Masahiro Ito

NHO Nagasaki Medical Center, Nagasaki, Nagasaki, Japan

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Publications (148)382.84 Total impact

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    ABSTRACT: Background & aimsThe aim of the present study is to evaluate the factors influencing biochemical response to treatment and the value of biochemical response for predicting long-term outcomes in Japanese patients with PBC.Patients and Methods Biochemical response to ursodeoxycholic acid (UDCA) or UDCA plus bezafibrate was defined as good (≤ULN), fair (≤1.5 x ULN), or poor (>1.5 x ULN) at 2 years after initiation of UDCA treatment. Associations between various factors (including age, sex, autoantibody status, and histological variables at baseline), biochemical response to treatment, and long-term outcomes were evaluated in 164 Japanese PBC patients.ResultsAnti-gp210 positivity and a higher bile duct loss score were significant risk factors for worse ALP response (OR, 2.78 and 1.85, respectively). Age, anti-gp210 positivity, and anti-centromere positivity were significant risk factors for worse ALT response (OR, 1.05, 4.0, and 2.77, respectively). Anti-gp210 positivity and a higher hepatitis score were significant risk factors for worse IgM response (OR, 2.10 and 2.06, respectively). Worse ALP and IgM response were significant risk factors for progression to late-stage disease without jaundice (OR, 2.27 and 2.32, respectively). Worse ALT response was a significant risk factor for progression to late-stage disease with persistent jaundice (OR, 11.11).Conclusions Biochemical response to treatment at 2 years, which is influenced by autoantibody status and histological variables at baseline, can predict long-term outcomes in Japanese patients with PBC.
    Hepatology Research 09/2014; · 2.07 Impact Factor
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    ABSTRACT: Background: The BRAFV600E mutation is the most common genetic alteration in papillary thyroid carcinomas (PTCs). Transgenic mice overexpressing BRAFV600E in their thyroids under control of the thyroglobulin promoter (Tg-BRAF2 mice) developed invasive PTCs with high penetrance; however, these mice showed elevated TSH levels, which also stimulate proliferation of thyrocytes and tumorigenesis. The purpose of the present study was to investigate how TSH signaling cooperates with BRAFV600E in the process of thyroid carcinogenesis. Methods: We crossed Tg-BRAF2 mice with TSH receptor knockout (TshR-/-) mice. Four genetically distinct mice groups, Brafwt; TshR+/- (group 1), Brafwt; TshR-/- (group 2), Tg-BRAF2; TshR+/- (group 3), and Tg-BRAF2; TshR-/- (group 4), were sacrificed at 12 and 24 weeks of age. We performed histopathological analysis. Genomic instability was also evaluated by immunofluorescence for p53-binding protein 1 (53BP1) and γH2AX. Invasiveness and genomic instability were also evaluated using thyroid PCCL3 cells. Results: Groups 3 and 4 developed distinct neoplasia comparable to human PTCs. Group 3 developed typically larger, more aggressive, invasive tumors compared to group 4. The frequency of 53BP1 and γH2AX foci, indicators of genomic instability, in group 3 was higher than that in group 4. TSH signal also enhanced invasiveness and genomic instability in PCCL3 cells with BRAFV600E expression. Conclusion: These data demonstrate that the TSH signaling confers more aggressive features on BRAFV600E-induced thyroid tumors in mice. This might be due in part to accelerated genomic instability.
    Thyroid: official journal of the American Thyroid Association 08/2013; · 2.60 Impact Factor
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    ABSTRACT: Through a genome-wide association study of a Japanese population, we recently identified TNFSF15, a gene encoding TNF-like ligand 1A (TL1A), as a susceptibility gene for primary biliary cirrhosis (PBC). We investigated the clinical significance of TL1A and one of its receptors, decoy receptor 3 (DcR3), in PBC. We analysed the systemic and local expression of TL1A and DcR3 in 110 PBC patients and 46 healthy controls using enzyme-linked immunosorbent assay, quantitative polymerase chain reaction and immunohistochemical staining. Serum TL1A levels were significantly increased in PBC patients at both early and late stages as compared with healthy controls, and its levels were significantly decreased in early-stage PBC patients after ursodeoxycholic acid (UDCA) treatment. TL1A was immunohistochemically localized to biliary epithelial cells, Kupffer cells, blood vessels and infiltrating mononuclear cells in the PBC liver. In addition, TL1A messenger RNA expression was increased in the PBC liver as compared with the non-diseased liver. Serum DcR3 levels were also significantly increased in PBC patients, and were significantly decreased after UDCA treatment in early-stage PBC patients. These results indicate that TL1A and DcR3 may play an important role in the pathogenesis of PBC.
