Postpolypectomy bleeding of colorectal polyps in patients with continuous warfarin and short-term interruption of direct oral anticoagulants.

BACKGROUND AND AIMS: Postpolypectomy bleeding (PPB) is the most common adverse event after colorectal polypectomy. Use of anticoagulants is an important risk factor for PPB. This study aimed to evaluate PPB in patients receiving treatment with warfarin and direct oral anticoagulants (DOACs). METHODS: Between August 2017 and July 2019, 5449 patients with 12,601 polyps who underwent endoscopic snare resection of colorectal polyps were enrolled. Endoscopic snare resection was performed in patients receiving continuous warfarin (C-warfarin) and in patients who experienced 1 day cessation of (O-) of DOACs in accordance with the Japanese Gastroenterological Endoscopy Society guidelines. RESULTS: The PPB rate in the group receiving anticoagulants was statistically higher than that in the group without anticoagulants (8.5% [33/387] vs 1.2% [63/5,062], respectively; P < .001). By multivariate logistic regression analysis, male gender (odds ratio [OR], 2.17; P = .007), warfarin (OR, 4.64; P < .001), DOACs (OR, 6.59; P < .001), and multipolyp removal (OR, 1.77; P = .007) were significant risk factors for PPB. PPB was observed in 9 and 21 patients in the C-warfarin and O-DOACs groups, respectively: C-warfarin (8.0% [9/113]), O-dabigatran (6.1% [2/33]), O-rivaroxaban (14.8% [9/61]), O-apixaban (9.8% [9/92]), and O-edoxaban (1.8% [1/56]). The PPB rate with the O-edoxaban group was significantly lower than that with the O-rivaroxaban group (P < .05). CONCLUSIONS: Use of anticoagulant therapy was an independent risk factor for PPB. The rates of PPB in patients receiving C-warfarin and O-DOACs were also higher than those in patients not receiving anticoagulants. Edoxaban may be safe through short-term withdrawal in patients undergoing endoscopic snare resection of colorectal polyps.

A multicenter retrospective study of the esophageal triamcinolone acetonide-filling method in patients with extensive esophageal endoscopic submucosal dissection.

OBJECTIVE: Endoscopic submucosal dissection (ESD) for extensive esophageal cancer is sometimes associated with post-ESD stenosis, despite preventative steroid therapy. In this retrospective multicenter analysis, we evaluated the factors associated with therapy resistance. MATERIALS AND METHODS: We enrolled 73 patients with 75 extensive esophageal cancers treated with ESD. Stenosis prevention was performed using two esophageal triamcinolone acetonide (TA)-fillings, and repeated if stenosis was found on follow-up. Therapy-resistance factors associated with incidence of severe stenosis requiring endoscopic balloon dilation (EBD) were evaluated, including age, gender, previous treatment history, tumor location, morphology, resection size, histologic type, invasion depth, and horizontal resection grade (HR-grade 1, ≥ 9/12 and <10/12 of the circumference; grade 2, ≥ 10/12 and <11/12; grade 3, ≥ 11/12 but not circumferential; and grade 4, entirely circumferential). RESULTS: Severe stenosis occurred in 17.3%(13/75) of cases, with a median of two EBDs (range, 1-6 times). Severe stenosis was significantly associated with HR-grade elevation and previous treatment history (p < .05); multivariate analysis showed both as independent therapy-resistance factors (p < .05). Patients without previous treatment history demonstrated severe stenosis at 12.9%(9/70): 0%(0/26) HR-grade 1, 18.8%(3/16) grade 2, 17.6%(3/17) grade 3, and 27.3%(3/11) grade 4, showing a risk of HR-grade 2 or more resection but an acceptable stenosis prevention even after entirely circumferential resection. Conversely, patients with previous treatment history demonstrated severe stenosis at a high frequency of 80%(4/5). CONCLUSIONS: Esophageal TA-filling is a promising stenosis-preventive steroid therapy, even in entirely circumferential ESD cases. However, HR-grade 2 or more elevation and previous treatment history were independently associated with therapy resistance.

