Feasibility of Colorectal Endoscopic Submucosal Dissection in Elderly Patients: The Impact of Sarcopenia.

INTRODUCTION: Colorectal cancer is a public health concern associated with high incidence rates. Sarcopenia is a known risk factor for postoperative complications, although an association between increased complications after colorectal endoscopic submucosal dissection (ESD) and sarcopenia remains undocumented. Herein, we aimed to explore the feasibility of colorectal ESD in patients with sarcopenia. METHODS: This retrospective study included 499 patients (69 with and 430 without sarcopenia). We evaluated the short- and long-term outcomes of colorectal ESD. RESULTS: There were no significant differences between the two groups regarding en bloc, R0, or curative resection rates. However, poor bowel preparation was significantly more common in the sarcopenia group. Moreover, patients with sarcopenia exhibited a significant increase in complications (37.7% vs. 10.5%). Multivariate analysis revealed that sarcopenia (odds ratio [OR]: 3.78, 95% confidence interval [Cl]: 1.85-7.73, p < 0.001), anticoagulation therapy (OR: 3.59, 95% Cl: 1.86-6.92, p < 0.001), procedure time (OR: 1.28, 95% Cl: 1.11-1.47, p < 0.001), and resection size (OR: 1.25, 95% Cl: 1.03-1.52, p = 0.02) were significantly correlated with the Common Terminology Criteria for Adverse Events (CTCAE) ≥ grade 2. The correlation between sarcopenia and CTCAE ≥ grade 2 was maintained after matching, resulting in more extended hospital stays in patients with sarcopenia. However, we detected no association between sarcopenia and overall survival and ESD-related death. CONCLUSION: Sarcopenia is a risk factor for complications in colorectal ESD, suggesting that colorectal ESD could be performed for patients with sarcopenia, although much caution should be taken.

Endoscopist-related factors affecting adenoma detection during colonoscopy: Data from the J-SCOUT study.

OBJECTIVES: Colonoscopy withdrawal times are associated with the adenoma detection rate (ADR). However, the relationship between ADR and cecal insertion time has been inadequately characterized. We aimed to evaluate endoscopist-related factors involved in the ADR, including the average individual colonoscopy insertion and withdrawal times. METHODS: This observational study used a colonoscopy database with pathology data from routine clinical practice in Japanese institutions. The odds ratios (OR) of endoscopist-related factors related to ADRs were examined using a generalized linear mixed model. RESULTS: Of the 186,293 colonoscopies performed during the study period, 47,705 colonoscopies by 189 endoscopists in four hospitals were analyzed for ADR. The overall ADR was 38.3% (95% confidence interval [CI] 37.8, 38.7). Compared to endoscopists with mean cecal insertion times of <5 min, the OR of ADR for those with mean cecal insertion times of 5-9, 10-14, and ≥15 min were 0.84 (95% CI 0.71, 0.99), 0.68 (95% CI 0.52, 0.90), and 0.45 (95% CI 0.25, 0.78), respectively. Compared to endoscopists with mean withdrawal times of <6 min, the OR of ADR for those with mean withdrawal times of 6-9, 10-14, and ≥15 min were 1.38 (95% CI 1.03, 1.85), 1.48 (95% CI 1.09, 2.02), and 1.68 (95% CI 1.04, 2.61), respectively. There were no significant differences in ADRs by endoscopist specialty, gender, or the total number of examinations performed. CONCLUSION: Individual mean colonoscopy insertion time was associated with ADR and might be considered as a colonoscopy quality indicator as well as withdrawal time.

Transcriptome analysis reveals the essential role of NK2 homeobox 1/thyroid transcription factor 1 (NKX2-1/TTF-1) in gastric adenocarcinoma of fundic-gland type.

