nationwide, prospective, single‐arm clinical trial with delayed local treatment. This study evaluated the safety and efficacy of...

Gaucher disease (GD) is a lysosomal storage disorder caused by a deficiency in the GBA1 ‐encoded enzyme, β‐glucocerebrosidase . Enzyme replacement therapy is ineffective for neuronopathic Gaucher disease (nGD). High‐dose ambroxol has been administered as an alternative treatment for a group of patients with nGD. However, little is known about the c...

Severe obesity in young children prompts for a differential diagnosis that includes syndromic conditions. Rapid-Onset Obesity with Hypothalamic Dysfunction, Hypoventilation, and Autonomic Dysregulation (ROHHAD) syndrome is a potentially fatal disorder characterized by rapid-onset obesity associated with hypoventilation, neural crest tumors, and end...

Introduction Intractable lymphatic anomalies (LAs) include cystic lymphatic malformation (LM; macrocystic, microcystic, or mixed), generalized lymphatic anomaly, and Gorham–Stout disease. LAs can present with severe symptoms and poor prognosis. Thus, prospective studies for treatments are warranted. We conducted a prospective clinical trial of siro...

Simple Summary Tumor differentiation therapy using retinoids has a long history of clinical development and an established role as a part of the standard treatment for high-risk neuroblastoma. However, basic and clinical science related to this treatment is still immature in multiple respects. In the present review, we systematically expand on the...

Introduction Biliary atresia (BA) is a cholestatic hepatopathy caused by fibrosing destruction of intrahepatic and extrahepatic bile ducts, and its etiology has not been clearly revealed. In BA, liver fibrosis progression is often observed even after Kasai portoenterostomy (KPE), and more than half of cases require liver transplantation in their li...

Retinoids are vitamin A derivatives and include trans-retinoic acid, isotretinoin, tamibarotene, and bexarotene, all of which are currently available for clinical use. The clinical development of retinoid therapy for neuroblastoma has a history spanning more than four decades. The most promising agent is isotretinoin, which can contribute to improv...

Background/Purpose Whether Roux-en-Y hepatic jejunectomy (HJ) or duct-to-duct biliary reconstruction (DD) is more useful in pediatric living donor liver transplantation has not yet been fully investigated. Therefore, to assess the feasibility and safety of DD, we compared the surgical outcomes of DD to HJ. Methods We divided 45 patients, excluding...

Background Pseudoprogression and subsequent shrinkage of solid tumor foci are typical clinical processes and are seen in approximately 2–8% of cases during immune checkpoint inhibitor (ICI) treatment. Refractory/relapsed pediatric solid tumors including neuroblastoma (NB), however, are well-known to be highly resistant to ICI. In addition, in the c...

Background The aim of this study was to clarify the characteristics and outcomes of pediatric patients with solid pseudopapillary neoplasms (SPNs) who underwent pancreatectomy. Methods Pediatric patients with SPNs who underwent pancreatectomy at our institution between 1995 and 2020 were included in the study. Results During the period under revi...

Simple Summary Neuroblastoma (NB) is a common pediatric tumor, and less than 50% of children with high-risk (HR)-NB can achieve long-term survival. This is mainly due to a tumor relapse caused by the activation of therapy-resistant minimal residual disease (MRD). Several assays measuring different sets of MRD markers by quantitative PCR (qPCR) or d...

Background/Purpose: Whether Roux-en-Y hepatic jejunectomy (HJ) or duct-to-duct biliary reconstruction (DD) is more useful in pediatric living donor liver transplantation has not yet been fully investigated. Therefore, to assess the feasibility and safety of DD, we compared the surgical outcomes of DD to HJ. Methods: We divided 45 patients, excludin...

Hirschsprung disease (HSCR) and its associated disorders (AD-HSCR) often result in severe hypoperistalsis caused by enteric neuropathy, mesenchymopathy, and myopathy. Notably, HSCR involving the small intestine, isolated hypoganglionosis, chronic idiopathic intestinal pseudo-obstruction, and megacystis-microcolon-intestinal hypoperistalsis syndrome...

Abstract Background It has been hypothesized that the origin of early-onset endometriosis could be from endometrial mesenchymal stem cells (eMSCs) in neonatal uterine blood (NUB). There is no information on the possible mechanistic basis linking an association between NUB/neonatal endometrium and development of early-onset endometriosis. In this st...

