Fusobacterium nucleatum promotes M2 polarization of macrophages in the microenvironment of colorectal tumours via a TLR4-dependent mechanism

Fusobacterium nucleatum (Fn) has been shown to promote colorectal cancer (CRC) development by inhibiting host anti-tumour immunity. However, the impact of Fn infection on macrophage polarization and subsequent intestinal tumour formation as well as the underlying molecular pathways has not been investigated. We investigated the impact of Fn infection on macrophage polarization in human CRCs and cultured macrophages as well as the effects on macrophage phenotype and intestinal tumour formation in ApcMin/+ mice. We also examined whether macrophage-polarized activation challenged by Fn infection via a TLR4-dependent mechanism involved the IL-6/STAT3/c-MYC signalling cascade. Our data showed that macrophages are a major tumour-infiltrating immune cell type in human CRCs with Fn infection (P < 0.001). Fn infection increased M2 polarization of macrophages in vitro and in vivo, leading to intestinal tumour growth in ApcMin/+ mice. Moreover, Fn infection induced high expression of TLR4, IL-6, STAT3, p-STAT3, and c-MYC in cultured macrophages challenged with Fn, which was blocked by TAK-242 pre-treatment (P < 0.05). Interestingly, c-MYC protein was mainly co-localized with CD206+ M2 macrophages with Fn infection. In conclusion, we show that Fn infection increased M2 polarization of macrophages in vitro and in vivo. Furthermore, Fn infection enhanced colorectal tumour growth in a TLR4-dependent manner involving activation of the IL-6/p-STAT3/c-MYC signalling pathway. For the first time, our results indicate an immunosuppressive effect of Fn by promoting M2 polarization of macrophages through a TLR4-dependent mechanism, which may serve as a promising target for immunotherapy of Fn-related CRC.

Klotho: a tumor suppressor and modulator of the Wnt/β-catenin pathway in human hepatocellular carcinoma

Klotho, an anti-aging gene, has recently been shown to contribute to human hepatic tumorigenesis. In addition, it is known that Wnt signaling is antagonized by the protein klotho. Because augmented Wnt signaling has an important role in tumorigenesis of human hepatocellular carcinoma (HCC), we studied the relationship of klotho expression and activity to the Wnt pathway in this malignancy. Immunohistochemical analysis performed on tissue arrays revealed that klotho expression levels were significantly lower in HCC than in adjacent noncancerous tissues, while klotho staining was inversely correlated with clinical stage and histologic grade. Patients with klotho-expressing tumors had longer survival periods than did those with klotho-negative tumors. Overexpression of klotho as well as treatment with soluble klotho protein reduced hepatoma cell growth in vitro and in vivo, whereas klotho silencing enhanced cellular proliferation. Moreover, forced expression of klotho inhibited Wnt/β-catenin signaling, as confirmed by reduced expression of β-catenin, inhibition of translocation of β-catenin from the cytoplasm to the nucleus, and reduced expression of c-myc and cyclin D1, two known target genes of the Wnt/β-catenin pathway. In contrast, activation of the Wnt/β-catenin pathway was enhanced when klotho was silenced by inhibitory RNAs. Furthermore, serum levels of soluble klotho in patients with malignant tumors were studied, and results suggested a significant increase in these levels in HCC patients. These data suggest that klotho acts as a tumor suppressor and an inhibitor of the Wnt/β-catenin pathway in HCC, and moreover, that soluble klotho is a potential serum biomarker for HCC.

Fusobacterium nucleatum Potentiates Intestinal Tumorigenesis in Mice via a Toll-Like Receptor 4/p21-Activated Kinase 1 Cascade

BACKGROUND

The underlying pathogenic mechanism of Fusobacterium nucleatum in the carcinogenesis of colorectal cancer has been poorly understood.

METHODS

Using C57BL/6-ApcMin/+ mice, we investigated gut microbial structures with F. nucleatum, antibiotics, and Toll-like receptor 4 (TLR4) antagonist TAK-242 treatment. In addition, we measured intestinal tumor formation and the expression of TLR4, p21-activated kinase 1 (PAK1), phosphorylated-PAK1 (p-PAK1), phosphorylated-β-catenin S675 (p-β-catenin S675), and cyclin D1 in mice with different treatments.

RESULTS

Fusobacterium nucleatum and antibiotics treatment altered gut microbial structures in mice. In addition, F. nucleatum invaded into the intestinal mucosa in large amounts but were less abundant in the feces of F. nucleatum-fed mice. The average number and size of intestinal tumors in F. nucleatum groups was significantly increased compared to control groups in ApcMin/+ mice (P < 0.05). The expression of TLR4, PAK1, p-PAK1, p-β-catenin S675, and cyclin D1 was significantly increased in F. nucleatum groups compared to the control groups (P < 0.05). Moreover, TAK-242 significantly decreased the average number and size of intestinal tumors compared to F. nucleatum groups (P < 0.05). The expression of p-PAK1, p-β-catenin S675, and cyclin D1 was also significantly decreased in the TAK-242-treated group compared to F. nucleatum groups (P < 0.05).