    Liver international: official journal of the International Association for the Study of the Liver 08/2013; · 3.87 Impact Factor
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    ABSTRACT: In a previous report, we proposed that analysis of 53BP1 expression by immunofluorescence could be a useful tool in estimating the level of genomic instability (GIN), as well as the malignant potential, of thyroid tumours. In an attempt to clarify the value of 53BP1 expression as a new molecular marker for the aggressiveness of thyroid papillary microcarcinoma (PMC), we assessed the association between the type of 53BP1 expression and clinicopathological features such as tumour size, extrathyroidal invasion, lymph node metastasis and BRAF(V) (600E) mutation of PMC. A total of 36 surgically resected thyroid tumours, including 13 PMC and 23 conventional papillary thyroid carcinomas (PTC), were available for this study. Analysis using immunofluorescence revealed that the incidence of an abnormal or high DNA damage response (DDR) type of 53BP1 expression was significantly higher in PTC than PMC. BRAF(V) (600E) mutation was not associated significantly with tumour aggressiveness in either PMC or PTC cases. Abnormal/high DDR type of 53BP1 expression was associated closely with both BRAF(V) (600E) mutation and papillary and/or trabecular architecture of PMC. Abnormal/high DDR type of 53BP1 expression might be associated with GIN and papillary/trabecular morphology at an early stage of PTC carcinogenesis through BRAF(V) (600E) mutation.
    Histopathology 07/2013; · 2.86 Impact Factor
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    ABSTRACT: Background: Neuroendocrine tumor (NET) of the thyroid other than medullary carcinoma is extremely rare. We describe here a case of calcitonin-negative small cell neuroendocrine carcinoma (SCNEC), which occurred in the thyroid gland that had previously been irradiated at high dose (60Gy) for pharyngeal cancer, with molecular analyses for follicular cell origin. Patient Findings: The tumor cells were small in size with fine chromatin, inconspicuous nucleoli, and inapparent cytoplasm, and showed neuroendocrine architectures, such as palisading, rosettes, and trabeculae. Mitotic figures were numerous exceeding 10 mitoses per 10 high power fields. The tumor cells invaded into several vessels and metastasized to regional lymph nodes. Immunohistochemically, the tumor cells were strongly positive for neuroendocrine markers and thyroglobulin (Tg), a marker of thyroid follicular cells, but negative for calcitonin and carcinoembryonic antigen (CEA). Expression of Tg and thyrotropin receptor (TSHR) were confirmed by quantitative real-time RT-PCR. Ki-67 labeling index was more than 70% in the tumor cells. Taken together, the tumor was diagnosed as SCNEC of the thyroid. Genetic analyses also revealed microsatellite abnormalities of the phosphatase and tensin homolog (PTEN) gene, suggesting that functional loss of PTEN contributes to carcinogenesis. Conclusions: This is the first report describing a SCNEC of the thyroid with molecular analyses that provide evidence for a follicular epithelial origin.
