Endoscopic and clinical features of gastric emphysema.

Gastric emphysema is characterized by the presence of intramural gas in the stomach without bacterial infection. Due to its rarity, most reports on gastric emphysema have been limited to single-case studies, and this condition's clinical and endoscopic features have not been thoroughly investigated. In this study, we analyzed 45 patients with gastric emphysema from 10 institutions and examined their characteristics, endoscopic features, and outcomes. The mean age at diagnosis of gastric emphysema in our study population (35 males and 10 females) was 68.6 years (range, 14-95 years). The top five underlying conditions associated with gastric emphysema were the placement of a nasogastric tube (26.7%), diabetes mellitus (20.0%), post-percutaneous endoscopic gastrostomy (17.8%), malignant neoplasms (17.8%), and renal failure (15.6%). Among the 45 patients, 42 were managed conservatively with fasting and administration of proton pump inhibitors. Unfortunately, seven patients died within 30 days of diagnosis, and 35 patients experienced favorable recoveries. The resolution of gastric emphysema was confirmed in 30 patients through computed tomography (CT) scans, with a mean duration of 17.1 ± 34.9 days (mean ± standard deviation [SD], range: 1-180 days) from the time of diagnosis to the disappearance of the gastric intramural gas. There were no instances of recurrence. Endoscopic evaluation was possible in 18 patients and revealed that gastric emphysema presented with features such as redness, erosion, coarse mucosa, and ulcers, with fewer mucosal injuries on the anterior wall (72.2%), a clear demarcation between areas of mucosal injury and intact mucosa (61.1%), and predominantly longitudinal mucosal injuries on the stomach folds (50.0%). This study is the first English-language report to analyze endoscopic findings in patients with gastric emphysema.

Usefulness of Acetic Acid Spray with Narrow-Band Imaging for Identifying the Margin of Sessile Serrated Lesions.

BACKGROUND: Sessile serrated lesions (SSLs) are precursors of colon cancer, especially in cases of large, right colon. However, they are difficult to not only detect, but only clarify the margin of the lesion, which can lead to the poor endoscopic treatment outcomes. AIMS: This study evaluated the usefulness of acetic acid spray with narrow-band imaging (A-NBI) for the better visualization of the margin of SSLs. METHODS: From January 2013 to March 2022, patients with superficial elevated polyps suspected of being SSLs ≥ 10 mm with an endoscopic diagnosis that had been endoscopically resected at Hiroshima City Hiroshima Citizens Hospital were enrolled. Endoscopic images with white-light imaging (WLI), narrow-band imaging (NBI), indigo-carmine (IC), and A-NBI were recorded in each lesion and were randomly arranged and assessed by 10 endoscopists. We compared the visibility score (1 to 4) and color differences (ΔE) between inside and outside of the lesions among WLI, NBI, IC, and A-NBI. RESULTS: Forty-one lesions in 33 cases were included, and a total of 164 images were evaluated. As for the visibility score, most of the lesions were scored as 1 or 2 on WLI, whereas most were scored 4 on A-NBI. The median ΔE of A-NBI was also significantly higher than that of WLI, NBI, or IC (20.5 vs. 8.3 vs. 8.2 vs. 12.3, P < 0.01). A significant correlation was observed between the color difference and visibility score (r = 0.53, P < 0.01). CONCLUSIONS: A-NBI may be a useful modality for identifying the margin of SSLs.

Prognosis after curative resection for stage IA gastric cancer in elderly patients: endoscopic submucosal dissection versus surgery.

