Search

Background/aims: We investigated the validity and safety of endoscopic submucosal dissection for gastric tumors by examining shortand long-term outcomes by tumor diameter., Materials and Methods: Endoscopic submucosal dissection for gastric tumor was performed on 4259 lesions at our hospital between January 2005 and June 2021. [Study 1] Patients were divided into 5 tumor diameter groups: 3751 lesions, ≤30 mm; 366 lesions, 31-50 mm; 106 lesions, 51-75 mm; 24 lesions, 76-100 mm; and 12 lesions, ≥101 mm. Short-term gastric endoscopic submucosal dissection outcomes were investigated. [Study 2] Long-term outcomes (delayed gastric emptying and prognosis) were investigated in 508 cases with tumor diameter ≥31 mm., Results: [Study 1] Perforation rate (%) was 1.2, 3.6, 3.8, 12.5, and 25.0 for lesions with tumor diameter ≤30 mm, in the range 31-50 mm, 51-75 mm, and 76-100 mm, and ≥101 mm, respectively. Postoperative bleeding rate (%) was 4.8, 9.0, 6.6, 20.8, and 33.3, respectively, R0 resection rate (%) was 96.8, 90.2, 89.6, 70.8, and 66.6, respectively, and curative resection rate (%) was 92.0, 61.2, 63.2, 45.8, and 8.3, respectively. [Study 2] There were 7 cases of delayed gastric emptying after wide resection, with 3 patients requiring balloon dilatation, 1 of whom subsequently underwent distal gastrectomy. Among 205 cases of noncurative resection, 110 underwent additional surgery, residual cancer was present in 11 cases, and lymph node metastasis was observed in 7 cases (1 patient died of disease). To date, 1 of the 95 patients being followed up has died of disease (mean follow-up: 2042 days)., Conclusion: Even with a tumor diameter ≥31 mm, curative resection was achieved in about 60% of cases in which intramucosal lesions were considered possible preoperatively, but the rate was low at 8.3% for tumor diameter ≥101 mm. Long-term outcomes appear favorable, with only 0.4% of the patients dying of disease but delayed gastric emptying observed in 1.7% of cases.

An 86-year-old woman with a subcutaneous nodule in her left axilla visited our hospital. She had no gastrointestinal symptoms, but contrast-enhanced computed tomography revealed a cecal mass and systemic metastasis, including cutaneous, bone, peritoneal dissemination and ascites. Colonoscopy revealed a circumferential, elevated cecal lesion. She underwent right hemicolectomy to prevent colon obstruction. The pathological diagnosis was poorly differentiated adenocarcinoma (por1>tub2>muc) arising from the appendix with a BRAFV600E mutation and microsatellite instability-high. Chemotherapy was administered, and she is currently still alive and undergoing chemotherapy. We describe a rare case of advanced appendiceal cancer without gastrointestinal symptoms diagnosed due to cutaneous metastasis.

Background: Esophageal cancers other than two types, squamous cell carcinoma (SCC) and adenocarcinoma, are commonly referred to as special type of esophageal cancer (STEC). Studies on STECs have been limited because of its low prevalence. Therefore, we aimed to clarify the clinicopathological findings and the long-term outcomes of STECs that were managed with ESD., Methods: We reviewed 713 patients with 1,089 lesions who underwent ESD for primary esophageal cancer except Barrett's esophageal cancer. Patients were classified into the SCC group and the STEC group, respectively. Their clinicopathological findings and long-term outcomes including disease-specific survival (DSS) were collected and examined., Results: A total of 19 consecutive patients (1.7%) were diagnosed with STEC. Nine patients were diagnosed with basaloid carcinoma, 6 with adenosquamous carcinoma, 2 with mucoepidermoid carcinoma, 2 with salivary duct-type carcinoma, and 1 with neuroendocrine cell carcinoma. There was significantly more pT1b esophageal cancer (47.4% vs. 11.0%, p < 0.01) and lymphovascular invasion (31.6% vs. 10.2%, p = 0.011) in the STEC group. Metastatic relapse and disease-specific mortality were significantly higher in the STEC group (both 15.8% vs. 1.2%, p < 0.01), and the STEC group had shorter DSS with 5-year DSS rates of 90.9%. In a subgroup analysis of patients with pT1a esophageal cancer, the 5-year DSS rate was shorter in the STEC group (p < 0.01). In the multivariate analysis, STEC (HR = 0.24) and tumor depth (HR = 12.60) were the factors associated with DSS., Conclusion: STECs are suggested to have high malignant potential and to be an independent negative prognostic factor for DSS., (© 2023 The Author(s). Published by S. Karger AG, Basel.)