BACKGROUND: Gastric adenocarcinoma of fundic-gland type (GA-FG) is a gastric malignancy with little relation to Helicobacter pylori. Clinical characteristics of GA-FG have been established, but molecular mechanisms leading to tumorigenesis have not yet been elucidated. METHODS: We subjected three GA-FG tumors-normal mucosa pairs to microarray analysis. Network analysis was performed for the top 30 up-regulated gene transcripts, followed by immunohistochemical staining to confirm the gene expression analysis results. AGS and NUGC4 cells were transfected with the gene-encoding NK2 homeobox 1/thyroid transcription factor 1 (NKX2-1/TTF-1) to evaluate transcriptional changes in its target genes. RESULTS: Comprehensive gene expression analysis identified 1410 up-regulated and 1395 down-regulated gene probes with ≥ two-fold difference in expression. Among the top 30 up-regulated genes in GA-FG, we identified transcription factor NKX2-1/TTF-1, a master regulator of lung/thyroid differentiation, together with surfactant protein B (SFTPB), SFTPC, and secretoglobin family 3A member 2(SCGB3A2), which are regulated by NKX2-1/TTF-1. Immunohistochemical analysis of 16 GA-FG specimens demonstrated significantly higher NKX2-1/TTF-1 and SFTPB levels, as compared to that in adjacent normal mucosa (P < 0.05), while SCGB3A2 levels did not differ (P = 0.341). Transduction of NKX2-1/TTF-1 into AGS and NUGC4 cells induced transactivation of SFTPB and SFTPC, indicating that NKX2-1/TTF-1 can function as normally in gastric cells as it can in the lung cells. CONCLUSIONS: Our first transcriptome analysis of GA-FG indicates significant expression of NKX2-1/TTF1 in GA-FG. Immunohistochemistry and cell biology show ectopic expression and normal transactivation ability of NKX2-1/TTF-1, suggesting that it plays an essential role in GA-FG development.

Reduced DEFA5 Expression and STAT3 Activation Underlie the Submucosal Invasion of Early Gastric Cancers.

INTRODUCTION: Submucosal invasion is a core hallmark of early gastric cancer (EGC) with poor prognosis. However, the molecular mechanism of the progression from intramucosal gastric cancer (IMGC) to early submucosal-invasive gastric cancer (SMGC) is not fully understood. The objective of this study was to identify genes and pathways involved in the submucosal invasion in EGC using comprehensive gene expression analysis. METHODS: Gene expression profiling was performed for eight cases of IMGC and eight cases of early SMGC with submucosal invasion ≥500 µm. To validate the findings of gene expression analysis and to examine the gene expression pattern in tissues, immunohistochemical (IHC) staining was performed for 50 cases of IMGC and SMGC each. RESULTS: Gene expression analysis demonstrated that the expression levels of small intestine-specific genes were significantly decreased in SMGC. Among them, defensin alpha 5 (DEFA5) was the most downregulated gene in SMGC, which was further validated in SMGC tissues by IHC staining. Gene set enrichment analysis showed a strong association between SMGC, the JAK-STAT signaling pathway, and the upregulation of STAT3-activating cytokines. The expression of phosphorylated STAT3 was significant in the nucleus of tumor cells in SMGC tissues but not in areas expressing DEFA5. CONCLUSION: The results of this study strongly suggest that the downregulation of DEFA5 and the activation of STAT3 play a significant role in the submucosal invasion of EGC.

Risk factors for incomplete resection with pharyngeal endoscopic submucosal dissection and long-term prognosis after resection.

BACKGROUND: Advances in endoscopic imaging technology have led to an increase in detection of superficial pharyngeal squamous carcinoma. Endoscopic submucosal dissection (ESD) has been reported to be effective for the treatment of these lesions, however there is still insufficient evidence on the long-term results of pharyngeal ESD. METHODS: This is a single-center retrospective study of all cases of superficial pharyngeal cancer that underwent ESD as primary treatment between January 2010 and May 2022. A total of 83 lesions in 63 patients were analyzed. RESULTS: The en bloc resection rate was 100%, and R0 resection rate was 59.0%, with an adverse event rate of 6.0%. During a mean observation period of 1134 days, there were 0 cases of disease-specific metastasis or death. However, the 5-year cumulative incidence of metachronous head and neck cancer after resection was 27.1% and the 5-year overall survival and 10-year overall survival after pharyngeal ESD were 87.0% and 69.6%, respectively. Of the 34 cases with non-R0 resection, local recurrence occurred in 8.8%. Location of lesion (p = 0.011), disparity between demarcation of the lesion with NBI and iodine staining (p = 0.026), and non-effective laryngeal elevation (p = 0.080) were risk factors for non-R0 resection. CONCLUSION: Pharyngeal ESD is effective and safe. Further studies are needed to improve and standardize indications and strategies for pharyngeal ESD.