    Thyroid: official journal of the American Thyroid Association 07/2013; · 2.60 Impact Factor
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    ABSTRACT: To explore mutations in serine/threonine kinase 11 (STK11) gene in Peutz-Jeghers syndrome (PJS) with gastrointestinal (GI) hamartomatous polyps. Six Japanese PJS patients in 3 families were enrolled in this study. Each of the cases had hamartomatous polyposis in the gastrointestinal tract, including the small intestine, along with mucocutaneous hyperpigmentation. Narrow-band imaging (NBI)-magnification endoscopy was employed to detect microvascular and microsurface irregularities in the GI lesions. NBI magnification findings could be classified into three groups (type A, type B, or type C). Endoscopic polypectomy was performed using double-balloon enteroscopy or colonoscopy. Genomic DNA was extracted from a whole blood sample from each subject. All of the coding exons of STK11 gene, its boundary regions, and the promoter region containing the polymorphic regions were amplified by polymerase chain reaction, and direct sequencing was performed to assess the germline mutations. NBI-magnification endoscopic observation could detect the abnormalities in microvessels and microsurface structures of GI polyps. Overall, we found 5 cases of type A and one case without the examination for the gastric polyps, while there were 4 cases of type B and 2 case of type A for the colorectal polyps. Seventy-nine small-bowel and 115 colorectal polyps over 27 sessions for each were resected endoscopically without significant complications. The only delayed complication included the occurrence of bleeding in a case, and this was successfully managed with hemoclips. Resected polyps contained no malignant components. Based on mutation analysis, all 3 cases in Family I exhibited the +658C>T nonsense mutation in exon 5, which resulted in the production of a truncated protein (Q220X). In Family II, a case had -252C>A and -193C>A in the promoter region. In Family III, a case was found to have the +1062C>G (F342L) mutation in exon 8. We found two novel mutations of STK11 in association with PJS. Endoscopic polypectomy of GI polyps in PJS patients appears to be useful to prevent emergency laparotomies and reduce the cancer risk.
    World journal of gastrointestinal endoscopy. 03/2013; 5(3):102-10.
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    ABSTRACT: Malignant rhabdoid tumor is a rare tumor occurring mostly in the neonatal kidneys and central nervous system. Cutaneous malignant rhabdoid tumors are extremely rare in adults. The aim of the study was to report on the clinical, histologic, and immunophenotypic characteristics of this cutaneous malignant rhabdoid tumor which developed in an adult. A 27-yearold male complained of a right palm neoplasm that had been present for 6 months, which was initially diagnosed as an epithelioid sarcoma by biopsy. However, detailed investigation with immunohistochemistry enabled us to make a diagnosis of a rhabdoid tumor. The patient underwent radical abrasion, chemotherapy, and rradiation, and has survived for 1 year without relapse. Only 20 adult cases have been reported thus far in the English literature. We are reporting the 21st case, who remains disease-free at 12 months. Complete resection and local irradiation may increase survival, because there is no standard and reliable curative chemotherapeutic regimen.
    Rare tumors 01/2013; 5:e36.
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    ABSTRACT: Malignant rhabdoid tumor is a rare tumor occurring mostly in the neonatal kidneys and central nervous system. Cutaneous malignant rhabdoid tumors are extremely rare in adults. The aim of the study was to report on the clinical, histologic, and immunophenotypic characteristics of this cutaneous malignant rhabdoid tumor which developed in an adult. A 27-year-old male complained of a right palm neoplasm that had been present for 6 months, which was initially diagnosed as an epithelioid sarcoma by biopsy. However, detailed investigation with immunohistochemistry enabled us to make a diagnosis of a rhabdoid tumor. The patient underwent radical abrasion, chemotherapy, and irradiation, and has survived for 1 year without relapse. Only 20 adult cases have been reported thus far in the English literature. We are reporting the 21(st) case, who remains disease-free at 12 months. Complete resection and local irradiation may increase survival, because there is no standard and reliable curative chemotherapeutic regimen.
    Rare tumors 01/2013; 5(3):e36.
