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Tsuneya Nakamura

Publications and source records attributed to Tsuneya Nakamura.

At least 19 recordsLinked to original sources
PubMed2006

Smoking increases the treatment failure for Helicobacter pylori eradication.

PURPOSE: Treatment failure for Helicobacter pylori (H. pylori) eradication is encountered in approximately 10-20% of patients, and many studies have pointed to a link with smoking. To investigate the effects of smoking on eradication outcome, we performed a meta-analysis. METHODS: A PubMed search was performed to retrieve articles published up to August 2005. Pooled odds ratio (OR) and differences rate for H. pylori eradication failure in smokers compared with nonsmokers were used as summary statistics. Meta-regression was used for examining the source of heterogeneity. RESULTS: Twenty-two published studies (5538 patients), which provided information on eradication failure according to smoking status, were included in the analysis. The summary OR for eradication failure among smokers relative to nonsmokers was 1.95 (95% confidence interval [CI]: 1.55-2.45; P <.01). It corresponds with the differences in eradication rates between smokers and nonsmokers (8.4% [95% CI: 3.3-13.5%, P <.01]). Meta-regression analysis demonstrated that a high proportion of nonulcer dyspepsia patients in studies revealed a higher failure rate among smokers, compared with a low proportion of nonulcer dyspepsia. CONCLUSIONS: Our meta-analysis demonstrated that smoking increases the treatment failure rate for H. pylori eradication.

Anti-Bacterial Agents↗
PubMed2005

Microsatellite instability is linked to loss of hMLH1 expression in advanced gastric cancers: lack of a relationship with the histological type and phenotype.

BACKGROUND: It has been suggested that the prevalence of microsatellite instability (MSI) is high in intramucosal differentiated gastric cancers with gastric foveolar phenotypic expression, and that these tumors are prone to lose their glandular structures and progress to undifferentiated-type lesions. To test this hypothesis, we examined the relationships among human MutL homologue 1 (hMLH1) expression (which is linked to MSI), the phenotype, and the histological type in patients with advanced and intramucosal gastric cancer. METHODS: We analyzed hMLH1 expression by immunohistochemistry in 70 advanced and 30 intramucosal gastric cancers with histological evaluation and assessment of the phenotype, and Cdx2 expression determined by immunohistochemistry. The MSI status was also examined in 20 cases. RESULTS: Thirteen (18.6%) advanced and 5 (16.7%) intramucosal gastric cancers were judged to be hMLH1-negative. In the advanced cases, no association was observed between the histological type and the phenotype and loss of hMLH1. In the intramucosal cases, MUC5AC expression was observed in all 5 hMLH1-negative differentiated-type cancers. However, no hMLH1-negative lesions were detected in the intramucosal undifferentiated cancers (0/14; P < 0.05 vs differentiated types). In the advanced cases, MSI-positivity (MSI +) and loss of hMLH1 expression did correlate (P < 0.0001), while no association was observed between MSI +, histological type, and phenotype. CONCLUSION: Our data support the hypothesis that, phenotypically, some MSI-positive differentiated gastric cancers of gastric foveolar phenotypic expression may easily change, from gastric to intestinal phenotypic expression, also changing, histologically, from differentiated to undifferentiated type with progression.

Adaptor Proteins, Signal Transducing↗
PubMed2004

A pilot study of imatinib mesylate (STI571) on gastrointestinal stromal tumors in Japanese patients.

BACKGROUND: Gastrointestinal stromal tumor (GIST) is the most common type of nonepithelial tumor in the gastrointestinal tract. The gastrointestinal stromal tumor is defined immunohistologically as a c-Kit-positive tumor. For those GISTs that are malignant, the only effective treatment modality has been surgical. Early clinical reports have shown that imatinib mesylate (STI571) produces substantial anticancer activity in patients with metastatic or unresectable GIST. METHODS: Nine Japanese patients who were found clinically and immunohistochemically to have inoperable GISTs were entered into this study. These patients were given 400 mg STI571 orally once daily. We then evaluated the tumor response and the safety of the drug. RESULTS: Five of the nine patients achieved partial responses, two had stable disease, and two had progressive disease. The main side effects were skin rash, edema, periorbital edema, diarrhea, nausea, and vomiting. Mild anemia, leukocytopenia, and neutropenia were also noted. No patients required dose reduction or cessation because of adverse events. CONCLUSIONS: This study demonstrates that STI571 might be an active agent against malignant GIST in Japanese patients with manageable toxicities. Gastrointestinal stromal tumor (GIST) is the most common type of nonepithelial tumor in the gastrointestinal tract. The gastrointestinal stromal tumor is defined immunohistologically as a c-Kit-positive tumor. For those GISTs that are malignant, the only effective treatment modality has been surgical. Early clinical reports have shown that imatinib mesylate (STI571) produces substantial anticancer activity in patients with metastatic or unresectable GIST.

