坂本 博次

Gastric mucosal changes associated with long-term potassium-competitive acid blocker and proton pump inhibitor (PPI) therapy may raise concern. In contrast to that for PPIs, the evidence concerning the safety of long-term potassium-competitive acid blocker use is scant. Vonoprazan (VPZ) is a representative potassium-competitive acid blocker released in Japan in 2015. In order to shed some comparative light regarding the outcomes of gastric mucosal lesions associated with a long-term acid blockade, we have reviewed six representative gastric mucosal lesions: fundic gland polyps, gastric hyperplastic polyps, multiple white and flat elevated lesions, cobblestone-like gastric mucosal changes, gastric black spots, and stardust gastric mucosal changes. For these mucosal lesions, we have evaluated the association with the type of acid blockade, patient gender, Helicobacter pylori infection status, the degree of gastric atrophy, and serum gastrin levels. There is no concrete evidence to support a significant relationship between VPZ/PPI use and the development of neuroendocrine tumors. Current data also shows that the risk of gastric mucosal changes is similar for long-term VPZ and PPI use. Serum hypergastrinemia is not correlated with the development of some gastric mucosal lesions. Therefore, serum gastrin level is unhelpful for risk estimation and for decision-making relating to the cessation of these drugs in routine clinical practice. Given the confounding potential neoplastic risk relating to H. pylori infection, this should be eradicated before VPZ/PPI therapy is commenced. The evidence to date does not support the cessation of clinically appropriate VPZ/PPI therapy solely because of the presence of these associated gastric mucosal lesions.

BACKGROUND AND AIM: Peutz-Jeghers syndrome (PJS) and juvenile polyposis syndrome (JPS) are autosomal dominant diseases associated with high cancer risk. In Japan, knowledge about the prevalence and incidence of PJS and JPS is lacking despite being crucial for providing appropriate medical support. We aimed to determine the prevalence and incidence of these diseases. METHODS: In 2022, a nationwide questionnaire survey was conducted to determine the number of patients with PJS or JPS by sex and the number of newly confirmed cases from 2019 to 2021. The target facilities included gastroenterology, pediatrics, and pediatric surgery departments, which were stratified into seven classes on the basis of the total number of beds. We randomly selected target facilities using different extraction rates in each class, resulting in 1748/2912 facilities (extraction rate: 60%) as the final sample. We calculated the estimated number of patients using the response and extraction rates. RESULTS: A total of 1077 facilities responded to the survey. The estimated numbers of patients with PJS and JPS were 701 (95% confidence interval [CI]: 581-820) and 188 (95% CI: 147-230), respectively. The 3-year period prevalences of PJS and JPS were 0.6/100000 and 0.15/100000, whereas the incidences in 2021 were 0.07/100000 and 0.02/100000, respectively. Male patients constituted 53.5% and 59.6% in the PJS and JPS groups, respectively. CONCLUSIONS: We determined the prevalence and incidence of PJS and JPS in Japan for the first time. Further research is needed to obtain more detailed information, including the clinical differences and outcomes in Japan.

Ulcerative colitis (UC), a subtype of inflammatory bowel disease, occasionally manifests with extraintestinal manifestations. We present a 51-year-old male with refractory UC and immune thrombocytopenia (ITP) resistant to conventional treatments. The introduction of biologics, ustekinumab or adalimumab, resulted in clinical remission of colitis and improvements in platelet count. This case underscores the efficacy of biologics in managing refractory UC associated with ITP, emphasizing their potential to control intestinal inflammation and address concurrent thrombocytopenia, potentially avoiding surgical intervention.

Hydroxycarbamide, an antimetabolic agent used to treat myeloproliferative disorders, causes side effects, including myelosuppression, skin ulcers, and oral mucositis. Gastrointestinal ulcers are uncommon, and esophageal ulcers have not been previously reported. We present the case of a 74-year-old woman who developed esophageal and ileal ulcers after hydroxycarbamide treatment. Our case and previous reports suggest that hydroxycarbamide can cause ulcers throughout the gastrointestinal tract, which can improve rapidly after discontinuing medication. When new signs and symptoms occur, drug-induced etiologies should be considered as a potential cause. Timely diagnostic treatment with discontinuation of medication is crucial in such cases.

BACKGROUND: Gastroesophageal reflux disease (GERD) symptoms frequently recur after cessation of acid blockers. The presence of a hiatal hernia may worsen GERD symptoms and increase the risk of esophageal malignancy. The aim of this study is to clarify the timing and predictors for recurrence of GERD symptoms after cessation of vonoprazan (VPZ) therapy. METHODS: A retrospective observational study involved 86 patients who underwent cessation of VPZ therapy for symptomatic GERD. Collated data from medical record review included the endoscopic findings and Izumo scale score. RESULTS: The mean duration of continuous VPZ therapy before cessation was 7.9 months. GERD symptoms requiring the resumption of VPZ therapy recurred in 66 of 86 patients (77%). Kaplan-Meier analysis showed that overall recurrence-free rates at 6 months, one and two years after VPZ cessation were 44%, 32% and 23%, respectively. Alcohol use, the presence of a hiatal hernia and long-term therapy for more than six months were identified as significant positive predictors for symptomatic recurrence. Notably, hiatal hernia had the highest hazard ratio in both univariate and multivariate analyses. The recurrence-free rate in patients with a hiatal hernia was much lower at 6 months than in patients without a hiatal hernia (15% and 51%, respectively p = 0.002). After the symptomatic recurrence, GERD symptoms improved significantly after one-month VPZ therapy. CONCLUSION: The rate of symptomatic recurrence after VPZ cessation in patients with GERD is considerable. Cessation of acid suppression therapy should be cautious in patients with both a hiatal hernia and GERD.