Relationship between colonic diverticulosis and colon neoplasms in Japanese patients.

BACKGROUND AND AIM: Colonic diverticulosis (CD) has been reported to be associated with presence of colon neoplasms (CNs) in Western patients, since most of the associated risk factors are common between them. However, such correlation has not been fully investigated in Asian patients. In this study, the association of CNs with CD was evaluated in a multicenter investigation. METHODS: We enrolled 5633 patients who underwent both colonoscopy and esophagogastroduodenoscopy due to annual follow-up, screening for positive occult blood testing and abdominal symptoms between January 2016 and December 2017 at three institutions. The relationship between the presence of CNs and CD was investigated, and predictors for presence of CNs were determined by multivariate logistic analysis. RESULTS: The enrolled patients consisted of 1799 (31.9%) with CD (average age 70.0 years, male 64.0%) and 3834 without CD (66.0 years, male 52.9%), with the prevalence of CNs in those groups 46.6% and 44.2%, respectively (P = 0.090). Predictors for early colon cancer were shown to be age (OR 1.02, 95% CI 1.01-1.04, P = 0.010), laxatives use (OR 1.76, 95% CI 1.17-2.64, P = 0.007), gastric neoplasms (OR 2.16, 95% CI 1.23-3.81, P = 0.008), and CD (OR 1.64, 95% CI 1.16-2.31, P = 0.005). Early colon cancer in the distal colon was most frequently detected in patients with right-sided CD (RR 2.50, P = 0.001). CONCLUSION: In Japanese patients, early colon cancer was more frequently found in those with as compared to those without CD. The presence of CD may be an important indicator for an index colonoscopy examination to detect colon cancer. (Clinical-trial-registry: UMIN000038985).

Prospective multicenter study of the esophageal triamcinolone acetonide-filling method in patients with subcircumferential esophageal endoscopic submucosal dissection.

BACKGROUND AND AIM: The esophageal triamcinolone acetonide (TA)-filling method is a novel local approach for stenosis prevention after extensive esophageal endoscopic submucosal dissection (ESD). We evaluated this method after subcircumferential ESD. METHODS: We enrolled 20 patients with esophageal cancer requiring subcircumferential ESD in a prospective multicenter study. Esophageal TA filling was carried out 1 day and 1 week after ESD, with follow-up endoscopy every 2 weeks. We treated severe stenosis preventing endoscope passage with endoscopic balloon dilatation (EBD) and additional TA filling, and mild stenosis allowing endoscope passage with additional TA filling only. Primary endpoint was incidence of severe stenosis; secondary endpoints were total number of EBD, rate of additional TA filling, time to stenosis and complete re-epithelialization, dysphagia score, and adverse events. Horizontal resection grade was divided into grades 1 (≥ 9/12 and <10/12 of the circumference), 2 (≥ 10/12 and <11/12), and 3 (≥ 11/12 but not circumferential) and analyzed statistically for correlation with endpoints. RESULTS: Incidence of severe stenosis was 5.0% (1/20; 0.1-24.8%) and was treated with three EBD. Six patients showed mild stenosis. Additional TA filling was carried out in these seven patients: 0% (0/9) for grade 1 resection, 40% (2/5) for grade 2, and 83% (5/6) for grade 3 (P < 0.05). Median time to stenosis and re-epithelialization was 3 and 7 weeks, respectively. Dysphagia score deteriorated in one patient. No adverse events occurred. CONCLUSIONS: The esophageal TA-filling method prevented stenosis after subcircumferential ESD. Grade ≥2 resection showed a high risk for stenosis, but additional TA filling for mild stenosis inhibited stenosis progression (UMIN000024384).

Capabilities of fecal calprotectin and blood biomarkers as surrogate endoscopic markers according to ulcerative colitis disease type.