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    ABSTRACT: Background: Hepatitis B e antigen (HBeAg) seroconversion is an important hallmark in the natural course of chronic hepatitis B. This study was designed to predict early HBeAg seroconversion within 1 year, by not only biochemical and virological markers, but also pathological parameters in patients with chronic hepatitis B. Material/Methods: In a retrospective cohort study, 234 patients with HBeAg were reviewed for demographic, biochemical, virological and pathological data at the time of liver biopsy. Then, the patients who accomplished HBeAg seroconversion within 1 year thereafter were compared with those who did not, for sorting out factors predictive of early HBeAg seroconversion. Results: Early HBeAg seroconversion occurred in 58 (24.8%) patients. In univariate analysis, factors predictive of early HBeAg seroconversion were: alanine aminotransferase (ALT) (p=0.002), IP-10 (p=0.029), HBsAg (p=0.003), HBeAg (p<0.001), HBV DNA (p=0.001), HBcrAg (p=0.001), core-promoter mutations (p=0.040), fibrosis (p=0.033) and lobular inflammation (p=0.002). In multivariate analysis, only serum HBeAg levels <100 Paul Ehrlich Institute (PEI) U/ml and grades of lobular inflammation ≥2 were independent factors for early HBeAg seroconversion (odds ratio 8.430 [95% confidence interval 4.173-17.032], p<0.001; and 4.330 [2.009-9.331], p<0.001; respectively). Conclusions: HBeAg levels < 100 PEIU/ml combined with grades of lobular inflammation ≥2 are useful for predicting early HBeAg seroconversion. In patients without liver biopsies, high ALT levels (≥200 IU/L) can substitute for lobular inflammation (grades ≥2).
    Medical science monitor: international medical journal of experimental and clinical research 12/2012; 18(12):CR698-705. · 1.22 Impact Factor
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    ABSTRACT: We describe herein a patient who presented with immunoglobulin G4-related disease (IgG4-RD) involving the testis and prostate as well as the submandibular glands. Massive infiltration of IgG4-expressing plasma cells was observed in testis and prostate tissues. Serum concentrations of B cell activating factor belonging to the tumor necrosis factor family (BAFF) were elevated in parallel with serum IgG4 concentrations, and infiltration of BAFF-receptor (BAFF-R)-expressing B cells and BAFF-expressing lymphoid cells was observed around the ectopic lymphoid foci in the affected urogenital tissues. To date, testicular involvement in a patient diagnosed with IgG4-RD had not been reported, making this the first reported case of IgG4-related epididymo-orchitis. These findings suggest that the immune mechanism underlying ectopic lymphoneogenesis in IgG4-RD may involve enhanced BAFF/BAFF-R interactions among lymphoid cells.
    Modern Rheumatology 09/2012; · 1.72 Impact Factor
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    ABSTRACT: To establish an animal model with human hepatocyte-repopulated liver for the study of liver cancer metastasis. Cell transplantation into mouse livers was conducted using alpha-fetoprotein (AFP)-producing human gastric cancer cells (h-GCCs) and h-hepatocytes as donor cells in a transgenic mouse line expressing urokinase-type plasminogen activator (uPA) driven by the albumin enhancer/promoter crossed with a severe combined immunodeficient (SCID) mouse line (uPA/SCID mice). Host mice were divided into two groups (A and B). Group A mice were transplanted with h-GCCs alone, and group B mice were transplanted with h-GCCs and h-hepatocytes together. The replacement index (RI), which is the ratio of transplanted h-GCCs and h-hepatocytes that occupy the examined area of a histological section, was estimated by measuring h-AFP and h-albumin concentrations in sera, respectively, as well as by immunohistochemical analyses of h-AFP and human cytokeratin 18 in histological sections. The h-GCCs successfully engrafted, repopulated, and colonized the livers of mice in group A (RI = 22.0% ± 2.6%). These mice had moderately differentiated adenocarcinomatous lesions with disrupted glandular structures, which is a characteristics feature of gastric cancers. The serum h-AFP level reached 211.0 ± 142.2 g/mL (range, 7.1-324.2 g/mL). In group B mice, the h-GCCs and h-hepatocytes independently engrafted, repopulated the host liver, and developed colonies (RI = 12.0% ± 6.8% and 66.0% ± 12.3%, respectively). h-GCC colonies also showed typical adenocarcinomatous glandular structures around the h-hepatocyte-colonies. These mice survived for the full 56 day-study and did not exhibit any metastasis of h-GCCs in the extrahepatic regions during the observational period. The mice with an h-hepatocyte-repopulated liver possessed metastasized h-GCCs and therefore could be a useful humanized liver animal model for studying liver cancer metastasis in vivo. A novel animal model of human liver cancer metastasis was established using the uPA/SCID mouse line. This model could be useful for in vivo testing of anti-cancer drugs and for studying the mechanisms of human liver cancer metastasis.