Adult↗
PubMed2004

Risk factors for vitamin D deficiency in patients with Crohn's disease.

BACKGROUND: Although the pathogenesis of osteopenia in Crohn's disease is not established, vitamin D deficiency is thought to be an important risk factor. However, little is known about the prevalence of vitamin D deficiency in patients with Crohn's disease in Japan. This study aimed to clarify the prevalence of vitamin D deficiency in patients with Crohn's disease in Japan and to examine the possible causes of the deficiency. METHODS: We investigated serum 25-hydroxyvitamin D (25-OHD) levels, various laboratory parameters, and patient histories in 33 outpatients (25 men, 8 women; median age, 37 years; range, 26-57 years) and 15 age- and sex-matched healthy controls (8 men, 7 women; median age, 37 years; range, 24-57 years) and assessed risk factors for vitamin D deficiency. RESULTS: Although patients with Crohn's disease did not have significantly lower serum concentrations of 25-OHD than controls, 9 of 33 patients (27.3%) were considered vitamin D deficient (serum 25-OHD level </=10 ng/ml) compared with only 1 of 15 (6.7%) controls. Serum 25-OHD levels were significantly related to disease duration ( r = 0.46, P = 0.003), Crohn's Disease Activity Index (CDAI) score ( r = 0.44, P = 0.005), International Organization for the Study of Inflammatory Bowel Disease score ( r = 0.30, P < 0.05), and serum values of ferritin ( r = 0.34, P = 0.03), C-reactive protein ( r = 0.34, P = 0.03), total cholesterol ( r = 0.31, P = 0.04), and intact parathyroid hormone ( r = 0.23, P < 0.05). A logistic regression analysis was performed to investigate the ability of variables to predict low or normal 25-OHD values. Results showed that disease duration ( P = 0.03) and CDAI score ( P = 0.04) could predict the occurrence of vitamin D deficiency ( r(2) = 0.472, P = 0.0004). CONCLUSIONS: Vitamin D deficiency exists in patients with Crohn's disease in Japan. 25-OHD levels should be assessed in patients who have had Crohn's disease for a long time (>15 years) and who have been in the active stage of the disease for long periods.

Adult↗
PubMed2004

Endoscopic ultrasound-guided fine-needle aspiration biopsy for the diagnosis of gastrointestinal stromal tumors in the stomach.

BACKGROUND: For the diagnosis of gastric submucosal tumors (SMTs), endoscopic ultrasound (EUS) alone does not reveal the complete pathology, such as the degree of malignancy, and EUS-guided fine-needle aspiration biopsy (EUS-FNAB) has been reported to be more useful. Recently, most cases initially diagnosed as leiomyosarcomas have received further study with immunohistochemical staining and have been given the new diagnosis of gastrointestinal stromal tumors (GISTs). The degree of malignancy of GISTs differs widely in clinical aspects. In this study, we examined whether EUS-FNAB was useful in diagnosing GISTs and differentiating their degrees of malignancy. METHODS: From January 1997 to March 2002, 21 cases of gastric GISTs were diagnosed from the immunohistochemical staining of specimens resected at Aichi Cancer Center Hospital. Of these 21 patients, 14 (5 with high-grade malignancy and 9 with low-grade malignancy) underwent EUS-FNAB preoperatively, and were examined further: their EUS-FNAB specimens were submitted for additional immunohistochemical testing. RESULTS: The EUS-FNAB specimens from all patients were positive for c-kit and CD34 immunohistochemical testing, coinciding with the staining results of the resected specimens. The MIB-1 labeling indices in specimens of high-grade malignancy were significantly higher than those of low-grade malignancy. If we assumed that a tumor with an MIB-1 labeling index of more than 5% was a high-grade malignancy, the diagnostic accuracy was 85.7%. CONCLUSIONS: The EUS-FNAB procedure is a useful tool for diagnosing GISTs of the stomach with immunohistochemical staining. When used with MIB-1 staining, the procedure may indicate GIST prognosis and influence decisions regarding therapeutic strategies.

