Innovative submucosal injection solution for endoscopic resection with phosphorylated pullulan: a preclinical study.

BACKGROUND AND AIMS: A submucosal injection solution is used to assist in endoscopic surgery. The high viscosity of current solutions makes them difficult to inject. In the present study, we developed an extremely low-viscosity, easy-to-use submucosal injection solution using phosphorylated pullulan (PPL). METHODS: The PPL solutions were prepared at different concentrations, and their viscosities were measured. The mucosal elevation capacity was evaluated using excised porcine stomachs. Controls included 0.4% sodium hyaluronate (SH), 0.6% sodium alginate (SA), and saline. To evaluate the practicality, the catheter injectability of 0.7% PPL was measured, and EMR and endoscopic submucosal dissection (ESD) were performed using the stomach and colorectum of live pigs. As controls, 0.4% SH and saline were used. RESULTS: The PPL solutions were of extremely low viscosity compared to the solutions of 0.4% SH and 0.6% SA. Nevertheless, the mucosal elevation capacity of PPL solutions for up to 0.7% concentration was similar to that of 0.4% SH, and 0.7% PPL was less resistant to catheter infusion than 0.4% SH and 0.6% SA. In live pig experiments with endoscopic mucosal resection and ESD, snaring after submucosal injection of 0.7% PPL was easier than with 0.4% SH, ESD with 0.7% PPL produced less bubble formation than with 0.4% SH, and the procedure time tended to be shorter with 0.7% PPL than with 0.4% SH because of the shorter injection time. CONCLUSIONS: The PPL solution is an innovative and easy-to-use submucosal injection solution.

Virtual indigo carmine chromoendoscopy images: a novel modality for peroral cholangioscopy using artificial intelligence technology (with video).

BACKGROUND AND AIMS: Accurately diagnosing biliary strictures is crucial for surgical decisions, and although peroral cholangioscopy (POCS) aids in visual diagnosis, diagnosing malignancies or determining lesion margins via this route remains challenging. Indigo carmine is commonly used to evaluate lesions during GI endoscopy. We aimed to establish the utility of virtual indigo carmine chromoendoscopy (VICI) converted from POCS images using artificial intelligence. METHODS: This single-center, retrospective study analyzed 40 patients with biliary strictures who underwent POCS using white-light imaging (WLI) and narrow-band imaging (NBI). A cycle-consistent adversarial network was used to convert the WLI into VICI of POCS images. Three experienced endoscopists evaluated WLI, NBI, and VICI via POCS in all patients. The primary outcome was the visualization quality of surface structures, surface microvessels, and lesion margins. The secondary outcome was diagnostic accuracy. RESULTS: VICI showed superior visualization of the surface structures and lesion margins compared with WLI (P < .001) and NBI (P < .001). The diagnostic accuracies were 72.5%, 87.5%, and 90.0% in WLI alone, WLI and VICI simultaneously, and WLI and NBI simultaneously, respectively. WLI and VICI simultaneously tended to result in higher accuracy than WLI alone (P = .083), and the results were not significantly different from WLI and NBI simultaneously (P = .65). CONCLUSIONS: VICI in POCS proved valuable for visualizing surface structures and lesion margins and contributed to higher diagnostic accuracy comparable to NBI. In addition to NBI, VICI may be a novel supportive modality for POCS.

Long-term Survival After Endoscopic Resection For Gastric Cancer: Real-world Evidence From a Multicenter Prospective Cohort.

