Yoriaki Komeda

A comparison of the resection rate for cold and hot snare polypectomy for 4–9 mm colorectal polyps: a multicentre randomised controlled trial (CRESCENT study)

Objective To investigate the success rate of cold snare polypectomy (CSP) for complete resection of 4–9 mm colorectal adenomatous polyps compared with that of hot snare polypectomy (HSP). Design A prospective, multicentre, randomised controlled, parallel, non-inferiority trial conducted in 12 Japanese endoscopy units. Endoscopically diagnosed sessile adenomatous polyps, 4–9 mm in size, were randomly assigned to the CSP or HSP group. After complete removal of the polyp using the allocated technique, biopsy specimens from the resection margin after polypectomy were obtained. The primary endpoint was the complete resection rate, defined as no evidence of adenomatous tissue in the biopsied specimens, among all pathologically confirmed adenomatous polyps. Results A total of 796 eligible polyps were detected in 538 of 912 patients screened for eligibility between September 2015 and August 2016. The complete resection rate for CSP was 98.2% compared with 97.4% for HSP. The non-inferiority of CSP for complete resection compared with HSP was confirmed by the +0.8% (90% CI −1.0 to 2.7) complete resection rate (non-inferiority p<0.0001). Postoperative bleeding requiring endoscopic haemostasis occurred only in the HSP group (0.5%, 2 of 402 polyps). Conclusions The complete resection rate for CSP is not inferior to that for HSP. CSP can be one of the standard techniques for 4–9 mm colorectal polyps. (Study registration: UMIN000018328)

Removal of diminutive colorectal polyps: A prospective randomized clinical trial between cold snare polypectomy and hot forceps biopsy

AIM To compare the efficacy and safety of cold snare polypectomy (CSP) and hot forceps biopsy (HFB) for diminutive colorectal polyps. METHODS This prospective, randomized single-center clinical trial included consecutive patients ≥ 20 years of age with diminutive colorectal polyps 3-5 mm from December 2014 to October 2015. The primary outcome measures were en-bloc resection (endoscopic evaluation) and complete resection rates (pathological evaluation). The secondary outcome measures were the immediate bleeding or immediate perforation rate after polypectomy, delayed bleeding or delayed perforation rate after polypectomy, use of clipping for bleeding or perforation, and polyp retrieval rate. Prophylactic clipping after polyp removal wasn’t routinely performed. RESULTS Two hundred eight patients were randomized into the CSP (102), HFB (106) and 283 polyps were evaluated (CSP: 148, HFB: 135). The en-bloc resection rate was significantly higher with CSP than with HFB [99.3% (147/148) vs 80.0% (108/135), P < 0.0001]. The complete resection rate was significantly higher with CSP than with HFB [80.4% (119/148) vs 47.4% (64/135), P < 0.0001]. The immediate bleeding rate was similar between the groups [8.6% (13/148) vs 8.1% (11/135), P = 1.000], and endoscopic hemostasis with hemoclips was successful in all cases. No cases of perforation or delayed bleeding occurred. The rate of severe tissue injury to the pathological specimen was higher HFB than CSP [52.6% (71/135) vs 1.3% (2/148), P < 0.0001]. Polyp retrieval failure was encountered CSP (7), HFB (2). CONCLUSION CSP is more effective than HFB for resecting diminutive polyps. Further long-term follow-up study is required.

Outcome of Combination Therapy with Sofosbuvir and Ledipasvir for Chronic Type C Liver Disease

Introduction: Recently, the treatment of chronic hepatitis C has markedly advanced. A phase III clinical study of combination therapy with sofosbuvir (SOF) and ledipasvir (LDV) was conducted in Japan, and the additive therapeutic effects were reported. In this study, we report the results of treatment in our hospital. Methods: Of 147 patients with chronic type C liver disease who had consulted our hospital since September 2015 and received SOF/LDV therapy, in 91 subjects a sustained virological response of 12 weeks (SVR12) could be evaluated. Results: In all 91 patients, end treatment response was achieved. Subsequently, recrudescence was noted in 1 before the completion of treatment (week 12); an SVR12 was achieved in 90 patients (99%). The following adverse reactions were observed in 3 patients (3.3%): bradycardia, paroxysmal atrial fibrillation, and heart failure with QT prolongation, which were associated with heart disease. Conclusion: A favorable SVR was achieved by SOF/LDV therapy even in elderly patients, those with liver cirrhosis, or those having undergone radical treatment of liver cancer. Furthermore, a high tolerance was demonstrated, but adverse reactions associated with the heart may appear in patients with heart disease as an underlying disease; strict management during treatment is necessary.