Repeated steroid injection and polyglycolic acid shielding for prevention of refractory esophageal stricture.

BACKGROUND: Postoperative stricture and refractory stricture are severe adverse events which occur after expansive esophageal endoscopic submucosal dissection (ESD). The aim of this study was to assess the efficacy of steroid injection, polyglycolic acid (PGA) shielding, and of additional steroid injection thereafter for the prevention of refractory esophageal stricture. METHODS: This is a retrospective cohort study of 816 consecutive cases of esophageal ESD performed between 2002 and 2021 at the University of Tokyo Hospital. After 2013, all patients with a diagnosis of superficial esophageal carcinoma covering over 1/2 the esophageal circumference underwent preventive treatment immediately after ESD with either "PGA shielding", "steroid injection", or "steroid injection + PGA shielding". Additional steroid injection was performed for high-risk patients after 2019. RESULTS: The risk of refractory stricture was especially high in the cervical esophagus (OR 24.77, p = 0.002) and after total circumferential resection (OR 894.04, p < 0.001). "Steroid injection + PGA shielding" was the only method significantly effective in preventing stricture occurrence (OR 0.36; 95% CI 0.15-0.83, p = 0.012). This method also decreased the risk of refractory stricture (OR 0.38; 95% CI 0.10-1.28, p = 0.096), but additional steroid injection was the only significantly effective method for prevention of refractory stricture (OR 0.42; 95% CI 0.14-0.98, p = 0.029). CONCLUSION: Combining steroid injection and PGA shielding is effective for preventing post-ESD stricture and refractory stricture. Additional steroid injection is a viable option for patients at high-risk for refractory stricture.

"Endoscopic" adenoma detection rate as a quality indicator of colonoscopy: First report from the J-SCOUT study.

OBJECTIVES: To examine whether reasonable detection rate of endoscopically diagnosed lesions as adenoma ("endoscopic" adenoma detection rate [ADR]) could be calculated with a database generated from colonoscopy reports and whether it could be used as a surrogate colonoscopy quality indicator of "pathological" ADR. METHODS: A lesion-by-lesion database of colonoscopies performed between 2010 and 2020 at eight Japanese endoscopy centers and corresponding pathology database were integrated. Differences in numbers of detected polyps, "endoscopic" and "pathological" adenomas, and what these differences could be attributed to were examined. Polyp detection rate (PDR), "endoscopic" and "pathological" ADRs, and correlation coefficients between "pathological" ADR and PDR or "endoscopic" ADR by each endoscopist were calculated. RESULTS: Overall, 129,065 colonoscopy reports were analyzed. Among a total of 146,854 polyps, more "endoscopic" adenomas (n = 117,359) were observed than "pathological" adenomas (n = 70,076), primarily because adenomas were not resected on site, rather than because of a misdiagnosis. In all patients analyzed, PDR, "endoscopic" and "pathological" ADRs were 56.4% (95% confidence interval [CI] 56.2-56.7), 48.0% (95% CI 47.7-48.3), and 32.7% (95% CI 32.5-33.0), respectively. "Endoscopic" and "pathological" ADRs from each endoscopist showed a high correlation in hospitals where adenomas were usually resected at the time of examination. CONCLUSIONS: By appropriately describing endoscopically diagnosed lesions as "adenomas" in endoscopy reports, "endoscopic" ADR might be used as a surrogate colonoscopy quality indicator of "pathological" ADR (UMIN000040690).

Analysis of Barrett's Esophagus and Its Risk Factors: A Cross-Sectional Study of 10,122 Subjects at a Japanese Health Examination Center.