Background/aim: Using the tyrosine hydroxylase (TH)-MYCN mouse neuroblastoma (NB) model, we have previously reported the accumulation of mouse mesenchymal stem cells (mMSCs) on tumors in vivo and the antitumor effect of mMSCs transfected with a small molecule (IFN-β) expression gene. In this study, we have developed novel MSCs secreting anti-disia...

Background: Gastrointestinal symptoms are one of the most common presentations of Coronavirus disease-19 (COVID-19), even in children. Higher rates of complicated appendicitis have been demonstrated in the era of the COVID-19 outbreak, and it has been recently suggested that acute appendicitis may occur as a complication of COVID-19. However, the...

Background: There is no standard timing for switching to surgical management for children with adhesive small bowel obstruction (ASBO) who initially receive conservative treatment. We hypothesized that an increased gastrointestinal drainage volume may indicate the need for surgical intervention. Methods: The study population included 150 episode...

Purpose: The aim of this study was to clarify the appropriate management after birth for congenital biliary dilatation (CBD, choledochal cyst) patients with a prenatal diagnosis. Method: Thirteen patients with a prenatal diagnosis of CBD who underwent liver biopsy during excision surgery were divided into two groups and retrospectively analyzed:...

Introduction Food protein-induced enterocolitis syndrome (FPIES) is a T-cell-mediated allergy that can occur in newborns and infants who are introduced to milk protein. Some of the serious complications of FPIES include necrotizing enterocolitis (NEC), massive bloody stools, and disseminated intravascular coagulation. Here we report a case of NEC c...

PurposeMouse IgG anti-disialoganglioside GD2 antibody-secreting mouse mesenchymal stem cells (anti-GD2-MSCs) were developed, and their anti-tumor effects were validated in an in vivo neuroblastoma mouse model.Methods Anti-GD2 antibody constructs were generated, incorporating FLAG-tagged single-chain fragment variables against GD2 fused to a linker...

Purpose This study aims to clarify the relationship between changes in skeletal muscle mass during treatment and prognosis of pediatric malignant solid tumors. Methods Patients with pediatric malignant solid tumors who were treated at Kyushu University Hospital from 2007 to 2017 were divided into two groups: the progression-free survival (PFS) gro...

Purpose The prenatal diagnosis of the stomach position in congenital diaphragmatic hernia (CDH) has been a reliable prognostic factor, but few studies have focused on the postnatal position. We therefore evaluated the significance of the nasogastric (NG) tube position just after birth. Methods The Japanese CDH Study Group database enrolled 1037 CD...

Background The leading pathology of biliary atresia (BA) is inflammatory and fibrous obstruction of extrahepatic bile duct, but the pathogenesis remains unclear. IL13 is a cytokine associated with allergies and inflammatory fibrosis, and periostin induces fibrogenesis by stimulation with IL13. We analyzed the involvement of IL13 and periostin in in...

Purpose The number of accessible central veins (CVs) affects the prognosis of patients with intestinal failure (IF). The loss of residual CVs should be avoided. We, therefore, evaluated the efficacy of a new CV catheter-exchange technique using a subcutaneous fibrous sheath (FS) in pediatric IF patients. Methods We retrospectively collected the CV...

Background: The leading pathology of biliary atresia (BA) is inflammatory and fibrous obstruction of extrahepatic bile duct, butthe pathogenesis remains unclear.IL13 is a cytokine associated with allergies and inflammatory fibrosis, and periostin induces fibrogenesis by stimulation with IL13. We analyzed the involvement of IL13 and periostin in inf...

Purpose The number of accessible central veins (CVs) affects the prognosis of patients with intestinal failure (IF). The loss of residual CVs should be avoided. We therefore evaluated the efficacy of a new CV catheter-exchange technique using a subcutaneous fibrous sheath (FS) in pediatric IF patients. Methods We retrospectively collected the CV c...

Purpose This study aims to clarify the relationship between changes in skeletal muscle mass during treatment and prognosis of pediatric malignant solid tumors. Methods Patients with pediatric malignant solid tumors who were treated at Kyushu University Hospital from 2007 to 2017 were divided into two groups: the progression-free survival (PFS) grou...