Background: Epstein-Barr virus (EBV) is known to be involved in gastric carcinogenesis. EBV-associated early gastric carcinoma (EBVEGC) has a lower incidence of lymph node involvement and could be an expanded indication for endoscopic submucosal dissection (ESD) treatment., Aim: To clarify the prevalence and clinicopathological features of EBVEGC., Methods: This study reviewed 618 lesions in 519 patients treated with ESD between 2014 and 2016. Tissue microarray sections were subjected to in situ hybridization staining for EBV-encoded small RNA transcripts (EBER). Lesions positive for EBER were compared with control lesions and were retrospectively analyzed., Results: 12 (1.9%) of the 618 lesions were EBVEGC. EBVEGCs were more frequently located near the atrophic border than control lesions in the middle or upper stomach and were reddish. EBVEGC invasion was deeper and more often histologically undifferentiated. On narrow-band imaging magnifying endoscopy, the EBVEGC group significantly more often showed an endoscopic lace pattern, defined as an absent or obscure microsurface pattern and a microvascular pattern of a tiny, dense, and irregular subepithelial capillary network. The rate of curative resection was significantly lower in the EBVEGC group., Conclusions: Only 1.9% of the ESD specimens were EBV-positive. Endoscopic features could raise clinical suspicion of EBV infection., (Copyright © 2021. Published by Elsevier Ltd.)

Gastric adenocarcinoma of the fundic gland type (GAFG) has been recently classified by the World Health Organization (WHO), however, clinicopathologic features of pepsinogen I- or H+/K+-ATPase-positive gastric tumors remain unclear. Therefore, this study evaluates the frequency and clinicopathologic features of those tumors, using a tissue microarray block to identify pepsinogen I- or H+/K+-ATPase-positive tumors from 810 endoscopically resected, early gastric epithelial tumors. The frequency of pepsinogen I-positive lesions was 2.1%, and that of H+/K+-ATPase-positive lesions was 2.0%. Pepsinogen I- or H+/K+-ATPase positivity was not observed in undifferentiated-type tumors, while gastric tumors with morphologic similarity to fundic glands were positive for pepsinogen I- or H+/K+-ATPase. We divided pepsinogen I- or H+/K+-ATPase-positive gastric tumors into group A, with fundic gland-like structure, or group B, without fundic gland-like structure. The frequency of group A was 1.6%: 46.2% were positive only for pepsinogen I and 53.8% for H+/K+-ATPase and pepsinogen I. The frequency of group B was 1.5%: 25% were positive only for pepsinogen I, 8.3% for H+/K+-ATPase and pepsinogen I, and 66.7% only for H+/K+-ATPase. The 2 tumor groups differed in location and endoscopic features. Hematoxylin and eosin staining showed that group B had more exposed tumors to the surface, larger nuclei, and more background atrophy than group A. Immunostaining showed significantly higher positivity rates for MUC5AC, CD10, CDX2, and p53 expression, and a higher Ki-67 labeling score. Our results provide novel insights into the pathology of early gastric tumors with histologic or immunohistochemical evidence of fundic gland differentiation., Competing Interests: Conflicts of Interest and Source of Funding: J.H. received a grant from Toranomon Hospital. N.I. and S.H. received a grant from Okinaka Memorial Institute of Medical Research. For the remaining authors none were declared., (Copyright © 2022 Wolters Kluwer Health, Inc. All rights reserved.)