Clinical Factors Predicting the Effect of Tolvaptan for Refractory Ascites in Patients with Decompensated Liver Cirrhosis.

Objective: Refractory ascites reduces the quality of life of liver cirrhosis patients. Albumin preparation and diuretics, such as furosemide, have been used to treat refractory ascites, but the effect was poor in many patients. In this study, we analyzed patients treated with tolvaptan (TLV) at our hospital and investigated predictors of the effect. Methods: The subjects were 70 patients for whom TLV was introduced to treat refractory ascites who could be analyzed between November 2013 and March 2015 at our hospital. Patient background before initiation of oral TLV treatment, the dose of diuretics, and each item of biochemical tests of blood and urine were investigated, and factors correlated with the treatment effect were analyzed. An increase of ≥1,000 ml in the daily urine volume from the day before oral treatment or a decrease of ≥1 kg in the body weight within 7 days as an early effect was observed in 33 patients and not observed in 37 patients. TLV treatment was continued for 60 days or longer in 12 of the 37 patients in whom no early effect was observed, and the presence or absence of a delayed effect and predictors of the effect were investigated. A decrease in ascites on abdominal CT with improvement of subjective symptoms at 60 days was defined as a delayed effect. Results: When early predictors of the effect were investigated by univariate analysis, serum blood urea nitrogen (BUN) and serum creatinine (Cr) were significantly higher in the non-responder group (BUN: p = 0.03, Cr: p = 0.04), but no factor independently associated with the treatment effect was extracted on multivariate analysis. The delayed effect was noted in 4 (33.3%) of the 12 patients, but no predictor of the effect before treatment was identified. However, reactions, such as an increase in serum Na and reduction of urinary osmotic pressure, were observed early after TLV administration in some patients in whom the delayed effect was observed. Conclusions: The diuretic effect of TLV may decrease in renal hypofunction patients. Since the delayed effect was noted in a specific ratio of patients, continuation of TLV administration is an option even though the early treatment effect is poor unless ascites aggravates or adverse effects develop.

Chronic Fibro-Inflammatory Responses in Autoimmune Pancreatitis Depend on IFN-α and IL-33 Produced by Plasmacytoid Dendritic Cells

In previous studies, we found that human IgG4-related autoimmune pancreatitis (AIP) and murine AIP are driven by activation of plasmacytoid dendritic cells (pDCs) producing IFN-α. In the present studies we examined additional roles of pDC-related mechanisms in AIP pathogenesis, particularly those responsible for induction of fibrosis. We found that in murine AIP (MRL/Mp mice treated with polyinosinic-polycytidylic acid) not only the pancreatic infiltration of immune cells but also the development of fibrosis were markedly reduced by the depletion of pDCs or blockade of type I IFN signaling; moreover, such treatment was accompanied by a marked reduction of pancreatic expression of IL-33. Conversely, polyinosinic-polycytidylic acid–induced inflamed pancreatic tissue in murine AIP exhibited increased expression of type I IFNs and IL-33 (and downstream IL-33 cytokines such as IL-13 and TGF-β1). pDCs stimulated by type I IFN were the source of the IL-33 because purified populations of these cells isolated from the inflamed pancreas produced a large amount of IL-33 upon activation by TLR9 ligands, and such production was abrogated by the neutralization of type I IFN. The role of IL-33 in murine AIP pathogenesis was surprisingly important because blockade of IL-33 signaling by anti-ST2 Ab attenuated both pancreatic inflammation and accompanying fibrosis. Finally, whereas patients with both conventional pancreatitis and IgG4-related AIP exhibited increased numbers of acinar cells expressing IL-33, only the latter also exhibited pDCs producing this cytokine. These data thus suggest that pDCs producing IFN-α and IL-33 play a pivotal role in the chronic fibro-inflammatory responses underlying murine AIP and human IgG4-related AIP.

