Clinical characteristics and long-term prognosis of type 1 gastric neuroendocrine tumors in a large Japanese national cohort.

OBJECTIVES: Optimal management of type 1 gastric neuroendocrine tumors (T1-GNETs) remains unknown, with few reports on their long-term prognosis. This study investigated the clinical characteristics and long-term prognosis of T1-GNETs. METHODS: We reviewed the medical records of patients diagnosed with T1-GNET during 1991-2019 at 40 institutions in Japan. RESULTS: Among 172 patients, endoscopic resection (ER), endoscopic surveillance, and surgery were performed in 84, 61, and 27, respectively, including 27, 77, and 2 patients with pT1a-M, pT1b-SM, and pT2 tumors, respectively. The median tumor diameter was 5 (range 0.8-55) mm. Four (2.9%) patients had lymph node metastasis (LNM); none had liver metastasis. LNM rates were significantly higher in tumors with lymphovascular invasion (LVI) (15.8%; 3/19) than in those without (1.1%; 1/92) (P = 0.016). For tumors <10 mm, LVI and LNM rates were 18.4% (14/76) and 2.2% (2/90), respectively, which were not significantly different from those of tumors 10-20 mm (LVI 13.3%; 2/15, P = 0.211; and LNM 0%; 0/17, P = 1.0). However, these rates were significantly lower than those of tumors >20 mm (LVI 60%; 3/5, P = 0.021; and LNM 40%; 2/5, P = 0.039). No tumor recurrence or cause-specific death occurred during the median follow-up of 10.1 (1-25) years. The 10-year overall survival rate was 97%. CONCLUSIONS: Type 1 gastric neuroendocrine tumors showed indolent nature and favorable long-term prognoses. LVI could be useful in indicating the need for additional treatments. ER for risk prediction of LNM should be considered for tumors <10 mm and may be feasible for tumors 10-20 mm. TRIAL REGISTRATION: The study protocol was registered in the University Hospital Medical Information Network (UMIN) under the identifier UMIN000029927.

Clinical course and management of adverse events after endoscopic resection of superficial duodenal epithelial tumors: Multicenter retrospective study.

OBJECTIVES: This study aimed to elucidate the clinical course and management of adverse events (AEs) after endoscopic resection (ER) for superficial duodenal epithelial tumors (SDETs). METHODS: Consecutive patients who underwent ER of SDETs between January 2008 and July 2018 at 18 Japanese institutions were retrospectively enrolled. The study outcomes included the clinical course, management, and risk of surgical conversion with perioperative AEs after ER for SDETs. RESULTS: Of the 226 patients with AEs, the surgical conversion rate was 8.0% (18/226), including 3.7% (4/108), 1.0% (1/99), and 50.0% (12/24) of patients with intraoperative perforation, delayed bleeding, or delayed perforation, respectively. In the multivariate logistic analysis, involvement of the major papilla (odds ratio [OR] 12.788; 95% confidence interval [CI] 2.098-77.961, P = 0.006) and delayed perforation (OR 37.054; 95% CI 10.219-134.366, P < 0.001) were significant risk factors for surgical conversion after AEs. Delayed bleeding occurred from postoperative days 1-14 or more, whereas delayed perforation occurred within 3 days in all cases. CONCLUSIONS: The surgical conversion rate was higher for delayed perforation than those for other AEs after ER of SDETs. Involvement of the major papilla and delayed perforation were significant risk factors for surgical conversion following AEs. In addition, reliable prevention of delayed perforation is required for 3 days after duodenal ER to prevent the need for surgical interventions.

Outcomes of endoscopic resection for superficial duodenal tumors: 10 years' experience in 18 Japanese high volume centers.