Objective: Patients with acromegaly are at increased risk of colorectal polyps. However, their risk of colorectal cancer remains unclear. This study aimed to identify the histopathological features of colorectal polyps in patients with acromegaly and compare their risk of colorectal cancer with that in healthy controls., Methods: The study participants were 178 patients who underwent Hardy's operation and perioperative colonoscopy at our hospital between April 2008 and September 2016. For the control group, we randomly selected 356 age- and sex-matched patients who underwent colonoscopy at our hospital during the same period. The incidence, size, location, and histology of the colorectal polyps detected were compared between the groups., Results: Colorectal polyps were detected in 66.8% of the acromegaly group and 24.2% of the control group (P < 0.001). The average number and size of the polyps were 2.44 and 4.74 mm, respectively, in the acromegaly group and 1.77 and 3.89 mm in the control group (P = 0.001). Polyps in the acromegaly group were more likely to be in the rectosigmoid region (P = 0.006). In the acromegaly group, the frequency of polyps ≥5 mm was 34.3% and that for polyps ≥10 mm was 15.2%; the respective values were 7.6% and 2.2% in the control group (P < 0.001). We found no evidence of between-group histopathological differences in the polyp specimens resected by endoscopy., Conclusions: Patients with acromegaly are at an increased risk of colorectal polyps, especially in the rectosigmoid region. However, there is no pathological evidence that they are at greater risk of colorectal cancer than the general population.

Background: When a lesion does not meet the curative criteria of endoscopic submucosal dissection (ESD) for early gastric cancer (EGC), referred to as non-curative resection or curability C-2 in the guidelines, an additional surgery is the standard therapy because of the risk of lymph node metastasis (LNM)., Objective: This study aimed to identify high-risk patients for recurrence after additional surgery for curability C-2 ESD of EGC., Methods: This multicenter retrospective cohort study enrolled 1064 patients who underwent additional surgery after curability C-2 ESD for EGC. We evaluated the recurrence rate and the risk factors for recurrence after additional surgery in these patients., Results: The 5-year recurrence rate after additional surgery was 1.3%. Multivariate Cox analysis revealed that the independent risk factors for recurrence after additional surgery were LNM (hazard ratio [HR] 32.47; p < 0.001) and vascular invasion (HR 4.75; p = 0.014). Moreover, patients with both LNM and vascular invasion had a high rate of recurrence after additional surgery (24.6% in 5 years), with a high HR (119.32) compared with those with neither LNM nor vascular invasion. Among patients with no vascular invasion, a high rate of recurrence was observed in those with N2/N3 disease according to the American Joint Committee on Cancer TNM staging system (27.3% in 5 years), in contrast with no recurrence in those with N1 disease., Conclusions: Patients with both LNM (N1-N3) and vascular invasion, as well as those with N2/N3 disease but no vascular invasion, would be candidates for adjuvant chemotherapy after additional surgery for curability C-2 ESD of EGC.

Background and Aims: Cancer recurrence is observed in some patients without additional radical surgery after endoscopic submucosal dissection (ESD) that does not fulfill the curability criteria for early gastric cancer (EGC), categorized as "noncurative resection" or "curability C-2" in the guidelines. However, time to cancer recurrence is different in such patients. Thus, we aimed to identify the risk factors of early and late cancer recurrences in these patients., Methods: Between 2000 and 2011, this multicenter study analyzed 905 patients who were followed up without additional radical surgery after ESD for EGC categorized as curability C-2. We evaluated the risk factors for early and late cancer recurrences, separately, after ESD. The cut-off value was defined at 2 years., Results: Time to cancer recurrence in the enrolled patients showed a bimodal pattern, and the 5-year cancer recurrence rate was 3.2%. Multivariate Cox analyses revealed that lymphatic invasion (hazard ratio [HR], 8.56; P = .003) was the sole independent risk factor for early cancer recurrence. Regarding late cancer recurrence, vascular invasion (HR, 4.50; P = .039) was an independent risk factor, and lymphatic invasion tended to be a risk factor (HR, 3.63; P = .069)., Conclusions: This multicenter study with a large cohort demonstrated that lymphatic invasion is mainly associated with early cancer recurrence; however, vascular invasion was a risk factor only for late recurrence in patients without additional treatment after ESD for EGC categorized as curability C-2. This finding may contribute to decision making for treatment strategies after ESD, especially for patients with a relatively short life expectancy., (Copyright © 2019 American Society for Gastrointestinal Endoscopy. Published by Elsevier Inc. All rights reserved.)