Fecal calprotectin level in ulcerative colitis patients is correlated with endoscopic findings. However, its association with various ulcerative colitis disease types has not been elucidated. In the present study, we investigated the correlation of fecal calprotectin level with endoscopic findings as compared to blood biomarkers according to ulcerative colitis disease type. Fecal calprotectin as well as the blood biomarkers: C-reactive protein (CRP), white blood count (WBC), erythrocyte sedimentation rate (ESR), hemoglobin, platelet count (PLT), and serum albumin (Alb) were measured in patients who underwent a complete colonoscopy. Disease type was divided into proctitis, left-sided colitis, and extensive colitis. Correlations of fecal calprotectin and blood biomarker levels with Mayo endoscopic subscore were analyzed. A total of 186 colonoscopy examinations were performed in 124 patients with ulcerative colitis. Fecal calprotectin level showed a significant correlation with Mayo endoscopic subscore regardless of disease type (proctitis, r = 0.54, p<0.01; left-sided colitis, r = 0.75, p<0.01; extensive colitis, r = 0.78, p<0.01), and clearly discriminated inactive (Mayo endoscopic subscore 0) from active stages (Mayo endoscopic subscore 1-3). On the other hand, none of the examined blood biomarkers showed a correlation with Mayo endoscopic subscore in the proctitis group, while weak correlations of several biomarkers (CRP, WBC, ESR, PLT and Alb) with Mayo endoscopic subscore were found in left-sided colitis and extensive colitis cases. This is the first report to elucidate the capabilities of fecal calprotectin and blood biomarkers as endoscopic surrogate markers according to ulcerative colitis disease type.

Inter-institutional variations regarding Barrett's esophagus diagnosis.

BACKGROUND: Barrett's esophagus (BE) is a known precursor for development of esophageal adenocarcinoma and surveillance of affected patients is necessary when cancer progression risk is considered to be high. However, the accuracy of BE diagnosis may not be homogenous among institutions with endoscopy units. We investigated inter-institutional variability by examining the accuracy of endoscopic diagnosis of BE at 4 different hospitals. METHODS: The accuracy of BE diagnosis at the 4 hospitals was retrospectively reviewed by 6 expert endoscopists, who independently reviewed endoscopic images of approximately 500 consecutive patients examined at each hospital without information regarding the diagnosis by the on-site endoscopists. When the expert reviewers made different diagnosis, a final diagnosis was made by consensus. That was then compared with the diagnosis of the attending endoscopists at each hospital and their concordance was calculated separately for each endoscopy unit. In addition, the relationship between diagnostic accuracy and endoscopic experience was assessed. RESULTS: The prevalence of BE diagnosis by the on-site endoscopists was not homogenous and varied widely (17.2-96.8%). In 1 hospital, over-diagnosis was the cause of dissimilarity, while under-diagnosis was the cause in two hospitals. Diagnostic accuracy by the attending endoscopists in all 4 hospitals ranged from 44.6 to 83.1% (P < 0.05). There was no significant association between diagnostic accuracy and endoscopic experience or board licensing status of the on-site endoscopists. CONCLUSION: Diagnostic accuracy for BE was not homogenous among 4 hospitals, and problems related to over- and under-diagnosis should be considered.

Bleeding Risk Related to Upper Gastrointestinal Endoscopic Biopsy in Patients Receiving Antithrombotic Therapy: A Multicenter Prospective Observational Study.

BACKGROUND: Although antithrombotic agents are widely used for cardiac and cerebrovascular disease prevention, they increase the risk of gastrointestinal (GI) bleeding. OBJECTIVE: To examine GI bleeding risk in association with an esophagogastroduodenoscopy (EGD) biopsy performed in patients without cessation of antithrombotic therapy. METHODS: This study was prospectively conducted at 14 centers. EGD biopsies were performed in patients receiving antithrombotic agents without cessation, as well as age- and sex-matched controls not receiving antithrombotic therapy. Patients treated with warfarin before the biopsy had a prothrombin time-international normalized ratio level <3.0. The proportion of GI bleeding events was compared between the groups. RESULTS: The patient group (n = 277) underwent a total of 560 biopsies while continuing antithrombotic therapy, of whom 24 were receiving multiple antiplatelet drugs, and 9 were receiving both antiplatelet and anticoagulant agents. The control patients (n = 263) underwent 557 biopsies. The upper-GI bleeding rate within 30 days after the EGD biopsy did not increase in patients without cessation of antithrombotic treatment, regardless of receiving single or multiple antithrombotic agents. CONCLUSIONS: We found no significant increase in upper-GI bleeding risk following an EGD biopsy in patients taking antithrombotic agents, suggesting its safety without the need for antithrombotic treatment interruption.