BACKGROUND: Data on endoscopic resection (ER) for superficial duodenal epithelial tumors (SDETs) are insufficient owing to their rarity. There are two main ER techniques for SDETs: endoscopic mucosal resection (EMR) and endoscopic submucosal dissection (ESD). In addition, modified EMR techniques, such as underwater EMR (UEMR) and cold polypectomy, are becoming popular. We conducted a large-scale retrospective multicenter study to clarify the detailed outcomes of duodenal ER. METHODS: Patients with SDETs who underwent ER at 18 institutions from January 2008 to December 2018 were included. The rates of en bloc resection and delayed adverse events (AEs; defined as delayed bleeding or perforation) were analyzed. Local recurrence was analyzed using the Kaplan-Meier method. RESULTS: In total, 3107 patients (including 1017 undergoing ESD) were included. En bloc resection rates were 79.1 %, 78.6 %, 86.8 %, and 94.8 %, and delayed AE rates were 0.5 %, 2.2 %, 2.8 %, and 6.8 % for cold polypectomy, UEMR, EMR and ESD, respectively. The delayed AE rate was significantly higher in the ESD group than in non-ESD groups for lesions < 19 mm (7.4 % vs. 1.9 %; P < 0.001), but not for lesions > 20 mm (6.1 % vs. 7.1 %; P = 0.64). The local recurrence rate was significantly lower in the ESD group than in the non-ESD groups (P < 0.001). Furthermore, for lesions > 30 mm, the cumulative local recurrence rate at 2 years was 22.6 % in the non-ESD groups compared with only 1.6 % in the ESD group (P < 0.001). CONCLUSIONS: ER outcomes for SDETs were generally acceptable. ESD by highly experienced endoscopists might be an option for very large SDETs.

Multicenter study of autoimmune gastritis in Japan: Clinical and endoscopic characteristics.

BACKGROUND AND AIM: In Japan, the prevalence of autoimmune gastritis (AIG) is assumed to be very low. With the recent rapid decrease in Helicobacter pylori (Hp) prevalence, reports on AIG are increasing. This multicenter registry study aimed to clarify the characteristics of AIG, especially its endoscopic appearance. METHODS: A total of 245 patients with AIG from 11 institutions in Japan from January 2010 to October 2016 were included, and their clinical and endoscopic findings were evaluated. RESULTS: Mean age was 67.2 ± 11.4 years, and 63.7% of the participants were women. The most common approach to diagnose AIG was endoscopic examination. Repeated incorrect treatment for Hp infection, due to a false-positive result in 13 C-urea breath test, ranked third among the basis for diagnosis of AIG. Associated gastric lesions were type 1 neuroendocrine tumor (11.4%), adenocarcinoma (9.8%), and hyperplastic polyps (21.1%). Corpus pan-atrophy was the most common appearance (90.1%); however, remnant oxyntic mucosa was found in 31.5% of the patients (flat, localized type, 48.6%). Sticky adherent dense mucus and scattered minute whitish protrusions were also observed in approximately 30% of the patients. Despite the prevailing presumption of the antral mucosa remaining normal, 42.3% of the patients presented with various extents of atrophy, and patchy redness and circular wrinkle-like patterns were both observed in approximately 20% of the patients. CONCLUSIONS: The present study showed some prominent clinical characteristics and endoscopic findings of AIG. We believe that our study will facilitate the diagnosis of potential AIG.

Risk factors for reflux esophagitis after eradication of Helicobacter pylori.

Objective: While there is an association between successful eradication of Helicobacter pylori (HP) and reflux esophagitis (RE), risk factors associated with RE remain obscure. The aim of this study is to determine risk factors associated with the development of RE after HP eradication.Materials and methods: Among all patients treated with successful HP eradication from 2008 to 2016, we retrospectively analyzed those who were free from RE at initial esophagogastroduodenoscopy (EGD) and who were followed up with EGD after eradication. Patients were classified according to the presence or absence of RE at the follow-up EGD. RE was defined as mucosal breaks proximal to the squamous-columnar junction. Demographic data, underlying diseases, medications and endoscopic findings at the initial EGD were compared between patients with and without RE.Results: Among 1575 patients, 142 (9.0%) had RE at the follow-up EGD. The time interval from HP eradication until EGD ranged from 4 to 24 months. The endoscopic grade of RE was higher in males than in females. Multivariate analysis revealed that male sex (odds ratio [OR], 1.51; 95% confidence interval [CI], 1.04-2.24), body mass index ≥25 kg/m2 (OR, 2.91; 95% CI, 2.00-4.22), use of calcium channel blockers (OR, 1.70; 95% CI, 1.12-2.55), and hiatal hernia (OR, 3.46; 95% CI, 2.41-5.00) were associated with the development of RE.Conclusions: Calcium channel blocker use was found to be a risk factor for the development of RE after eradication of HP.