Objectives: A Japanese multicenter prospective cohort study examining endoscopic resection (ER) for early gastric cancer (EGC) has been conducted using a Web registry developed to determine the short-term and long-term outcomes based on absolute and expanded indications. We hereby present the short-term outcomes of this study., Methods: All consecutive patients with EGC or suspected EGC undergoing ER at 41 participating institutions between July 2010 and June 2012 were enrolled and prospectively registered into the Web registry. The baseline characteristics were entered before ER, and the short-term outcomes were collected at 6 months following ER., Results: Nine thousand six hundred and sixteen patients with 10 821 lesions underwent ER (endoscopic submucosal dissection [ESD]: 99.4%). The median procedure time was 76 min, and R0 resections were achieved for 91.6% of the lesions. Postoperative bleeding and intraoperative perforation occurred in 4.4% and 2.3% of the patients, respectively. Significant independent factors correlated with a longer procedure time (120 min or longer) were as follows: tumor size >20 mm, upper-third location, middle-third location, local recurrent lesion, ulcer findings, gastric tube, male gender, and submucosa. Histopathologically, 10 031 lesions were identified as common-type gastric cancers. The median tumor size was 15 mm. Noncurative resections were diagnosed for 18.3% of the lesions. Additional surgery was performed for 48.6% (824 lesions) of the 1695 noncurative ER lesions with a possible risk of lymph node (LN) metastasis. Among them, 64 (7.8%) exhibited LN metastasis., Conclusions: This multicenter prospective study showed favorable short-term outcomes for gastric ESD., (© 2018 Japan Gastroenterological Endoscopy Society.)

Background: We have established a risk-scoring system, termed the "eCura system," for the risk stratification of lymph node metastasis in patients who have received noncurative endoscopic submucosal dissection (ESD) for early gastric cancer (EGC). We aimed to clarify whether this system contributes to the selection of patients requiring radical surgery after ESD., Methods: Between 2000 and 2011, 1,969 patients with noncurative ESD for EGC were included in this multicenter study. Depending on the treatment strategy after ESD, we had patients with no additional treatment (n = 905) and those with radical surgery after ESD (n = 1,064). After the application of the eCura system to these patients, cancer recurrence and cancer-specific mortality in each risk category of the system were compared between the two patient groups., Results: Multivariate Cox analysis revealed that in the high-risk category, cancer recurrence was significantly higher (hazard ratio = 3.13, p = 0.024) and cancer-specific mortality tended to be higher (hazard ratio = 2.66, p = 0.063) in patients with no additional treatment than in those with radical surgery after ESD, whereas no significant differences were observed in the intermediate-risk and low-risk categories. In addition, cancer-specific survival in the low-risk category was high in both patient groups (99.6 and 99.7%). A limitation of this study is that it included a small number of cases with undifferentiated-type EGC (292 cases)., Conclusions: The eCura system is a useful aid for selecting the appropriate treatment strategy after noncurative ESD for EGC. However, caution is needed when applying this system to patients with undifferentiated-type EGC.

Background and Purpose: Previous studies comparing survival outcomes between patients who did and did not undergo additional surgery after non-curative endoscopic submucosal dissection (ESD) for early gastric cancer (EGC) were limited in that the baseline characteristics differed significantly between the groups. We aimed to address this limitation and compared survival outcomes between these two groups using propensity score matching analysis., Methods: The study enrolled 1969 consecutive patients who underwent non-curative ESD for EGC between 2000 and 2011 at any of 19 institutions across Japan. Using propensity score matching analysis, patients who underwent additional surgery (n = 1064) were compared with patients who did not (n = 905). Overall survival (OS) and disease-specific survival (DSS) after ESD were compared between both groups., Results: Propensity score matching analysis yielded 553 matched pairs and well-balanced baseline characteristics between the two groups. The 5-year OS rates were 91.0% in the additional surgery group and 75.5% in the no additional surgery group, and the 5-year DSS rates were 99.0 and 96.8%, respectively. OS and DSS in the additional surgery group were significantly higher than in the no additional surgery group (OS, p < 0.001; DSS, p = 0.013). In Cox proportional hazard analysis, additional surgery significantly reduced gastric cancer-related death after non-curative ESD for EGC (hazard ratio 0.33, 95% confidence interval 0.12-0.79, p = 0.012)., Conclusions: Our findings suggest that additional surgery reduces mortality after non-curative ESD for EGC. We recommend additional surgery for patients after non-curative ESD for EGC.

