Ken Kawakami

Comparative study of conventional colonoscopy and pan-colonic narrow-band imaging system in the detection of neoplastic colonic polyps: a randomized, controlled trial.

Background. Detection and removal of adenomas by colonoscopy is an important means for preventing cancer; however, small adenomas may be missed during colonoscopy. The narrow-band imaging (NBI) system clearly enhances the microvasculature in neoplastic lesions, making it appear as a dark complex. Therefore, the NBI system may improve the detection of colonic neoplasias. However, no randomized, controlled trials have evaluated the efficacy of a pan-colonic NBI system in adenoma detection. We conducted a randomized, controlled trial to determine the efficacy of the pancolonic NBI system in adenoma detection. Methods. Two hundred forty-three patients were randomized, 121 to conventional colonoscopy and 122 to pan-colonic NBI system. Demographics, indication for colonoscopy, and quality of preparation were similar between groups. Results. Extubation time was not significantly different between the conventional colonoscopy and pan-colonic NBI system. The proportions of patients with at least one adenoma and those with multiple adenomas were not significantly different between groups. However, the pan-colonic NBI system significantly increased the total number of adenomas detected (P < 0.05) and the number of diminutive (<5 mm) adenomas detected (P < 0.05). The pan-colonic NBI system allowed detection of more diminutive adenomas in the distal colon than did conventional colonoscopy (P < 0.01), and more patients in the NBI group had at least one diminutive adenoma than in the control group (P < 0.05). Conclusions. The pan-colonic NBI system improves the total number of adenomas detected, including significantly more diminutive adenomas, without prolongation of extubation time. These results indicate that routine use of the NBI system for surveillance of diminutive adenomas may be recommended.

Utility and problems of endoscopic submucosal dissection for early gastric cancer in elderly patients.

Background and Aim:  Endoscopic submucosal dissection (ESD) is reported to be a safe and reliable procedure for the elderly, but these reports could have already had a bias at the time ESD was performed. However, the reports have not clearly stated the criteria of indications. In the present study, we retrospectively elucidated the usefulness and problems of ESD for early gastric cancer in elderly patients (≥ 65 years) in comparison with non‐elderly patients.

Simvastatin Attenuates Intestinal Fibrosis Independent of the Anti-Inflammatory Effect by Promoting Fibroblast/Myofibroblast Apoptosis in the Regeneration/Healing Process from TNBS-Induced Colitis

BackgroundIntestinal deformity and stenosis are induced by fibrosis during the process healing of intestinal chronic inflammation in inflammatory bowel disease (IBD). Potent anti-inflammatory treatment of patients with Crohn’s disease (CD) may induce fibrous stenosis, and this is often difficult to treat in clinical practice. Therefore, it is necessary to develop a treatment strategy that concomitantly exhibits repair/regenerative and anti-fibrotic effects, in addition to the current anti-inflammatory effect, for the treatment of inflammatory bowel diseases. However, the relationship between the course of inflammatory activity and the healing process and fibrogenesis has not been elucidated; although the complex involvement of various factors in the mechanism of biological fibrosis has been investigated. Simvastatin (SIMV), an HMG-CoA reductase inhibitor, exhibits anti-inflammatory and anti-fibrotic effects. The current study established a model of the regeneration/healing process from TNBS-induced colitis and investigated the anti-inflammatory and anti-fibrotic effects of SIMV.Subjects and MethodsFour groups of TNBS-induced colitis model were prepared using male SJL/J mice: A: Normal control group, B: control group, and C and D: treatment groups. The mucosal healing process was classified into three phases (an early phase: inflammation period, a mid-phase: regeneration promoting period, and a late phase: regeneration-converging period), and inflammation, the expression of fibrosis-related growth factors, and induction of apoptosis of fibrosis-related cells were compared in each period.Results(1) The clinical findings showed that SIMV showed anti-inflammatory effects with body weight gain and improvement of epithelial injury in the late phase. Histological (macroscopic/microscopic) improvement was noted in the mid- and late phases. The inflammatory cytokine (TNF-α) level significantly decreased in the mid- and late phases in the high-dose treatment group. (2) SIMV also had anti-fibrotic effects characterized by a dose-dependent decrease in the level of a fibrosis-related growth factor (CTGF) in the early and mid-phases, irrespective of inflammation or changes in the TGF-β1 level. Dose-dependent induction of apoptosis was noted in both fibroblasts and myofibroblasts from a relatively early stage.ConclusionsThe results suggested that SIMV induces anti-fibrotic activity that is not directly involved in the anti-inflammatory effect from a relatively early stage the healing process of TNBS-induced colitis.