Clinical usefulness of magnifying colonoscopy for the diagnosis of ulcerative colitis-associated neoplasia.

BACKGROUND AND AIM: The aim of this investigation was to evaluate the efficacy of Japanese magnifying colonoscopic classifications for ulcerative colitis-associated neoplasia (UCAN). METHODS: We reviewed the colonoscopy records from 2011 to 2018 at our institutions and identified cases of endoscopically or surgically resected UCAN observed by magnifying narrow-band imaging (NBI) endoscopy and magnifying chromoendoscopy. Association between magnifying endoscopic classification and histopathological findings was investigated retrospectively. Japan NBI expert team (JNET) classification and pit pattern classification were applied. RESULTS: There were 17 patients who had a diagnosis of UCAN. Tumors of types 2A, 2B and 3 by JNET classification correlated with the histopathological findings of low-grade dysplasia (LGD)/high-grade dysplasia (HGD), HGD, and massively submucosal invasive (mSM) carcinoma, respectively. Tumors of types III/IV, VI low irregularity, and VI high irregularity/VN by pit pattern classification were correlated with the histopathological findings of LGD/HGD, HGD, and mSM carcinoma, respectively. CONCLUSIONS: Japan NBI expert team classification and pit pattern classification may be predictive of the histological diagnosis and invasion depth of UCAN. This needs to be investigated prospectively in a large cohort or in a randomized clinical trial.

Continuing use of antithrombotic medications for patients with bleeding gastroduodenal ulcer requiring endoscopic hemostasis: a case-control study.

OBJECTIVE: The aim of this study was to compare clinical characteristics and outcomes of bleeding gastroduodenal ulcer between patients taking antithrombotic medications and those not taking antithrombotic medications. METHODS: We performed a case-control study of 346 patients with endoscopically verified bleeding gastroduodenal ulcer, which included 173 cases taking antithrombotic medications throughout peri-bleeding period and 173 age- and sex-matched controls not taking antithrombotic medications. RESULTS: The cases showed less frequent Helicobacter pylori (H. pylori) infections (45.1% versus 60.7%, p = .005), more frequent duodenal location (31.8% versus 19.1%, p = .009), and more frequent rebleeding (13.9% versus 5.8%, p = .02) than the controls. Multivariate analysis revealed that duodenal location (odds ratio [OR] 3.01, 95% confidence interval [CI] 1.37-6.65) and use of antithrombotic medications (OR 2.47, 95% CI 1.13-5.77) were independent factors for rebleeding. However, there were no differences in clinical outcomes, including final successful endoscopic hemostasis, need for surgical intervention, and mortality between cases and controls. Thromboembolic events did not occur in any cases and controls during the periendoscopic period. CONCLUSIONS: Low prevalence of H. pylori infection, frequent duodenal location, and high rebleeding rate are characteristics of patients with bleeding gastroduodenal ulcer under antithrombotic medications. Continuation of antithrombotic medications can be accepted for bleeding gastroduodenal ulcer.

Clinicopathologic Features of Inverted Serrated Lesions of the Large Bowel.

BACKGROUND/AIMS: Serrated lesions (SLs) of the large bowel occasionally manifest as inverted growths with endophytic expansion within the muscularis mucosa. The aims of this investigation were to investigate the incidence of inverted SLs (ISLs) among SLs and to describe the clinicopathologic features. METHODS: We reviewed the colonoscopy records from 2006 to 2014 at our institution and identified cases of endoscopically or surgically resected SLs, including hyperplastic polyps (HPs), sessile serrated adenomas/polyps (SSA/Ps) and traditional serrated adenomas (TSAs). The incidence of ISLs among the SLs and their colonoscopic findings were investigated retrospectively. RESULTS: There were 35 HPs in 30 patients, 80 SSA/Ps in 65 patients and 70 TSAs in 65 patients. The incidence of ISLs was significantly higher among SSA/Ps (8.8%) and HPs (5.7%) than among TSAs (0%; p = 0.04). A predominant right-sided location, a flat-elevated configuration with a central depression and round-open pit pattern or expanded crypt openings were characteristic of ISLs of the SSA/P type. CONCLUSIONS: Right-sided flat lesions with a central depression and round or expanded crypts are indicative of ISLs of the SSA/P type.