Background: Endoscopic submucosal dissection (ESD) was developed to resect early gastric cancer (EGC), which could not be resected by conventional endoscopic mucosal resection, and the indications for ESD are expanding to include more types of EGCs. Favorable long-term outcomes of ESD for EGCs that meet the expanded curability criteria have been reported. However, the outcomes of non-curative ESD are not known in detail., Summary: We analyzed the outcomes of 165 EGCs in 165 patients after non-curative ESD, as well as the clinical course. Of these patients, 109 underwent additional surgical resection (group S) and 56 patients were followed up without additional surgery (group F). The complete resection rate was 90.7% (39/43) for intramucosal cancer (M), 97.3% (36/37) for minimally submucosal invasive cancer (SM1), and 74.1% (63/85) for deep submucosal invasive cancer (SM2). The lymph node metastasis rate was 0% for M, 5.4% for SM1, and 10.6% for SM2 cancers. Regarding long-term survival, although the number of patients who died of another disease was significantly higher in group F than in group S, there was no significant difference in overall survival between the groups., Key Message: The resectability of ESD for ECGs with an invasion depth of M to SM1 after non-curative ESD was excellent, and lesions without lymphovascular invasion did not metastasize or recur, resulting in a favorable prognosis. Our data may help in deciding whether additional surgery should be performed for borderline lesions after non-curative ESD. Furthermore, we suggest the possibility of further expanding the indications for ESD., (© 2016 S. Karger AG, Basel.)

Background: Superficial Barrett's esophageal adenocarcinoma (BEA) arising from short-segment Barrett's esophagus (SSBE) is visualized as a reddish lesion located on the right or anterior side wall of the esophagogastric mucosal junction (EGJ) and showing an elevated macroscopic appearance under conventional white light endoscopy (WLE). However, because the form and color are variable, misdiagnosis as reflux esophagitis or SSBE is frequent under WLE. The aim of this study is to clarify conventional WLE features of small superficial BEA., Summary: We retrospectively analyzed 30 lesions ≤20 mm in diameter in 30 patients who underwent endoscopic mucosal resection or endoscopic submucosal dissection at Toranomon Hospital between 2002 and 2014. Mean age of patients with small superficial BEA arising from SSBE was 64.3 ± 11.2 years, and mean tumor size was 12.0 ± 4.8 mm. Small superficial BEA fell into the following 4 categories based on WLE features: EGJ polyp type, 43.3% (13 of 30 lesions); triangular SSBE type, 43.3% (13 of 30 lesions); cardiac erosion type, 10.0% (3 of 30 lesions); and unclassified or mixed type, 3.4% (1 of 30 lesions). EGJ polyp-type tumors were located on the right or anterior side wall of the EGJ, and no tumors showed invasion to the submucosal layer. On the other hand, triangular SSBE-type tumors were located anywhere in the EGJ, and 38.5% showed submucosal invasion (5 of 13 lesions)., Key Messages: We consider this classification significantly contributes to the detection of small superficial BEA arising from SSBE under WLE., (© 2016 S. Karger AG, Basel.)

Esophageal adenocarcinoma arising from ectopic gastric mucosa (EGM) is extremely rare. We describe here two Japanese patients with adenocarcinoma of the cervical esophagus arising from EGM. Case 1 is a 62-year-old man who had slightly red EGM in the cervical esophagus on upper gastrointestinal endoscopy (UGE). Because the biopsy showed atypical glands that were suspicious for adenocarcinoma, endoscopic submucosal dissection was performed. Histopathological examination revealed that the lesion was a well-differentiated adenocarcinoma (pT1a MM). Lymphovascular invasion was absent, and the margins were free from carcinoma. Case 2 is a 57-year-old man who had an elevated lesion with a bleeding tendency in an area of EGM in the cervical esophagus on UGE. Adenocarcinoma was diagnosed in the biopsy. Because of the presence of enlarged lymph nodes (#106recL), preoperative chemoradiotherapy was performed to reduce the size of the adenocarcinoma and lymph nodes prior to resection of the cervical esophagus and reconstruction with free jejunal grafts. Histopathological examination revealed moderately differentiated adenocarcinoma (0-I, pT2N1M0, pStage II). In both cases, adenocarcinoma was surrounded by EGM, which led to the diagnosis of EGM-derived esophageal adenocarcinoma. Here, we report its immunohistochemical characteristics in the present cases and discuss the histogenesis.