Background and study aims Small-bowel polyps in patients with Peutz-Jeghers syndrome (PJS) are sometimes difficult to reach using double-balloon enteroscopy (DBE). However, they can induce intussusception, especially when ≧15 mm. This study aimed to review the outcomes of patients with such polyps. Patients and methods All patients with PJS with small-bowel polyps that bidirectional DBE failed to reach and were ≧5 mm as shown by DBE enterography at our institution from May 2006 to April 2022 were retrospectively evaluated. The endpoint was the earliest occurrence of symptomatic intussusception induced by the polyp, endoscopic removal by repeat DBE or intraoperative endoscopy, or the last medical record describing the patient's condition. Results This study included 27 polyps in 13 patients. All patients had extraluminal adhesions. None developed symptomatic intussusception, eight patients underwent endoscopic removal at repeat DBE without surgery, two patients underwent removal with intraoperative endoscopy, two patients were observed without polyp removal, and one patient had a polyp removed at repeat DBE and three unreachable polyps remained. Repeat DBE without surgery was able to remove 14 polyps (52%). Polyps ≧15 mm included 11 lesions in eight patients and were observed for a median of 14 months without symptomatic intussusception. Conclusions The difficult-to-reach polyps may have a low risk of immediate symptomatic intussusception, possibly due to limited bowel mobility by extraluminal adhesions, and the likelihood of reaching them at repeat DBE was substantial. Hence, repeat DBE 1 year later may be proper in such patients with PJS.

OBJECTIVES: Although the laser light is optically ideal for producing narrow-band light, it has not been used in some areas of the world. Endoscopic light sources using light-emitting diodes (LEDs) are used worldwide. The purpose of this study was to compare blue laser imaging (laser-BLI) and LED-blue light imaging (LED-BLI) for the characterization of colorectal polyps using the Japan narrow band imaging expert team (JNET) classification. METHODS: Colorectal lesions were prospectively examined using magnifying narrow-band light generated by a laser (laser-BLI) or LEDs (LED-BLI). Twelve endoscopists (six non-experts and six experts from three institutions) evaluated each still-magnified image of lesions using the JNET classification. RESULTS: Seven hundred and fifty-six images from 63 lesions were reviewed. The mean polyp size was 24.5 ± 13.4 mm. Histopathology included 13 serrated lesions and 50 neoplasms. The rate of agreement between laser-BLI and LED-BLI using the JNET classification was 92.5% (699/756). The weighted κ-statistic was 0.99. The percentages of "almost similar" comparing scores of surface patterns, vessel patterns, and brightness among all endoscopists were 95.4%, 95.9%, and 95.0%, respectively. CONCLUSIONS: This multicenter study demonstrates that the rate of agreement between laser-BLI and LED-BLI using the JNET Classification is very high. The surface patterns, vessel patterns, and brightness are almost similar.

BACKGROUND: Peutz-Jeghers syndrome (PJS) is a rare disease characterized by the presence of hamartomatous polyposis throughout the gastrointestinal tract, except for the esophagus, along with characteristic mucocutaneous pigmentation. It is caused by germline pathogenic variants of the STK11 gene, which exhibit an autosomal dominant mode of inheritance. Some patients with PJS develop gastrointestinal lesions in childhood and require continuous medical care until adulthood and sometimes have serious complications that significantly reduce their quality of life. Hamartomatous polyps in the small bowel may cause bleeding, intestinal obstruction, and intussusception. Novel diagnostic and therapeutic endoscopic procedures such as small-bowel capsule endoscopy and balloon-assisted enteroscopy have been developed in recent years. SUMMARY: Under these circumstances, there is growing concern about the management of PJS in Japan, and there are no practice guidelines available. To address this situation, the guideline committee was organized by the Research Group on Rare and Intractable Diseases granted by the Ministry of Health, Labour and Welfare with specialists from multiple academic societies. The present clinical guidelines explain the principles in the diagnosis and management of PJS together with four clinical questions and corresponding recommendations based on a careful review of the evidence and involved incorporating the concept of the Grading of Recommendations Assessment, Development and Evaluation system. KEY MESSAGES: Herein, we present the English version of the clinical practice guidelines of PJS to promote seamless implementation of accurate diagnosis and appropriate management of pediatric, adolescent, and adult patients with PJS.

BACKGROUND: Endoscopic balloon dilation (EBD) is an effective, minimally invasive treatment for Crohn's disease (CD) related intestinal strictures. However, restenosis frequently occurs and requires repetitive EBD or surgical resection. Since previous studies could not evaluate restenosis based on stricture diameter, factors affecting restenosis after EBD were unclear. This study aimed to identify these factors by precisely measuring the diameter of small intestinal strictures in patients with CD. METHODS: This single-center retrospective study enrolled patients with CD with de novo small intestinal strictures who underwent two double-balloon enteroscopy sessions (EBD and follow-up) between January 2016 and October 2021. Clinical and endoscopic data were obtained from electronic medical records. A calibrated small-caliber-tip transparent hood was used to precisely measure stricture diameters. Multivariate analysis was performed to identify factors associated with restenosis. RESULTS: Forty-eight patients (37 male) were analyzed. The total number of strictures detected decreased from 162 to 143. The mean diameter of all strictures and the narrowest stricture in each patient increased significantly from 8.6 to 9.8 mm and from 7.6 to 8.7 mm, respectively. Thirty-two (67%) patients developed endoscopic restenosis. Multivariate analysis showed that the presence of ulcers at the follow-up session was a risk factor for restenosis (odds ratio 9.4, p = 0.01). Patients with complete mucosal healing at both sessions (n = 21) showed significant improvement in the narrowest stricture (+1.7 mm, p = 0.001). CONCLUSIONS: Maintenance of complete mucosal healing is significantly associated with avoiding restenosis after EBD in CD-related small intestinal strictures.