Whipple's disease diagnosed using electron microscopy and polymerase chain reaction.

A 50-year-old man presented with bloody diarrhea and 25-kg weight loss over 3 months. Upper and lower endoscopy showed diffuse shaggy white villi in the duodenum and terminal ileum. In addition, capsule endoscopy and double-balloon enteroscopy revealed shaggy white villi in the entire small intestine. Histological examination of biopsy specimens found the lamina propria of the duodenal and intestinal mucosa to be densely infiltrated by rich foamy macrophages that were periodic acid-Schiff-positive. Electron microscopy showed numerous bacilli in the lamina propria. Tropheryma whipplei DNA was detected in the specimens by polymerase chain reaction. Based on these findings, the patient was diagnosed with Whipple's disease. He was treated with a 2-week course of ceftriaxone followed by trimethoprim-sulfamethoxazole. At the 2-month follow up, diffuse white shaggy villi improved dramatically.

Significance of a white opaque substance under magnifying narrow-band imaging colonoscopy for the diagnosis of colorectal epithelial neoplasms.

BACKGROUND AND AIMS: The aim of this study was to examine the significance of a white opaque substance (WOS) found on magnifying narrow-band imaging (M-NBI) for the diagnosis of colorectal neoplastic lesions. METHODS: We retrospectively reviewed colonoscopy records from 2006 to 2012 at our institution and identified cases of endoscopically or surgically resected colorectal epithelial neoplasms observed by M-NBI colonoscopy. The colonoscopic and histologic characteristics of the lesions were compared between WOS-positive and WOS-negative lesions. We further classified the WOS as regular or irregular and compared the histologic characteristics between the two types of lesions. RESULTS: There were 105 WOS-positive lesions and 451 WOS-negative lesions. The former were subdivided into lesions with regular and irregular WOS. The incidence of high-grade dysplasia or carcinoma was significantly higher in WOS-positive lesions (61.9%) than in WOS-negative lesions (28.6%) (P < .05). Among the WOS-positive lesions, massive submucosal invasion was more frequent in lesions with irregular WOS (82.4%) than in those with regular WOS (1.4%) (P < .05). Among cancers with massive submucosal invasion, lymph node metastasis was more frequent in cancers with irregular WOS (17.4%) than in those with regular WOS or without the WOS (0%) (P < .05). CONCLUSIONS: A WOS in colorectal neoplasms may be an optical marker for high-grade dysplasia and cancer. An irregular WOS may be indicative of massive submucosal invasion and lymph node metastasis.

Time trends of the impact of Helicobacter pylori infection and nonsteroidal anti-inflammatory drugs on peptic ulcer bleeding in Japanese patients.

BACKGROUND/AIMS: Helicobacter pylori infection and the use of nonsteroidal anti-inflammatory drugs (NSAIDs) are the main causes of peptic ulcers. The purpose of the present study was to elucidate the time trends of the impact of H. pylori infection and use of NSAIDs and/or antithrombotic agents on peptic ulcer bleeding (PUB) in Japanese patients. METHODS: We retrospectively reviewed 719 patients who had received endoscopic hemostasis for PUB between 2002 and 2013. Subjects were divided into either the first-half group (2002-2007, n = 363) or the second-half group (2008-2013, n = 356). The clinical characteristics of the patients, including the prevalence of H. pylori infection and use of NSAIDs and antithrombotic agents, were compared between the two groups. RESULTS: Compared to the first-half group, patients in the second-half group were characterized by older age (proportion of the patients above 60 years old, 63.9 vs. 76.7%, p = 0.0002), less frequent H. pylori infection (71.6 vs. 57.9%, p < 0.001) and more frequent NSAID intake (39.9 vs. 48.6%, p = 0.02). No significant difference was observed regarding the use of antithrombotic agents between the two groups (18.6 vs. 23.3%, p = 0.13). The prevalence of H. pylori infection and proportion of patients above 60 years old were significantly different between the two groups in a multivariate analysis. CONCLUSION: The main cause of PUB has clearly shifted from H. pylori infection to the use of NSAIDs over the last decade.