PURPOSE: To establish whether gastrectomy for early gastric cancer (EGC) in elderly patients is related to poor survival. METHODS: The subjects of this retrospective study were patients aged ≥ 75 years with primary stage IA EGC, who underwent curative resection with endoscopic submucosal dissection (ESD) or surgery. RESULTS: We analyzed data on 365 patients who underwent ESD and 170 patients who underwent surgery. Overall survival (OS) was not significantly different for the ESD group vs. the surgery group (5-year cumulative rates, 81.5% vs. 79.7%; log-rank test, P = 0.506). Multivariate analysis revealed that treatments; namely, ESD or surgery, were not associated with OS (hazard ratio 1.09, 95% confidence interval 0.77-1.51). Similar results were observed even in the subgroups with worse conditions, such as age > 80 years, Eastern Cooperative Oncology Group performance status 2-3, Charlson comorbidity index ≥ 2, and prognostic nutritional index ≤ 46.7. Using propensity score matching, we selected 88 pairs of patients who underwent ESD or surgery with baseline characteristics matched and found that OS was not different between the two groups (log-rank test, P = 0.829). CONCLUSION: OS was comparable for elderly patients who underwent ESD and those who underwent surgery for EGC. Surgical invasiveness did not worsen the prognosis, even for elderly patients.

Application of convolutional neural networks for evaluating the depth of invasion of early gastric cancer based on endoscopic images.

BACKGROUND AND AIM: Recently, artificial intelligence (AI) has been used in endoscopic examination and is expected to help in endoscopic diagnosis. We evaluated the feasibility of AI using convolutional neural network (CNN) systems for evaluating the depth of invasion of early gastric cancer (EGC), based on endoscopic images. METHODS: This study used a deep CNN model, ResNet152. From patients who underwent treatment for EGC at our hospital between January 2012 and December 2016, we selected 100 consecutive patients with mucosal (M) cancers and 100 consecutive patients with cancers invading the submucosa (SM cancers). A total of 3508 non-magnifying endoscopic images of EGCs, including white-light imaging, linked color imaging, blue laser imaging-bright, and indigo-carmine dye contrast imaging, were included in this study. A total of 2288 images from 132 patients served as the development dataset, and 1220 images from 68 patients served as the testing dataset. Invasion depth was evaluated for each image and lesion. The majority vote was applied to lesion-based evaluation. RESULTS: The sensitivity, specificity, and accuracy for diagnosing M cancer were 84.9% (95% confidence interval [CI] 82.3%-87.5%), 70.7% (95% CI 66.8%-74.6%), and 78.9% (95% CI 76.6%-81.2%), respectively, for image-based evaluation, and 85.3% (95% CI 73.4%-97.2%), 82.4% (95% CI 69.5%-95.2%), and 83.8% (95% CI 75.1%-92.6%), respectively, for lesion-based evaluation. CONCLUSIONS: The application of AI using CNN to evaluate the depth of invasion of EGCs based on endoscopic images is feasible, and it is worth investing more effort to put this new technology into practical use.

A prospective multicenter study of the magnifying endoscopic evaluation of the invasion depth of superficial esophageal cancers.

BACKGROUND: Treatment strategies for superficial esophageal squamous cell carcinoma (SESCC) are determined mainly on the basis of the invasion depth. The Japan Esophageal Society (JES) developed a simplified magnifying endoscopic classification for estimating the invasion depth of SESCC. We aimed to evaluate its accuracy. METHODS: We prospectively applied the JES classification for estimating the invasion depth of SESCC to 204 consecutive lesions from 6 hospitals in Japan between April 2016 and October 2018. We analyzed the accuracy of the endoscopic diagnosis by adding the following two categories to the JES classification: ≥ 7 mm lesion in B2 vessels (defined as B2 ≥ 7 mm) and B2 vessels with inflammation (defined as B2i). RESULTS: After applying the exclusion criteria, 201 lesions remained in the analysis. The diagnostic value of type B1, B2, B3 vessels were as follows: sensitivity, 93.9%, 68.0%, 25.0%; specificity, 81.1%, 89.2%, 99.4%; positive predictive value (PPV), 95.6%, 47.2%, 75.0%; negative predictive value (NPV), 75.0%, 95.1%, 95.4%; and accuracy, 91.5%, 86.5%, 95.0%, respectively. A retrospective analysis showed that the diagnostic accuracy was higher in type B2 vessels (86.5% to 92.0%). An avascular area (AVA) was found in 55 (27%) of the 201 lesions, which tended to be associated with a deeper pathological diagnosis of each Type B vessel. In an additional analysis, B2 ≥ 7 mm and B2i improved the diagnostic accuracy of type B2 vessels from 86.5% to 92.0%. CONCLUSIONS: The JES classification is useful for estimating the invasion depth of SESCC. The diagnostic accuracy for type B2 vessels was low, which may be improved by using B2 ≥ 7 mm and B2i.