Bile acids induce Delta-like 1 expression via Cdx2-dependent pathway in the development of Barrett's esophagus.

Crosstalk between the Notch signaling pathway and Caudal-related homeobox 2 (Cdx2) has important roles in the development of Barrett's esophagus (BE). We investigated the expression and function of the Notch signaling ligand Delta-like 1 (Dll1) during the development of BE. We determined the expression levels of Dll1 and intracellular signaling molecules related to Notch signaling ((Notch1, Hairy/enhancer of split 1 (Hes1), and Atonal homolog 1 (ATOH1)) in human esophageal squamous and Barrett's epithelium samples. Next, those expression levels in esophageal squamous cells (Het-1A) and Barrett's esophageal cells (CP-A and BAR-T) following stimulation with either bile acids or gamma-secretase inhibitor were investigated. Finally, changes in those expression levels following transfection of a Cdx2 or Dll1 expression vector into Het-1A cells were examined. In addition, changes in those expression levels following knockdown of Cdx2 or Dll1 in CP-A cells were also examined. Dll1 was found to be upregulated and localized in the cell membrane and cytoplasm in BE. Bile acids enhanced cytoplasmic expression of Dll1 in CP-A cells, while cleaved Notch1 expression did not change, suggesting lack of a Dll1 agonistic effect on Notch signaling. Cells transfected with Cdx2 revealed significantly enhanced Dll1, while forced expression of Dll1 enhanced ATOH1, Cdx2, and MUC2 expression levels. Nevertheless, enhanced Dll1 did not induce Hes1 expression, suggesting that Dll1 may primarily function as an intracellular signaling molecule and not a Notch agonistic ligand in the canonical pathway. In addition, knockdown of Cdx2 completely abrogated any increase in Dll1 expression upon treatment with bile acids. Our results revealed a novel function of Dll1: facilitation of intestinal metaplasia in conjunction with Cdx2 expression. Furthermore, they suggest that intracellular induction of Dll1 expression in esophageal epithelial cells due to Cdx2 induction in response to bile acids has important roles in BE development.

Fecal calprotectin level correlated with both endoscopic severity and disease extent in ulcerative colitis.

BACKGROUND: The relationship between fecal calprotectin (FC) and disease extent in ulcerative colitis (UC) has not been fully elucidated. The aim of this study was to clarify the correlation of FC with disease extent and severity in UC patients. METHODS: UC patients scheduled to undergo an ileocolonoscopy were enrolled and fecal samples for FC measurement were collected prior to the procedure. A Mayo endoscopic subscore (MES) was determined for each of 5 colonic segments. To evaluate the association of FC with extent of affected mucosa as well as disease severity, we assessed the correlation of FC level with the sum of MES (S-MES) for the 5 colonic segments as compared to the maximum score of MES (M-MES). RESULTS: FC measurements in conjunction with findings from 136 complete colonoscopies in 102 UC patients were evaluated. FC level showed a stronger correlation with S-MES (correlation coefficient r = 0.86, p < 0.001) as compared to M-MES (r = 0.79, p < 0.001). In patients with an M-MES of 1, 2, and 3, FC level showed a significant correlation with S-MES (r = 0.67, p < 0.001; r = 0.70, p < 0.001; r = 0.47, p = 0.04, respectively). Our findings indicate that FC level is elevated in patients with greater areas of affected mucosa even in those with the same M-MES value. CONCLUSIONS: FC level was shown to be correlated with the extent of affected mucosa as well as severity in UC patients, thus it is useful for precise assessment of mucosal inflammation.

Downregulation of serotonin reuptake transporter gene expression in healing colonic mucosa in presence of remaining low-grade inflammation in ulcerative colitis.