BACKGROUND & AIMS: We aimed to clarify the long-term outcomes of endoscopic resection (ER) for early gastric cancers (EGCs) based on pathological curability in a multicenter prospective cohort study. METHODS: We analyzed the long-term outcomes of 9054 patients with 10,021 EGCs undergoing ER between July 2010 and June 2012. Primary endpoint was the 5-year overall survival (OS). The hazard ratio for all-cause mortality was calculated using the Cox proportional hazards model. We also compared the 5-year OS with the expected one calculated for the surgically resected patients with EGC. If the lower limit of the 95% confidence interval (CI) of the 5-year OS exceeded the expected 5-year OS minus a margin of 5% (threshold 5-year OS), ER was considered to be effective. Pathological curability was categorized into en bloc resection, negative margins, and negative lymphovascular invasion: differentiated-type, pT1a, ulcer negative, ≤2 cm (Category A1); differentiated-type, pT1a, ulcer negative, >2 cm or ulcer positive, ≤3 cm (Category A2); undifferentiated-type, pT1a, ulcer negative, ≤2 cm (Category A3); differentiated-type, pT1b (SM1), ≤3 cm (Category B); or noncurative resections (Category C). RESULTS: Overall, the 5-year OS was 89.0% (95% CI, 88.3%-89.6%). In a multivariate analysis, no significant differences were observed when the hazard ratio of Categories A2, A3, and B were compared with that of A1. In all the pathological curability categories, the lower limit of the 95% CI for the 5-year OS exceeded the threshold 5-year OS. CONCLUSION: ER can be recommended as a standard treatment for patients with EGCs fulfilling Category A2, A3, and B, as well as A1 (UMIN Clinical Trial Registry, UMIN000005871).

Efficacy and Safety of a Novel Hemostatic Peptide Solution During Endoscopic Submucosal Dissection: A Multicenter Randomized Controlled Trial.

INTRODUCTION: To compare the effectiveness of the novel hemostatic peptide, TDM-621, with that of conventional hemostatic methods in treating intraoperative blood oozing during endoscopic submucosal dissection (ESD). METHODS: This multicenter, open-label, randomized controlled trial involved 227 patients with gastric and rectal epithelial tumors in whom ESD was indicated. Patients in whom the source of blood oozing was difficult to identify with waterjet washing during the procedure and required hemostasis with hemostatic forceps were randomly assigned to the TDM-621 and control groups. The TDM-621 group (in which hemostasis was achieved with TDM-621, followed by coagulation hemostasis with hemostatic forceps, as needed) was compared with the control group (in which hemostasis was achieved with hemostatic forceps). The primary end point was the mean number of coagulations with hemostatic forceps, determined by a blinded independent review committee. The secondary end points were the rate of achievement of hemostasis with only TDM-621, the dosage of TDM-621, and adverse events in the TDM-621 group. RESULTS: The mean number of coagulations with hemostatic forceps was significantly reduced in the TDM-621 group (1.0 ± 1.4) compared with that in the control group (4.9 ± 5.2) ( P < 0.001). The rate of hemostasis achievement with only TDM-621 was 62.2%; the mean dosage of TDM-621 was 1.75 ± 2.14 mL. The rates of grade ≥3 adverse events were 6.2% and 5.0% in the TDM-621 and control groups, respectively. DISCUSSION: TDM-621 is a useful, easily operable hemostatic peptide for treatment of blood oozing during gastric and rectal ESD, with no serious safety concerns.

Metachronous primary gastric cancer after endoscopic resection in patients with esophageal squamous cell carcinoma.

