Hisao Tajiri

The Jikei University School of Medicine, Edo, Tōkyō, Japan

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Publications (420)1225.45 Total impact

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    ABSTRACT: Chemoimmunotherapy has been used to treat intrahepatic cholangiocarcinoma (ICC). However, little is known about the phenomena underlying the immunomodulation of ICC cells elicited by chemoimmunotherapy.
    Anticancer research 11/2014; 34(11):6353-61. · 1.71 Impact Factor
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    ABSTRACT: Abstract Introduction:Successful access to the papilla and cannulation of the desired duct can be technically challenging. A novel second-generation multi-bending backward-oblique viewing duodenoscope (2nd M-D scope) was developed to overcome this difficulty. The aim of the present study was to evaluate the utility of 2nd M-D scope during biliary ERCP. Material and methods: This was a retrospective review of 53 patients with native papilla who underwent biliary ERCP with the 2nd M-D scope. Results:Biliary cannulation and interventional procedures were successfully completed in all patients. In two of these patients, ERCP was initially attempted with a conventional single bending duodenoscope, but biliary cannulation was unsuccessful; one had Billroth-I gastrectomy, and the other had a Type III choledochal cyst. However, with the 2nd M-D scope, biliary cannulation and interventional procedures were successfully achieved. Finally, in nine patients, upward or downward angulation of the proximal bending portion in addition to the distal bending portion was used during ERCP, and the operator's comments demonstrated that it was helpful for obtaining an appropriate en face view to look up to the papilla and facilitate successful biliary cannulation. Conclusion: The newly developed 2nd M-D scope could safely facilitate biliary cannulation in selected patients during ERCP.
    Minimally Invasive Therapy & Allied Technologies. 09/2014;
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    ABSTRACT: In murine studies, cryotherapy has induced antitumor immune responses associated with the rejection of tumors. However, the effects of freezing-induced immunomodulation in breast cancer (BC) patients remain unclear.
    Anticancer research 09/2014; 34(9):4869-76. · 1.71 Impact Factor
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    ABSTRACT: The therapeutic strategy against hepatocellular carcinoma (HCC) is determined by tumor stage and liver function. Improvements of stratification contribute to extending the survival of patients. However, stratification has been attributed little attention in animal models largely due to the lack of suitable models. Herein we showed that the recently-reported, non-alcoholic steatohepatitis-derived HCC model (STAM model) is the first murine model in which the concept of human stratification is applicable by demonstrating the following features: (i) at least 4 detectable tumor nodules; (ii) average tumor growth rate of 150 % from 16 to 20 weeks of age; (iii) no visible metastasis; and (iv) relatively preserved liver function. These observations suggested that HCC in STAM mice is equivalent to stages B to C of the Barcelona Clinic Liver Cancer (BCLC) staging system for humans. Application of the stratification concept to experimental animals will create new avenues to establish pharmacological intervention against HCC.
    Anticancer research 09/2014; 34(9):4849-55. · 1.71 Impact Factor
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    ABSTRACT: We performed a phase I trial to investigate the safety, clinical responses, and Wilms' tumor 1 (WT1)-specific immune responses following treatment with dendritic cells (DC) pulsed with a mixture of three types of WT1 peptides, including both MHC class I and II-restricted epitopes, in combination with chemotherapy.
    Clinical cancer research : an official journal of the American Association for Cancer Research. 07/2014;
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    ABSTRACT: To evaluate significant risk factors for incomplete colonoscopy at a Japanese academic hospital.
    World journal of gastroenterology : WJG. 06/2014; 20(22):6961-7.
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    ABSTRACT: Objectives: C-reactive protein (CRP) is a practical prognostic marker in patients with hepatocellular carcinoma (HCC). We investigated the prognostic value of adding the CRP level to other validated staging systems (Cancer Liver Italian Program, Japan Integrated Staging, Barcelona Clinic Liver Cancer classification system, Tokyo score and tumor node metastasis classification) in HCC patients. Methods: One hundred and eighty-six newly diagnosed HCC patients were retrospectively evaluated. A multivariate analysis identified the clinicopathological variables associated with overall survival; the variables identified were then added to each staging system and compared to those without the additional variable. Results: In multivariate analysis, an elevated serum CRP level was independently associated with a poor prognosis (hazard ratio 3.792, p < 0.0001). The addition of the CRP level to each of the established staging systems provided a higher linear χ(2) value and a lower -2 log likelihood than those without the addition of the term. Moreover, the area under the receiver-operating characteristic curve (AUC) analysis showed that the addition of CRP improved the AUC of each staging system. Conclusions: This study demonstrates that an elevated serum CRP level is independently associated with a poor prognosis in HCC patients, and the addition of the CRP level to the validated staging systems could improve the prognostic ability of each staging system. © 2014 S. Karger AG, Basel.