Vonoprazan versus lansoprazole in the treatment of artificial gastric ulcers after endoscopic submucossal dissection: a randomized, open-label trial.

BACKGROUND: Vonoprazan is more potent and longer acting than traditional proton pump inhibitor. Although vonoprazan is expected to be superior to proton pump inhibitor, its efficacy in the treatment of gastric ulcers following endoscopic submucosal dissection (ESD) is not fully understood. The aim of this study was to evaluate the effectiveness of vonoprazan in artificial ulcer healing following ESD. METHODS: Patients with gastric tumors were randomly assigned to the vonoprazan group (group V) or lansoprazole group (group L) after ESD. Patients received intravenous lansoprazole (30 mg) twice on the day of ESD. Thereafter, patients were treated with vonoprazan (20 mg/day) in group V or lansoprazole (30 mg/day) in group L. Esophagogastroduodenoscopy was performed 4 and 8 weeks after the ESD. RESULTS: A total of 168 patients were analyzed. The 4-week healing rate for artificial ulcer was not significantly higher in group V versus group L (17/85, 20.0% vs. 14/83, 16.9%, respectively). In addition, there were no significant differences between the 4-week shrinkage rates between the two groups. Postoperative bleeding occurred in none of the patients in group V and three in group L. One patient in group V presented delayed perforation 2 days after ESD. CONCLUSIONS: Vonoprazan might not be superior to lansoprazole in the healing of artificial gastric ulcer after ESD. TRIAL REGISTRATION: University hospital Medical Information Network (registration number: UMIN000016642), Registered 27 February 2015, https://www.umin.ac.jp/ctr/index-j.htm.

Association Between Immune-Related Adverse Events and the Prognosis of Patients with Advanced Gastric Cancer Treated with Nivolumab.

BACKGROUND: Little is known about the association between immune-related adverse events (irAEs) and the efficacy and survival outcomes of nivolumab in patients with advanced gastric cancer (AGC). OBJECTIVE: The present study examined the association between irAEs and the prognosis of patients with AGC treated with nivolumab. PATIENTS AND METHODS: From July 2017 to November 2020, patients who had been diagnosed with advanced unresected gastric cancer and treated with nivolumab at our institution were included in this analysis. We compared the clinical and survival outcomes between the irAE and non-irAE groups. We also evaluated the factors associated with better survival in patients treated with nivolumab. RESULTS: A total of 52 patients were included in the present study, and irAEs were observed in 13 (25%). Among the patients with measurable lesions (n = 29), the disease control rates were significantly higher in the irAE group than in the non-irAE group (88 vs. 24%; P = 0.0033). At the 8- and 12-week landmark analyses, the median overall survival (OS) in the irAE group was significantly longer than that in the non-irAE group, whereas the median progression-free survival was comparable between the groups. A multivariate analysis by Cox proportional hazard regression at the 8-week landmark revealed that the development of irAEs (hazard ratio 0.18; 95% confidence interval 0.0099-0.86) alone was positively associated with a longer OS. CONCLUSIONS: The development of irAEs might be associated with survival outcomes with nivolumab treatment in patients with AGC.

Current evidence and issues of endoscopic submucosal dissection for gastric neoplasms during antithrombotic therapy.