Purpose:The prenatal diagnosis of the stomach position in congenital diaphragmatic hernia (CDH) has been a reliable prognostic factor, but few studies have focused on the postnatal position. We therefore evaluated the significance of the nasogastric (NG) tube position just after birth. Methods: The Japanese CDH Study Group database enrolled 1037 CD...

Immaturity of ganglia (IG), is a rare entity of an allied disorder of Hirschsprung’s disease. We reviewed our IG cases to provide further pathological insight into IG. The clinical data and pathological findings of IG cases in our department from 2011 to 2020 were examined. Hematoxylin and eosin (HE) staining and immunostaining for HuC/D, BCL-2, SO...

Background: In November 2011, rotavirus (RV) vaccine was launched in Japan as a voluntary vaccination to prevent RV-associated gastroenterocolitis. We examined the characteristics of intussusception following RV vaccination in our two centers. Methods: We investigated intussusception patients <16 years old from January 2006 to September 2020. Pa...

Gastrointestinal bleeding or perforation following influenza infection is rare. We encountered a pediatric case of hemorrhagic duodenal ulcer following influenza A infection. The patient was a 1‐year and 4‐month‐old boy who was diagnosed with influenza A infection and treated with laninamivir octanoate. After inhalation, he had diarrhea, poor appet...

Objectives: Pyriform sinus cyst (PSC) and pyriform sinus fistula (PSF) is a rare congenital malformation that arises from the third or fourth branchial structure. In our study, we describe the safety and the utility of endoscopic electrocauterization against PSC/PSF. Methods: We retrospectively reviewed the records of patients who underwent endo...

Background Some neuroblastoma (NB) cases are suitable for minimally invasive surgery (MIS), but indication and technical issue are unclear. We assessed the current status of MIS for abdominal NB after mass screening period in Japan.Methods Preliminary questionnaires requesting the numbers of NB cases that underwent MIS from 2004 to 2016 were sent t...

Background: Core-needle biopsy (CNB) is used less frequently for the diagnosis of tumors in pediatric patients. In this report, the utility and safety of CNB for pediatric patients are described. Methods: The medical records of patients who underwent CNB at the Department of Pediatric Surgery, Kyushu University Hospital from April 2020 to Novemb...

Background Immaturity of ganglia (IG), an allied disorder of Hirschsprung disease (AD-HSCR), develops as neonatal ileus, but the dysmotility spontaneously resolves after several months. The diagnosis of IG using HE staining is often difficult. We herein report a new pathological finding of IG called the ‘palisading-like pattern’, which may be helpf...

Background In Japan, allogeneic hematopoietic stem cell transplantation is widely performed for recurrent neuroblastomas. This retrospective study aimed to investigate the prognosis of recurrent neuroblastoma in Japan and explore the effectiveness of allogeneic hematopoietic stem cell transplantation. Methods Clinical characteristics and data on t...

Paragangliomas (PGL) are extremely rare tumors, especially in children. While minimally invasive surgical techniques are well established in adult patients, the evidence in children is extremely limited. PGL have a rich blood flow and are located around large vessels; thus, operative exposure and resection are often difficult due to proximity to ma...

Neuroblastomas (NBs) exhibit broad and divergent clinical behaviors and tumor risk classification at diagnosis is crucial for the selection of an appropriate therapeutic strategy for each patient. The present study aimed to validate the clinical relevance of International Neuroblastoma Risk Group (INRG) prognostic and genomic markers in a Japanese...

Background Minimally invasive surgery (MIS) is appropriate for the treatment of some neuroblastomas (NBs); however, the indications and technical issues are unclear. This study aimed to clarify the current status of MIS for mediastinal NB in Japan. Methods Preliminary questionnaires requesting the numbers of neuroblastoma cases in which MIS was pe...

Background One of the most frequent complications after repair of esophageal atresia (EA) is gastroesophageal reflux disease (GERD). Although GERD associated with EA is well known to often require anti-reflux surgery, the predicting factors remain unclear. We retrospectively analyzed EA in our institute. Methods Among 65 children with EA treated i...