    Oncology 06/2014; 86(5-6):308-317. · 2.17 Impact Factor
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    ABSTRACT: C-reactive protein (CRP) is used as a biomarker of ulcerative colitis (UC) activity, but CRP levels are sometimes insufficient to reflect UC activity. Therefore, a simple noninvasive biomarker assay with sufficient sensitivity and specificity to accurately reflect UC activity is desired. Since prostaglandin E2 production and colonic inflammation are associated, we evaluated whether prostaglandin E-major urinary metabolite (PGE-MUM) can be used as such a biomarker.
    Inflammatory Bowel Diseases 05/2014; · 5.12 Impact Factor
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    ABSTRACT: Previous work has demonstrated that fusion cells generated from autologous monocyte-derived dendritic cells (MoDCs) and whole tumor cells induce efficient antigen-specific cytotoxic T lymphocytes. A major limitation to the use of this strategy is the availability of adequate amounts of autologous tumor cells. Moreover, MoDCs from cancer patients are often defective in their antigen-processing and presentation machinery. In this study, two types of allogeneic cells, a leukemia plasmacytoid dendritic cell (pDC) line (PMDC05) and pancreatic cancer cell lines (PANC-1 or MIA PaCa-2), were fused instead of autologous MoDCs and tumor cells. We created four types of pDC/tumor fusion cells by alternating fusion partners and treating with lipopolysaccharide (LPS): i) PMDC05 fused with PANC-1 (pDC/PANC-1), ii) PMDC05 fused with MIA PaCa-2 (pDC/MIA PaCa-2), iii) LPS-stimulated pDC/PANC-1 (LPS-pDC/PANC-1) and iv) LPS-stimulated pDC/MIA PaCa-2 (LPS-pDC/MIA PaCa-2) and examined their antitumor immune responses. The LPS-pDC/tumor cell fusions were the most active, as demonstrated by their: i) upregulated expression of HLA-DR and CD86 on a per-fusion-cell basis, ii) increased production of IL-12p70, iii) generation of a higher percentage of IFN-γ-producing CD4+ and CD8+ T cells and iv) augmented induction of MUC1-specific CD8+ T cells that lyse target tumor cells. This study provides the first evidence for an in vitro induction of antigen-specific cytotoxic T lymphocytes by LPS-stimulated fusion cells generated from leukemia plasmacytoid DCs and tumor cells and suggests that this strategy has potential applicability to the field of adoptive immunotherapy.
    International Journal of Oncology 05/2014; · 2.66 Impact Factor
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    Kenichi Goda, Tomohiro Kato, Hisao Tajiri
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    ABSTRACT: Barrett's esophagus (BE) is a metaplastic condition that occurs secondary to gastroesophageal reflux disease. BE is also a precursor to esophageal adenocarcinoma, which, although still rare in Japan, is one of the most rapidly increasing cancers in Western countries. However, the prevalence of gastroesophageal reflux disease has increased significantly over the past few decades in Japan, possibly leading to an incremental rise in BE and the associated inherent risk of adenocarcinoma. Given the poor prognosis of advanced-stage Barrett's adenocarcinoma, endoscopic surveillance is recommended for subjects with BE to detect early neoplasias including dysplasia. However, endoscopic identification of dysplastic lesions is still not sufficiently reliable or subjective, making targeted therapy extremely difficult. Over the past few years, improvements in image resolution, image processing software, and optical filter technology have enabled identification of dysplasia and early cancer in BE patients. We retrieved as many studies on advanced endoscopic technologies in BE as possible from MEDLINE and PubMed. The present review focuses on the emergent clinically available technologies to provide an overview of the technologies, their practical applicability, current status, and future challenges.