BACKGROUND AND AIMS: Acid suppression improves dyspepsia symptoms but the efficacy of vonoprazan for functional dyspepsia remains unclear. The aim of this study is to evaluate the effectiveness of vonoprazan therapy for functional dyspepsia without heartburn. METHODS: Patients receiving vonoprazan 10 mg once daily or acotiamide 100 mg three times daily for more than one month were included and retrospectively reviewed. Functional dyspepsia was diagnosed based on the ROME IV criteria. Patients with heartburn were excluded. Eighty-five patients were divided into vonoprazan (n=48) and acotiamide (n=37) groups. RESULTS: There were no significant differences at baseline between the vonoprazan and acotiamide groups. The functional dyspepsia score significantly improved in both groups (p<0.001). The degree of score reduction (55% vs 59%, p=0.559) and the resolution rates (21% vs 30%, p=0.345) were similar. Epigastric pain and postprandial distress scores were significantly improved in both groups, and the degree of improvement of each score was similar. Constipation and diarrhea scores were significantly improved in both groups, and the degree of improvement similar. CONCLUSION: These preliminary results suggest that vonoprazan is effective for the treatment of functional dyspepsia without heartburn in the short-term, with results similar to acotiamide therapy.

Nonalcoholic fatty liver disease (NAFLD), a hepatic characteristic of metabolic syndrome, received significant attention in clinical settings. The multiple-hit theory is one of the proposed mechanisms of NAFLD, and gut dysbiosis is considered a hit. Thus, controlling gut microbiota is a potential target in the management of NAFLD, and probiotics can be used as a treatment agent for NAFLD. The current study aimed to investigate the efficacy of probiotics against nonalcoholic steatohepatitis in a hepatocyte-specific PTEN knockout mouse model that mimics the characteristics of human NAFLD. Probiotics were administered to male knockout mice for 8 or 40 weeks. Next, we assessed hepatic inflammation, fibrosis, carcinogenesis, and oxidative stress. Probiotics were found to reduce serum transaminase levels, NAFLD activity score, and the gene expression of pro-inflammatory cytokines. In addition, they decreased liver fibrosis grade, which was examined via Sirius red staining, gene expression of fibrotic markers, and hydroxyproline. Furthermore, probiotics suppressed the number of liver tumors, particular in HCC. Probiotics reduced oxidative stresses, including glutathione levels, and anti-oxidative stress marker, which may be an underlying mechanism for their beneficial effects. In conclusion, probiotics treatment had beneficial effects against NAFLD and carcinogenesis in hepatocyte-specific PTEN knockout mice.

BACKGROUND: Long-term acid suppression during vonoprazan therapy causes hypergastrinemia which may induce gastric mucosal changes such as fundic gland and hyperplastic polyps. The aim of this study is to clarify the long-term changes in serum gastrin levels and risk factors for hypergastrinemia. METHODS: From July 2016 to April 2020, 48 patients receiving vonoprazan 10 mg once daily for more than one year were reviewed. Serum gastrin level was evaluated by radioimmunoassay in a fasting condition (reference range 37-172 pg/ml). RESULTS: The baseline median gastrin level was 100 (range, 54-415) pg/ml. The gastrin level over 4 years was 700-1200 pg/ml, which plateaued at 1.5 years. Multivariate analysis revealed factors associated with gastrin levels 12 months after starting vonoprazan and identified severe gastric atrophy as a significant positive risk factor (p = .046). The gastrin level over 4 years in patients with severe gastric atrophy and no atrophy was approximately 900-1500 and 500-1000 pg/ml, respectively. Female gender was also identified as a positive factor, although it was not statistically significant (p = .087). The gastrin level over 4 years in females was approximately 900-1300 pg/ml, greater than in males (500-900 pg/ml). CONCLUSION: A continued increase in gastrin levels was not found during long-term vonoprazan therapy. Severe gastric atrophy is a significant risk factor for hypergastrinemia.

Endoscopic submucosal dissection can remove large superficial gastrointestinal lesions in en bloc. A detailed pathological evaluation of the resected specimen is required to assess the risk of recurrence after treatment. However, the current method of sectioning specimens to a thickness of a few millimeters does not provide information between the sections that are lost during the preparation. In this study, we have produced three-dimensional images of the entire dissected lesion for nine samples by using micro-CT imaging system. Although it was difficult to diagnose histological type on micro-CT images, it successfully evaluates the extent of the lesion and its surgical margins. Micro-CT images can depict sites that cannot be observed by the conventional pathological diagnostic process, suggesting that it may be useful to use in a complementary manner.

