Hideki Niwa

Kanazawa Medical University, Kanazawa, Ishikawa, Japan

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Publications (12)37.59 Total impact

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    ABSTRACT: BACKGROUND: Narrow-band imaging (NBI) is useful for detecting superficial oropharyngeal lesions. However, the diagnostic and treatment guidelines for NBI are not established. The aim of the present study was to evaluate the treatment strategy for these microlesions. METHODS: From October 2008 to September 2009, 68 flat-type brownish microlesions were observed in the orohypopharynx using NBI. Lesions were examined via magnifying NBI (M-NBI) and followed up without biopsy or endoscopic resection for >12 months. To clarify the characteristics, lesions were compared with the endoscopic characteristics of flat-type lesions diagnosed by biopsy and endoscopic resection as squamous cell carcinoma and high-grade intraepithelial neoplasia. RESULTS: The average diameter of the 68 lesions was 1.6 mm (range, 0.5-5 mm). At the 1-year follow up, 19 lesions had disappeared. No size increases or morphological changes wereobserved among 49 lesions followed for >1 year. At 2 years, 10 patients had dropped out and 11 lesions had disappeared. No changes were observed among 28 lesions followed for >2 years. Of the flat-type lesions as squamous cell carcinoma and high-grade intraepithelial neoplasia, a distinct border and irregular distribution of atypical vessels were observed in all cases using M-NBI. These findings were observed in two of 68 flat-type brownish microlesions during follow up. CONCLUSION: Although there is some possibility of squamous cell carcinoma or high-grade intraepithelial neoplasia, flat-type microlesions of ≤5 mm diameter in the orohypopharynx may be followed for up to 2 years without biopsy or endoscopic resection.
    Digestive Endoscopy 06/2013; · 1.61 Impact Factor
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    ABSTRACT: Patients with bone metastasis originating from gastric cancer experience complications from DIC. They are treated with anticoagulation therapy or platelet transfusion, but their prognosis is poor. Our case was a 50-year-old male who had undergone distal gastrectomy for early gastric cancer[pT1a(M)N0M0, pStage I a]ten years previously. He was admitted to our hospital complaining of backache. As a result of his examination, he was diagnosed with disseminated carcinosis of bone marrow with DIC as a postoperative recurrence of gastric cancer. The patient was treated with combination chemotherapy of S-1 and cisplatin(S-1 80 mg/body, po, day 1-21 and cisplatin 50mg/body, iv, day 8). After one course of treatment, DIC was resolved and his pain was relieved. He survived for about nine months. S-1 and cisplatin are considered to be effective for disseminated carcinosis of bone marrow.
    Gan to kagaku ryoho. Cancer & chemotherapy 05/2012; 39(5):813-5.
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    ABSTRACT: Cancer stem cells reportedly participate in the tumorigenesis of some neoplasms. Scirrhous hepatocellular carcinoma is a variant of hepatocellular carcinoma with abundant fibrous stroma. Herein, we clinicopathologically examined scirrhous (29 cases) and conventional (50 cases) hepatocellular carcinoma with reference to cancer stem cells. Scirrhous hepatocellular carcinoma was classifiable into 3 types based on small neoplastic cells at the periphery of tumor cell nests. Of 29 cases of scirrhous hepatocellular carcinoma, 21 contained small neoplastic cells. Immunohistochemically, those cells were positive for cytokeratin 7 and ATP-binding cassette transporter G2. In 11 cases, those small tumor cells were also positive for cytokeratin 19, neural cell adhesion molecule, and epithelial cell adhesion molecule (type 1), whereas 10 cases did not show such additional expression (type 2). The remaining 8 tumors did not contain small tumor cells with stem cell features (type 3). In the central parts of tumor nests, carcinoma cells got hepatocellular markers and lost expression of neural cell adhesion molecule, and epithelial cell adhesion molecule, suggesting hepatocellular maturation. Transforming growth factor beta1, a fibrogenic cytokine, was also detected in those small tumor cells. Culture cells extracted as "side population" from hepatocellular carcinoma cell lines (HuH7 and PLC5) expressed more intensely cytokeratins 7 and 19, neural cell adhesion molecule, epithelial cell adhesion molecule, and transforming growth factor beta1 than did non-side population cells. Small tumor cells with stem cell features in scirrhous hepatocellular carcinoma may correspond to side population of culture cells and might be involved in fibrogenesis of scirrhous hepatocellular carcinoma.