BACKGROUND AND AIM: The serotonin reuptake transporter (SERT) terminates serotonin activity by removing it from interstitial space. Downregulated colonic SERT expression has been reported in irritable bowel disease (IBS), and symptoms resembling IBS occur in cases of inflammatory bowel disease (IBD) in remission; thus, a common pathogenesis for IBS and IBD is possible. However, little is known regarding SERT expression in colonic mucosa of IBD patients during healing. METHODS: Twenty-two ulcerative colitis (UC) patients underwent colonoscopy examinations, during which inflamed mucosa was distinguished from that undergoing healing. Healing mucosa was classified into regular and irregular vessel patterns by narrowband imaging magnifying colonoscopy. Expressions of SERT and various inflammation-related genes in biopsy samples were assessed using a polymerase chain reaction array system and real-time polymerase chain reaction. Colitis model mice were established by administration of dextran sodium sulfate or transfer of CD4(+) T cells isolated from SAMP1 mice, then time-course changes of SERT and inflammatory gene expressions were observed in colonic mucosa. RESULTS: In UC patients, SERT expression in inflamed mucosa was significantly lower than in healing mucosa. SERT expression was decreased in healing mucosa with an irregular vessel pattern with mildly increased levels of inflammatory gene expression. In mice, SERT expression was suppressed in inflamed mucosa and continuously observed with low-grade mucosal inflammation during colitis healing. CONCLUSIONS: Sserotonin reuptake transporter expression is downregulated in healing colonic mucosa of UC patients and that suppression may be dependent on the presence of remaining low-grade colonic inflammation.

Usefulness of computed tomography with air insufflation of the stomach prior to percutaneous endoscopic gastrostomy procedure.

We examined the results of computed tomography (CT) with and without air insufflation of the stomach prior to performing percutaneous endoscopic gastrostomy (PEG). We retrospectively analyzed 366 patients who underwent PEG. CT images obtained with and without air insufflation were examined for the presence or absence of contact between the gastric anterior wall and abdominal wall. PEG outcome based on CT findings was also examined. CT with and without air insufflation was performed in 272 and 94 patients, respectively. Contact between the gastric anterior wall and abdominal wall was shown in 254 (93.4%) with and 45 (47.9%) without air insufflation, all of whom underwent a successful PEG procedure. In patients without contact between the gastric anterior wall and abdominal wall, PEG was not successful in 3 of 49 (6.1%) examined by CT without and 6 of 18 (33.3%) examined with air insufflation (p = 0.004). Values for diagnostic accuracy for contact between the gastric anterior wall and abdominal wall shown by CT with and without air insufflation in successful PEG cases were 0.96 and 0.51, respectively. In conclusion, CT with air insufflation more often revealed contact between the gastric anterior wall and abdominal wall as compared to CT without air insufflation, which may help to predict PEG procedure success.

Magnification endoscopy with acetic acid enhancement and a narrow-band imaging system for pit pattern diagnosis of colorectal neoplasms.

BACKGROUND AND GOALS: Pit pattern (PP) analysis of colorectal neoplasms using magnification chromoendoscopy with crystal violet (CV-MCE) is useful for predicting histologic features, but it is time consuming. Capillary pattern analysis by magnification endoscopy with narrow-band imaging (NBIME) is a useful and simpler procedure, but its diagnostic accuracy may be inferior to CV-MCE. NBIME with acetic acid enhancement (A-NBIME) is effective for rapid visualization of gastric mucosal microstructures. We performed a prospective study to compare the diagnostic reliability and feasibility of A-NBIME and CV-MCE in PP diagnosis of colorectal neoplasms. STUDY: The present study consisted of 3 protocols: Study-1 assessed 56 colorectal lesions photographed with A-NBIME and CV-MCE, and the endoscopic images were reviewed by 3 experts to compare the diagnostic concordance; study-2 assessed 202 colorectal lesions photographed with A-NBIME in 116 consecutive patients and the correlation between PP and histologic findings; study-3 randomly allocated 100 patients with colorectal lesions equally to A-NBIME and CV-MCE, and compared the procedure time and visible ratio of PP. RESULTS: The κ value for interobserver agreement for A-NBIME and CV-MCE was 0.71 (0.66 to 0.75) and 0.80 (0.75 to 0.85), respectively. Intraobserver agreement between modalities for each reviewer was 0.79 (0.70 to 0.88), 0.80 (0.71 to 0.90), and 0.74 (0.67 to 0.82). Non-neoplastic polyps and massively invasive submucosal adenocarcinomas were statistically related to type II and type VI-H/VN. The procedure time was statistically shorter with A-NBIME than with CV-MCE (31 vs. 81 s), and the visible ratio of PP was equivalent (98.9% vs. 98.3%). CONCLUSIONS: A-NBIME is comparable with CV-MCE in PP diagnosis of colorectal neoplasms and is a simpler technique.