Preventive effect of irsogladine or omeprazole on non-steroidal anti-inflammatory drug-induced esophagitis, peptic ulcers, and small intestinal lesions in humans, a prospective randomized controlled study

BackgroundProton-pump inhibitors such as omeprazole are a standard treatment to prevent non-steroidal anti-inflammatory drug-induced upper gastrointestinal mucosal injuries. However, it is unclear which drugs may protect against all NSAID-induced digestive-tract injuries. Here, we compare the efficacy of the gastromucoprotective drug irsogladine with omeprazole in preventing NSAID-induced esophagitis, peptic ulcers, and small-intestinal mucosal injury in healthy subjects.MethodsThirty-two healthy volunteers were assigned to an irsogladine group (Group I; n = 16) receiving diclofenac sodium 75 mg and irsogladine 4 mg daily for 14 days, or an omeprazole group (Group O; n = 16) receiving diclofenac sodium 75 mg and omeprazole 10 mg daily for 14 days. Esophagitis and peptic ulcers were evaluated by esophagogastroduodenoscopy and small-intestinal injuries by capsule endoscopy, fecal calprotectin, and fecal occult blood before and after treatment.ResultsThere was no significant difference between Group I and Group O with respect to the change in lesion score in the esophagus, stomach, and duodenum before and after treatment.NSAID treatment significantly increased the number of small intestinal mucosal breaks per subject by capsule endoscopic evaluation, from a basal level of 0.1 ± 0.3 up to 1.9 ± 2.0 lesions in Group O (p = 0.0002). In contrast, there were no significant changes in the mean number of mucosal breaks before and after co-treatment in Group I (0.3 ± 0.8 to 0.5 ± 0.7, p = 0.62), and the between-group difference was significant (p = 0.0040). Fecal calprotectin concentration, when the concentration before treatment was defined as 1, was significantly increased both in Group O (from 1.0 ± 0.0 to 18.1 ± 37.1, p = 0.0002) and Group I (from 1.0 ± 0.0 to 6.0 ± 11.1, p = 0.0280); the degree of increase in Group O was significantly higher compared with that in Group I (p<0.05). In addition, fecal occult blood levels increased significantly in Group O (p = 0.0018), but there was no change in Group I (p = 1.0), and the between-group difference was significant (p = 0.0031).ConclusionIrsogladine protected against NSAID-induced mucosal injuries throughout the gastrointestinal tract, from esophagus to small intestine, significantly better than omeprazole.Trial registrationThis study was registered in the UMIN Clinical Trials Registry (Registry ID number; UMIN000008114)

Proliferative effects of γ-aminobutyric acid on the gastric cancer cell line are associated with extracellular signal-regulated kinase 1/2 activation

Background and Aim:  γ‐Aminobutyric acid (GABA) is the principal inhibitory neurotransmitter in the adult mammalian brain. However, GABA is found not only in peripheral neuronal tissue, but also in many peripheral non‐neuronal tissues, and is thought to have important physiological functions in addition to neurotransmission. We previously reported that GABA participates in chondrocyte proliferation. In the present study, we investigated the effects of GABA on the proliferation of a gastric cancer cell line, KATO III.

Effects of oral tacrolimus as a rapid induction therapy in ulcerative colitis.

AIM To determine the efficacy and safety of rapid induction therapy with oral tacrolimus without a meal in steroid-refractory ulcerative colitis (UC) patients. METHODS This was a prospective, multicenter, observational study. Between May 2010 and August 2012, 49 steroid-refractory UC patients (55 flare-ups) were consecutively enrolled. All patients were treated with oral tacrolimus without a meal at an initial dose of 0.1 mg/kg per day. The dose was adjusted to maintain trough whole-blood levels of 10-15 ng/mL for the first 2 wk. Induction of remission at 2 and 4 wk after tacrolimus treatment initiation was evaluated using Lichtigers clinical activity index (CAI). RESULTS The mean CAI was 12.6 ± 3.6 at onset. Within the first 7 d, 93.5% of patients maintained high trough levels (10-15 ng/mL). The CAI significantly decreased beginning 2 d after treatment initiation. At 2 wk, 73.1% of patients experienced clinical responses. After tacrolimus initiation, 31.4% and 75.6% of patients achieved clinical remission at 2 and 4 wk, respectively. Treatment was well tolerated. CONCLUSION Rapid induction therapy with oral tacrolimus shortened the time to achievement of appropriate trough levels and demonstrated a high remission rate 28 d after treatment initiation. Rapid induction therapy with oral tacrolimus appears to be a useful therapy for the treatment of refractory UC.

