Endoscopic submucosal dissection for large superficial colorectal tumors using the "clip-flap method".

BACKGROUND AND STUDY AIMS: Endoscopic submucosal dissection (ESD) is technically difficult because of poor visualization and instability in the cutting area. Although mucosal flap formation improves visualization of the cutting area, it is difficult to achieve, especially in colorectal ESD. To facilitate mucosal flap formation, we developed the "clip-flap method" by substituting an endoclip for the mucosal flap until it is formed. PATIENTS AND METHODS: The clip-flap method was applied to 114 of 119 large superficial colorectal tumors being treated by ESD. Therapeutic efficacy and safety were assessed. RESULTS: Mean tumor diameter, resected specimen diameter, and procedure time were 32.5 mm, 38.9 mm, and 82.0 minutes, respectively. The en bloc resection rate was 97.5 %. Intraoperative perforation occurred in one patient who was treated conservatively. A single endoclip was used for 92 lesions and improved visualization of the cutting area. A cross pattern of endoclips was used for 22 lesions and further stabilized the visual field, especially near the lateral side. CONCLUSIONS: The clip-flap method is a simple, safe, and effective option for ESD of large superficial colorectal tumors.

[A case of exfoliative esophagitis caused by endoscopic submucosal dissection during imatinib treatment for gastrointestinal stromal tumor].

A woman in her seventies with multiple early stage (0-IIa) gastric cancers was undergoing imatinib therapy for gastrointestinal stromal tumor. Subsequently, she underwent 2-stage endoscopic submucosal dissection (ESD) for these cancers. Both procedures were successful, but she developed exfoliative esophagitis as a complication after the first ESD. To prevent this complication after the second ESD, we used a longer imatinib withdrawal period before the procedure and used general anesthesia during ESD. Although the patient developed exfoliative esophagitis after the second ESD, but its severity was less than that after the first procedure. Only a few studies have reported endoscopic therapy-induced exfoliative esophagitis. We suggest that this complication may be related to imatinib-induced mucosal damage.

Short-term outcomes of endoscopic submucosal dissection (ESD) for early gastric neoplasm: multicenter survey by osaka university ESD study group.

BACKGROUND: Endoscopic submucosal dissection (ESD) was developed for en bloc removal of large and flat gastrointestinal tract neoplasms. In Japan, ESD is performed under conscious sedation. The risks for sedation-related complications of ESD, such as postoperative pneumonia, have not been evaluated. The aim of this study was to evaluate the incidence of postoperative pneumonia after ESD in a multicenter survey. PATIENTS AND METHODS: A total of 1188 patients with upper gastric neoplasms treated with ESD in nine hospitals were enrolled from May 2003 to September 2008. The en bloc resection rates and complications (bleeding, perforation, and postoperative pneumonia) were assessed. The correlations between the clinical variables and complications were investigated using logistic regression models. RESULTS: The en bloc resection rate was 95.3%. Bleeding, perforation, and pneumonia occurred in 37 (3.1%), 49 (4.1%), and 19 (1.6%) patients, respectively. Univariate analysis indicated that procedure time, but not specimen size, or patient age, or sex, was significantly related to bleeding and perforation. The incidence of pneumonia was higher in patients with ulceration, older patients (≥75years), and those with a long procedure duration (≥5h). CONCLUSION: The incidence of pneumonia, but not perforation and bleeding, after ESD, is high in older patients (≥75years). Special care should be taken with older patients undergoing ESD to minimize the risk of postoperative pneumonia.

[A bowel perforation with metallic stent placement for advanced rectal cancer during bevacizumab-based chemotherapy].

A 61-year-old woman with an unresectable malignant rectal stricture underwent placement of an expandable metallic stent under endoscopic guidance. The stent was successfully implanted and her bowel obstruction was relieved. After treatment with bevacizumab for unresectable rectal cancer, she was admitted to our hospital because of rectal perforation. This case suggests that placement of a metallic stent in colorectal cancer cases may increase the risk of bowel perforation during bevacizumab-based chemotherapy.

Epidermal growth factor inhibits the growth of TE8 esophageal cancer cells through the activation of STAT1.