Background and Study Aim: Endocytoscopy (ECS) enables in vivo microscopic imaging, which allows analysis of mucosal structures at the cellular level; however, limited data are available on the validity of ECS in the stomach. The aim of this study was to evaluate the feasibility of ECS in the diagnosis of early gastric cancer., Patients and Methods: Gastric lesions that were the targets of histopathological diagnosis by endoscopic submucosal dissection or biopsy specimen were prospectively enrolled and evaluated using a single charge-coupled device-integrated endocytoscope, following double staining with crystal violet and methylene blue. High grade ECS atypia was defined according to specific irregularities in gland structure and cell nuclei. The primary end point was the accuracy of ECS diagnosis for gastric cancer, using histopathological diagnosis as the gold standard., Results: A total of 82 lesions were investigated, including 23 early gastric cancers, 10 gastric adenomas, and 49 non-neoplastic lesions. Ten lesions could not be clearly observed by ECS because of poor staining due to viscous mucus or plaque; thus, assessability rates with ECS were 88 % in total and 91 % for gastric cancer. High grade ECS atypia was observed in 86 % of assessable gastric cancers, but not in any cases of gastric adenomas or non-neoplastic lesions. The sensitivity, specificity, positive and negative predictive values of high grade ECS atypia as the criterion for the diagnosis of gastric cancer were 86 %, 100 %, 100 %, and 94 %, respectively. No serious complications occurred during or after the examinations., Conclusion: ECS is a clinically feasible modality to obtain in vivo histology, with high diagnostic accuracy in gastric cancer., (© Georg Thieme Verlag KG Stuttgart · New York.)

Background: Esophagogastric junction (EGJ) cancers are not only located in regions anatomically difficult for endoscopic submucosal dissection (ESD), but they also have higher clinicopathological malignant potential than non-junctional gastric cancers (NJC). Despite this, no ESD-based comparative studies of junctional cancer (JC) and NJC have been conducted to date. The aims of this study were to clarify the clinicopathological characteristics of EGJ cancers and the short- and long-term outcomes after ESD., Methods: Between April 2005 and December 2010, ESD was performed on 1,463 lesions that were divided into the following three groups: Barrett's adenocarcinoma (BA; n = 25); JC (n = 103), and NJC (n = 1,335). They were assessed for short-term outcomes, clinicopathological malignancy and long-term outcomes., Results: Rates of complete and curative resection were significantly lower for BA than for JC and NJC (64.0 vs. 96.1 and 96.0%; and 48.0 vs. 80.6 and 85.8%, respectively). The perforation rate was significantly higher for BA than for JC and NJC (20.0 vs. 2.9 and 2.7%). Clinicopathologically, submucosal invasion rates were higher in BA and JC than in NJC (32.0 and 30.1 vs. 13.6%), and positive rates of lymphatic and/or vascular invasion were remarkably higher in BA and JC versus NJC (24.0 vs. 9.7 vs. 4.8%, respectively). The 5-year survival rate in all patients with curative resection was 100%., Conclusion: This study confirmed the technical and theoretical validity of ESD for EGJ as a diagnostic treatment. However, we have to pay attention to the high rates of submucosal and lymphovascular invasive malignant potential of these cancers., (Copyright © 2013 S. Karger AG, Basel.)