Clinical effects of adalimumab treatment with concomitant azathioprine in Japanese Crohn's disease patients.

AIM To assess adalimumabs efficacy with concomitant azathioprine (AZA) for induction and maintenance of clinical remission in Japanese Crohns disease (CD) patients. METHODS This retrospective, observational, single-center study enrolled 28 consecutive CD patients treated with adalimumab (ADA). Mean age and mean disease duration were 38.1 ± 11.8 years and 11.8 ± 10.1 years, respectively. The baseline mean Crohns disease activity index (CDAI) and C-reactive protein were 177.8 ± 82.0 and 0.70 ± 0.83 mg/dL, respectively. Twelve of these patients also received a concomitant stable dose of AZA. ADA was subcutaneously administered: 160 mg at week 0, 80 mg at week 2, followed by 40 mg every other week. Clinical response and remission rates were assessed via CDAI and C-reactive protein for 24 wk. RESULTS The mean CDAI at weeks 2, 4, 8, and 24 was 124.4, 120.2, 123.6, and 135.1, respectively. The CDAI was significantly decreased at weeks 2 and 4 with ADA and was significantly suppressed at 24 wk with ADA/AZA. Overall clinical remission rates at weeks 4 and 24 were 66.7% and 63.2%, respectively. Although no statistically significant difference in C-reactive protein was demonstrated, ADA with AZA resulted in a greater statistically significant improvement in CDAI at 24 wk, compared to ADA alone. CONCLUSION Scheduled ADA with concomitant AZA may be more effective for clinical remission achievement at 24 wk in Japanese Crohns disease patients.

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)

Primary CD56+ NK/T-cell lymphoma of the rectum accompanied with refractory ulcerative colitis.

A case of primary NK/T-cell lymphoma of the rectum accompanied with ulcerative colitis (UC) in a 73-year-old man is reported. He had a 6-year history of repeated admission to our hospital for UC. Total colonoscopy performed 4 months after resolution of refractory UC complicated by cytomegalovirus colitis showed a markedly submucosal tumor in the rectum, which was histologically diagnosed as malignant lymphoma. The findings of computed tomography of the chest and abdomen, gallium scintigraphy, abdominal ultrasonography, and upper gastrointestinal endoscopy showed no abnormal lesions. Therefore, based on a diagnosis of localized rectal lymphoma with UC, proctocolectomy was performed. The resected specimen showed three submucosal tumors in the rectum with local nodal involvement. Histologically, the tumors were characterized by diffusely infiltrating sheets of large atypical lymphoid cells, which were negative for CD4, CD8, and CD20 but were positive for CD56, CD3, and granzyme B. The presence of Epstein-Barr virus (EBV) infection in neoplastic cells was shown by in situ hybridization for EBV-encoded early small RNA1 (EBER-1). Based on these findings, the patient was diagnosed with primary CD56+ NK/T-cell lymphoma of the rectum (stage IIE). This is the first case report of primary rectal NK/T-cell lymphoma accompanied with UC.

The dipeptidyl peptidase-4 inhibitor sitagliptin suppresses mouse colon tumorigenesis in type 2 diabetic mice

Patients with type 2 diabetes mellitus are known to have an increased risk of colorectal neoplasia. Dipeptidyl peptidase-4 (DPP-4) inhibitors have been used as a new therapeutic tool for type 2 diabetes. Since the substrates for DPP-4 include intestinotrophic hormones and chemokines such as GLP-2 and stromal cell-derived factor-1 (SDF-1), which are associated with tumor progression, DPP-4 inhibitors may increase the risk of colorectal tumors. However, the influence of DPP-4 inhibitors on colorectal neoplasia in patients with type 2 diabetes remains unknown. In the present study, we show that long-term administration of a DPP-4 inhibitor, sitagliptin (STG), suppressed colon carcinogenesis in leptin-deficient (ob/ob) C57BL/6J mice. Colonic mucosal concentrations of glucagon‑like peptide-1 (GLP-1) and GLP-2 were significantly elevated in the ob/ob mice. However, mucosal GLP concentrations and the plasma level of SDF-1 were not affected by the administration of STG. Real‑time PCR analysis revealed that colonic mucosal IL-6 mRNA expression, which was significantly upregulated in the ob/ob mice, was significantly suppressed by the long-term administration of STG. These results suggest that a DPP-4 inhibitor may suppress colon carcinogenesis in mice with type 2 diabetes in a GLP-independent manner. Since DPP-4 has multiple biological functions, further studies analyzing other factors related to colon carcinogenesis are needed.