Adult↗
PubMed2004

Gastric MALT lymphomas are divided into three groups based on responsiveness to Helicobacter Pylori eradication and detection of API2-MALT1 fusion.

Gastric MALT lymphoma shows unique features including regression by Helicobacter pylori eradication and API2-MALT1 fusion. We performed a molecular and clinicopathologic study for 115 cases. All eradication-responsive cases were devoid of API2-MALT1 fusion. All tumors positive for the fusion and all negative for H. pylori infection were nonresponsive to the eradication. Consequently, gastric MALT lymphomas were divided into three groups: Eradication-responsive and fusion-negative (group A, n = 72), eradication-nonresponsive and fusion-negative (group B, n = 22), and eradication-nonresponsive and fusion-positive (group C, n = 21). Group A tumors were characterized by low clinical stage and superficial gastric wall involvement, and group C tumors by low H. pylori infection rate, advanced clinical stage, and nuclear BCL10 expression. All group C tumors showed exclusively low-grade histology. Group B tumors, which have not been well recognized, frequently showed nodal involvement, deep gastric wall involvement, and advanced clinical stage, and sometimes an increased large cell component. A multivariate discriminant analysis revealed that responsiveness to the eradication could be predicted accurately by negative API2-MALT1 fusion, positive H. pylori infection, low clinical stage, and superficial gastric wall invasion, the former being the most important factor for the prediction. This 3-group categorization may be helpful for a comprehensive understanding of gastric MALT lymphoma.

Adaptor Proteins, Signal Transducing↗
PubMed2003

Endoscopic diagnosis and staging of mucinous cystic neoplasms and intraductal papillary-mucinous tumors.

BACKGROUND/PURPOSE: The number of patients with cystic neoplasms of the pancreas as detected using various types of imaging techniques has been steadily increasing. Among the cystic neoplasms, mucinous cystic neoplasms (MCNs) and intraductal papillary-mucinous tumors (IPMTs) were comparatively more frequently encountered. We used imaging techniques to focus on the differential diagnosis of MCNs and IPMTs, and tumor staging. METHODS: Fifteen patients with MCNs with ovarian-like stroma and 109 patients with IPMTs were experienced. We examined the image findings for the differential diagnosis and stage diagnosis of these two types of cystic neoplasms. RESULTS: Endoscopic ultrasonography could reveal detailed images of internal structure and was effective for the diagnosis of MCNs. Other endoscopic imaging modalities could not give specific findings for MCNs. Endoscopic retrograde cholangiopancreatography (ERCP; including duodenoscopic findings and pancreatogram) and pancreatoscopy showed the characteristic and specific findings of IPMTs. Also, endoscopic ultrasonography and intraductal ultrasonography were found to have high sensitivity and diagnostic accuracy for their differential diagnosis of neoplastic/nonneoplastic and invasive/noninvasive lesions in IPMTs. CONCLUSIONS: Endoscopic imaging techniques are capable of revealing the detailed structure of pancreatic cystic lesions. They are effective for differential diagnosis, for assessing the degree of malignancy, and for deciding upon an appropriate treatment in patients with IPMTs.

Adult↗
PubMed2003

Gastric low-grade B-cell MALT lymphoma: treatment, response, and genetic alteration.