BACKGROUND: This study aimed to evaluate the risk factors for developing metachronous primary Gastric Cancer (GC) after Endoscopic Resection (ER) for esophageal Squamous Cell Carcinoma (SCC). METHODS: We studied 283 patients with esophageal SCC who underwent ER. The study outcomes were as follows: (1) incidence of metachronous primary GC after ER; and (2) predictors for the development of metachronous primary GC after ER by the Cox proportional hazards model. RESULTS: The median follow-up was 43.1 months (1.81-79.1), and the 3-year cumulative incidence of metachronous primary GC was 6.5% (95%CI: 4.1-10.4). The incidence of metachronous primary GC during the follow-up period was 2.31 per 100 person-years. The frequencies of severe gastric atrophy and macrocytosis at the timing of ER were significantly higher in patients with than without metachronous primary GC (91.7% vs. 73.2%, p = 0.0422, 20.8% vs. 5.2%, p = 0.0046, respectively). Severe gastric atrophy was associated with the development of metachronous primary GC (sex-and-age adjusted hazard ratio (HR) [95%CI] = 4.12 [0.95-27.78], p = 0.0093). Macrocytosis was associated with the development of metachronous primary GC (sex-and-age adjusted HR = 4.76 [1.75-13.0], p = 0.0012) and found to be an independent predictor for metachronous primary GC by multivariate Cox proportional hazards analysis (HR [95%CI] = 4.35 [1.60-11.84], p = 0.004). CONCLUSIONS: Severe gastric atrophy and macrocytosis should be noted in the development of metachronous primary GC after ER for esophageal SCC. In particular, macrocytosis at the timing of ER was considered an important predictor. CLINICAL TRIALS REGISTRY NUMBER: UMIN000001676.

Endoscopic features of gastric neuroendocrine carcinoma.

BACKGROUND AND AIM: The endoscopic features of gastric neuroendocrine carcinoma (G-NEC) have not been clarified; therefore, they were investigated in relation to clinicopathological findings. METHODS: Consecutive patients with G-NECs who had undergone endoscopic or surgical resection at our institution between January 2005 and March 2022 were included in this retrospective study. The endoscopic and clinicopathological findings of the lesions were analyzed to provide information of diagnostic value. In addition, cases of gastric neuroendocrine tumor (G-NET) and common-type gastric adenocarcinoma treated in the same study period were identified to compare the endoscopic findings between each G-NEC versus G-NET, and G-NEC versus common-type gastric adenocarcinoma. Patients with common-type gastric adenocarcinoma were matched for age, sex, tumor size, and depth of tumor invasion in 1:3 ratio. RESULTS: Among 15 patients with 15 G-NECs, submucosal tumor-like marginal elevation (87%), adherent white coat (67%), and ulceration with a distinct border (60%) were characteristic endoscopic findings in white-light images. Magnifying narrow-band imaging endoscopy revealed an absent microsurface (MS) pattern plus disrupted irregular microvessel (MV) in five (71%) of seven cases with evaluable MS and MV patterns. The area with an absent MS pattern plus disrupted irregular MV corresponded to the histological finding of NEC component in all five cases. These endoscopic features were all significantly more frequent in G-NECs than G-NETs (n = 22) or common-type gastric adenocarcinomas (n = 45). CONCLUSIONS: These endoscopic features should be taken into consideration to increase the index of suspicion and to improve the accuracy of target biopsies for G-NEC.

Risk factors for the development of second primary esophageal squamous-cell carcinoma after endoscopic resection for esophageal squamous-cell carcinoma according to genetic polymorphisms related to alcohol and nicotine metabolism.