Prevalence of irritable bowel syndrome-like symptoms in ulcerative colitis patients with clinical and endoscopic evidence of remission: prospective multicenter study.

OBJECTIVE: Irritable bowel syndrome (IBS)-like symptoms are often found in ulcerative colitis (UC) patients in remission. However, the prevalence of those symptoms in UC patients with endoscopic evidence of remission shown by mucosal healing remains unknown. MATERIAL AND METHODS: IBS diagnosis was evaluated by questionnaire results according to the Rome III criteria. Clinical remission was assessed by clinical activity index (CAI), whereas endoscopic remission was evaluated by endoscopic index (Matts grade). RESULTS: We enrolled 172 patients in clinical remission (CAI ≤ 4), after excluding 36 for incomplete questionnaire results or nonremission findings, as well as 330 control subjects. Of the 172 UC patients, 46 (26.7%) met the Rome III criteria, which was a significantly higher rate as compared with the controls (4.8%). The prevalence rate of IBS-like symptoms in UC patients with endoscopic remission findings (Matts grade ≤2) was 25.6%, which was similar to that of those with clinical remission. When endoscopic remission was defined as Matts grade 1, the prevalence rate of IBS-like symptoms was decreased to 15.4%, although the prevalence rate remained higher than that of the control subjects. CONCLUSIONS: The prevalence of IBS-like symptoms in UC patients with clinical and endoscopic remission findings was significantly higher than that of control subjects. Furthermore, the prevalence rate in patients with complete endoscopic remission was decreased. These findings suggest that residual low-grade inflammation may influence the presence of IBS-like symptoms in UC patients in remission.

Reliability of symptoms and endoscopic findings for diagnosis of esophageal eosinophilia in a Japanese population.

BACKGROUND/AIMS: The clinical characteristics of esophageal eosinophilia (EE), which is essential for diagnosis of eosinophilic esophagitis (EoE), have not been fully clarified in a Japanese population. The aim of this study was to analyze the reliability of symptoms and endoscopic findings for diagnosing EE in Japanese individuals. METHODS: We prospectively enrolled subjects who complained of esophageal symptoms suggesting EoE and/or those with endoscopic findings of suspected EoE at the outpatient clinics of 12 hospitals. Diagnostic utility was compared between the EE and non-EE groups using logistic regression analysis. RESULTS: A total of 349 patients, including 319 with symptoms and 30 with no symptoms but endoscopic findings suggesting EoE were enrolled. Of those with symptoms, 8 (2.5%) had EE, and 3 were finally diagnosed with EoE. Of those without symptoms but endoscopic findings, 4 had EE. Among 8 symptomatic patients, 7 had abnormal endoscopic findings suspicious of EoE. Although dysphagia was a major symptom in EE, none of the presenting symptoms was useful for diagnosis of EE. Among the endoscopic findings, linear furrow was the most reliable (OR = 41.583). CONCLUSION: EE is uncommon among patients with esophageal symptoms in Japanese individuals. The most useful endoscopic finding for diagnosis of EE was linear furrow, whereas subjective symptoms were not supportive.

Pathogenesis of irritable bowel syndrome--review regarding associated infection and immune activation.