    World Journal of Gastroenterology 08/2012; 18(29):3875-82. · 2.55 Impact Factor
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    ABSTRACT: Patients with rheumatoid arthritis (RA), especially those treated with methotrexate (MTX), might have an increased risk of lymphoproliferative disorders that are associated with Epstein-Barr virus (EBV). We describe a case of EBV-associated central nervous system (CNS) lymphoma (diffuse large B-cell lymphoma) in a patient with RA on a short course of MTX treatment. The neoplastic cells express the B-cell surface markers (CD20, Pax-5 and CD30), and EBV-encoded RNA was demonstrated by in situ hybridization. The patient's lymphoma did not recur for the 8-year follow-up period after the tumor resection and cessation of MTX. MTX may promote EBV-positive CNS lymphoma in RA patient due to its immunosuppressive properties as well as reactivating latent EBV infection.
    Modern Rheumatology 07/2012; · 1.72 Impact Factor
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    ABSTRACT: A 61-year-old woman presented with dementia, 7 years after an operation for retroperitoneal leiomyosarcoma. Magnetic resonance imaging (MRI) revealed enhanced masses with perifocal edema in the bilateral frontal regions and a very small mass in the right medial frontal region. The tumors in the bilateral frontal regions were completely removed surgically, and γ-knife radiotherapy was administered for the very small tumor in the right medial frontal region. The histological diagnosis was metastatic leiomyosarcoma. Postoperatively, an MRI showed that the perifocal edemahad decreased, and the symptoms gradually improved. Cerebral metastasis from a retroperitoneal leiomyosarcoma is very uncommon. Ideally, the tumors should be surgically removed because radiotherapy and chemotherapy are apparently ineffective. A combination of complete surgical removal and γ-knife radiotherapy may be effective in prolonging patient survival.
    Brain and nerve = Shinkei kenkyū no shinpo 05/2012; 64(5):565-9.
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    ABSTRACT: The recognition and visualization of an arterial gas embolism are difficult. We report a case of sudden death caused by paradoxical air embolism of coronary and cerebral arteries, diagnosed by the pre autopsy computed tomography (CT) scanning. A 54-year-old woman suddenly died after the self-removal of the jugular vein catheter. Postmortem imaging examination using CT scanning showed multiple gas embolisms in the cerebral arteries, pulmonary artery, right atrium and ventricle, left ventricle, aorta, and coronary arteries. These findings suggested that the occurrence of acute ischemia of the brain and heart caused by massive air inflow to the artery. Conventional autopsy revealed a patent foramen ovale of the heart. These results indicated that the patient died of paradoxical air embolization of the coronary and cerebral arteries through a patent foramen ovale because of right-to-left shunting. The use of postmortem imaging as an aid for conventional autopsy has proved to be of advantage in the case of gas embolism.
    Journal of Forensic Sciences 02/2012; 57(4):1118-9. · 1.24 Impact Factor
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    ABSTRACT: Chronic hepatobiliary inflammatory diseases are not widely acknowledged as underlying disorders of systemic AA amyloidosis, except epidemic schistosomiasis. Among them, primary sclerosing cholangitis (PSC) might initiate amyloid A protein deposition in diverse tissues, giving rise to systemic amyloidosis, due to a progressive and unresolved inflammatory process, and its possible association with inflammatory bowel diseases. Nevertheless, only one such case has been reported in the literature to date. We report a 69-year-old Japanese woman with cirrhosis who was diagnosed with PSC complicated with systemic AA amyloidosis, without any evidence of other inflammatory disorders. As a result of cholestasis in conjunction with biliary strictures and increased serum IgG4, the presence of IgG4(+) plasma cells was examined systemically, resulting in unexpected documentation of Congo-red-positive amyloid deposits, but not IgG4(+) plasma cells, in the liver, stomach and salivary glands. Elevated serum IgG4 is the hallmark of IgG4-related disease, including IgG4-associated cholangitis, but it has also been demonstrated in certain patients with PSC. Amyloid A deposits in multiple organs associated with an indolent clinical course that progresses over many years might have a diagnostic value in discriminating PSC from IgG4-associated cholangitis.