BACKGROUND: Multiple development of esophageal squamous-cell carcinoma is explained by field cancerization and is associated with alcohol consumption and smoking. We investigated the association between the development of second primary esophageal squamous-cell carcinoma after endoscopic resection for esophageal squamous-cell carcinoma and genetic polymorphisms related to alcohol and nicotine metabolism. METHODS: The study group comprised 56 patients with esophageal squamous-cell carcinoma after endoscopic resection. The main variables were the following: (i) cumulative incidence and total number of second primary esophageal squamous-cell carcinoma according to genetic polymorphisms in alcohol dehydrogenase 1B, aldehyde dehydrogenase 2 and cytochrome P450 2A6; and (ii) risk factors of second primary esophageal squamous-cell carcinoma identified using a multivariate Cox proportional-hazards model. The frequencies of alcohol dehydrogenase 1B, aldehyde dehydrogenase 2 and cytochrome P450 2A6 genetic polymorphisms in the buccal mucosa were analyzed. RESULTS: The median follow-up was 92.8 months (range: 2.7-134.2). Slow-metabolizing alcohol dehydrogenase 1B was associated with a higher 7-year cumulative incidence of second primary esophageal squamous-cell carcinoma (fast-metabolizing alcohol dehydrogenase 1B vs slow-metabolizing alcohol dehydrogenase 1B: 20.5% vs 71.4%, P = 0.006). Slow-metabolizing alcohol dehydrogenase 1B (relative risk [95% confidence interval]: 3.17 [1.49-6.73]), inactive aldehyde dehydrogenase 2 (2.17 [1.01-4.63]) and poorly-metabolizing cytochrome P450 2A6 (4.63 [1.74-12.33]) had a significantly higher total number of second primary esophageal squamous-cell carcinoma per 100 person-years. In the multivariate Cox proportional-hazards model, slow-metabolizing alcohol dehydrogenase 1B was a significant risk factor of the development of second primary esophageal squamous-cell carcinoma (hazard ratio 9.92, 95% confidence interval: 2.35-41.98, P = 0.0018). CONCLUSIONS: Slow-metabolizing alcohol dehydrogenase 1B may be a significant risk factor for the development of second primary esophageal squamous-cell carcinoma. In addition, inactive aldehyde dehydrogenase 2 and poorly-metabolizing cytochrome P450 2A6 may be important factors.

Scattered Tiny Whitish Protrusions in the Stomach Are a Clue to the Diagnosis of Autoimmune Gastritis.

Herein, we report two patients with autoimmune gastritis who had undergone multiple esophagogastroduodenoscopy procedures for 17 and 9 years, respectively, before their diagnosis. Instead, they had been diagnosed with and treated for Helicobacter pylori-associated gastritis. The correct diagnosis was made when scatterings of tiny whitish protrusions in the gastric mucosa were detected on esophagogastroduodenoscopy. Our findings suggest that scattered tiny whitish bumps may be a clue to the diagnosis of autoimmune gastritis.

Characterization of Gastric Tissue-Resident T Cells in Autoimmune and Helicobacter pylori-Associated Gastritis.

Data regarding the in-depth surface marker profiles of gastric tissue-resident lymphocytes in autoimmune and Helicobacter pylori-associated gastritis are lacking. In this study, we investigated potential differences in lymphocyte composition between these profiles. We enrolled patients with autoimmune (n = 14), active (current infection of H. pylori in the stomach; n = 10), and inactive gastritis (post-eradication of H. pylori; n = 20). Lymphocytes were isolated from the greater curvature of the stomach and lesser curvature of the body and analyzed using flow cytometry. The CD8+/CD3+ and CD4+/CD3+ ratios differed between the samples. Body CD4+/antrum CD4+, which is calculated by dividing the CD4+/CD3+ ratio in the body by that in the antrum, was significantly higher in autoimmune gastritis (3.54 ± 3.13) than in active (1.47 ± 0.41) and inactive gastritis (1.42 ± 0.77). Antrum CD8+/CD4+ in autoimmune gastritis (7.86 ± 7.23) was also higher than that in active (1.49 ± 0.58) and inactive gastritis (2.84 ± 2.17). The area under the receiver operating characteristic curve of antrum CD8+/CD4+ was 0.842, and the corresponding optimal cutoff point was 4.0, with a sensitivity of 71.4% and a specificity of 93.3%. We propose that an antrum CD8+/CD4+ ratio > 4.0 is a potential diagnostic marker for autoimmune gastritis.

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.

The diagnostic ability to classify neoplasias occurring in inflammatory bowel disease by artificial intelligence and endoscopists: A pilot study.