INTRODUCTION: Helicobacter pylori eradication is expected to significantly change the prevalence of Barrett's esophagus (BE). However, few reports on this relationship exist. We analyzed the risk factors of BE using the current consensus on length of BE considering H. pylori infection status. METHODS: We analyzed 10,122 individuals (5,962 men; mean age = 52.9 ± 9.9 years) who had undergone esophagogastroduodenoscopy as part of a medical checkup. Correlations among factors including H. pylori infectious status, endoscopic findings, and BE ≥1 cm were analyzed. RESULTS: Prevalence of BE, long-segment BE, and esophageal adenocarcinoma was 22.5%, 0.014%, and 0%, respectively. Logistic regression analysis showed that the risk factors for BE were hiatal hernia (odds ratio [OR]: 2.89 [2.59-3.24]), female sex (OR: 0.52 [0.46-0.59]), social drinking (OR:0.77 [0.68-0.87]), H. pylori eradication therapy (OR: 1.34 [1.19-1.51]), proton pump inhibitor (PPI) use (OR: 1.52 [1.18-1.96]), bile reflux (OR: 1.18 [1.04-1.33]), age ≥50 years (OR: 1.13 [1.02-1.26]), and nonsteroidal anti-inflammatory drug (NSAID) use (OR: 1.29 [1.02-1.62]). Although reflux esophagitis (RE) was more common in H. pylori-negative patients (17.2%) than in those after H. pylori eradication therapy (11.8%, p < 0.00001), the latter was correlated with BE, disputing RE as a strong risk factor for BE. Therefore, we conducted a subgroup analysis; most of the risk factors except for PPI use (p = 0.75), H2-receptor antagonist use (p = 0.078), and atrophic gastritis absence (p = 0.72) were positively correlated with BE after H. pylori eradication therapy compared with H. pylori-negative status. CONCLUSIONS: H. pylori eradication, bile reflux, PPI use, and NSAID use were risk factors for BE along with hiatal hernia, male sex, and older age.

The impact of sarcopenia on adverse events associated with gastric endoscopic submucosal dissection.

BACKGROUND: Endoscopic submucosal dissection (ESD) is one of the main methods of treatments for early gastric cancer. Sarcopenia is a known risk factor for postoperative adverse events; however, the effect of sarcopenia on gastric ESD is unclear. We investigated the impact of sarcopenia on short-term prognosis after gastric ESD. METHODS: This was a retrospective cohort study. We reviewed 832 patients who underwent gastric ESD between January 2015 and December 2019 and classified them into two groups: sarcopenia and non-sarcopenia groups. The curative resection rate, adverse events, and lengths of hospital stay were evaluated. We also evaluated risk factors associated with adverse events. RESULTS: 700 patients were analyzed (239 in the sarcopenia group and 461 in the non-sarcopenia group). The curative resection rates were similar in both groups. Common Terminology Criteria for Adverse Events (CTCAE) grade ≥ 2 (17% vs. 10%) were significantly more common, and the length of hospital stay was longer (8 vs. 7 days) in the sarcopenia group. Univariate analysis identified age ≥ 75 years, antithrombotic medication, history of gastric surgery, submucosal (SM) invasion, and sarcopenia as risk factors for CTCAE grade ≥ 2. Multivariate analysis showed that sarcopenia [odds ratio (OR) 1.79, 95% confidence interval (CI) 1.11-2.89, p = 0.016], history of gastric surgery (OR 9.32, 95% CI 1.97-44.05, p = 0.005), and SM invasion (OR 2.14, 95% CI 1.24-3.70, p = 0.006) were significant independent risk factors. CONCLUSIONS: Sarcopenia significantly affected short-term prognosis and is a novel risk factor for gastric ESD.

Clinical usefulness of red dichromatic imaging in hemostatic treatment during endoscopic submucosal dissection: First report from a multicenter, open-label, randomized controlled trial.