Low-Dose Aspirin and Non-steroidal Anti-inflammatory Drugs Increase the Risk of Bleeding in Patients with Gastroduodenal Ulcer.

BACKGROUND: Non-steroidal anti-inflammatory drugs (NSAIDs), low-dose aspirin (LDA), non-aspirin antiplatelet medications (APs), and anticoagulant medications (ACs) increase the risk of gastrointestinal bleeding. AIM: To examine whether NSAIDs, LDA, APs, and ACs use is associated with bleeding from gastroduodenal ulcers. METHODS: This was a case-control study of patients with endoscopically verified gastroduodenal ulcer diagnosed at our institution from 2004 to 2011. Among 1,611 patients, we identified those who required endoscopic hemostasis for bleeding ulcers as cases. Age-matched, sex-matched, and Helicobacter pylori status-matched patients who did not require therapeutic interventions served as controls. Use of NSAIDs, LDA, APs, and ACs within 2 weeks prior to the endoscopy was compared between cases and controls, and effects on ulcer bleeding were calculated. RESULTS: We recruited 341 cases and 668 controls. The site and number of ulcers were not different between groups. Multivariate analyses revealed that LDA and NSAIDs, individually, were associated with the increase in the risk of bleeding (OR 1.80 and 95 % CI 1.18-2.75 for LDA; 1.35 and 1.01-1.80 for NSAIDs). In addition, a combination of LDA and NSAIDs or LDA and APs contributed more profoundly to the bleeding (OR 3.59 and 95 % CI 1.19-10.81 for LDA/NSAIDs; OR 6.70 and 95 % CI 1.83-24.50 for LDA/APs). However, ACs, alone or in combination, were not associated with bleeding ulcers. CONCLUSIONS: Both LDA and NSAIDs are risk factors for upper GI bleeding in patients with gastroduodenal ulcer, while ACs are unrelated to the increased risk. The risk of bleeding with LDA may increase with simultaneous use of APs.

Management and clinical outcomes of type I gastric carcinoid patients: retrospective, multicenter study in Japan.

BACKGROUND AND AIM: Type I gastric carcinoids (TIGC) are associated with chronic atrophic gastritis (CAG) with hypergastrinemia and hyperplasia of enterochromaffin-like cells. Several treatment options are currently available for these tumors including total gastrectomy, partial resection, antrectomy, endoscopic resection and endoscopic surveillance. The present study evaluated different treatment approaches and clinical outcomes of patients with TIGC in Japan. METHODS: Between 1991 and 2011, 82 patients with TIGC were identified at multicenter institutions in Japan. Patient demographics, tumor size, depth of invasion, vessel involvement, treatment approach, Helicobacter pylori infection, serum gastrin level, recurrence-free survival (RFS) and disease-specific survival (DSS) were analyzed. RESULTS: Median age of all patients at the time of diagnosis was 56 years (range, 24-79 years). There were 44 males and 38 females. Patients underwent endoscopic surveillance (n=25), endoscopic resection (n=41) or surgical resection (n=16). Intramucosal invasion was found in 19 patients, submucosal invasion in 44 patients and muscularis propria invasion in one patient. Tumor diameter was ≤ 10 mm in 71 patients, 11-20mm in five patients and ≥ 21 mm in five patients. None of the patients showed rapidly growing tumors, local recurrence or metastasis. The median (range) follow-up period was 7(0-20) years. RFS was 97.6% and DSS was 100% in all the patients. CONCLUSION: The prognosis of TIGC patients treated by different modalities in Japan is favorable regardless of the generational change of management for TIGC.

Clinicopathological features and prognosis of primary small bowel adenocarcinoma: a large multicenter analysis of the JSCCR database in Japan.