Comparative Study of Clarithromycin- versus Metronidazole-Based Triple Therapy as First-Line Eradication for Helicobacter pylori

Introduction: Clarithromycin (CAM)-based triple therapy comprising proton pump inhibitors and amoxicillin is administered as first-line eradication treatment against Helicobacter pylori infection. However, the eradication rate achieved with CAM-based triple therapy has decreased to <80% owing to the emergence of CAM-resistant strains. This prospective randomized study aimed to compare the efficacy of CAM-based and metronidazole (MNZ)-based triple therapy in terms of H. pylori eradication. Methods:H. pylori-positive patients were treated with CAM-based triple therapy comprising esomeprazole and amoxicillin (EAC group) or with MNZ-based triple therapy comprising esomeprazole and amoxicillin (EAM group). Results:H. pylori eradication rates achieved in the intention-to-treat (ITT) and per protocol (PP) analyses were 70.6 and 72.7%, respectively, in the EAC group. Eradication rates obtained via ITT and PP analyses were 91.7 and 94.3%, respectively, in the EAM group. In the EAC group, eradication rates were significantly lower in patients harboring CAM-resistant strains than in those harboring CAM-sensitive strains. In contrast, eradication rates were comparable between patients harboring CAM-resistant strains and those harboring CAM-sensitive strains in the EAM group. Conclusion: MNZ-based triple therapy consisting of esomeprazole and amoxicillin is superior to CAM-based triple therapy containing esomeprazole and amoxicillin as first-line eradication treatment against H. pylori.

Computer-Aided Diagnosis Based on Convolutional Neural Network System for Colorectal Polyp Classification: Preliminary Experience

Background and Aim: Computer-aided diagnosis (CAD) is becoming a next-generation tool for the diagnosis of human disease. CAD for colon polyps has been suggested as a particularly useful tool for trainee colonoscopists, as the use of a CAD system avoids the complications associated with endoscopic resections. In addition to conventional CAD, a convolutional neural network (CNN) system utilizing artificial intelligence (AI) has been developing rapidly over the past 5 years. We attempted to generate a unique CNN-CAD system with an AI function that studied endoscopic images extracted from movies obtained with colonoscopes used in routine examinations. Here, we report our preliminary results of this novel CNN-CAD system for the diagnosis of colon polyps. Methods: A total of 1,200 images from cases of colonoscopy performed between January 2010 and December 2016 at Kindai University Hospital were used. These images were extracted from the video of actual endoscopic examinations. Additional video images from 10 cases of unlearned processes were retrospectively assessed in a pilot study. They were simply diagnosed as either an adenomatous or nonadenomatous polyp. Results: The number of images used by AI to learn to distinguish adenomatous from nonadenomatous was 1,200:600. These images were extracted from the videos of actual endoscopic examinations. The size of each image was adjusted to 256 × 256 pixels. A 10-hold cross-validation was carried out. The accuracy of the 10-hold cross-validation is 0.751, where the accuracy is the ratio of the number of correct answers over the number of all the answers produced by the CNN. The decisions by the CNN were correct in 7 of 10 cases. Conclusion: A CNN-CAD system using routine colonoscopy might be useful for the rapid diagnosis of colorectal polyp classification. Further prospective studies in an in vivo setting are required to confirm the effectiveness of a CNN-CAD system in routine colonoscopy.