OBJECTIVES: In light emitting diode (LED) and LASER colonoscopy, linked color imaging (LCI) superiority to white light imaging (WLI) for polyp detection is shown separately. We analyzed the non-inferiority of LCI between LED and LASER colonoscopy and that of WLI. METHODS: We prospectively observed lesions with WLI and LCI using LED and LASER colonoscopy from January 2021 to August 2021. All images were evaluated randomly by 12 endoscopists (six non-experts and six experts in three institutions) using the polyp visibility score; 4 (excellent), 3 (good), 2 (fair) and 1 (poor). The comparison score (LED better/similar/LASER better) for redness and brightness was evaluated for WLI and LCI pictures of each lesion. RESULTS: Finally, 63 lesions were evaluated, and the mean polyp size was 24.5±13.4 mm. Histopathology revealed 13 serrated lesions and 50 adenomatous/cancerous lesions. The mean polyp visibility scores of LCI pictures were significantly higher than those of WLI in LED (3.35±0.85 vs. 3.08±0.91, p<0.001) and LASER (3.40±1.71 vs. 3.05±0.97, p<0.001) group, and the non-inferiority of LCI pictures between LED and LASER was significant (p<0.001). The comparison scores revealed that the evaluation of redness and brightness (LED better/similar/LASER better) were 26.8%/40.1%/33.1% and 43.5%/43.5%/13.0% for LCI pictures (p<0.001) and 20.6%/44.3%/35.1% and 60.3%/31.7%/8.0% for WLI pictures (p<0.001), respectively. CONCLUSIONS: The non-inferiority of polyp visibility with WLI and LCI in LED and LASER colonoscopy is shown. WLI and LCI of LED tended to be brighter and less reddish than those of LASER.

The safety of long-term proton pump inhibitor (PPI) and vonoprazan (VPZ) use is a relatively recent concern. Gastric mucosal redness was reported as a VPZ-associated lesion in a previous study. The aim of this study was to investigate the prevalence and risk factors for gastric mucosal redness. Between December 2020 and November 2021, 1,101 patients who underwent esophagogastroduodenoscopy were reviewed. The cohort was divided into four groups: Control (n=580), histamine-2 receptor antagonist (H2RA) (n=65), PPI (n=146) and VPZ groups (n=310). Gastric mucosal redness was present in 48/1,101 patients (4%). The prevalence in controls, H2RA, PPI and VPZ groups was 1.9% (11/580), 1.5% (1/65), 6.2% (9/146) and 8.7% (27/310), respectively. Both the PPI and VPZ groups had a significantly higher prevalence of gastric mucosal redness compared with the control group (P<0.001). In the multivariate analysis, PPI and VPZ use were significantly associated with gastric mucosal redness. Fundic gland polyps, gastric hyperplastic polyps, multiple white and flat elevated lesions, cobblestone-like mucosa, and stardust gastric mucosa were also significantly associated with PPI and VPZ use in the multivariate analysis. Back-to-back analysis showed that gastric mucosal redness was not seen before starting PPI/VPZ in most patients. The duration of treatment with VPZ was investigated to determine if it affected the prevalence of gastric mucosal redness. There were no significant differences in treatment duration among patients with and without gastric mucosal redness (mean ± standard deviation: 3.0±1.5 vs. 2.5±1.4 years, P=0.077). In conclusion, the prevalence of gastric mucosal redness was low but was associated with PPI and VPZ use.

BACKGROUND: Pneumatosis intestinalis (PI) is a rare condition characterized by gas collection in the intestinal wall. We aimed to determine the etiology and affected segments associated with complications, treatment, and outcome. METHODS: We conducted a multicenter epidemiological survey using a standardized data collection sheet in Japan. Complicating PI was defined as strangulation or bowel necrosis, bowel obstruction, adynamic ileus, sepsis, shock, and massive gastrointestinal bleeding requiring blood transfusion. RESULTS: We enrolled 167 patients from 48 facilities. Multivariate analysis revealed that older age (adjusted OR, 1.05 and 95% confidence intervals [CI], 1.02-1.09, P = 0.0053) and chronic kidney disease (adjusted OR, 13.19 and 95% CI 1.04-167.62, P = 0.0468) were independent predictors of the small-bowel-involved type. Complicating PI was associated with the small-bowel-involved combined type (adjusted OR, 27.02 and 95% CI 4.80-152.01, P = 0.0002), the small-bowel-only type (adjusted OR, 3.94 and 95% CI 1.02-15.27, P = 0.0472), and symptomatic PI (adjusted OR, 16.24 and 95% CI 1.82-145.24, P = 0.0126). Oxygen therapy was performed in patients with a past history of bowel obstruction (adjusted OR, 13.77 and 95% CI 1.31-144.56, P = 0.0288) and surgery was performed in patients with complicating PI (adjusted OR, 8.93 and 95% CI 1.10-72.78, P = 0.0408). Antihypertensives (adjusted OR, 12.28 and 95% CI 1.07-140.79, P = 0.0439) and complicating PI (adjusted OR, 11.77 and 95% CI 1.053-131.526; P = 0.0453) were associated with exacerbation of PI. The complicating PI was the only indicator of death (adjusted OR, 14.40 and 95% CI 1.09-189.48, P = 0.0425). DISCUSSION: Small-bowel-involved type and symptomatic PI were associated with complications which were indicators of poor prognosis.

Whole-block imaging (WBI) using micro-computed tomography (micro-CT) allows the nondestructive reconstruction of a three-dimensional view of tissues, implying that WBI may be used for accurate pathological evaluation of patients with rectal cancer. HOWEVER, the clinical impact of this approach is unclear. We aimed to clarify the efficacy of WBI in the whole-mount specimens of locally advanced rectal cancer. A total of 237 whole-mount formalin-fixed paraffin-embedded blocks from 13 patients with rectal cancer who underwent surgical treatment were enrolled and scanned with micro-CT to generate three-dimensional images. WBI was evaluated following the conventional pathological review of the corresponding whole-slide imaging (WSI). WBI identified all tumor sites detected using WSI. Furthermore, WBI revealed one additional tumor site, which was not detected using WSI. Tumor resection margin was significantly closer to the soft-tissue edge when measured using WBI (7.7 mm vs. 6.6 mm, p &lt; 0.01). Seventy-six percent of tumor deposits on WSI were changed according to the evidence of tumor interaction with the surrounding tissues confirmed using WBI. Furthermore, WBI revealed 25 additional lymph nodes, six of which were metastatic. The combination of conventional hematoxylin and eosin-stained imaging and WBI may contribute to an accurate pathological assessment.