There is increasing evidence regarding the role of immune activation in the etiology of irritable bowel syndrome (IBS), which has been mainly been shown in studies investigating mechanisms of postinfectious IBS (PI-IBS). Exposure to intestinal infection induces persistent low-grade systemic and mucosal inflammation, which is characterized by an altered population of circulating cells, mucosal infiltration of immune cells and increased production of various cytokines in IBS patients. Recent studies have also indicated an increased innate immune response in these patients by evaluating expression and activation of Toll-like receptors (TLRs). These findings suggest that immune activation may play a crucial role in the pathogenesis of IBS. In addition, psychological stress has been reported to be one of the factors that induces immune activation. However, it remains unknown whether immune activation in IBS patients is largely dependent on infectious gastroenteritis and/or psychological stress. Additional studies are necessary to understand the precise mechanism of immune activation and its relationship to the development of IBS.

[Small bowel obstruction and gastric ulceration resulting from rice cake ingestion -computed tomography diagnosis in eight patients-].

Here we report the cases of eight patients who developed small bowel obstruction and/or gastric ulcers after ingesting rice cake, the traditional Asian food, and were managed conservatively. This report adds to the existing literature on gastrointestinal disorders induced by rice cake ingestion, which are characterized by gastrointestinal obstruction, perforation, and ulceration and are occasionally accompanied by peritonism. These conditions tend to occur in 50-60-year-old males who wear dentures or eat rapidly. Therapeutically, hard rice cake remnants in the upper gastrointestinal tract can be broken up by endoscopic snaring and can be detected by computed tomography as homogeneous high-density material at approximately 145 (range:120-206) Hounsfield units.

Gastric Flat Elevated Undifferentiated Signet-ring Cell Mucosal Cancer Lesion Detected in a Case without Helicobacter pylori Infection.

Protruded signet-ring cell carcinoma (SRCC) is extremely rare. We herein report a rare case of flat elevated gastric SRCC in a patient without Helicobacter pylori infection. Esophagogastroduodenoscopy of a woman in her 50s revealed a flat, whitish lesion in the gastric body with elevation. Histological results of an endoscopically biopsied specimen led to a diagnosis of SRCC. Resection using endoscopic submucosal dissection was performed, and histology results revealed that the tumor was localized in the lamina propria. The size was 10×6 mm, and a protrusion had been formed by SRCC enlargement without destruction of the surface epithelium structure.

Notch signaling pathway and Cdx2 expression in the development of Barrett's esophagus.

Cdx2 expression in esophageal stem cells induced by reflux bile acids may be an important factor for development of Barrett's esophagus, whereas Notch signaling is a molecular signaling pathway that plays an important role in the determination of cell differentiation. ATOH1 (a factor associated with Notch signaling) plays an important role in differentiation of stem cells into goblet cells. However, the relationship between the Notch signaling pathway and Cdx2 expression in the development of Barrett's esophagus has not been explored. The aim of this study was to investigate the interrelationship between Notch signaling and Cdx2 in esophageal epithelial cells. The expressions of Cdx2, MUC2, and intracellular signaling molecules related to Notch signaling (Notch1, Hes1, and ATOH1) were examined using real-time polymerase chain reaction (PCR) and immunohistochemical staining with biopsy specimens obtained from esophageal intestinal metaplasia (IM) with goblet cells (IM⁺) and columnar epithelium not accompanied by goblet cells (IM⁻). For in vitro experiments, we employed human esophageal epithelial cell lines (OE33, OE19, and Het-1A). After forced Cdx2 expression by applying a Cdx2 expression vector to the cells, changes in the expressions of Notch1, Hes1, ATOH1, Cdx2, and MUC2 were analyzed by real-time PCR and western blot analysis. Changes in expressions of Notch1, Hes1, ATOH1, Cdx2, and MUC2 in cells were analyzed following stimulation with bile acids in the presence or absence of Cdx2 blocking with Cdx2-siRNA. Suppressed Hes1 and enhanced ATOH1 and MUC2 expressions were identified in IM⁺ specimens. Forced expression of Cdx2 in cells suppressed Hes1, and enhanced ATOH1 and MUC2 expressions, whereas bile acids suppressed Hes1, and enhanced ATOH1, Cdx2, and MUC2 expressions. On the other hand, these effects were blocked by siRNA-based Cdx2 downregulation. Enhanced expression of Cdx2 by stimulation with bile acids may induce intestinal differentiation of esophageal columnar cells by interaction with the Notch signaling pathway.