Outcome of Asunaprevir/Daclatasvir Combination Therapy for Chronic Liver Disease Type C

Objective: Treatment for chronic hepatitis C has recently developed in a very rapid manner. In Japan, in September 2014, IFN-free asunaprevir (ASV) and daclatasvir (DCV) became available for combination therapy. We report the treatment outcomes achieved at our hospital using this combination therapy. Methods: Sustained virological response (SVR) 24 could be evaluated in 120 of 125 patients with chronic liver disease type C who visited our hospital and were treated with ASV/DCV after September 2014, and these patients were analyzed. Results: SVR24 was achieved in 106 patients (88%). End-of-treatment response was not achieved in 10 patients (8.3%). Five of them carried multiple-resistant NS3/4A or NS5A region, and administration was discontinued early in 4 patients due to adverse effects. After ASV/DCV treatment, hepatocellular carcinoma (HCC) developed in 2 patients (1.7%) and recurred in 5 (4.2%). Conclusions: ASV/DCV treatment achieved favorable SVR in elderly and hepatic cirrhosis patients and patients in whom HCC was cured. However, an increase in the incidence of HCC development in patients who markedly respond to direct-acting antivirals treatment is expected and surveillance of HCC becomes more important.

Clinical Significance of Bmi1 Expression in Inflammatory Bowel Disease

Background: Although the stem cell marker Bmi1 is overexpressed in many malignancies, its role in inflammation-associated cancer is unclear. Colitis-associated cancer (CAC) is caused by chronic intestinal inflammation and often results from refractory inflammatory bowel disease (IBD). Methods: To assess the involvement of Bmi1 in the development of CAC, we analyzed the gene expression of colon tissues collected from 111 patients with IBD and CAC. Results: In the colonic mucosa of patients with ulcerative colitis, the expression of Bmi1 correlated significantly with the expression of inflammatory cytokines such as IL-6, IL-17, IL-23, and tumor necrosis factor α (TNF-α). In the colonic mucosa of patients with Crohns disease, the expression of Bmi1 correlated significantly with the expression of TNF-α and IL-23. The expression of Bmi1 was enhanced in the colonic mucosae of refractory IBD, suggesting that Bmi1 expression might be related to increased cancer risk. In addition, patients with high Bmi1 expression showed significantly lower response rates upon subsequent anti-TNF-α therapy as compared to patients with low Bmi1 expression. In human CAC specimens, the expression of Bmi1 was upregulated in nontumor tissues as well as tumors. Conclusions: Bmi1 expression is related to a refractory clinical course of IBD and upregulated in refractory IBD and CAC. Measurement of Bmi1 expression is a promising approach for the advanced treatment and personalized management of IBD patients.

The oncoprotein gankyrin promotes the development of colitis-associated cancer through activation of STAT3

Although long-standing colonic inflammation due to refractory inflammatory bowel disease (IBD) promotes the development of colitis-associated cancer (CAC), the molecular mechanisms accounting for the development of CAC remains largely unknown. In this study, we investigated the role of gankyrin in the development of CAC since gankyrin is overexpressed in sporadic colorectal cancers. We analyzed gene expression of colon tissues obtained from 344 patients with IBD and CAC and found that expression of gankyrin was much higher in colonic mucosa of patients with refractory IBD than in those with IBD in remission. Expression of gankyrin was upregulated in inflammatory cells as well as tumor cells in colonic mucosa of patients with CAC. Over-expressing studies utilizing tagged ganlyrin-cDNA identified physical interaction between ganlyrin and Src homology 2-containing protein tyrosine phosphatase-1 (SHP-1). Importantly, the interaction between ganlyrin and SHP-1 leads to inhibition of STAT3 activation and to enhancement of TNF-α and IL-17 in inflammatory cells. To further address the role of gankyrin in the development of CAC, we created mice with intestinal epithelial cell-specific gankyrin ablation (Vil-Cre;Gankyrinf/f) and deletion of gankyrin in myeloid and epithelial cells (Mx1-Cre;Gankyrinf/f). Gankyrin deficiency in myeloid cells, but not in epithelial cells, reduced the activity of mitogen activated protein kinase and the expression of stem cell markers, leading to attenuated tumorigenic potential. These findings provide important insights into the pathogenesis of CAC and suggest that gankyrin is a promising target for developing therapeutic and preventive strategies against CAC.