Background We previously reported the in vitro and in vivo antitumor effects of trametinib, a MEK inhibitor, on neuroblastoma with MAPK pathway mutations. As we observed eventual resistance to trametinib in our previous study, we evaluated the combination therapy of CA3, a YAP inhibitor, with trametinib, based on a recent report suggesting the pote...

Biliary atresia is an intractable disease whose details have yet to be elucidated. Kasai’s portoenterostomy (KPE) has been recommended to be performed within 60 days to improve jaundice. After KPE, the rate of jaundice disappearance is said to be 60%–70%. Liver transplantation is required if jaundice does not disappear. Even if jaundice disappears,...

Purpose We reported the in vitro and in vivo anti-tumor effects of trametinib, an MEK inhibitor, on neuroblastoma. However, long-term trametinib administration for bulky tumors failed to prevent local relapse. In this study, we established a local minimal residual disease (L-MRD) model to develop an optimal clinical protocol. Methods We prepared a...

Purpose The majority of relapsed neuroblastomas have mitogen-activated protein kinase (MAPK) pathway activating mutations. We previously showed the in vitro and in vivo anti-tumor effects of MAPK/ERK kinase (MEK) inhibitors in MAPK-activated neuroblastoma. We herein assessed the correlation between MAPK activation and the prognosis in neuroblastoma...

Background/aim: Malignant rhabdoid tumor (MRT) is a rare, aggressive neoplasm found in young children, caused by inactivation of a single gene, SNF5 (INI1, SMARCB1). MRT cases with multifocal tumors at diagnosis are categorized as synchronous MRT, often with a germline mutation of SNF5. The aim of this study was to establish new models useful in c...

In the October 2018 issue of International Journal of Clinical Oncology.

PURPOSE We report here the outcomes and late effects of the Japanese Study Group for Pediatric Liver Tumors (JPLT)-2 protocol, on the basis of cisplatin-tetrahydropyranyl-adriamycin (CITA) with risk stratification according to the pretreatment extent of disease (PRETEXT) classification for hepatoblastoma (HB). PATIENTS AND METHODS From 1999 to 201...

Background: Few clinical trials have been reported for patients with intermediate-risk neuroblastoma because of the scarcity of the disease and the variety of clinical and biological characteristics. A multidisciplinary treatment that consists of multidrug chemotherapy and surgery is expected to lead to a good prognosis with few complications. The...

Background Pulmonary hypoplasia is an important cause of morbidity and mortality in infants with congenital diaphragmatic hernia (CDH). This study aimed to verify our hypothesis that the abnormal development of bronchial cartilage as well as alveolar immaturity, might play a central role in hypoplasia of the lung in human CDH. Method We retrospect...

Biliary atresia (BA) is characterized by the inflammation and obstruction of the extrahepatic bile ducts (EHBDs) in newborn infants. SOX17 is a master regulator of the fetal EHBDs formation. In mouse Sox17+/- BA models, SOX17 reduction causes cell-autonomous epithelial shedding together with the ectopic appearance of SOX9-positive cystic duct-like...

Purpose We investigated how local tumor resection affects metastatic lesions in neuroblastoma. Methods MYCN Tg tumor-derived cells were injected subcutaneously into 129+Ter/SvJcl wild-type mice. First, the frequency of metastasis-bearing mice was investigated immunohistochemically (metastatic ratio) at endpoint or post-injection day (PID) 90. Seco...

Purpose We aimed to evaluate the effect of human mesenchymal stem cells (hMSCs) on congenital diaphragmatic hernia (CDH) by intra-amniotic injection in a rat CDH model. Methods Nitrofen (100 mg) was administered to pregnant rats at E9.5. hMSCs (1.0 × 10⁶) or PBS was injected into each amniotic cavity at E18, and fetuses were harvested at E21. The...

Emerging data have suggested that sirolimus may be a treatment option for complicated vascular anomalies (VAs). The present study aimed to investigate the immunologic effects of sirolimus treatment for 6 months in patients with VAs. Blood samples obtained from the patients enrolled in 2 multicenter studies to investigate the efficacy of sirolimus f...

Human teratoma is a germ cell tumor that contains normal tissues (e.g., hair, skin or cartilage) differentiated from embryonal germ layers. Because of the feature of this tumor, we hypothesized that human teratomas contain multipotent stem cells that can develop into various non-cancerous normal tissues. In this study, we cultured neurospheres orig...