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Tatsuyuki Kawano

Publications and source records attributed to Tatsuyuki Kawano.

11 recordsLinked to original sources
PubMed2006

Esophageal carcinoma: evaluation with high-resolution three-dimensional constructive interference in steady state MR imaging in vitro.

PURPOSE: To determine the usefulness of high-resolution three-dimensional (3D) constructive interference in steady state (CISS) MRI for evaluating mural invasion and morphologic features in esophageal carcinomas. MATERIALS AND METHODS: Twenty-four esophageal specimens with carcinomas were studied with a 1.5-T system using a 4-cm-diameter loop coil. High-resolution 3D-CISS MR images were obtained with a field of view (FOV) of 80 mm, matrix of 256 x 256, and section thickness of 0.5 mm (voxel size of 0.05 mm(3)). 3D-CISS MR images were compared with histopathologic findings, and virtual MR endoscopic images were compared with macroscopic findings at surgery. RESULTS: 3D-CISS MR images clearly depicted the normal esophageal wall as consisting of eight layers, which correlated well with the histologic layers. In 22 of 24 esophageal carcinomas (92%), the depth of mural invasion visualized with 3D-CISS MRI correlated well with the histopathologic staging. In all 24 carcinomas (100%), virtual MR endoscopic images clearly depicted the macroscopic types of the carcinomas, including adjacent lymph node swelling. CONCLUSION: High-resolution 3D-CISS MRI has a high diagnostic accuracy for evaluating mural invasion and macroscopic findings in esophageal carcinomas, and may be applicable to preoperative histopathologic staging and morphologic evaluation.

Aged↗
PubMed2006

Accelerated growth of intestinal tumours after radiation exposure in Mlh1-knockout mice: evaluation of the late effect of radiation on a mouse model of HNPCC.

Mlh1-knockout mice have been developed as a useful model of hereditary non-polyposis colorectal cancer (HNPCC). In this study, we analyzed the pathology of gastrointestinal tumours (GIT) in these mice in detail and examined the possible effects of ionizing radiation on the induction of intestinal tumours to evaluate the late response to radiotherapy in HNPCC. Mlh1-/- mice spontaneously developed GIT and thymic lymphomas by 48 weeks. GIT included not only well differentiated adenocarcinomas but also poorly differentiated and mucinous adenocarcinomas, suggesting that this mouse is a good model for HNPCC. In contrast to colon cancers from HNPCC patients, however, carcinomas of Mlh1-/- mice expressed p53 and showed a lack of transforming growth factor (TGF)-betaRII mutation, which resulted in the expression of TGF-betaRII protein. Irradiation of 10-week-old Mlh1-/- mice accelerated GIT development but had little effect at 2 weeks. Mlh1+/- and Mlh1+/+ mice were not susceptible to spontaneous or radiation-induced thymic lymphomas and GIT until 72 weeks after birth. The development and pathology of GIT in Mlh1-/- mice suggest that this mouse is a good model for HNPCC, although tumour-related responsible genes might be different from HNPCC. As X-ray exposure promoted carcinogenesis of GIT in adult Mlh1-/- mice, an increased risk of secondary cancers after radiotherapy for HNPCC patients should be taken into consideration.

Adaptor Proteins, Signal Transducing↗
PubMed2005

Laparoscopy-assisted resection of gastric remnant cancer.

We report a case of gastric remnant carcinoma (GRC) that was successfully treated by laparoscopy-assisted gastrectomy. A 69-year-old man was referred to our department for management of GRC. Preoperative investigations revealed a slightly elevated tumor, 5.0 cm in maximal diameter, confined to the gastric mucosa. Computed tomography and endoscopic ultrasonography identified no lymph node metastasis. Laparoscopy-assisted gastrectomy was performed including perigastric and mesenteric lymph node dissection. The postoperative course was uneventful. This is the first reported case of laparoscopically treated GRC. In cases with little adhesion from previous surgery, laparoscopic procedure might represent the treatment of choice for early GRC in terms of minimal invasiveness.

Aged↗
PubMed2005

[Progression and extending speed of Barrett's esophagus].