OBJECTIVES: To verify the efficacy and safety of red dichromatic imaging (RDI) in hemostatic procedures during endoscopic submucosal dissection (ESD). METHODS: This is a multicenter randomized controlled trial of 404 patients who underwent ESD of the esophagus, stomach, colorectum. Patients who received hemostatic treatments by RDI during ESD were defined as the RDI group (n = 204), and those who received hemostatic treatments by white light imaging (WLI) were defined as the WLI group (n = 200). The primary endpoint was a shortening of the hemostasis time. The secondary endpoints were a reduction of the psychological stress experienced by the endoscopist during the hemostatic treatment, a shortened treatment time, and a non-inferior perforation rate, in RDI versus WLI. RESULTS: The mean hemostasis time in RDI (n = 860) was not significantly shorter than that in WLI (n = 1049) (62.3 ± 108.1 vs. 56.2 ± 74.6 s; P = 0.921). The median hemostasis time was significantly longer in RDI than in WLI (36.0 [18.0-71.0] vs. 28.0 [14.0-66.0] s; P = 0.001) in a sensitivity analysis. The psychological stress was significantly lower in RDI than in WLI (1.71 ± 0.935 vs. 2.03 ± 1.038; P < 0.001). There was no significant difference in the ESD treatment time between RDI (n = 161) and WLI (n = 168) (58.0 [35.0-86.0] vs. 60.0 [38.0-88.5] min; P = 0.855). Four perforations were observed, but none of them took place during the hemostatic treatment. CONCLUSIONS: Hemostatic treatment using RDI does not shorten the hemostasis time. RDI, however, is safe to use for hemostatic procedures and reduces the psychological stress experienced by endoscopists when they perform hemostatic treatment during ESD. UMIN000025134.

Steroid injection and polyglycolic acid shielding to prevent stricture after esophageal endoscopic submucosal dissection: a retrospective comparative analysis (with video).

BACKGROUND AND AIMS: Postoperative stricture after expansive esophageal endoscopic submucosal dissection (ESD) is a severe adverse event. Previous single-arm reports have suggested that polyglycolic acid (PGA) shielding may prevent stricture. This study was performed to assess the efficacy of this method through a comparative analysis. METHODS: This is a retrospective analysis of 500 consecutive cases of esophageal ESD performed between 2002 and 2018 at the University of Tokyo Hospital. After 2013, patients with a diagnosis of superficial esophageal carcinoma covering more than half of the esophageal circumference underwent preventive treatment with either PGA shielding or steroid injection + PGA shielding after ESD. The efficacy of these methods for preventing post-ESD stricture was assessed through multivariable logistic regression analysis. RESULTS: The risk of postoperative stricture was especially high in the cervical esophagus (odds ratio [OR], 4.60; 95% confidence interval [CI], 0.65-61.09) and after total circumferential resection (OR, 3.58×103; lower bound of 95% CI, >185). Steroid injection + PGA shielding was the only method significantly effective in preventing stricture (OR, 0.30; 95% CI, 0.10-0.78; P = .009). In the relatively low-risk subgroup (excluding cervical esophageal cancer and complete circumferential resection), the postoperative stricture rates for steroid injection + PGA shielding versus PGA shielding versus control were 18.9% versus 41.4% versus 51.7%, respectively (P = .015). However, the efficacy of this was limited in extremely high-risk cases. CONCLUSION: The combination of steroid injection and PGA shielding is effective for preventing post-ESD stricture. There is a need for even more effective methods for cervical esophageal cancer and complete circumferential resection.

Early detection of gastric cancer after Helicobacter pylori eradication due to endoscopic surveillance.

BACKGROUND: Helicobacter pylori eradication therapy is commonly performed to reduce the incidence of gastric cancer. However, gastric cancer is occasionally discovered even after successful eradication therapy. Therefore, we examined the prognosis of gastric cancer patients, diagnosed after successful H. pylori eradication therapy. MATERIALS AND METHODS: All-cause death rates and gastric cancer-specific death rates in gastric cancer patients who received successful H. pylori eradication treatment was tracked and compared to rates in patients who did not receive successful eradication therapy. RESULTS: In total, 160 gastric cancer patients were followed-up for up to 11.7 years (mean 3.5 years). Among them, 53 gastric cancer patients received successful H. pylori eradication therapy prior to gastric cancer diagnosis. During the follow-up period, 11 all-cause deaths occurred. In the successful eradication group, the proportion of patients with cancer stage I was higher. The proportions of patients who received curative endoscopic therapy and endoscopic examination in the 2 years prior to gastric cancer diagnosis were also higher in the successful eradication group. Kaplan-Meier analysis of all-cause death and gastric cancer-specific death revealed a lower death rate in patients in the successful eradication group (P = .0139, and P = .0396, respectively, log-rank test). The multivariate analysis showed that endoscopy within 2 years before cancer diagnosis is associated with stage I cancer. CONCLUSIONS: Possible early discovery of gastric cancer after H. pylori eradication due to regular endoscopic surveillance may contribute to better prognosis of patients with gastric cancer.