    Digestive Endoscopy 05/2014; 26(3). · 1.61 Impact Factor
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    ABSTRACT: Background and AimThe impact of frequent colonoscopy on colorectal cancer (CRC) remains unclear. The present study aimed to determine the relationship between frequency of surveillance colonoscopy and CRC prevention.Methods From April 2010 to April 2011, patients who underwent surveillance colonoscopy after screening and polypectomy in four Japanese endoscopy centers were enrolled in this multicenter historical cohort study. Patients were classified into the following two groups according to the findings of past colonoscopy: a low-risk group (no neoplasia or 1–2 cumulative adenomas <10 mm) and an increased-risk group (advanced adenoma or ≥3 cumulative adenomas). The relationship between colonoscopy frequency within the previous 5 years and the prevalence of advanced neoplasia in each group was analyzed using multiple logistic regression.ResultsThe final analysis included 2391 patients. In the low-risk group, the odds ratios for advanced adenoma in patientsundergoing moderately frequent colonoscopy (2–3 times within the previous 5 years), and frequent colonoscopy (≥4 times within 5 years) were 0.33 (95% confidence interval [CI], 0.14–0.81) and 0.21 (95% CI, 0.02–1.60), respectively, compared with infrequent colonoscopy (once or not at all within 5 years). In the increased-risk group, the respective odds ratios were 0.48 (95% CI, 0.28–0.83) and 0.28 (95% CI, 0.12–0.64).Conclusions Although frequent colonoscopy provides benefits against advanced adenoma, the optimal benefit was achieved at 2–3 times. With very frequent colonoscopy (i.e. ≥4 times within 5 years), the additional risk reduction for advanced adenoma was relatively small.
    Digestive Endoscopy 05/2014; 26(3). · 1.61 Impact Factor
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    ABSTRACT: Endoscopic retrograde cholangiopancreatography (ERCP) has played a major role in the diagnosis of biliary and pancreatic diseases. The prevalence and mortality rate of post-ERCP pancreatitis (PEP) remains a serious issue that needs to be resolved. Here, we report the first ERCP study that was conducted at a high-volume center of an educational institution in Japan. This study investigated patients with suspected biliary and pancreatic diseases who had undergone ERCP between April 2006 and June 2009. We created a database and analyzed preoperative and postoperative data. Patients who had undergone surgery and those with a history of undergoing duodenal papilla treatment were excluded. Mild (n=62) or moderate (n=3) pancreatitis was present in 65 cases (6.21%; 36 men and 29 women). A univariate analysis identified age under 50 years (P=0.01), pancreatography (P<0.001), and biliary stent placement (P<0.001). A Multivariate analysis was performed for evaluating the risk factors associated with PEP. This analysis identified age of the patients under 50 years [P=0.003; odds ratio (OR), 0.37; 95% confidence interval (CI), 0.19-0.71], endoscopic papillary balloon dilation (P=0.012; OR, 4.69; 95% CI, 1.41-15.54), pancreatography (P<0.001; OR, 5.55; 95% CI, 2.98-10.33), and plastic stent placement (P<0.001; OR, 3.77; 95% CI, 2.17-6.54). Descriptive statistics showed that only pancreatography was associated with PEP. An additional sphincterotomy did not increase the risk of PEP (P=0.306; OR, 2.03; 95% CI, 0.52-7.84), and even adjusted for pancreatography. We changed the size of the stent to 7-Fr. In the future, we plan to repeat the same study with a higher number of cases.
    Surgical laparoscopy, endoscopy & percutaneous techniques 04/2014; · 0.88 Impact Factor
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    ABSTRACT: Advanced complex surgery performed with the natural orifice translumenal endoscopic surgery technique requires use of a multitasking platform. The aim of this study is to evaluate the basic functionality of a prototype multitasking platform "EndoSAMURAI" with the use of a biosimulation model and ex vivo porcine stomach. We compared the performance of basic surgical skill tasks between the EndoSAMURAI and standard laparoscopic instrumentation. Basic surgical tasks include cutting, dissection, and suturing and knot tying. Main outcome measurements were the time to complete each task and leak pressure to evaluate the quality of the suturing and knot tying. Although it took longer to perform all basic surgical tasks with the EndoSAMURAI than with laparoscopic instrumentation, all tasks could be performed precisely and with an accuracy comparable to that of the laparoscopic technique. Leak pressures of the gastric closure site between both techniques were also comparable.