BACKGROUND: Serrated polyposis syndrome (SPS), a type of colorectal polyposis characterized by multiple serrated polyps, is associated with a high risk of colorectal carcinoma (CRC). This study aimed to clarify the clinicopathological characteristics of SPS in Japan. METHODS: We investigated the clinicopathological characteristics of patients with SPS from the "Multicenter Study on Clinicopathological Characteristics of SPS (UMIN 000032138)" by the Colorectal Serrated Polyposis Syndrome (SPS) Study Group. In this study, patients were diagnosed with SPS based on the 2019 World Health Organization (WHO) SPS diagnostic criteria. RESULTS: Ninety-four patients were diagnosed with SPS in 10 institutions between January 2001 and December 2017. The mean number (± standard deviation [SD]) of resected lesions per patient was 11.3 ± 13.8. The mean age at diagnosis of SPS was 63.3 ± 11.6 years, and 58 patients (61.7%) were male. Eighty-seven (92.6%) and 16 (17.0%) patients satisfied WHO diagnostic criteria I and II, respectively. Nine patients (9.6%) satisfied both criteria I and II. Carcinoma (T1-T4) were observed in 21 patients (22.3%) and 24 lesions. Of the 21 patients with CRC, 19 (90.4%) satisfied diagnostic criterion I, 1 (4.8%) satisfied diagnostic criterion II, and 1 (4.8%) satisfied diagnostic criteria I and II. There was no notable difference in the prevalence of CRC among patients who met diagnostic criterion I, II, and both I and II. CONCLUSIONS: Patients with SPS have a high risk of CRC and should undergo regular surveillance colonoscopy. Raising awareness of this syndrome is crucial.

Background and Study Aims: The resection strategy for rectal neuroendocrine tumors (NET) < 10 mm is not uniform. We compared the utility of underwater endoscopic mucosal resection (UEMR) to endoscopic submucosal resection with a ligation device (ESMR-L) to resect rectal NETs. Patients and Methods: Patients with rectal NET < 10 mm treated with UEMR or ESMR-L were included. Their medical records were retrospectively reviewed. Results: Thirty-two patients were divided into a UEMR group (n = 7) and an ESMR-L group (n = 25). Histopathological diagnosis of NET by biopsy was known before resection in 43% (3/7) in the UEMR group and 68% (17/25) in the ESMR-L group, (p = 0.379). UEMR was performed on an outpatient basis for all patients, and 92% of ESMR-L (23/25) were performed as inpatient procedures (p < 0.001). The procedure time was significantly shorter in the UEMR group than in the ESMR-L group [median (IQR), min, 6 (5-8) vs. 12 (9-14), p = 0.002]. En bloc resection and R0 resection rates were 100% in both groups. Pathological evaluations were predominantly NET G1 in both groups (UEMR: 7/7, 100% and ESMR-L: 23/25, 92%). Two patients in the ESMR-L group developed delayed bleeding, controlled by endoscopic hemostasis. Device costs were significantly higher in the ESMR-L group than the UEMR group by approximately US$180 [median (IQR), $90.45 (83.64-108.41) vs. $274.73 (265.86-292.45), P < 0.001]. Conclusion: UEMR results in similar resection quality with shorter procedure time and lower costs compared to ESMR-L. We recommend UEMR for the resection of rectal NET < 10 mm.

Background and study aims  Endoscopic submucosal dissection (ESD) of superficial gastric lesions involving the pyloric ring is difficult. The pocket-creation method (PCM) with a small-caliber-tip transparent hood can overcome this difficulty by compressing the pyloric sphincter applying both traction and counter-traction. The aim of this study is to clarify the usefulness of the PCM for ESD of superficial gastric neoplasms involving the pyloric ring compared to the conventional method (CM). Patients and methods  From October 2006 to August 2019, 66 gastric lesions requiring duodenal submucosal dissection beyond the pyloric ring in 66 patients were resected. The CM was mainly performed in the first period (CM group, n = 46) and the PCM in the second period (PCM group, n = 20). We retrospectively reviewed their medical records. Results  Although no significant differences were observed in en bloc resection rates between the two groups, the PCM group had a significantly higher R0 resection rate than the CM group ( P  = 0.047). There were no holes in resected specimens in the PCM group while three specimens in the CM group had a hole. The dissection speed in the PCM group tended to be higher than in the CM group, although it did not reach statistical significance ( P  = 0.148). No significant differences were observed for the incidence of adverse events. Conclusions  This is the first study reporting the advantages of the PCM over the CM for ESD of gastric lesions involving the pyloric ring. We believe that the PCM is an effective strategy to compress the pyloric sphincter and facilitates R0 resection.

BACKGROUND: To decrease the risk of bleeding or perforation, ischemic polypectomy is performed using a detachable snare or endoclip with double-balloon endoscopy (DBE) for small-bowel polyps in patients with Peutz - Jeghers syndrome. The aim of this study was to determine the effectiveness and feasibility of ischemic polypectomy. METHODS: We retrospectively reviewed patients who underwent two or more sessions of ischemic polypectomy using DBE from July 2004 to August 2017. RESULTS: 67 therapeutic DBEs were performed in nine patients during the study period and 352 polyps were treated. The median observation period was 34 months (range 12 - 66). There was a declining trend over time in the median number of polyps > 15 mm treated per patient first DBE session 6, second 2, third 1.5, fourth 0.5, fifth 0.5; P = 0.11, Friedman test). No patient required laparotomy due to intussusception during the study period. One patient developed mild acute pancreatitis after the procedure. CONCLUSIONS: Ischemic polypectomy was feasible for the control of small-bowel polyps in patients with Peutz - Jeghers syndrome.