Barrett's esophagus is one of the terminal manifestations of reflux esophagitis. Although the typical Barrett's esophagus is very rare in Japan, the prevalence rate of short-segment Barrett's esophagus is extremely higher comparing with in western countries. The discrepancy may be caused by the differences of criteria of short-segment Barrett's esophagus. Observation of Barrett's mucosa in residual esophagus after esophagectomy is a useful method of considering the extension of Barrett's esophagus. Short-segment Barrett's esophagus accompanied by gastro-esophageal reflux may show a rapid extension under some adequate conditions. Large volume prospective studies are needed to clarify the extension speed of Barrett's esophagus.

Barrett Esophagus↗
PubMed2005

[Nationwide epidemiological survey regarding heartburn and reflux esophagitis in Japanese].

The details on prevalence of heartburn and reflux esophagitis have not been clarified, since no large-scale survey has been conducted to date. Accordingly, we conducted the nationwide survey regarding prevalence of heartburn and reflux esophagitis by asking new outpatients and patients with the first endoscopy to be performed who visited the medical institutions participating in this survey to fill out the questionnaire and undergo endoscopy. The result showed that heartburn was reported from 1,994 patients (42.2%) out of 4,723, and reflux esophagitis classified as grade A-D was reported from 602 patients (16.7%) out of 3,608. Meanwhile, fat intake, sweet food and anti-inflammatory analgesics were proven to be causes of heart-burn. Furthermore, frequency of heartburn and severity of reflux esophagitis were slightly correlated, although those were not necessarily obviously related.

Adult↗
PubMed2004

An animal model study to clarify and investigate endoscopic tissue coagulation by using a new monopolar device.

BACKGROUND: The purpose of this study was to evaluate a new device for endoscopic monopolar electrocoagulation and to develop ablative techniques by using this new device. METHODS: The new device consists of an overtube with a wire mesh electrode in an oval opening in the distal end and a balloon at the distal end. High-frequency electrical current was applied in 5 animal (swine) esophagi by using this specially designed monopolar electrocoagulation device. A total of 32 "lesions" were ablated by using blend electrosurgical waveforms for different time durations. The esophagi were then resected for histopathologic evaluation. RESULTS: Histopathologic study of the ablated lesions demonstrated that, by using the monopolar electrocoagulation device, different levels of degeneration of the mucosa and submucosa were achieved. The method for use of the device is fast and easy to apply. CONCLUSIONS: The ablative procedure with the new overtube device is minimally invasive, clearly feasible, and easy to apply. This new device potentially can be used in patients for tissue ablation.

Animals↗
PubMed2004

The expressions of p21 and pRB may be good indicators for the sensitivity of esophageal squamous cell cancers to CPT-11: Cell proliferation activity correlates with the effect of CPT-11.

Previously, we demonstrated that CPT-11 is an effective agent against esophageal squamous cell cancers (ESCC), and that the protein level of DNA topoisomerase I can be a predictor for sensitivity to CPT-11 (Jpn J Cancer Res 2001; 92: 1335-41). Here, we describe our search for additional predictors of sensitivity to CPT-11, mainly among cell cycle-regulating proteins, because the cytotoxicity of CPT-11 is significantly correlated with the percentage of ESCC cells in S-phase. To this end, we selected and examined the expressions of 5 proteins involved in G1-S transition, i.e., p53, cyclin D1, p21, p27, and pRB, in 14 ESCC cell lines by western blot analysis. Among these proteins, the expression levels of p21 and pRB showed significant differences that were associated with the IC50 values for CPT-11 (P = 0.0339 and P = 0.0109, respectively). Namely, the expression of p21 or pRB independently could be a good indicator of CPT-11 efficacy in ESCC. In addition, the cell proliferation activities examined by enzyme-linked immunosorbent assay (ELISA) using 5-bromo-2'-deoxyuridine (BrdU) showed a significant correlation with the percentage of total S-phase cells (correlation coefficient = 0.568, P = 0.0324), and an inverse correlation with the IC50 values for CPT-11 (correlation coefficient =-0.601, P = 0.0213). Because, as in the case of DNA topoisomerase I, the cell proliferation activity determined using BrdU shows a close relationship with the MIB-1 labeling index, immunohistochemical studies of p21, pRB, and MIB-1 in resected ESCC specimens and/or biopsy samples could make it possible to predict more precisely the sensitivity of ESCC patients to CPT-11 prior to treatment.