    Surgical laparoscopy, endoscopy & percutaneous techniques 04/2014; · 0.88 Impact Factor
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    ABSTRACT: Submucosal endoscopy with a mucosal flap (SEMF) safety valve technique is a global concept in which the submucosa is a free working space for endoscopic interventions. A purposefully created intramural space provides an endoscopic access route to the deeper layers and into the extraluminal cavities. The mucosa overlying the intramural space is protective, reducing contamination during natural orifice transluminal endoscopic surgery (NOTES) procedures and providing a sealant flap to repair the entry point and the submucosal space. In addition to NOTES, SEMF enables endoscopic achalasia myotomy, histologic analysis of the muscularis propria, and submucosal tumor removal.
    Gastrointestinal endoscopy clinics of North America 04/2014; 24(2):265-272.
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    ABSTRACT: Background and AimWe previously reported the effectiveness of color tone intensity analysis using autofluorescence imaging (AFI) for distinguishing between colorectal neoplastic and non-neoplastic lesions. Moreover, a second-generation AFI system has become commercially available in Japan. In the present study, we assessed the effectiveness of color tone intensity analysis using a second-generation AFI system for evaluating diminutive colorectal lesions.Methods We retrospectively reviewed the cases of 35 consecutive patients with 101 diminutive colorectal lesions that were examined using a second-generation AFI system and resected at the Jikei University Hospital. We estimated the mean green-to-red (G/R) ratio – obtained by dividing the green color tone intensity by the red color tone intensity – of the lesions and compared the values of the neoplastic and non-neoplastic lesions. We also assessed the sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of the AFI system for neoplastic lesion identification.ResultsThe mean G/R ratios of the non-neoplastic and neoplastic lesions were 1.06 and 0.87, respectively; the mean G/R ratio significantly differed between the neoplastic and non-neoplastic lesions. Using the second-generation AFI system, neoplastic lesions were identified with a sensitivity, specificity, PPV, and NPV of 94.2%, 91.8%, 92.5%, and 93.8%, respectively.Conclusion Color intensity analysis of diminutive colorectal polyps using the second generation AFI system could effectively distinguish between neoplastic and non-neoplastic lesions.
    Digestive Endoscopy 04/2014; 26(S2). · 1.61 Impact Factor
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    ABSTRACT: Differentiation of gallbladder (GB) carcinoma from benign GB wall thickening is challenging. The recent introduction of second-generation ultrasonic contrast agents has made contrast harmonic imaging with EUS possible. The aim of our study was to evaluate the utility of contrast-enhanced harmonic EUS (CH-EUS) for the differential diagnosis of GB wall thickening. Thirty-six consecutive patients with GB wall thickening imaged by CH-EUS and then underwent surgery were enrolled in this study. After the lesions were observed with conventional harmonic EUS (H-EUS), CH-EUS was performed with intravenous injection of 0.015 ml/kg of Sonazoid. Three reviewers with various levels of experience of EUS (Reviewer A: experienced endosonographer, B: EUS trainee, C: experienced gastroenterologist with expertise in transabdominal ultrasound but no EUS experience) were blinded to findings of recorded video of H-EUS and CH-EUS. The diagnostic accuracy of H-EUS and CH-EUS for malignant GB wall thickening was compared. Final diagnoses based on surgical histology were GB carcinoma in 16, cholecystitis in 11, adenomyomatosis in 6 and cholesterolosis in 3. Overall sensitivity, specificity and accuracy for diagnosing malignant GB wall thickening of H-EUS and CH-EUS were 83.3 versus 89.6, 65 versus 98 % (p < 0.001) and 73.1 versus 94.4 % (p < 0.001). The inter-observer agreement for H-EUS was moderate (κ = 0.51), whereas that for CH-EUS was substantial (κ = 0.77). The inhomogeneous enhanced pattern on CH-EUS was a strong predictive factor of malignant GB wall thickening. CH-EUS has the potential to improve the preoperative diagnostic accuracy and inter-observer agreement in the differential diagnosis of GB wall thickening.