BACKGROUND AND AIM: Although endoscopic resection with careful surveillance instead of total proctocolectomy become to be permitted for visible low-grade dysplasia, it is unclear how accurately endoscopists can differentiate these lesions, as classifying neoplasias occurring in inflammatory bowel disease (IBDN) is exceedingly challenging due to background chronic inflammation. We evaluated a pilot model of an artificial intelligence (AI) system for classifying IBDN and compared it with the endoscopist's ability. METHODS: This study used a deep convolutional neural network, the EfficientNet-B3. Among patients who underwent treatment for IBDN at two hospitals between 2003 and 2021, we selected 862 non-magnified endoscopic images from 99 IBDN lesions and utilized 6 375 352 images that were increased by data augmentation for the development of AI. We evaluated the diagnostic ability of AI using two classifications: the "adenocarcinoma/high-grade dysplasia" and "low-grade dysplasia/sporadic adenoma/normal mucosa" groups. We compared the diagnostic accuracy between AI and endoscopists (three non-experts and four experts) using 186 test set images. RESULTS: The diagnostic ability of the experts/non-experts/AI for the two classifications in the test set images had a sensitivity of 60.5% (95% confidence interval [CI]: 54.5-66.3)/70.5% (95% CI: 63.8-76.6)/72.5% (95% CI: 60.4-82.5), specificity of 88.0% (95% CI: 84.7-90.8)/78.8% (95% CI: 74.3-83.1)/82.9% (95% CI: 74.8-89.2), and accuracy of 77.8% (95% CI: 74.7-80.8)/75.8% (95% CI: 72-79.3)/79.0% (95% CI: 72.5-84.6), respectively. CONCLUSIONS: The diagnostic accuracy of the two classifications of IBDN was higher than that of the experts. Our AI system is valuable enough to contribute to the next generation of clinical practice.

Linked Color Imaging (LCI) Emphasizes the Color Changes in the Gastric Mucosa After Helicobacter pylori Eradication.

BACKGROUND: Diffuse redness is a characteristic endoscopic finding that indicates current infection of Helicobacter pylori, which is reduced after successful eradication. Linked color imaging (LCI) has been reported to improve the visibility of diffuse redness compared to white light imaging (WLI); however, quantitative evaluation has not been reported. AIMS: This study aimed to objectively evaluate the color change of the gastric mucosa after H. pylori eradication. METHODS: Images of the greater curvature of the antrum and corpus were captured, and the sites were biopsied during esophagogastroduodenoscopy (EGD) before and 1 year after eradication. The region of interest (ROI) was set around the biopsied area on the images. The color difference (ΔE) before and after eradication was calculated using the CIE L*a*b* color space. The association between the histological evaluation and the color value of the corresponding ROI was determined. RESULTS: At the antrum, there was no significant color change with either mode. At the corpus, the a* value, which reflected redness, decreased significantly after eradication with both modes (WLI: 41.2 to 36.0, LCI: 37.5 to 25.5); the b* value, reflecting yellowish, decreased with WLI, but increased significantly with LCI (WLI: 44.6 to 41.6, LCI: 23.9 to 29.2). The ΔE was significantly larger with LCI than with WLI (16.5 vs. 8.6). The a* values at the corpus were generally associated with histological neutrophil infiltration. CONCLUSIONS: Quantitative evaluation revealed that LCI emphasizes the change in color of the gastric mucosa due to the reduction in diffuse redness.

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.

[Zinc acetate-associated gastric lesions:a case report].

An 82-year-old Japanese man underwent esophagogastroduodenoscopy for postprandial epigastric discomfort. The patient was diagnosed with hypozincemia with a serum zinc level of 63µg/dL (normal range:80-130µg/dL), and he had commenced oral intake of zinc acetate 1 month before the esophagogastroduodenoscopy. Endoscopy showed erosions with white-coated mucosa surface adhesions and erythema on the lesser curvature of the gastric body. Moderately differentiated tubular adenocarcinoma was suspected based on the biopsy examination findings;therefore, he was referred to our hospital for further examination and treatment. A repeat endoscopy showed two erosions with white-coated mucosa surface adhesion and erythema on the lesser curvature of the gastric body. However, the lesion location was different from that detected in the initial endoscopy. The biopsy showed no neoplastic changes. Therefore, based on the endoscopic findings and history of oral zinc acetate administration, we diagnosed the gastric mucosal injury as zinc acetate-associated gastric lesions. The cessation of zinc acetate intake resulted in the resolution of gastric lesions. Reassessment of the biopsy specimen from the initial endoscopy revealed erosions, epithelial cells showing infarct-like necrosis, degenerative atypical cells, and necrotic substances, which were misdiagnosed as neoplastic changes. This case highlights the importance of recognizing the typical endoscopic features of a zinc acetate-associated gastric lesion to enable its prompt diagnosis during esophagogastroduodenoscopy.