Pethidine dose and female sex as risk factors for nausea after esophagogastroduodenoscopy.

Nausea and vomiting after esophagogastroduodenoscopy have not been studied in detail. The aim of this study was to evaluate the risk factors for post-endoscopic nausea. We performed a case-control study at the Toyoshima Endoscopy Clinic. Eighteen patients with post-endoscopic nausea and 190 controls without post-endoscopic nausea were analyzed. We conducted univariate and multivariate logistic regression analyses with respect to patient age; sex; body height; body weight; the use of psychotropic drugs as baseline medications; and the dosing amounts of midazolam, pethidine, flumazenil and naloxone. On univariate analysis, post-endoscopic nausea was significantly related with patient age (odds ratio = 0.946); female sex (odds ratio = 10.85); body weight (odds ratio = 0.975); and the dose per kg body weight of pethidine (odds ratio = 53.03), naloxone (odds ratio = 1.676), and flumazenil (odds ratio = 1.26). On multivariate analysis, the dose per kg body weight of pethidine (odds ratio = 21.67, p = 0.004) and female sex (odds ratio = 13.12, p = 0.047) were the factors independently associated with post-endoscopic nausea. The prevalence of nausea after esophagogastroduodenoscopy was 0.49% (18/3,654). In conclusion, post-endoscopic nausea was associated with the dose of pethidine and female sex.

Clinical meaning of sarcopenia in patients undergoing endoscopic treatment.

With increasing global life expectancy, the significance of geriatric assessment parameters has increased. Sarcopenia is a crucial assessment parameter and is defined as the age-related loss of muscle mass and strength. Sarcopenia is widely acknowledged as a risk factor for postoperative complications in diverse advanced malignancies and has a detrimental effect on the long-term prognosis. While most studies have primarily concentrated on the correlation between sarcopenia and advanced cancer, more recent investigations have focused on the relationship between sarcopenia and early-stage cancer. Endoscopic submucosal dissection (ESD), which is less invasive than surgical intervention, is extensively employed in the management of early-stage cancer, although it is associated with complications such as bleeding and perforation. In recent years, several reports have revealed the adverse consequences of sarcopenia in patients with early-stage cancer undergoing ESD. This literature review briefly summarizes the recent studies on the association between sarcopenia and ESD.

Verification of the increase in concomitant dysplasia and cancer with the size of sessile serrated lesions.

Background and study aims This study aimed to evaluate the relationship between sessile serrated lesion (SSL) size and the comorbidity rate of SSL with dysplasia (SSLD) and cancer in SSL (SSL-cancer). Patients and methods This retrospective, single-center analysis identified SSL cases that underwent endoscopic resection between January 2015 and December 2022. The prevalence of SSL, SSLD, and SSL-cancer and their annual trends were assessed. The tumor diameter was stratified as 0 to 5 mm, 6 to 9 mm, 10 to 19 mm, and ≥ 20 mm in size. Furthermore, the frequency of SSL-D/SSL-cancer was determined in each group. Results The prevalence of SSL was 2.9% (1328/45799). This prevalence was 1.8% (112/6192) in 2015 and 4.2% (230/5500) in 2022, indicating an increasing trend over time. A total of 1825 lesions were assessed: 1751 (96.0%), 55 (3.0%), 14 (0.8%), and 5 (0.3%) of lesions were SSL, SSL with low-grade dysplasia, SSL with high-grade dysplasia and SSL-cancer, respectively. Stratifying the SSLs by size: 0 to 5 mm, 5 to 9 mm, 10 to 19 mm, and ≥ 20 mm, SSLD and SSL-cancer rates were 2.3% (10/429), 2.4% (16/674), 5.3% (31/584), and 11.8% (16/136), respectively. SSLD and SSL-cancer were observed in 2.4% (26/1103) of small SSLs < 10 mm. Conclusions In cases of SSL, the rate of SSLD and SSL-cancer increased as the lesion diameter increased. A certain rate of SSLD and SSL-cancer was observed even in small SSLs less than 5mm.

Performing the ABC Method Twice for Gastric Cancer Risk Stratification: A Retrospective Study Based on Data from a Large-Scale Screening Facility.