Endoscopic submucosal dissection (ESD) for gastric neoplasms is a useful treatment globally. However, postoperative bleeding after gastric ESD is a serious, and sometimes life-threatening complication in patients receiving antithrombotic drugs, because antithrombotic drugs are considered to increase the risk of postoperative bleeding after gastric ESD. In contrast, withdrawal of antithrombotic drugs during the perioperative period increases the risk of thrombotic complications. Guidelines for the management of antithrombotic drugs during the periendoscopic period have been published by different countries, and recent guidelines place greater emphasis on the risk of thromboembolism with the discontinuation of antithrombotic drugs than on the risk of bleeding with the continuation of antithrombotic drugs. Several studies have reported on the validity of these guidelines, and clinical evidence is being established. Most studies reported that gastric ESD under continuation of aspirin or cilostazol did not increase the risk of bleeding, whereas heparin replacement was strongly associated with a higher risk of bleeding. However, the data regarding some clinical issues about the management of antithrombotic drugs, such as the safety of gastric ESD under continuation of thienopyridine, administration of multiple antithrombotic drugs including dual antiplatelet and anticoagulants (warfarin and direct oral anticoagulant), and effective prophylactic methods for postoperative bleeding after gastric ESD are lacking. Larger clinical data are needed to resolve the remaining issues in the future.

Evaluation of the Usefulness and Convenience of the Kyoto Classification of Gastritis in the Endoscopic Diagnosis of the Helicobacter pylori Infection Status.

BACKGROUND/AIMS: The Kyoto Classification of Gastritis was published in 2014. Although this classification is now widely used in Japan, its usefulness and convenience have not been sufficiently evaluated. This study aimed to evaluate the usefulness and convenience of this classification in the endoscopic diagnosis of Helicobacter pylori infection. METHODS: We made a test for the endoscopic diagnosis of H. pylori infection comprising 30 cases who had representative endoscopic features of non-, active, or inactive gastritis. Thirty-eight participants took the test before and after a brief mini-lecture on the Kyoto Classification of Gastritis. Eighteen participants took the test again 3 months later. We investigated the accuracy before, just after, and 3 months after the mini-lecture. RESULTS: The accuracy of endoscopists after the lecture was significantly improved in comparison to before the lecture (77.6 vs. 83.3%). Medical students also showed significantly improved accuracy after the lecture (56.7 vs. 71.7%). Among endoscopists, this improvement was maintained after 3 months. Before the lecture, the accuracy of diagnosing non-gastritis was 90.3%; it tended to be further improved 3 months later (96.5%). A >10% point increase was observed in diagnosing active (72.7-83.3%) and inactive gastritis (73.2-84.3%) at 3 months after the lecture in comparison to before the lecture. CONCLUSION: A brief mini-lecture on the Kyoto Classification of Gastritis improved the accuracy in the endoscopic diagnosis of gastritis, indicating that understanding this classification is useful for the prompt diagnosis of H. pylori infection during esophagogastroduodenoscopy.

Tolerability and efficacy of the concentration of iodine solution during esophageal chromoendoscopy: a double-blind randomized controlled trial.

BACKGROUND AND AIMS: Esophageal chromoendoscopy with iodine solution is an important diagnostic method for the detection of superficial esophageal cancer. However, the concentration of iodine solution has differed among reports. This study aimed to evaluate patient discomfort with different iodine concentrations. METHODS: We performed a prospective, double-blind, randomized study. We prospectively enrolled and analyzed 77 patients who were at high risk for esophageal carcinoma and scheduled to undergo EGD from March 2018 to January 2019. All patients were divided into 2 groups before the procedure to compare pain measurements: a 1% iodine solution group (group A) and a 2% iodine solution group (group B). The primary endpoint of this study was the difference in pain measurement between 1% and 2% iodine solution chromoendoscopy. Secondary endpoints were safety, detection yield, and color evaluation based on both the endoscopist's survey and color values, as determined using the Commission Internationale de l'Eclairage (CIELAB, Vienna, Austria) color evaluation system, in the iodine-faded and iodine-stained area of each group. RESULTS: Heartburn and retrosternal pain in group A were significantly lower than those in group B (P = .02). Eleven patients reported heartburn and retrosternal pain (group A, 2; group B, 9). Four patients reported pain above the sternal angle and 7 below the sternal angle. There was no significant difference between the 2 groups with regard to detection yield, color evaluation by the endoscopist's assessment, or color values. No patients had any adverse events, and all safely completed this study. CONCLUSIONS: The 2% iodine solution resulted in significantly greater pain than the 1% iodine solution, and the color of the stained esophageal images of each group was the same from this study. Therefore, the 1% iodine solution is recommended for esophageal chromoendoscopy. (Clinical trial registration number: UMIN 000029796.).