    Digestive Diseases and Sciences 03/2014; · 2.26 Impact Factor
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    ABSTRACT: Upper gastrointestinal endoscopy is mostly performed under sedation and has a low yield of relevant gastric lesions in patients without alarm symptoms. Simpler screening tests such as capsule endoscopy could be helpful, but gastric visualization is insufficient with the current passive capsules. A magnetically guided gastric capsule was prospectively evaluated in patients with routine indications for gastroscopy. A total of 189 symptomatic patients (105 male; mean age 53 y) from 2 French centers subsequently and blindly underwent capsule and conventional gastroscopy by 9 and 6 examiners, respectively. The final gold standard was unblinded conventional gastroscopy with biopsy under propofol sedation. Main outcome was accuracy (sensitivity/specificity) of capsule gastroscopy for diagnosis of major gastric lesions, defined as those lesions requiring conventional gastroscopy for biopsy or removal. Twenty-three major lesions were found in 21 patients. Capsule accuracy was 90.5% [95% confidence interval (CI), 85.4%-94.3%] with a specificity of 94.1% (95% CI, 89.3%-97.1%) and a sensitivity of 61.9% (95% CI, 38%-82%). Accuracy did not correlate with lesion location, gastric luminal visibility, examiner case volume, or examination time. Of the remaining 168 patients, 94% had minor and mostly multiple lesions; the capsule made a correct diagnosis in 88.1% (95% CI, 82.2%-92.6%), with gastric visibility and lesion location in the proximal stomach having significant influence. All patients preferred capsule gastroscopy. In a prospective and strictly blinded study, magnetically guided capsule gastroscopy was shown to be feasible in clinical practice and was clearly preferred by patients. Improvements in capsule technology may render this technique a future alternative to gastroscopy.
    Journal of clinical gastroenterology 03/2014; · 2.21 Impact Factor
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    ABSTRACT: Background We previously demonstrated that antibiotic combination therapy is effective for induction and maintenance of ulcerative colitis (UC) remission.AimTo assess whether antibiotic combination therapy is effective for active UC refractory to or dependent on steroids in a multicentre, open-label trial.Methods We enrolled 30 patients with steroid-refractory and 64 with steroid-dependent active UC. These patients received three-times-daily by mouth amoxicillin 500 mg, tetracycline 500 mg and metronidazole 250 mg, for two weeks, as well as conventional treatment. Symptom assessment and colonoscopic evaluation were performed before enrolment and at 3 and 12 months after treatment completion. Clinical response was defined as a Lichtiger symptom score decrease in ≥3 points and clinical remission as a score ≤4.ResultsNineteen of the 30 steroid-refractory (63.3%) and 47 of the 64 steroid-dependent (73.4%) patients showed a clinical response within 2 weeks. At 3 and 12 months, 60% and 66.6% of steroid-refractory patients, and 56.3% and 51.6% of steroid-dependent patients, respectively, achieved clinical remission. In the steroid-dependent group, 39 of the 64 patients (60.9%) were able to stop steroid therapy and remained in remission for 3 months. Three (10%) steroid-refractory and four (6.3%) steroid-dependent patients underwent colectomy.Conclusions This multicentre, long-term follow-up study suggests 2 week antibiotic combination therapy to be effective and safe in patients with active UC refractory to or dependent on steroids.
    Alimentary Pharmacology & Therapeutics 03/2014; · 4.55 Impact Factor
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    ABSTRACT: Wilms tumor gene (WT1) protein is an attractive target for cancer immunotherapy. We aimed to investigate the feasibility of a combination therapy consisting of gemcitabine and WT1 peptide-based vaccine for patients with advanced pancreatic cancer and to make initial assessments of its clinical efficacy and immunologic response. Thirty-two HLA-A*24:02 patients with advanced pancreatic cancer were enrolled. Patients received HLA-A*24:02-restricted, modified 9-mer WT1 peptide (3 mg/body) emulsified with Montanide ISA51 adjuvant (WT1 vaccine) intradermally biweekly and gemcitabine (1000 mg/m) on days 1, 8, and 15 of a 28-day cycle. This combination therapy was well tolerated. The frequencies of grade 3-4 adverse events for this combination therapy were similar to those for gemcitabine alone. Objective response rate was 20.0% (6/30 evaluable patients). Median survival time and 1-year survival rate were 8.1 months and 29%, respectively. The association between longer survival and positive delayed-type hypersensitivity to WT1 peptide was statistically significant, and longer survivors featured a higher frequency of memory-phenotype WT1-specific cytotoxic T lymphocytes both before and after treatment. WT1 vaccine in combination with gemcitabine was well tolerated for patients with advanced pancreatic cancer. Delayed-type hypersensitivity-positivity to WT1 peptide and a higher frequency of memory-phenotype WT1-specific cytotoxic T lymphocytes could be useful prognostic markers for survival in the combination therapy with gemcitabine and WT1 vaccine. Further clinical investigation is warranted to determine the effectiveness of this combination therapy.