Gastric Adenoma: A High Incidence Rate of Developing Carcinoma and Risk of Metachronous Gastric Cancer according to Long-Term Follow-Up.

INTRODUCTION: Gastric adenomas are histologically defined as benign epithelial tumors. While some of them remain adenomas for a long time, others progress to carcinomas. However, long-term outcomes of such cases are not entirely clear. Here, we explored the risk factors and incidence of developing carcinoma from gastric adenoma as well as metachronous gastric cancer. METHODS: This study was conducted at a facility that adopted a follow-up strategy for gastric adenoma. Lesions histologically diagnosed as gastric intestinal-type adenomas between January 2004 and December 2016 were analyzed. Clinicopathological data were collected from patients' medical records, and histological changes from adenoma to carcinoma during endoscopic follow-up and risk factors of cancer development were evaluated. RESULTS: This study involved 409 lesions from 376 patients. The analysis of the development of gastric cancer from adenoma and metachronous gastric cancer was ultimately performed for 282 lesions from 258 patients and 269 lesions from 246 patients, respectively, due to different follow-up periods. The 5-year rate of carcinoma development was 34.0%. Risk factors for carcinoma development upon multivariate analysis were lesion size ≥15 mm and morphological depression. All cases with both factors developed gastric carcinoma, and 50.5% of those with either factor developed carcinoma within 5 years. Gastric adenoma was accompanied by metachronous gastric cancer in 1.5% of the patients annually. The only risk factor for metachronous gastric carcinoma was primary adenoma progressing to carcinoma during the follow-up period. DISCUSSION/CONCLUSION: Given the high rate of carcinoma development in patients with risk factors, resection of gastric adenoma should be considered during the initial examination. Careful observation and follow-up should also be conducted to detect not only changes in the primary adenoma but also the occurrence of metachronous carcinoma, especially in cases of adenoma progressing to carcinoma.

Histologic Transformation from Follicular Lymphoma to Diffuse Large B-cell Lymphoma Detected during Colonoscopy.

A 77-year-old Japanese woman who had been treated for follicular lymphoma for 8 years developed abdominal pain and intra-abdominal lymphadenopathies. Colonoscopy revealed an elevated lesion in the rectum, which presented as two humps with erosions. A diagnosis of histologic transformation of follicular lymphoma to diffuse large B-cell lymphoma was made by endoscopic biopsy. This case underscores the importance of endoscopy examinations and biopsy of newly emerged gastrointestinal lesions for the prompt diagnosis of histologic transformation, since salvage chemotherapy must be initiated quickly in such cases.

[Clinical characteristics of five patients with gastric emphysema].