Adenovirus E1A Proteins↗
PubMed2004

[Laparoscopic surgery for gastric cancer].

Recently, the treatment of gastric cancer is becoming diversified. In Japan, gastrectomy with D2 lymphadenectomy has been recognized as a standard operation and has been performed widely for years. However, instead of D2 conventional gastric resection, various treatments using endoscopic or laparoscopic methods have been developed. Their usefulness and safety have been established, and the rate of detection of early gastric cancer has risen with the progress of medical technology and systems. The treatment suitable for the given stage must be chosen. In our department, we introduced laparoscopic operations and considered their usefulness and indication. Now, laparoscopic gastrectomy is recommended for cases in cStage I A and cStage I B of the guideline proposed by the Japanese Gastric Cancer Society. Future randomized controlled trials consisting of open surgery and laparoscopic gastrectomy are warranted.

Gastrectomy↗
PubMed2003

[Progress of diagnosis for esophageal cancer].

Although the possible existence of micrometastasis in superficial esophageal cancer cases is the most important factor in deciding the therapeutic strategy, it is difficult. There are also limits to the diagnosis of the depth of tumor invasion by endoscopy and EUS. Therefore, the extension of the indication of EMR is planned. Then, the complement of diagnostic ability by EMR is being tried. Sentinel lymph node (s) identification and its biopsy also seem to be useful. In advanced esophageal cancer cases, diagnostic accuracy has been improving by speedup of CT and MRI scans and various image processing technology. More accurate diagnosis of metastasis using PET is much awaited. However, there is still insufficient ability to detect micrometastasis to date. Molecular bio-markers with comprehensiveness are not a valuable selection at this stage. Although advanced equipment has brought more diagnostic accuracy, ways to integrate or use these tools at the clinical level are sought. Some equipment developing and how to integrate them and how to select the appropriate examination in each patient are problems which are required in clinical practitioners.

Biomarkers, Tumor↗
PubMed2002

Evaluation of an indicator for lymph node metastasis of esophageal squamous cell carcinoma invading the submucosal layer.

Lymph node metastasis is a major prognostic factor for esophageal squamous cell carcinoma (ESCC). In recent years, endoscopic mucosal resection (EMR) has been developed with excellent results for the treatment of the superficial ESCC. To make the EMR treatment successful, it is important to establish a good indicator to identify ESCC patients at a high risk of lymph node metastasis. In this study, we examined clinicopathological and immunohistochemical factors to investigate the factors involved in lymph node metastasis of ESCC invading to the submucosal layer (sm-ESCC). Surgical specimens from 84 sm-ESCC patients were examined. Among 84 sm-ESCC patients, 33 (39.3%) had lymph node metastases. Clinicopathologically, tumor depth, lymphatic invasion and blood vessel invasion showed significant correlations with lymph node metastasis by univariate analysis. Tumor depth and lymphatic invasion showed significant correlations by multivariate analysis of these factors. Immunohistochemically, P53 accumulation was observed in 45 cases (53.6%), cyclin D1 overexpression in 25 (29.8%), and pRB in 65 (77.4%). P53 accumulation, cyclin D1 overexpression and MIB-1 Labeling Index were significantly associated with lymph node metastasis by univariate analysis, and P53 accumulation showed a significant correlation with lymph node metastasis by multivariate analysis. Among tumor depth, lymphatic invasion and P53 accumulation, tumor depth and lymphatic invasion were significantly correlated with lymph node metastasis (P = 0.0023 and P = 0.0092, respectively) by multivariate analysis. These data suggest that tumor depth and lymphatic invasion can be considered as good indicators for lymph node metastasis among patients with sm-ESCC. In addition, P53 accumulation could be helpful to identify the patients who need additional treatment after EMR.

Adult↗