Background and Aim: Since the first report of gastric adenocarcinoma of the fundic‐gland type in 2010, the clinicopathological characteristics of gastric neoplasm of the fundic‐gland type (GNFG) have become clearer; however, their risk factors remain unclear. This exploratory study aimed to identify the risk factors for GNFG. Methods: We conducted a single‐center, retrospective, matched case–control study using medical information recorded at our health management center from January 2014 to July 2023. During this period, 39 240 people underwent upper gastrointestinal endoscopy. GNFG were extracted as cases and matched to controls, according to age and sex, in a 1:8 ratio, excluding those with a history of gastrointestinal surgery and those with a history or comorbidity of cancer. Univariate analysis was used to compare patient background and endoscopic findings. Multivariable analysis was performed, adjusting for factors with P values < 0.1 and antacid use. Results: A total of 20 GNFG cases and 160 matched healthy controls were included. In the univariate analysis, only reflux esophagitis was significantly more common in GNFG (40.0% vs 18.1%; P = 0.036). Factors antacids and duodenitis had P values < 0.1. Logistic regression analysis was performed, adjusting for antacids, reflux esophagitis, and duodenitis. Antacids and reflux esophagitis were the independent risk factors for GNFG (odds ratio = 3.68 [95% confidence interval: 1.04–11.91] and 3.25 [95% confidence interval: 1.11–9.35]). Conclusions: Although the sample of patients with GNFG was small, antacids and reflux esophagitis were identified as a risk factor. The pathogenesis of antacids and reflux esophagitis may be involved in the development of GNFG. [ABSTRACT FROM AUTHOR]

Aim:Helicobacter pylori-naïve gastric cancers(GCs) have not been well documented. We aimed to characterize early H. pylori-naïve GCs. Subjects and Methods: Of 666 patients with GC resected by endoscopic submucosal dissection, H. pylori-naïve patients were extracted according to the definition: no H. pylori eradication history, negative for serum H. pylori-antibody and current H. pylori-infection tests, and no gastric atrophy by pepsinogen (PG) test, endoscopy, and histology. Results: It was found that 16 GCs were H. pylori-naïve, and classified into undifferentiated and differentiated type adenocarcinoma. All 9 undifferentiated type GCs were pale, depressed, mucosal pure signet ring cell adenocarcinoma except one of them and 7 differentiated type GCs were classified into 3 fundic gland type GCs and 4 foveolar type GCs. All fundic gland type GCs positive for PG-1 were cardia small submucosal tumor (SMT)-like protrusions with dilated vessels on the surface. All 4 foveolar type GCs were composed of dysplastic clear cells resembling foveolar epithelium, negative for PG-1 but positive for mucin 6 (MUC6) and MUC5AC. Endoscopically, all were laterally spreading elevations with papillary or villous surface. Conclusions:H. pylori-naïve GCs were infrequent at 2.5%, and classified into 3 types: a small pale depression of signet ring cell adenocarcinoma, a small SMT-like protrusion of fundic gland type GC, and a large laterally spreading elevation of foveolar type GC. [ABSTRACT FROM AUTHOR]

Background: Superficial non-ampullary duodenal epithelial tumors (SNADETs) are relatively rare, but they are now being detected more frequently due to advances in endoscopic technology. Nevertheless, the pathological nature of SNADETs remains unclear and a management strategy for these tumors has not been established.Methods: To elucidate the clinicopathological features, we conducted a retrospective analysis of 138 endoscopically resected SNADETs. Lesions were classified into two groups by histological grade according to the Vienna classification: category 3 (71 lesions, 51.4%) and category 4/5 (67 lesions, 48.6%).Results: Compared with category 3 lesions, category 4/5 lesions were significantly more common in elderly patients (p < 0.001) and had a significantly larger tumor diameter (p = 0.001). Immunohistochemical analysis showed that category 4/5 lesions expressed MUC5AC (p = 0.002), MUC6 (p < 0.001), and p53 (p = 0.003) significantly more frequently and expressed CD10 (p = 0.002) and CDX2 (p = 0.029) significantly less frequently. Multivariate regression analysis showed that advanced age (p < 0.001), MUC6 expression (p = 0.001), and p53 expression (p = 0.004) were independent risk factors for a classification of category 4/5. In addition, advanced age (p = 0.010) and MUC5AC expression (p = 0.011) were identified as risk factors for lesions classified as category 4.2 (noninvasive carcinoma) or higher. All category 5 lesions expressed MUC5AC.Conclusions: The gastric phenotype of MUC5AC and MUC6 may be linked to the malignant potential of SNADETs. [ABSTRACT FROM AUTHOR]