Postoperative bleeding risk after gastric endoscopic submucosal dissection during antithrombotic drug therapy.

BACKGROUND AND AIM: The safety of gastric endoscopic submucosal dissection (ESD) in the antithrombotic drug users remains controversial. METHODS: Patients who underwent gastric ESD at Okayama University Hospital between March 2006 and February 2016 were enrolled. This study investigated the risk of post-ESD bleeding according to the management of the antithrombotic drugs. RESULTS: One thousand twenty lesions (872 patients) were enrolled. In a multivariate analysis, heparin replacement (odds ratio [OR] 5.0, 95% confidence interval [CI] 1.8-14), multiple antithrombotic drug use (OR 2.9, 95% CI 1.1-6.9), a resected specimen of ≥ 33 mm in diameter (OR 2.7, 95% CI 1.5-5.4), Helicobacter pylori negativity (OR 2.2, 95% CI 1.3-3.7), and tumors located in the lower third of the stomach (OR 1.7, 95% CI 1.0-2.9) were significant risk factors for post-ESD bleeding, while the continuation of aspirin or cilostazol was not (OR 2.6, 95% CI 0.72-7.8). The bleeding rate of the continuation group was comparable with that of the all cessation group among single antithrombotic drug users (4.5% vs 4.4%, P = 1.0); however, the rate of the continuation group was significantly higher than that of the all cessation group among multiple antithrombotic drug users (67% vs 15%, P = 0.020). CONCLUSIONS: The risk of post-ESD bleeding differed according to the management of the antithrombotic drugs. The gastric ESD under the cessation or continuation of aspirin or cilostazol monotherapy was acceptable. However, multiple antithrombotic drug use or heparin replacement was associated with a higher risk of post-ESD bleeding.

Linked color imaging (LCI), a novel image-enhanced endoscopy technology, emphasizes the color of early gastric cancer.

BACKGROUND AND STUDY AIMS: Linked color imaging (LCI) and blue laser imaging (BLI) are novel image-enhanced endoscopy technologies with strong, unique color enhancement. We investigated the efficacy of LCI and BLI-bright compared to conventional white light imaging (WLI) by measuring the color difference between early gastric cancer lesions and the surrounding mucosa. PATIENTS AND METHODS: Images of early gastric cancer scheduled for endoscopic submucosal dissection were captured by LCI, BLI-bright, and WLI under the same conditions. Color values of the lesion and surrounding mucosa were defined as the average of the color value in each region of interest. Color differences between the lesion and surrounding mucosa (ΔE) were examined in each mode. The color value was assessed using the CIE L*a*b* color space (CIE: Commission Internationale d'Eclairage). RESULTS: We collected images of 43 lesions from 42 patients. Average ΔE values with LCI, BLI-bright, and WLI were 11.02, 5.04, and 5.99, respectively. The ΔE was significantly higher with LCI than with WLI ( P  < 0.001). Limited to cases of small ΔE with WLI, the ΔE was approximately 3 times higher with LCI than with WLI (7.18 vs. 2.25). The ΔE with LCI was larger when the surrounding mucosa had severe intestinal metaplasia ( P  = 0.04). The average color value of a lesion and the surrounding mucosa differed. This value did not have a sufficient cut-off point between the lesion and surrounding mucosa to distinguish them, even with LCI. CONCLUSION: LCI had a larger ΔE than WLI. It may allow easy recognition and early detection of gastric cancer, even for inexperienced endoscopists.

Multicenter Prospective Study on the Safety of Upper Gastrointestinal Endoscopic Procedures in Antithrombotic Drug Users.

