Publications by authors named "Ryuichiro Doi"

Article Synopsis
  • * The updated Clinical Practice Guidelines for Gastroenteropancreatic Neuroendocrine Neoplasms (GEP-NENs) cover essential topics like diagnosis, treatment options, and associated genetic conditions, including MEN1 and VHL diseases.
  • * These guidelines highlight new diagnostic criteria and treatment options, such as health insurance coverage for certain therapies, improving the management of NEN through the incorporation of recent evidence and clinical insights.
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Article Synopsis
  • - Experts discussed and determined the best treatment strategies for unresectable pancreatic neuroendocrine tumors (PanNETs) based on previous studies.
  • - Key indicators like liver metastases volume and Ki-67 labeling index were identified to decide on treatment options: somatostatin analogues for smaller, slower-growing tumors, cytotoxic agents for larger, faster-growing ones, and molecular-targeted agents for intermediate cases.
  • - A tentative treatment MAP (management action plan) was created and showed promise for guiding treatment, but more extensive studies are needed to confirm its effectiveness.
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Introduction: Gastrointestinal (GI) involvement in hepatocellular carcinoma (HCC) is uncommon. In particular, HCC with duodenal invasion is known to be a rare condition. In such cases, surgical indication has been generally negative except in few reported cases.

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Gastrointestinal Burkitt lymphoma (BL) is a highly aggressive malignancy in childhood, and early treatment is critical for its favorable prognosis. Ultrasonography is a widely accepted initial imaging workup; therefore, recognition of the sonographic features of BL should contribute to its early diagnosis and initiation of treatment. We present a 4-year-old boy with primary jejunal BL with intussusception mimicking presentation, in which initial abdominal US allowed sustainable detection and characterization of the intestinal lesion.

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Purposes: In the surgical treatment of pancreatic cancer, margin-negative status is one of the most important determinants of survival. We conducted this study to explore surgical margin status as well as other factors affecting the survival of borderline-resectable pancreatic cancer (BRPC) patients who received neoadjuvant chemotherapy with gemcitabine and S-1.

Methods: Eighteen BRPC patients were prospectively treated with concurrent gemcitabine and S-1 neoadjuvant chemotherapy (NAC+) and 15 of these patients underwent resection.

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A 40-year-old man admitted to our hospital with diarrhea underwent abdominal computed tomography (CT) which showed multiple masses in the liver and pancreatic tail. Although there were no abnormal accumulations with fluorodeoxyglucose ((18)F) positron emission tomography (FDG-PET), (68)Ga-DOTATOC-PET/CT detected obvious abnormal accumulations for the both lobes of liver and pancreatic tail tumors. The serum gastrin was markedly high, and liver tumor biopsy demonstrated the presence of malignant cells with round nuclei that were positive for gastrin and somatostatin receptor.

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Pancreatic neuroendocrine tumors (pNETs) include functioning and non-functional tumors. Functioning tumors consist of tumors that produce a variety of hormones and their clinical effects. Therefore, determinants of resection of pNETs should be discussed for each group of tumors.

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The molecular mechanisms underlying the development of pancreatic neuroendocrine tumors (PanNETs) have not been well defined. We report here that the genomic region of the PHLDA3 gene undergoes loss of heterozygosity (LOH) at a remarkably high frequency in human PanNETs, and this genetic change is correlated with disease progression and poor prognosis. We also show that the PHLDA3 locus undergoes methylation in addition to LOH, suggesting that a two-hit inactivation of the PHLDA3 gene is required for PanNET development.

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Objective: This study aimed to elucidate the natural history of intraductal papillary mucinous neoplasm (IPMN) of the pancreas with mural nodules (MNs) in branch duct IPMN (BD-IPMN).

Methods: Among the 402 registered patients with BD-IPMN on long-term follow-up at 10 institutions in Japan, 53 patients with MNs of less than 10 mm in height detected by endosonography were included in this study. The morphological changes of the BD-IPMN in these patients and histologic findings of the resected specimen were investigated.

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Objective: GPR119 is reportedly involved in regulating glucose metabolism and food intake in rodents, but little is known about its expression and functional significance in humans. To begin to assess the potential clinical importance of GPR119, the distribution of GPR119 gene expression in humans was examined.

Materials/methods: Expression of GPR119 mRNA in fresh samples of normal human pancreas (n=19) and pancreatic islets (n=3) and in insulinomas (n=2) and glucagonomas (n=2), all collected at surgery, was compared with the mRNA expression of various receptors highly expressed and operative in human pancreatic islets.

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A 78-year-old man who had hepatitis C was examined by computed tomography(CT)because of prostate cancer, and was found to have a liver tumor 8. 0 cm in size at S4/S8. The view of the liver tumor was enhanced by CTHA image and washed out by CTAP image.

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A 49-year-old man was admitted to the hospital for the upper abdominal pain and was diagnosed as unresectable pancreatic head cancer because of the invasion around the superior mesenteric artery. He was treated with radiochemotherapy, followed by systemic gemcitabine alone for 3 courses. He was further treated with systemic gemcitabine plus S‑1 combination therapy for 5 courses.

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Transplantation of surrogate β-cells is a promising option for the treatment of insulin-deficient diabetes mellitus in the future. Although pancreatic exocrine cells of rodents have been shown to transdifferentiate into insulin-secreting cells, no studies are reported on human exocrine cells. Here, we report the generation of insulin-secreting cells from exocrine cells of the human pancreas.

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Extrahepatic bile duct cancer with an endocrine cell component has rarely been reported. We report here on a case of adenoendocrine cell carcinoma in the middle bile duct. An 82-year-old man was admitted to hospital for jaundice and anorexia.

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Objective: We aimed to elucidate the accuracy and limitations of [(18)F]-fluoro-L-dihydroxyphenylalanine ([(18) F]DOPA) positron emission tomography (PET) for Japanese patients with congenital hyperinsulinism. Although [(18)F]DOPA PET is reported to be useful for precisely localizing the focal form of congenital hyperinsulinism, previous reports are mostly from European and North American centres.

Patients: Seventeen Japanese infants with congenital hyperinsulinism.

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Background/purpose: It is important to predict the development of clinically relevant pancreatic fistula (grade B/C) in the early period after pancreaticoduodenectomy (PD). This study has been carried out as a project study of the Japanese Society of Hepato-Biliary-Pancreatic Surgery (JSHPBS) to evaluate the predictive factors associated with clinically relevant pancreatic fistula (grade B/C).

Method: The data of 1,239 patients from 11 medical institutions who had undergone PD between July 2005 and June 2009 were retrospectively analyzed to review patient characteristics and perioperative and postoperative parameters.

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Aim: To search for the optimal surgery for gastrinoma and duodenopancreatic neuroendocrine tumors in patients with multiple endocrine neoplasia type 1.

Methods: Sixteen patients with genetically confirmed multiple endocrine neoplasia type 1 (MEN 1) and Zollinger-Ellison syndrome (ZES) underwent resection of both gastrinomas and duodenopancreatic neuroendocrine tumors (NETs) between 1991 and 2009. For localization of gastrinoma, selective arterial secretagogue injection test (SASI test) with secretin or calcium solution was performed as well as somatostatin receptor scintigraphy (SRS) and other imaging methods such as computed tomography (CT) or magnetic resonance imaging (MRI).

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