    Journal of immunotherapy (Hagerstown, Md.: 1997) 02/2014; · 3.20 Impact Factor
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    ABSTRACT: To investigate dysfunctions in esophageal peristalsis and sensation in patients with Barrett's esophagus following acid infusion using endoscopy-based testing. First, physiological saline was infused into the esophagus of five healthy subjects, at a rate of 10 mL/min for 10 min, followed by infusion of HCl. Esophageal contractions were analyzed to determine whether the contractions observed by endoscopy and ultrasonography corresponded to the esophageal peristaltic waves diagnosed by manometry. Next, using nasal endoscopy, esophageal sensations and contractions were investigated in patients with, as well as controls without, Barrett's esophagus using the same infusion protocol. All except one of the propulsive contractions identified endoscopically were recorded as secondary peristaltic waves by manometry. Patients with long segment Barrett's esophagus (LSBE) tended to have a shorter lag time than the control group, although the difference did not reach statistical significance (88 ± 54 s vs 162 ± 150 s respectively, P = 0.14). Furthermore, patients with LSBE had significantly fewer secondary contractions following the infusion of both saline and HCl than did either the control group or patients with short segment Barrett's esophagus (4.1 ± 1.2 vs 8.0 ± 2.8, P < 0.001 and 7.3 ± 3.2, P < 0.01, respectively, following saline infusion; 5.3 ± 1.2 vs 8.4 ± 2.4 and 8.1 ± 2.9 respectively, P < 0.01 for both, following infusion of HCl). Using nasal endoscopy and a simple acid-perfusion study, we were able to demonstrate disorders in secondary peristalsis in patients with LSBE.
    World Journal of Gastroenterology 01/2014; 20(3):822-8. · 2.55 Impact Factor

Publication Stats

4k Citations
1,225.45 Total Impact Points


  • 2003–2014
    • The Jikei University School of Medicine
      • • Division of Gastroenterology and Hepatology
      • • Department of Internal Medicine
      • • Department of Endoscopy
      • • Department of Surgery
      Edo, Tōkyō, Japan
    • University of Milan
      Milano, Lombardy, Italy
  • 2013
    • The Chinese University of Hong Kong
      • Department of Surgery
      Hong Kong, Hong Kong
  • 2011–2013
    • The University of Tokyo
      • • Department of Endoscopy and Endoscopic Surgery
      • • Faculty & Graduate School of Medicine
      Tokyo, Tokyo-to, Japan
  • 2012
    • Japanese Foundation for Cancer Research
      Edo, Tōkyō, Japan
  • 1989–2012
    • National Cancer Center
      • • Endoscopy Division
      • • Department of Diagnostic Radiology
      Tokyo, Tokyo-to, Japan
  • 2010–2011
    • Toranomon Hospital
      Edo, Tōkyō, Japan
    • Kyoto University
      • Department of Gastroenterology and Hepatology
      Kyoto, Kyoto-fu, Japan
    • Kashiwa City Hospital
      Kashiwa, Chiba, Japan
  • 2009–2011
    • Institut Arnault Tzanck
      • Department of Hepato-Gastroenterology
      Saint-Laurent, Provence-Alpes-Côte d'Azur, France
  • 2008
    • Jichi Medical University
      • Division of Gastroenterology
      Totigi, Tochigi, Japan
  • 1999–2007
    • Chiba-East National Hospital
      Tiba, Chiba, Japan
  • 2004
    • San Giuseppe Hospital
      Ареццо, Tuscany, Italy
    • National Defense Medical College
      • Division of Environmental Medicine
      Tokorozawa, Saitama-ken, Japan
  • 2000–2004
    • Shikoku Cancer Center
      Matuyama, Ehime, Japan
  • 1991
    • National Hospital Organization Kyushu Cancer Center
      Hukuoka, Fukuoka, Japan