BACKGROUND: The Japan Gastroenterological Endoscopy Society updated its guidelines for gastroenterological endoscopy in patients undergoing antithrombotic treatment in July 2012. However, the safety of endoscopic procedures in antithrombotic drug users has not been fully investigated. AIMS: To evaluate the safety of upper gastrointestinal endoscopic procedures in antithrombotic drug users. METHODS: From September 2013 to September 2015, patients who were taking antithrombotic drugs and who underwent upper gastrointestinal endoscopic procedures were prospectively enrolled at five hospitals. Incidences of bleeding and thrombosis during endoscopic procedures were evaluated. RESULTS: A total of 270 patients [221 for endoscopic mucosal biopsy and 49 for endoscopic mucosal resection (EMR)/endoscopic submucosal dissection (ESD) were enrolled. The bleeding rate was 0.9% for endoscopic mucosal biopsy and 22% for EMR/ESD, respectively. The bleeding rate after endoscopic mucosal biopsy was not significantly high, even if antithrombotic drugs were continued (0 vs. 1%, P > 0.99), while it was significantly higher among multiple antithrombotic drug users than single drug users (5.9 vs. 0%, P < 0.05). The bleeding rate after EMR/ESD was also higher among multiple antithrombotic drug users than single drug users, but was not significantly different (33 vs. 14%, P = 0.17). Moreover, there were no differences in bleeding rates according to the cessation or continuance of antithrombotic drugs (20 vs. 25%, P = 0.74). There were no thromboembolisms in all cases. CONCLUSIONS: Upper gastrointestinal endoscopic procedures performed under the new guidelines appear acceptable. However, endoscopic procedures among multiple antithrombotic drug users show a greater potential for bleeding.

Endoscopic Resection of a Pedunculated Brunner's Gland Hamartoma of the Duodenum.

A 68-year-old Japanese woman presented with a solitary pedunculated polyp in the duodenum. Endoscopic ultrasonography showed multiple cystic structures in the polyp. The polyp was successfully resected by endoscopic snare polypectomy and pathologically diagnosed as Brunner's gland hamartoma. Because hamartomatous components were not identified in the stalk of the polyp, we speculate that the stalk developed from traction of the normal duodenal mucosa. When a solitary, pedunculated polyp with cystic structure within the submucosa is found in the duodenum, Brunner's gland hamartoma should be considered in the differential diagnosis, despite the rarity of the disease. This case underscores the usefulness of endoscopic ultrasonography for the diagnosis of duodenal subepithelial tumors.

Propofol sedation with a target-controlled infusion pump and bispectral index monitoring system in elderly patients during a complex upper endoscopy procedure.

BACKGROUND AND AIMS: Although the usefulness of propofol sedation during endoscopic submucosal dissection (ESD) for gastric neoplasms was reported previously, information is limited on its use in elderly patients. We investigated the safety and efficacy of propofol sedation with a target-controlled infusion (TCI) pump and bispectral index (BIS) monitoring system (TCI/BIS system) in elderly patients during gastric ESD. METHODS: Included were 413 consecutive gastric ESD procedures involving 455 lesions (379 patients) performed in patients under propofol sedation with a TCI/BIS system between October 2009 and September 2013. Patients were divided into 3 groups: group A, age <70 years (n = 162); group B, age ≥70 and <80 years (n = 171); and group C, age ≥80 years (n = 80). We compared the propofol dose and adverse events (eg, hypotension and hypoxemia) during ESD. RESULTS: Older groups required a lower target concentration of propofol (group A: median 2.1 µg/mL [interquartile range (IQR), 1.9-2.3]; group B: median 1.6 µg/mL [IQR, 1.3-1.8]; and group C: median 1.4 µg/mL [IQR, 1.2-1.6]; P < .0001). Hypotension tended to occur in the younger group, and hypoxemia occurred at a significantly higher rate in the older groups, although the number of cases was small. Low preoperative systolic blood pressure (≤125 mm Hg) was associated with hypotension (odds ratio [OR], 1.73; 95% confidence interval [CI], 1.12-2.70; P = .013) and abnormal pulmonary function was associated with hypoxemia in groups B and C (OR, 4.54; 95% CI, 1.01-31.5; P = .048). CONCLUSIONS: Elderly patients required lower doses of propofol with the TCI/BIS system than younger patients. Attention to hypoxemia is necessary in elderly patients, particularly patients with abnormal pulmonary function.