    Human pathology 07/2008; 39(8):1185-96. · 3.03 Impact Factor
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    ABSTRACT: Aim: Serum antinuclear antibodies (ANA) are occasionally noted in patients with non-alcoholic steatohepatitis (NASH). We examined the significance of ANA in NASH. Methods: We compared clinicopathological features in patients with ANA-positive NASH (n = 35) and ANA-negative NASH (n = 36). Inflammatory cell profiles and the distribution of oxidative stress markers were also examined immunohistochemically. Results: ANA-positive NASH was significantly associated with female gender (P = 0.005), high degree of portal inflammation (P = 0.039), interface activity (P = 0.036) and hepatocellular ballooning (P = 0.0008). In addition, ANA of high titer (320-fold or more) was significantly associated with the histological grade and stage of NASH (P = 0.02). The degree of steatosis wais rather mild in the high-titer ANA group(P = 0.01). The analysis of inflammatory cell profiles revealed that CD3-positive T cells were predominant and plasma cells were rather few in the portal area and hepatic lobules in both ANA-positive and ANA-negative groups. There was no difference in the distribution of oxidative stress markers between ANA-positive and ANA-negative groups. Conclusion: These findings suggest that the presence of ANA may be related to the progression of NASH and that a different type of autoimmune mechanism may be involved in the pathogenesis of NASH with ANA, compared to the pathogenesis of autoimmune hepatitis.
    Hepatology Research 12/2007; 37(11):923-31. · 2.07 Impact Factor
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    ABSTRACT: Recently, attention has been drawn to papillary neoplasm of the pancreatobiliary systems. In the pancreas, the disease entity of intraductal papillary mucinous neoplasm (IPMN-P) is widely recognized. In contrast, the pathological characteristics of biliary papillary tumors, such as biliary papilloma(tosis) and papillary cholangiocarcinoma, have not yet been well documented. In this study, we compared the pathological features and post-operative prognosis among biliary papillary tumors (10 cases of biliary papilloma(tosis) and 22 cases of papillary cholangiocarcinoma), conventional non-papillary cholangiocarcinoma (15 cases), and IPMN-P (31 cases). Macroscopically, all biliary papillary tumors were characterized by the prominent intraductal papillary proliferation, and macroscopic mucin-hypersecretion was seen in 9 of 32 cases (28%). Histologically, biliary papillary tumors consisted of three types of tumor cells (pancreaticobiliary, intestinal and gastric types), whereas only the pancreaticobiliary type was observed in non-papillary cholangiocarcinoma. Immunohistochemically, biliary papillary tumors were characterized by the common expression of MUC2, CDX2 and cytokeratin 20. In addition, biliary papillary tumors could be associated with two types of invasive lesions: tubular adenocarcinoma (9 cases) and mucinous carcinoma (5 cases). Patients with tubular adenocarcinoma had a poor prognosis compared to non-invasive papillary tumor or papillary tumor with mucinous carcinoma. These pathological characteristics and the survival status of biliary papillary tumors were different from those of non-papillary cholangiocarcinoma, and rather closely resembled those of IPMN-P. In conclusion, biliary papillary tumors may be the biliary counterpart (intraductal papillary neoplasm of the bile duct) of IPMN-P.
    Hepatology 12/2006; 44(5):1333-43. · 12.00 Impact Factor
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    ABSTRACT: Gastric carcinoma is still a major leading cause of cancer death in East Asia. Since angiogenesis is a necessary condition for invasion and metastasis, its regulation is of essential significance. Expressions of MMP-2, MMP-9 and VEGF were examined with microarray of gastric carcinoma tissue samples (n = 249) by immunostaining. In addition, microvessel density (MVD) was assessed after labelling with the anti-CD34 antibody. Data were cross-compared with clinicopathological parameters of tumors, including PTEN expression. Expressions of MMP-2, MMP-9 and VEGF were positively correlated with tumour size, depth of invasion, lymphatic and venous invasion, lymph node metastasis, UICC staging and MVD of gastric carcinomas (p < 0.05).VEGF expression was positively linked with levels of MMP-2 and MMP-9 (p < 0.05), but negatively with PTEN (p < 0.05). The latter was also inversely associated with the MVD in gastric carcinomas (p < 0.05). MMP-2, MMP-9 and VEGF largely contribute to the angiogenesis and progression of gastric carcinomas. PTEN might inhibit the processes by down-regulating VEGF expression. These parameters should be regarded as good markers to indicate pathobiological behaviours of gastric carcinomas.