Approximately 10% of gastric low-grade B-cell lymphomas of mucosa-associated lymphoid tissue (MALT) type are unresponsive to Helicobacter pylori ( H. pylori) eradication treatment, and many of them contain an API2-MALT1 chimeric transcript mediated by t(11;18)(q21;q21) translocation. We here review the current status on the interrelationship among clinical features, H. pylori infection status, responsiveness to antibacterial treatment, and API2-MALT1 chimeric transcript of gastric MALT lymphoma in a unicenter study experience and discuss the clinicopathologic significance of API2-MALT1 chimeric transcript in gastric MALT lymphoma. We enrolled 59 patients with gastric MALT lymphoma in a unicenter study. H. pylori infection status and clinical stages were investigated. Antibacterial treatment and subsequent follow-up endoscopy were performed for the assessment of responsiveness of MALT lymphoma in every patient. All cases were examined for API2-MALT1 chimeric transcript by means of RT-PCR and sequencing analyses using RNA extracted from tissues. H. pylori infection status was assessed as positive in 50 patients and negative in 9. Antibacterial treatment achieved complete or partial remission in 41 patients and no change in 12. API2-MALT1 chimeric transcript was detected in 9 patients, all of whom showed no change in response to treatment. Notably, responsiveness to H. pylori eradication treatment most clearly delineated the enrolled cases into two groups, indicating that six factors ( H. pylori infection, API2-MALT1 chimeric transcript, cobblestone mucosa and submucosal tumor in gross appearance, nodal involvement, and clinical stage) were statistically significant. On the other hand, comparison of two groups from the standpoint of H. pylori or API2-MALT1 chimeric transcript status revealed a lesser number of the statistically significant factors (two and three, respectively). Gastric MALT lymphoma characterized by unresponsiveness to antibacterial treatment contains all API2-MALT1 chimeric transcript-positive cases and may constitute a distinct group often seen with nodal involvement and an advanced clinical stage. This group is thought to be unrelated to H. pylori infection in its pathogenesis, and might share a unifying feature of genetic alteration such as involving the MALT1 locus on chromosome 18. Investigation in the future will clarify this issue and establish the clinical implication of such genetic alteration as the predictive factor for gastric MALT lymphoma.

Chromosome Aberrations↗
PubMed2003

A two-step method for marking polypectomy sites in the colon and rectum.

BACKGROUND: Intraoperative localization of polypectomy sites is critical for laparoscopic and open surgery, but conventional methods of marking the colorectum are sometimes unreliable. A new two-step method for marking polypectomy sites for identification during laparoscopic and open operations is described. METHODS: Eighteen patients with postpolypectomy lesions necessitating preoperative marking were enrolled in this study. A physiologic saline solution was endoscopically injected into the submucosa to produce an artificial submucosal elevation (pseudopolyp). A small volume of India ink was then injected into the submucosal elevation (pseudopolyp) with a separate needle. RESULTS: The two-step method was easily applied for all lesions without complication. At surgery, all lesions were immediately visualized. CONCLUSION: The two-step tattooing method proved to be easy, safe, and accurate for marking polypectomy sites.

Aged↗
PubMed2003

Efficacy of peroral pancreatoscopy in the diagnosis of pancreatic diseases.

BACKGROUND: The aim of this study was to evaluate the usefulness of peroral pancreatoscopy in the diagnosis of pancreatic diseases. METHODS: Both 3.7-mm (thin) and 0.8-mm (ultra-thin) diameter fiberoptic pancreatoscopes were used in 115 cases (pancreatic cancer, 35; benign ductal stenosis, 20; intraductal papillary-mucinous tumor, 60). RESULTS: Observation rates for pancreatic cancer, benign ductal stenosis, and intraductal papillary-mucinous tumor were, respectively, 63%, 80%, and 95%. Tumor vessels and papillary tumor were observed when pancreatic cancer was smaller than 2 cm but not when the tumor was larger than 2 cm. Stenosis without significant mucosal changes was observed in 62% of cases of benign ductal stenosis. Coarse mucosa and friability were observed more frequently in association with pancreatic cancer than benign ductal stenosis. Granular mucosa or papillary tumor could be observed in 74% of cases of intraductal papillary-mucinous tumor. Papillary tumor was observed with increasing frequency in cases of intraductal papillary-mucinous tumor as the degree of malignancy increased. CONCLUSIONS: Peroral pancreatoscopy with an ultra-thin fiberscope is useful in the diagnosis of minute pancreatic lesions. Peroral pancreatoscopy with a thin fiberscope can provide a definitive diagnosis of intraductal papillary-mucinous tumor including the degree of malignancy.

Adult↗
PubMed2002

No associations of p73 G4C14-to-A4T14 at exon 2 and p53 Arg72Pro polymorphisms with the risk of digestive tract cancers in Japanese.

A case-control study was conducted to examine the possible association between digestive tract cancers and p73 G4C14-to-A4T14 at exon 2 and p53 Arg72Pro polymorphisms in Japanese. Cases were 102 esophageal cancer patients, 144 stomach cancer patients, and 147 colorectal cancer patients, and controls were 241 non-cancer outpatients. The genotype frequencies among controls were 55.3% for p73 GG at position 4, 40.4% for GA, and 4.3% for AA, and 37.7% for p53 ArgArg, 44.4% for ArgPro, and 18.0% for ProPro. No significant differences in the genotype frequencies were observed between the controls and each case group or cases as a whole.

Adult↗