BACKGROUND: The clinicopathological features and prognosis of primary small bowel adenocarcinoma (PSBA), excluding duodenal cancer, remain undetermined due to its rarity in Japan. METHODS: We analyzed 354 patients with 358 PSBAs, between January 2008 and December 2017, at 44 institutions affiliated with the Japanese Society for Cancer of the Colon and Rectum. RESULTS: The median age was 67 years (218 males, 61.6%). The average tumor size was 49.9 (7-100) mm. PSBA sites consisted of jejunum (66.2%) and ileum (30.4%). A total of 219 patients (61.9%) underwent diagnostic small bowel endoscopy, including single-balloon endoscopy, double-balloon endoscopy, and capsule endoscopy before treatment. Nineteen patients (5.4%) had Lynch syndrome, and 272 patients (76.8%) had symptoms at the initial diagnosis. The rates for stages 0, I, II, III, and IV were 5.4%, 2.5%, 27.1%, 26.0%, and 35.6%, respectively. The 5-year overall survival rates at each stage were 92.3%, 60.0%, 75.9%, 61.4%, and 25.5%, respectively, and the 5-year disease-specific survival (DSS) rates were 100%, 75.0%, 84.1%, 59.3%, and 25.6%, respectively. Patients with the PSBA located in the jejunum, with symptoms at the initial diagnosis or advanced clinical stage had a worse prognosis. However, multivariate analysis using Cox-hazard model revealed that clinical stage was the only significant predictor of DSS for patients with PSBA. CONCLUSIONS: Of the patients with PSBA, 76.8% had symptoms at the initial diagnosis, which were often detected at an advanced stage. Detection during the early stages of PSBA is important to ensure a good prognosis.

Outcomes of Metastatic and Unresectable Small Bowel Adenocarcinoma in Japan According to the Treatment Strategy: A Nationwide Observational Study.

PURPOSE: Limited information is available regarding the characteristics and outcomes of stage IV small bowel adenocarcinoma (SBA) in Japan. This study examined the clinical and pathological characteristics and outcomes according to the treatment strategies in patients with stage IV SBA. METHODS: This retrospective observational study used the data of patients with jejunal or ileal adenocarcinoma collected by the Small Bowel Malignant Tumor Project of the Japanese Society for Cancer of the Colon and Rectum. Descriptive statistics were expressed as the mean (standard deviation) or median (range). Survival analysis was performed using Kaplan-Meier curves and pairwise log-rank tests. RESULTS: Data from 128 patients were analyzed. The treatment strategies were chemotherapy alone (26 of 128, 20.3%), surgery alone (including palliative surgery; 21 of 128, 16.4%), surgery + chemotherapy (74 of 128, 57.8%), and best supportive care (7 of 128, 5.5%). The median (range) overall survival was 16 (0-125) months overall, and 11 (1-38) months, 8 (0-80) months, 18 (0-125) months, and 0 (0-1) months for the chemotherapy, surgery, surgery + chemotherapy, and best supportive care groups, respectively. Three main categories of chemotherapeutic regimen were used: a combination of fluoropyrimidine and oxaliplatin (F + Ox), fluoropyrimidine and irinotecan (F + Iri), and single-agent fluoropyrimidine. Among patients treated with chemotherapy, the median (range) OS was 16 (1-106) months overall, and 17 (1-87) months, 29 (7-39) months, and 16 (1-106) months in patients treated with fluoropyrimidine, F + Iri, and F + Ox, respectively. CONCLUSION: Patients treated with surgery, chemotherapy, or both had a better prognosis than those who received best supportive care. Among patients who received chemotherapy, survival did not differ according to the chemotherapeutic regimen.

[Present status of gastrointestinal damage due to non-steroidal anti-inflammatory drugs (NSAIDs)].

Non-steroidal anti-inflammatory drugs (NSAIDs) are roughly divided into a low-dose aspirin group used for primary and secondary prevention of cardiovascular events and non-aspirin NSAIDs used for treatment of bone and joint diseases. Both cause gastrointestinal damage directly or indirectly. In the present study, we reviewed gastrointestinal damage due to non-aspirin NSAIDs with respect to the esophagus, stomach/duodenum, small intestine and colon. Damage due to NSAIDs occurs in all digestive tracts and since the analgesic effect of NSIADs hides subjective symptoms, the symptoms are often not treated until they are advanced to a serious state. Further, patients receiving NSAIDs are mostly elderly and have complications so that the onset of the conditions is serious and prevention is important. It is necessary to investigate a method that is effective for preventing damage for all digestive tracts and the mechanisms of damage must be understood for this reason.