The ABC method is a classification method used for stratifying the risk of gastric cancer. However, whether the ABC method should be performed only once or multiple times throughout an individual's lifetime remains unclear. Therefore, this study aimed to analyze whether performing ABC screening twice in a lifetime is useful. We retrospectively analyzed the data of individuals who participated in health checkups in 2010 and 2015. We collected data on patient characteristics, pepsinogen levels, anti-Helicobacter pylori antibody titers, and the presence of gastric cancer. Overall, 7129 participants without a history of H. pylori eradication were included in this study. The participants' average age in 2010 was 48.4 ± 8.3 years, and 58.1% were male. In addition, 11 and 20 cases of new H. pylori infection (0.15%) and spontaneous eradication (0.28%), respectively, were recorded. No significant difference was found in the incidence of gastric cancer between participants who underwent the ABC method once and those who underwent it twice (Group A: 0.16% vs. 0.16%; Group B: 0.47% vs. 0.39%; and Group C + D: 1.97% vs. 1.82%). Therefore, performing the ABC method twice, 5 years apart, does not significantly improve gastric cancer risk stratification.

A case of a tiny neuroendocrine carcinoma in a large flat-elevated rectal tumor causing multiple liver metastases.

Neuroendocrine tumors are rare malignancies comprising neuroendocrine cells widely distributed in the human body. They occur in various organs of the body, most commonly in the gastrointestinal tract and pancreas in the Japanese population. Mixed neuroendocrine-non-neuroendocrine neoplasm is included in the 2019 WHO classification and defined as having more than 30% of both neuroendocrine and non-neuroendocrine tumor components. However, the number of reports on mixed neuroendocrine and non-neuroendocrine tumors is particularly small. Herein, we encountered a rare case of a tiny neuroendocrine carcinoma in a large flat-elevated rectal tumor resulting in rapid multiple liver metastases. This case was referred to our institution for endoscopic submucosal dissection. Histopathological analysis showed that tubular adenocarcinoma and adenoma were the predominant lesions. Moreover, the neuroendocrine carcinoma component was less than 3% of the total tumor, measuring approximately 5 mm. However, the neuroendocrine carcinoma component was found to be the most advanced part of the infiltrate (T1b at least; SM3.8 mm). Repeat computed tomography 1 week after endoscopic submucosal dissection for evaluating intraoperative perforation revealed liver metastasis, and chemotherapy is currently underway.

Transcriptome of sessile serrated adenoma/polyps is associated with MSI-high colorectal cancer and decreased expression of CDX2.

The objective of this study was to elucidate the molecular background of sessile serrated adenoma/polyp (SSA/P) endoscopically resected with comprehensive gene expression analysis. Gene expression profiling was performed for 10 tumor-normal pairs of SSA/P. Cluster analysis, gene set enrichment analysis (GSEA), and consensus molecular subtype (CMS) classification of colorectal cancer (CRC) were applied to our transcriptome analysis. Unsupervised cluster analysis showed that the gene expression profile of SSA/Ps is different from that of adjacent normal epithelial cells, even in the very early stage of tumorigenesis. According to the CMS classification, our microarray data indicated that SSA/Ps were classified as CMS1. GSEA demonstrated a strong association between SSA/P and microsatellite instability-high (MSI-H) CRC (p < 10-5 ). Transcriptome analysis of five MSI-related genes (MSH2, MSH6, MLH1, PMS1, and PMS2) and five CRC-related genes (BRAF, KRAS, APC, TP53, and CDX2) showed that CDX2 expression was most severely decreased in SSA/P. Immunohistochemical staining confirmed that CDX2 protein was reduced compared with the surrounding mucosa. Direct sequencing of the BRAF gene showed that the BRAF V600E mutation was detected in only nine of 36 cases. In a mouse model, BRAF, APC, or CDX2 deficiency indicated that the gene expression pattern with loss of CDX2 is more similar to our SSA/Ps compared with those induced by BRAF or APC mutation. Transcriptome analysis of SSA/Ps showed characteristic gene expression with a strong resemblance to MSI-H CRC. Downregulation of CDX2 expression is an essential molecular mechanism involved in the initial stage of SSA/P tumorigenesis. (UMIN000027365).