    Anticancer research 01/2006; 26(5A):3579-83. · 1.71 Impact Factor
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    ABSTRACT: The association between IgG4 dysregulation and inflammatory pseudotumor (IPT) was first reported in sclerosing pancreatitis. Recently, we described IPTs of the liver and breast, into both of which many IgG4-positive plasma cells had infiltrated. In this study, we examined the clinical and histological features of 9 cases of IPT (histologically corresponding to plasma cell granuloma) of the lung with an emphasis on IgG4-positive plasma cell infiltration. The lesions were characterized histologically by dense lymphoplasmacytic infiltrates intermixed with fibrosis and, in some cases, prominent eosinophilic infiltration, irregular narrowing of bronchioles entrapped in nodules, and an interstitial pneumonia pattern at the boundaries of nodules. Obliterative phlebitis was easily found in all cases, and 5 lesions also had obliterative arteritis. Immunostaining revealed many IgG4-positive plasma cells diffusely distributed within nodules, and the ratios of IgG4-positive to other plasma cells were extraordinarily high. Of the 9 patients, 8 underwent surgical treatment and in 1 patient, lesion was diagnosed on transbronchial biopsy and effectively treated with corticosteroid. Two cases were associated with chronic sclerosing sialadenitis or lymphadenopathy, in which many IgG4-positive plasma cells were also identified by immunostaining. The clinicopathologic similarities between IPT of the lung and sclerosing pancreatitis suggest that IgG4-related immunopathologic processes might be involved in the pathogenesis of the pulmonary lesions.
    Human Pathlogy 08/2005; 36(7):710-7. · 2.84 Impact Factor
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    ABSTRACT: Chronic sclerosing sialadenitis (CSS) is a cryptogenic tumor-like condition of the salivary gland(s). While immune-mediated processes are suspected in its pathogenesis, and CSS is occasionally reported to be associated with sclerosing pancreatitis, an IgG4-related disease, the exact immunopathologic processes of CSS remain speculative. In this study, we examined the clinicopathologic findings of CSS (12 cases) in comparison with sialolithiasis (8 cases) and Sjogren's syndrome (13 cases), and tried to clarify whether CSS is an IgG4-related disease or not. Submandibular gland(s) were affected in all cases of CSS. CSS cases could be divided into two types: 5 cases were associated with sclerosing lesions in extrasalivary glandular tissue (systemic type), while only salivary gland(s) were affected in the remaining 7 cases (localized type). In the former type, which showed male predominance, bilateral salivary glands were frequently affected, and eosinophilia and elevations of gamma-globulin and IgG in serum were frequently found. Histologically, all cases of CSS showed marked lymphoplasmacytic infiltration admixed with fibrosis and the destruction of glandular lobules. Obliterative phlebitis was found in the affected salivary glands in all cases of CSS. Immunohistochemically, the proportion of IgG4/IgG-positive plasma cells was more than 45% in CSS, while it was less than 5% in controls. The resemblance of the clinicopathologic features of CSS with those of sclerosing pancreatitis suggests the participation of a similar immunopathologic process with IgG4 disturbance in CSS. The abundance of IgG4-positive plasma cells in the lesions would be useful for distinguishing CSS from other forms of sialadenitis.
    American Journal of Surgical Pathology 07/2005; 29(6):783-91. · 4.87 Impact Factor
  • American Journal of Surgical Pathology - AMER J SURG PATHOL. 01/2005; 29(6):783-791.