BACKGROUND : Many patients with familial adenomatous polyposis (FAP) have adenomatous polyps of the duodenum and the jejunum. We aimed to elucidate the long-term outcomes after double-balloon endoscopy (DBE)-assisted endoscopic resection of duodenal and jejunal polyps in patients with FAP. METHODS : We retrospectively reviewed patients who underwent more than two sessions of endoscopic resection using DBE from August 2004 to July 2018. RESULTS : A total of 72 DBEs were performed in eight patients (median age 30 years, range 12-53; 1.4 DBE procedures/patient-year) during the study period, and 1237 polyps were resected. The median observation period was 77.5 months (range 8-167). There were 11 adverse events, including seven delayed bleeds and four episodes of acute pancreatitis. No delayed bleeding occurred after cold polypectomy. Although, in one patient, one endoscopically resected duodenal polyp was diagnosed as being intramucosal carcinoma, none of the patients developed an advanced duodenal or jejunal cancer during the study period. CONCLUSIONS : Endoscopic resection of duodenal and jejunal polyposis using DBE in patients with FAP can be performed safely, efficiently, and effectively.

BACKGROUND: A novel potassium-competitive acid blocker, vonoprazan (VPZ), improves first-line Helicobacter pylori eradication success. The aim of this systematic review is to clarify the effectiveness and safety of second-line H. pylori eradication therapy comparing VPZ and proton pump inhibitor (PPI)-based regimens. METHODS: Medline (PubMed), EMBASE, Web of Science, Cochrane Library, and the Japan Medical Abstract Society Database were searched. RESULTS: We selected 16 studies for quantitative review. Forest plot analysis showed significant superiority of VPZ over PPI-based regimens in overall second-line H. pylori eradication success (OR 1.51, 95% CI 1.27-1.81, p < 0.001). Forest plots from 2 studies with propensity score matched analysis showed significant superiority of VPZ over PPI-based regimens (OR 3.09, 95% CI 1.71-5.58, p < 0.001). The remaining 14 studies with per-protocol analysis and the full analysis set also showed significant superiority (OR 1.40, 95% CI 1.16-1.69, p < 0.001). Regarding adverse events, Forest plot analysis did not show a significant difference between the 2 regimens (OR 0.88, 95% CI 0.58-1.32, p = 0.53). CONCLUSIONS: A VPZ-based regimen has significant superiority over a PPI-based regimen for second-line H. pylori eradication therapy. A VPZ-based second-line H. pylori eradication regimen can be the first choice.

Dysbiotic microbiota contributes to the pathogenesis of Crohn's disease (CD) by regulating the immune system. Although pro-inflammatory microbes are probably enriched in the small intestinal (SI) mucosa, most studies have focused on fecal microbiota. This study aimed to examine jejunal and ileal mucosal specimens from patients with CD via double-balloon enteroscopy. Comparative microbiome analysis revealed that the microbiota composition of CD SI mucosa differs from that of non-CD controls, with an increased population of several families, including Enterobacteriaceae, Ruminococcaceae, and Bacteroidaceae. Upon anaerobic culturing of the CD SI mucosa, 80 bacterial strains were isolated, from which 9 strains representing 9 distinct species (Escherichia coli, Ruminococcus gnavus, Klebsiella pneumoniae, Erysipelatoclostridium ramosum, Bacteroides dorei, B. fragilis, B. uniformis, Parabacteroides distasonis, and Streptococcus pasteurianus) were selected on the basis of their significant association with CD. The colonization of germ-free (GF) mice with the 9 strains enhanced the accumulation of TH1 cells and, to a lesser extent, TH17 cells in the intestine, among which an E. coli strain displayed high potential to induce TH1 cells and intestinal inflammation in a strain-specific manner. The present results indicate that the CD SI mucosa harbors unique pro-inflammatory microbiota, including TH1 cell-inducing E. coli, which could be a potential therapeutic target.

BACKGROUND AND AIM: Linked color imaging (LCI) is a novel image-enhancing technology which enhances color differences between a colorectal lesion and surrounding mucosa with enough brightness to illuminate the wide colorectal lumen. The aim of this study is to compare colorectal polyp detection using LCI with that using white light imaging (WLI). METHODS: Randomized controlled trials and prospective studies comparing LCI with WLI for colorectal polyp detection were selected. Outcomes included overall polyp/adenoma detection and additional polyp detection at a second observation. Outcomes were documented by pooled risk ratios (RR) with 95% confidence interval (CI) using the Mantel-Haenszel random effect model. RESULTS: Seven studies were included. LCI showed significant superiority for polyp and adenoma detection compared with WLI (RR 1.16, 95% CI 1.09-1.25, P < 0.001 for polyp detection; RR 1.26, 95% CI 1.14-1.39 P < 0.001 for adenoma detection). LCI significantly increased the number of polyps detected per patient compared with WLI (mean difference 0.27, 95% CI 0.01-0.53, P = 0.040). LCI significantly increased the number of adenomas detected per patient compared with WLI (mean difference 0.22, 95% CI 0.08-0.36, P = 0.002). LCI significantly increased the number of flat polyps detected per patient compared with WLI (mean difference 0.14, 95% CI 0.01-0.27, P = 0.040). LCI had a significantly higher rate of additional polyp detection compared with WLI in the right colon (RR 2.68, 95% CI 1.71-4.19, P < 0.001). CONCLUSIONS: Linked color imaging has significantly greater polyp and adenoma detection rates and detection rate of previously missed polyps compared with WLI. We recommend the initial use of LCI for routine colonoscopy.