Endoscopic characteristics of short-segment Barrett's esophagus, focusing on squamous islands and mucosal folds.

BACKGROUND AND AIM: Endoscopic definitions of Barrett's esophagus (BE) vary among countries, mainly because of the difficulty in diagnosing short-segment BE (SSBE) endoscopically. The aim of this study was to investigate whether the endoscopic identification of squamous islands and the specific position of columnar epithelium helps improve the diagnosis of SSBE. METHODS: First, we prospectively enrolled 100 consecutive patients with SSBE and evaluated the number of identified squamous islands in the columnar epithelium with different modalities: white light (WL), narrow band imaging (NBI), and iodine chromoendoscopy. Second, in another group of 100 consecutive patients with tongue-like SSBE, the correlation of the location of Barrett's mucosa to the esophageal longitudinal folds (ridge or valley) was evaluated endoscopically. RESULTS: It was possible to detect squamous islands in 48, 71, and 75 patients by WL, NBI, and iodine chromoendoscopy, respectively. The detection rate of squamous islands by NBI or iodine chromoendoscopy was significantly superior to that by WL. Tongue-like SSBEs were predominantly found on the ridge of mucosal folds (71%), similar to the location of mucosal breaks (84%). CONCLUSIONS: Squamous islands in the columnar epithelium were efficiently observed by NBI or iodine chromoendoscopy. SSBE was found more frequently on the ridges but not in the valleys of esophageal longitudinal mucosal folds. NBI endoscopic observation focusing on columnar epithelium with squamous islands on the ridges of distal esophageal folds may improve endoscopic detection of SSBE.

Capnographic monitoring for carbon dioxide insufflation during endoscopic submucosal dissection: comparison of transcutaneous and end-tidal capnometers [corrected].

BACKGROUND: The use of carbon dioxide (CO(2)) insufflation during endoscopic procedures is effective in reducing patient discomfort caused by bloating. However, transcutaneous arterial CO(2) (PtCO(2)) monitoring usually is required for safety during long endoscopic procedures. To evaluate a new capnometer for monitoring end-tidal carbon dioxide (EtCO(2)) concentrations and to compare PtCO(2) with EtCO(2) measured in the same patient, a prospective comparative study of EtCO(2) and PtCO(2) values measured simultaneously was designed. METHODS: The study enrolled 20 consecutive patients (18 men and two women; mean age, 70.1 years) with upper gastrointestinal neoplasms scheduled for endoscopic submucosal dissection (ESD) using conscious sedation with CO(2) insufflation, and EtCO(2) and PtCO(2) were simultaneously measured by each capnometer. Patient status was evaluated before ESD by the American Society of Anesthesiologists (ASA) physical status classification system, and eight patients were judged as class 1, nine patients as class 2, and three patients as class 3. The exclusion criteria ruled out patients with chronic obstructive pulmonary disease or ASA class 4 or 5 physical status. The correlation between EtCO(2) and PtCO(2) values and the availability of EtCO(2) capnography were investigated. RESULTS: The mean EtCO(2) value during ESD was 34.7 ± 4.5 mmHg, and the mean PtCO(2) value was 51.6 ± 2.4 mmHg. There was a statistically significant correlation between EtCO(2) and PtCO(2) (r = 0.331; P = 0.002). Hypoxic events (<90% oxygen saturation [SpO(2)]) caused by decreased respiratory rate occurred for 12 patients. In 10 (83%) of 12 events, a significant reduction in EtCO(2) was seen before the decrease in SpO(2). CONCLUSIONS: The EtCO(2) values correlated with the PtCO(2) values, and the respiratory monitoring methods allowed earlier detection of hypoxia during ESD with conscious sedation than transcutaneous monitoring. The EtCO(2) capnometer was considered to be available for the ESD procedure with the patient under conscious sedation using CO(2) insufflation.