    World Journal of Gastroenterology 01/2012; 18(2):192-6. · 2.55 Impact Factor
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    ABSTRACT: Polyarteritis nodosa (PAN) is a rare, systemic necrotizing vasculitis of small and medium size arteries that leads to aneurysms in various organs. Aneurysms associated with PAN are common in visceral arteries, however, intracranial aneurysms are rare, especially in childhood. A pediatric patient with PAN developed serial hemorrhagic strokes from a ruptured superior cerebellar artery aneurysm (subarachnoid hemorrhage) and a de novo aneurysm of the frontoorbital artery (intracerebral hemorrhage) after 9 months. Patients with PAN who present with intracranial aneurysms are candidates for intervention even if the aneurysm is unruptured and still small, and close observation is needed to detect de novo aneurysms in patients with chronic history of PAN.
    Neurologia medico-chirurgica 01/2012; 52(12):928-32. · 0.49 Impact Factor
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    ABSTRACT: Although the outcome of autoimmune hepatitis (AIH) is generally good, the natural course and likelihood of progression to cirrhosis or hepatocellular carcinoma (HCC) remain undefined, and may vary by region and population structure. Our aims were to evaluate risk factors that contribute to poor outcome and particularly development of HCC in a prospective multicentric cohort study of AIH. The study group comprised 193 Japanese patients with AIH who were prospectively followed up at annual intervals between 1995 and 2008. The mean follow-up period was 8.0 ± 4.5 years. Twenty-one (10.9%) patients had cirrhosis at presentation and a further 15 (7.8%) developed cirrhosis during the follow-up period. Survival rates were 94.2% at 10 years and 89.3% at 15 years. HCC was diagnosed in seven of the 193 patients. The presence of cirrhosis at presentation was a risk factor for HCC according to a Cox proportional hazard model, and the HCC-free survival rate was significantly lower in those with cirrhosis compared to those without cirrhosis according to Kaplan-Meier analysis. Although the outcome of AIH is as good if not better among Japanese than for other populations, there was an increased risk of HCC in these patients. Cirrhosis at presentation was predictive of development of HCC in AIH in Japan.
    Liver international: official journal of the International Association for the Study of the Liver 12/2011; 32(5):837-44. · 3.87 Impact Factor
  • Pathology International 11/2011; 61(11):694-6. · 1.72 Impact Factor
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    ABSTRACT: IgG4-related sclerosing disease (IgG4-RSD) is an inflammatory and fibrosing disorder characterized by lymphoplasmacytic inflammation with infiltration of various organs, including the pancreas, bile ducts, lung, kidney, and retroperitoneum. As for malignancy in IgG4-RSD, only limited literature is available. We report here a case of thyroid papillary carcinoma showing unique morphology in IgG4-RSD. Solid tumor nests were surrounded by dense IgG4-positive plasma cells and fibrosis at both the primary site and metastatic lymph nodes. In contrast the background thyroid showed focal lymphocytic thyroiditis. IgG4-related sclerosing sialadenitis and autoimmune pancreatitis were also diagnosed, and prednisolone treatment improved symptoms and serum IgG4 abnormality. To the best of our knowledge, this is the first documentation of a malignancy of the thyroid gland occurring in a background of IgG4-RSD. A brief review of the literature on the relationship between IgG4 and malignancy is included.
    Pathology International 10/2011; 61(10):589-92. · 1.72 Impact Factor
  • Neuropathology 05/2011; 31(5):556-9. · 1.91 Impact Factor

Publication Stats

1k Citations
382.84 Total Impact Points


  • 2002–2014
    • NHO Nagasaki Medical Center
      Nagasaki, Nagasaki, Japan
  • 2000–2013
    • Nagasaki University
      • • Atomic Bomb Disease Institute
      • • Graduate School of Biomedical Sciences
      Nagasaki-shi, Nagasaki-ken, Japan
  • 1996–2013
    • Nagasaki University Hospital
      Nagasaki, Nagasaki, Japan
  • 2011
    • Kurume University
      • Department of Pathology
      Куруме, Fukuoka, Japan
  • 2002–2011
    • Hokuriku Central Hospital
      Nanto-shi, Toyama, Japan