BACKGROUND AND AIMS: Colorectal endoscopic submucosal dissection (ESD) is recognized as a challenging procedure. Previously, we reported that a new ESD strategy using the pocket-creation method (PCM) is useful for colorectal ESD, but no prospective randomized study has evaluated the efficacy of the PCM. The aim of this study was to evaluate the efficacy and safety of PCM for colorectal ESD compared with the conventional method (CM). METHODS: This was a prospective randomized controlled trial at 3 institutions in Japan. Patients with superficial colorectal neoplastic lesions >20 mm predicted to be intramucosal were randomly assigned to undergo ESD using the PCM or CM. Primary outcome was the ESD completion rate defined as completion of colorectal ESD with an en bloc resection using the assigned ESD method without changing to other methods or assisted by other devices. RESULTS: We analyzed 59 patients with 59 colorectal tumors in the PCM group and 55 in the CM group. The ESD completion rate was significantly higher in the PCM group compared with the CM group (93% [55/59] vs 73% [40/55]; P  = .01). En bloc resection rates, R0 resection rates, procedure time, and dissection speed were not significantly different between the 2 groups. The incidence of adverse events was similar in the 2 groups. CONCLUSIONS: Use of the PCM allows the endoscopist to complete the procedure with the intended method more often than the CM with similar clinical outcomes. (Clinical trial registration number: UMIN 000024394.).

Background and study aims  Resecting large colorectal sessile tumors using endoscopic submucosal dissection (ESD) is challenging because of severe submucosal fibrosis. Previously, we reported that ESD strategy using the pocket-creation method (PCM) is useful for large colorectal sessile tumors, but there are no large studies reporting the effectiveness and safety of the PCM for resection of large colorectal sessile tumors. Patients and methods  This was a retrospective review of 90 large colorectal sessile tumors in 89 patients who underwent ESD in our institution. Large colorectal sessile tumors were defined as polypoid lesions 20 mm or more in diameter. We divided them into PCM (n = 40) and conventional method (CM) groups (n = 50). The primary outcome measure was en bloc resection. The inverse-probability-treatment weighting (IPTW) approach was used to adjust for selection bias. Results  Both PCM and CM achieved high en bloc resection (100 % vs. 94 %, non-adjusted P  = 0.25, IPTW-adjusted P  = 0.19) and R0 resection rates (88 % vs. 78 %, non-adjusted P  = 0.28, IPTW-adjusted P  = 0.27). When PCM was used, the rate of pathologically negative vertical margins was significantly greater than with the CM (IPTW-adjusted P  = 0.045). The dissection time was significantly shorter (IPTW-adjusted P  = 0.025) and dissection speed faster (IPTW-adjusted P  = 0.013) using the PCM than when the CM was used. There was no significant difference in the incidence of adverse events (intraprocedural perforation and delayed bleeding, IPTW-adjusted P  = 0.68). Conclusion  Although en bloc resection and R0 resection rates were similar, PCM significantly increased the rate of negative vertical margins with rapid dissection for treatment of large colorectal sessile tumors.

BACKGROUND & AIMS: We compared the diagnostic accuracy of the fecal calprotectin (FCP) test vs the fecal immunochemical blood test (FIT) in determining the endoscopic severity and predicting outcomes of patients with ulcerative colitis (UC). METHODS: We performed a nationwide study of 879 patients with UC, enrolled at medical centers across Japan, from March 2015 to March 2017. We collected data on fecal biomarkers, endoscopic severities, and other clinical indices from Cohort 1 (n = 427) and assessed the diagnostic accuracy of FCP measurement and FIT results in determining clinical severity, based on Mayo score, and endoscopic remission, based on Mayo endoscopic sub-score (MES) or UC endoscopic index of severity. We also followed 452 patients in clinical remission from UC (Cohort 2) for 12 months and evaluated the associations of FCP levels and FIT results with clinical recurrence. RESULTS: The levels of FCP and FIT each correlated with the MES and UC endoscopic index of severity. There were no significant differences in the areas under the curve of FCP vs FIT in distinguishing patients with MES≤1 from those with MES≥2 (P = .394) or in distinguishing patients with MES=0 from those with MES≥1 (P = .178). Among 405 patients in clinical remission at baseline, 38 (9.4%) had UC recurrences within 3 months and 90 (22.2%) had recurrences within 12 months. FCP≥146 mg/kg (hazard ratio [HR], 4.83; 95% confidence interval [CI], 2.80-8.33) and FIT≥77 ng/mL (HR, 2.92; 95% CI, 1.76-4.83) were independently associated with clinical recurrence within 12 months. UC recurred within 12 months in 69% of patients with levels of FCP≥146 mg/kg and FIT ≥77 ng/mL; this value was significantly higher than the rate of recurrence in patients with levels of FCP≥146 mg/kg and FIT <77 ng/mL (31.5%, P < .001) or patients with levels of FCP<146 mg/kg and FIT ≥77 ng/mL (30.0%, P < .001). CONCLUSION: In a nationwide study of patients with UC in Japan, we found that the level of FCP and FIT could each identify patients with endoscopic markers of disease severity (MES≥2). The combination of FCP and FIT results can identify patients in remission who are at risk for disease recurrence. Clinical Trials Registry no: UMIN000017650 (http://www.umin.ac.jp/ctr/).