BACKGROUND: Epidermal growth factor receptors (EGFRs) mediate growth signals in a variety of normal and malignant cells. However, the issue of whether the EGF/EGFR system contributes to the progression of esophageal cancer cells remains controversial. The aim of the present study was to determine the role of EGFR in the growth of esophageal cancer cell lines. METHODS: Three esophageal cancer cell lines, TE1, TE2, and TE8, were stimulated with EGF, and cellular growth was then evaluated by cell number. The activation of signal transducers and activators of transcription (STATs) and the expression of the cyclin-dependent kinase (CDK) inhibitor p21/WAF1 were determined by an electromobility shift assay and Northern blot analysis, respectively. RESULTS: EGF inhibited the growth of TE8 cells, while no significant effects were observed for TE1 and TE2 cells. The treatment of TE8 cells with EGF induced the activation of STAT1 and STAT3, followed by the expression of p21/WAF1. The introduction of a dominant-negative STAT1 construct into TE8 cells abolished not only growth inhibition but also p21/WAF1 induction by EGF. CONCLUSIONS: The findings herein suggest that EGF inhibits the growth of some esophageal cancer cells that overexpress EGFR and that the activation of STAT1 constitutes a critical event which is required for the inhibition of growth by EGF.

Comparative study of esomeprazole and lansoprazole in triple therapy for eradication of Helicobacter pylori in Japan.

AIM: To evaluate the efficacy and safety of esomeprazole-based triple therapy compared with lansoprazole therapy as first-line eradication therapy for patients with Helicobacter pylori (H. pylori) in usual post-marketing use in Japan, where the clarithromycin (CAM) resistance rate is 30%. METHODS: For this multicenter, randomized, open-label, non-inferiority trial, we recruited patients (≥ 20 years of age) with H. pylori infection from 20 hospitals in Japan. We randomly allocated patients to esomeprazole therapy (esomeprazole 20 mg, CAM 400 mg, amoxicillin (AC) 750 mg for the first 7 d, with all drugs given twice daily) or lansoprazole therapy (lansoprazole 30 mg, CAM 400 mg, AC 750 mg for the first 7 d, with all drugs given twice daily) using a minimization method with age, sex, and institution as adjustment factors. Our primary outcome was the eradication rate by intention-to-treat (ITT) and per-protocol (PP) analyses. H. pylori eradication was confirmed by a urea breath test from 4 to 8 wk after cessation of therapy. RESULTS: ITT analysis revealed the eradication rates of 69.4% (95%CI: 61.2%-76.6%) for esomeprazole therapy and 73.9% (95%CI: 65.9%-80.6%) for lansoprazole therapy (P = 0.4982). PP analysis showed eradication rate of 76.9% (95%CI: 68.6%-83.5%) for esomeprazole therapy and 79.8% (95%CI: 71.9%-86.0%) for lansoprazole therapy (P = 0.6423). There were no differences in adverse effects between the two therapies. CONCLUSION: Esomeprazole showed non-inferiority and safety in a 7 day-triple therapy for eradication of H. pylori compared with lansoprazole.

Difference in bacterial motion between forward and backward swimming caused by the wall effect.

A bacterial cell that has a single polar flagellum alternately repeats forward swimming, in which the flagellum pushes the cell body, and backward swimming, in which the flagellum pulls the cell body. We have reported that the backward swimming speeds of Vibrio alginolyticus are on average greater than the forward swimming speeds. In this study, we quantitatively measured the shape of the trajectory as well as the swimming speed. The trajectory shape in the forward mode was almost straight, whereas that in the backward mode was curved. The same parameters were measured at different distances from a surface. The difference in the motion characteristics between swimming modes was significant when a cell swam near a surface. In contrast, the difference was indistinguishable when a cell swam >60 microm away from any surfaces. In addition, a cell in backward mode tended to stay near the surface longer than a cell in forward mode. This wall effect on the bacterial motion was independent of chemical modification of the glass surface. The macroscopic behavior is numerically simulated on the basis of experimental results and the significance of the phenomenon reported here is discussed.