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    ABSTRACT: Sclerosing cholangitis (SC) is a heterogeneous disease entity. Different etiologies such as choledocholithiasis, biliary tumor, or pericholangitis can manifest as SC. Hepatic inflammatory pseudotumor (IP) is rarely associated with SC (sclerosing cholangitis associated with hepatic inflammatory pseudotumor; SC-hepatic IP), but sclerosing pancreatitis (SP) is not infrequently associated with bile duct lesions (sclerosing pancreatitis-associated sclerosing cholangitis; SP-SC). In this study, we compared the histologic changes of hepatic hilar and extrahepatic bile duct lesions of SC (7 cases), SC-hepatic IP (5 cases), SP-SC (5 cases), and typical primary sclerosing cholangitis (PSC) (5 cases). Histologically, all SP-SC cases showed extensive and dense fibrosis with marked lymphoplasmacytic infiltration, many eosinophils, and obliterative phlebitis. Four cases of SC showed bile duct lesions similar to those of SP-SC, whereas other three cases of SC showed milder lymphoplasmacytic infiltration, scant eosinophilic cell infiltration, and no obliterative phlebitis. All SC-hepatic IP cases showed bile duct lesions identical to those of SP-SC. Immunohistochemically, many IgG4-positive plasma cells were found in the bile duct lesions of all SP-SC cases, 4 SC cases with marked lymphoplasmacytic infiltration, and all SC-hepatic IP cases. By contrast, IgG4-positive plasma cells were scarce or hardly found in the remaining 3 SC cases and all PSC cases. In conclusion, 4 SC cases and all SC-hepatic IP cases showed bile duct lesions identical to those of SP-SC, suggesting that these three conditions may be a single disease entity. Their pathogenesis may be similar or closely related to that of SP, and in that respect they may represent an IgG4-related biliary disease. They may respond to steroid therapy as SP does.
    American Journal of Surgical Pathology 10/2004; 28(9):1193-203. · 4.87 Impact Factor
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    ABSTRACT: A rare case of primary pulmonary synovial sarcoma with polypoid endobronchial growth in a 42-year-old Japanese woman is described. Left upper sleeve lobectomy was performed for the polypoid tumor measuring 2.5 cm in the left major bronchus and the patient was treated with adjuvant chemotherapy. Three years later, a recurrent tumor was discovered. Microscopically, this tumor was characterized by a proliferation of oval to spindle-shaped cells arranged in sheets and fascicles and covered by the thin normal bronchial epithelium. Immunohistochemically, tumor cells were positive for vimentin, and focally positive for pancytokeratin recognized by AE1/AE3, cytokeratin 7 and epithelial membrane antigen. A chimera gene, SYT-SSX1, was detected. Recently, primary pulmonary synovial sarcoma is an increasingly recognized clinical entity; however, most of these tumors present as a parenchymal mass. The present case is a unique example of primary synovial sarcoma of endobronchial polypoid type. This case suggests that pulmonary synovial sarcoma might originate from bronchial submucosal stromal tissue.
    Pathology International 09/2004; 54(8):611-5. · 1.72 Impact Factor
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    ABSTRACT: To examine the pathological changes of hepatic arteries in idiopathic portal hypertension (IPH) which is characterized by the obliteration of the intrahepatic portal vein branches and presinusoidal portal hypertension. Liver specimens (biopsied or surgically resected) from 20 patients with IPH, 20 patients with alcoholic fibrosis/cirrhosis (AF/C) and 20 histologically normal livers were used. The vascular lumina of arterial and venous vessels in portal tracts were morphometrically evaluated by an image analysis system. The ratio of portal venous luminal area to portal tract area (portal venous index) of IPH and that of AF/C were significantly reduced compared with normal liver. The portal venous index for IPH was significantly lower than that for AF/C. The ratio of hepatic arterial luminal area to portal tract area for AF/C was significantly higher than that in normal liver; however, that for IPH was similar to normal. The peribiliary vascular plexus was increased in AF/C but not in IPH. In AF/C, the number of mast cells and macrophages known to be the source of angiogenic substances was significantly increased in the portal tract compared with normal liver, while in IPH it was not increased. In AF/C, a reduction in portal venous lumen was associated with an increase of hepatic arterial lumen and of angiogenesis-related cells in portal tracts. However, such compensatory arterial changes were not evident in IPH, and this compensatory failure may be a feature of IPH.
    Histopathology 08/2003; 43(1):55-61. · 2.86 Impact Factor