BACKGROUND/AIMS: The long-term outcomes of patients after cessation of acotiamide therapy in patients with functional dyspepsia remains unclear. The aim of this study is to investigate the timing and predictors of recurrence of dyspepsia symptoms after cessation of acotiamide therapy for functional dyspepsia. METHODS: Seventy patients treated with acotiamide for functional dyspepsia who then ceased treatment were enrolled. Changes in dyspepsia symptoms were evaluated using the Izumo scale, a self-reporting questionnaire of abdominal symptom-related quality of life. Patients were subclassified into epigastric pain, postprandial distress, and overlapped types. RESULTS: The mean follow-up after cessation of acotiamide was 1.9 years. After cessation of acotiamide, 39 patients (56%) had recurrence. Kaplan-Meier analysis revealed a recurrence-free rate of 51% at 1 year. Predictors of recurrence evaluated with a Cox proportional hazards model showed that overlapped-type dyspepsia and consultation with the treating physician before cessation were identified as significant positive and negative predictors, respectively (p < 0.05). The resumption of acotiamide significantly decreased the score for dyspepsia symptoms at 1 month. CONCLUSIONS: Dyspepsia symptoms recur about one year after cessation of acotiamide therapy. Patients with overlapped-type dyspepsia should be carefully followed after cessation. Patients should consult their treating physician before stopping acotiamide.

A 67-year-old woman presented with symptoms of bowel obstruction. Radiographic and ultrasonographic findings suggested colo-colonic intussusception caused by a colonic lipoma. Colonoscopy with an endoscope tip balloon was performed for reduction. The intussusception was partially reduced by injecting dilute contrast media with a wedged inflated balloon at the endoscope tip. For definitive treatment of the polyp, ischemia was induced using a detachable snare. The abdominal pain well improved after endoscopic treatment. However, ultrasonography suggested a residual lesion. Another detachable snare was applied to the stalk on day 6. A large amount of dark-red necrotic tissue was passed per anus the following day. One month later, complete scarring of the site was confirmed colonoscopically. This is the first report of curative endoscopic treatment of an intussusception due to a giant colonic lipoma with detachable snares after the reduction with a wedged balloon of colonoscope tip.

BACKGROUND AND AIMS: Colonic endoscopic submucosal dissection (ESD) is more difficult than rectal ESD because of poor maneuverability of the endoscope due to physiologic flexion, peristalsis, and respiratory movements. The aim of this study was to assess the usefulness of the pocket-creation method (PCM) for colonic ESD compared with the conventional method (CM) regardless of lesion shape or location. METHODS: A total of 887 colorectal lesions were treated by ESD. Of 887 lesions, 271 rectal lesions, 72 lesions smaller than 20 mm in diameter, and 1 non-neoplastic lesion were excluded. This is a retrospective chart review of the remaining 543 colon lesions in 512 patients. We divided them into the PCM group (n = 280) and the CM group (n = 263). The primary outcome was the en bloc resection rate. Secondary outcomes were R0 resection (en bloc resection with negative margin), adverse events, dissection time (in minutes), and dissection speed (in mm2/min). RESULTS: The PCM group achieved a significantly higher en bloc resection rate (PCM, 100% [280/280], vs CM, 96% [253/263]; P < .001) and R0 resection rate (91% [255/280] vs 85% [224/263], respectively; P = .033) than the CM group. Dissection time was similar (69.5 ± 44.4 vs 78.7 ± 62.6 minutes, P = .676). Dissection speed was significantly faster with the PCM than with the CM (23.5 ± 11.6 vs 20.9 ± 13.6 mm2/min, P < .001). The incidence of adverse events was similar (perforation, 2% vs 4% [P = .152], and delayed bleeding, 2% vs 1% [P = .361]). CONCLUSIONS: Colonic ESD using the PCM significantly improves the rates of en bloc resection and R0 resection and facilitates rapid dissection.

Strictures of the small intestine are a significant complication in patients with Crohn’s disease. Their treatment remains a major challenge. Surgical resection cannot cure Crohn’s disease. Multiple resection of strictures may lead to short bowel syndrome. The development of balloon-assisted enteroscopy has enabled balloon dilation for strictures in the deep small bowel. Because balloon dilation can be repeatedly performed for recurrence of strictures, it may avoid or postpone the need for surgery. In this article, we introduce strategies and devices for endoscopic balloon dilation therapy for Crohn’s disease strictures.

Background/Aims: A submucosal cushion of sodium hyaluronate facilitates gastric and colorectal endoscopic submucosal dissection (ESD). However, few studies have evaluated the utility of sodium hyaluronate for ESD of esophageal lesions. The aim of this study is to evaluate the utility and safety of sodium hyaluronate for ESD of superficial esophageal squamous cell neoplasms (ESCN). Material and methods: We retrospectively reviewed 111 ESCN in 86 patients treated by ESD between September 2007 and April 2013. There were four double cancers, with 107 ESD procedures analyzed. Results: The en bloc resection rate was 99% (106/107). The R0 resection rate was 93% (99/107). Of 106 specimens resected en bloc, four specimens had a positive horizontal margin, two specimens had non-assessable horizontal margins and one specimen had non-assessable horizontal and vertical margins. One patient with a non-assessable horizontal margin developed local recurrence seven months later, treated by repeat ESD. Delayed bleeding occurred in two procedures (2%), and intra-procedural perforation occurred in four (4%). None required operative repair. Endoscopy trainees performed 33 of 107 (31%) ESD procedures. Post-ESD stenosis requiring dilation occurred following five procedures (5%). Conclusions: Sodium hyaluronate for ESD of ESCN achieves a high R0 resection rate with a low rate of adverse events.