Gastric emphysema is a rare condition in which gas from a nonbacterial source accumulates within the gastric wall. In this study, we retrospectively analyzed the cases of five patients who were diagnosed with gastric emphysema at the Okayama University Hospital between January 2010 and April 2021, to reveal the clinical features of the disease. Based on their reviews, we revealed that:i) gastric emphysema occurred in hospitalized bedridden patients (n=5), such as those during/after endotracheal intubation (n=3), those undergoing gastric tube placement (n=3), those undergoing percutaneous endoscopic gastrostomy (n=1), and those undergoing treatment for cerebral infarction (n=1);ii) gastric emphysema was accompanied by the accumulation of gas in the portal (n=4) or gastric veins (n=1);iii) gastric emphysema was accompanied by colon wall thickness increase (n=4);iv) esophagogastroduodenoscopy showed redness, erosions, coarse mucosa, and/or ulcers (n=5);v) a clear boundary between the damaged area and the intact mucosa was observed (n=5);vi) the anterior wall of the stomach was less affected (n=4);vii) mucosal damage was predominant in the gastric folds, whereas the furrow of the mucosa was less affected;and viii) treatment with enteral nutrition suspension and the administration of proton pump inhibitors and antibiotics resulted in the recovery of patients from gastric emphysema (n=5). These results indicate that patients with gastric emphysema have distinct clinical, endoscopic, and radiological features. Furthermore, our results show that these patients can be conservatively managed.

Long-term outcomes of endoscopic versus surgical resection for MM-SM1 esophageal squamous cell carcinoma using propensity score analysis.

BACKGROUND: Esophageal squamous cell carcinoma (ESCC) confined to the muscularis mucosae (MM) or up to 200 µm of the submucosa (SM1) confers the risk for lymph node metastasis, and is defined as relative indication for endoscopic submucosal dissection (ESD) by the Japan Esophageal Society guidelines. Although additional surgical treatment after ESD is recommended, long-term outcomes of ESD compared with those of surgery have not been clarified. This study aimed to evaluate the long-term outcomes of ESD and surgery for cN0M0 relative indication lesions of ESCC. METHODS: Between 2006 and 2016, patients with relative indication lesions of ESCC who underwent ESD or surgery at nine participating hospitals were examined retrospectively. Using propensity score matching, we evaluated survival curves for and hazard ratios associated with endoscopic submucosal dissection and surgery. RESULTS: In total, 155 lesions in the ESD group and 106 lesions in the surgery group met the pathological criteria of relative indication for endoscopic resection. After matching, 50 matched pairs of patients who underwent ESD or surgery were selected. The 5-year overall survival rates were 84.5% [95% confidence interval (CI) 68-93] in the ESD group and 79% [95% CI 60-90] in the surgery group. The hazard ratio of mortality for ESD compared with that for surgery estimated by Cox regression analysis was 0.79 (95% CI 0.3-2.06, p = 0.63). CONCLUSIONS: Compared with surgery, ESD does not compromise long-term outcomes. ESD alone or ESD with chemotherapy and/or radiotherapy may be an option for the treatment of MM and SM1 ESCC.

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.).

The Color Difference between Differentiated Early Gastric Cancer and Suspicious Mucosal Areas on Linked Color Imaging.

BACKGROUND: Image enhanced endoscopy (IEE) contributes to the early detection of gastrointestinal cancer. IEE enhances the color between a lesion and the background mucosa. Linked color imaging (LCI), a novel form of IEE, is a unique system for enhancing color and some studies have demonstrated the efficacy of LCI in the diagnosis of early gastric cancer (EGC) based on the color difference between cancer and the background mucosa. However, the effect may increase the area in which cancer is suspected and lead to an increase in false-positive results. SUMMARY: We conducted a retrospective study of linked color images of differentiated EGC and suspicious mucosal areas to compare the colors between each lesion. Images of 38 EGCs and 23 suspicious areas were analyzed. The mean color values of EGC were as follows; L*(lightness), 61.7; a*(green to red), 41.2; and b*(blue to yellow), 27.1. Those of suspicious mucosal areas were as follows; L*, 56.1; a*, 44.2; and b*, 21.3. EGC had significantly higher L*, b* values and lower a* values in comparison to suspicious mucosal areas. EGC and suspicious mucosal areas had significantly higher a* values in comparison to the background mucosa. Key Messages: EGC had higher b* values in comparison to suspicious mucosal areas, and was not only reddish but also mixed with yellow, with an orange-like color.