CONCLUSIONS

Fusobacterium nucleatum potentiates intestinal tumorigenesis in ApcMin/+ mice via a TLR4/p-PAK1/p-β-catenin S675 cascade. Fusobacterium nucleatum-induced intestinal tumorigenesis can be inhibited by TAK-242, implicating TLR4 as a potential target for the prevention and therapy of F. nucleatum-related colorectal cancer.

Pre-treatment Eckardt score is a simple factor for predicting one-year peroral endoscopic myotomy failure in patients with achalasia

BACKGROUND

Peroral endoscopic myotomy (POEM) is a novel treatment for achalasia with excellent outcomes. But the predictor for treatment failure is not well defined. This study was aimed to prospectively investigate the factors for predicting failed POEM.

METHODS

From June 2011 to May 2015, a total of 115 achalasia patients treated by POEM were included for the retrospective cohort study from Nanfang Hospital and the First People's Hospital of Yunnan Province. Patients were followed up with Eckardt score, high-resolution manometry and endoscope. POEM failure was defined as primary failure (Eckardt score failed to decrease to 3 or below) and recurrences (decrease of Eckardt score to 3 or below, then rise to more than 3) during one-year follow-up. Univariate and multivariate Cox regression analyses were performed to assess the predictive factor. For the associated factor, receiver operating characteristic curve (ROC) was utilized to determine the cutoff value of the predicting factor.

RESULTS

The failure rate of POEM after 1 year was 7.0% (8/115), including 5 primary failure cases and 3 recurrences. Multivariate analysis showed higher pre-treatment Eckardt score was the single independent factor associated with POEM failure [9.5 (6-12) vs. 7 (2-12), odds ratio (OR) 2.24, 95 confidence interval (95% CI) 1.39-3.93, p = 0.001]. The cutoff value (Eckardt score ≥9) had 87.5 sensitivity (95% CI 47.3-99.7%) and 73.8% specificity (95% CI 64.4-81.9%) for predicting failed POEM.

CONCLUSIONS

Pre-treatment Eckardt score could be a predictive factor for failed POEM. Eckardt score ≥9 was associated with high sensitivity and specificity for predicting POEM failure.

Efficacy of prednisone for prevention of esophageal stricture after endoscopic submucosal dissection for superficial esophageal squamous cell carcinoma

BACKGROUND

Our objective was to investigate the efficacy and safety of oral prednisone for the prevention of esophageal stricture formation after endoscopic submucosal dissection (ESD) in an optimal administration program.

METHODS

Patients who underwent circumferential or semi-circumferential (more than three quarters but not a complete circular) ESD for esophageal squamous cell carcinoma were eligible for this study. Oral prednisolone was administered to the study group at a dose of 30 mg/day on the third day post-ESD, and then tapered gradually (30, 25, 20, 15, 10, and 5 mg for 14 days). Serial esophagoscopy with iodine staining was performed to assess stenosis and tumor recurrence at one, three, six, and 12 months after ESD. Endoscopic balloon dilatation was performed whenever patients experienced persistent dysphagia to solids. Data were statistically analyzed.

RESULTS

Twenty-three patients (15 men, mean age 66.6 years) were enrolled in the study. Post-procedural esophageal stricture was significantly lower in the study group (23.1%) compared to the control (80%) (P < 0.05). A significantly higher number of endoscopic balloon dilatation sessions were performed (P < 0.05) in the control (13.5) than in the study group (0.69). There were no adverse events related to oral prednisolone or the procedure itself and no treatment-related mortality was observed during the 12 month follow-up.

CONCLUSIONS

Our study suggested an optimal administration program of oral prednisone therapy and demonstrated that it is safe and effective for the prevention of esophageal stricture in patients after complete or semi-circular ESD for esophageal squamous cell carcinoma.

Autoinducer-2 of Fusobacterium nucleatum promotes macrophage M1 polarization via TNFSF9/IL-1β signaling

The effect of Fusobacterium nucleatum (F. nucleatum) autoinducer-2 (AI-2) on the polarization of macrophages and the underlying mechanism is not known. We investigated the effect of F. nucleatum AI-2 on the migration and polarization of cultured macrophages. We further screened AI-2-interacting proteins in macrophages using a quantitative proteomics strategy, and evaluated the expression of TNFSF9/TRAF1/p-AKT/IL-1β signaling in cultured macrophages and human colorectal cancer (CRC). The data showed that F. nucleatum AI-2 enhanced the mobility and M1 polarization of macrophages, possibly through TNFSF9/TRAF1/p-AKT/IL-1β signaling. Moreover, TNFSF9 and IL-1β expression was significantly increased in human CRCs when compared to normal colon (P < 0.05), and was associated with AI-2 concentration and increased survival. Together, our data suggested that AI-2 induced macrophage M1 polarization by activating the TNFSF9/IL-1β pathway. Thus, AI-2 may serve as a promising novel target for immunotherapy of gut microbiota-related diseases.

Top-cited articles in digestive system disease from 1950 to 2013

BACKGROUND AND AIM

Examination of top-cited articles is a tool that can help to identify and monitor outstanding scientific researches and landmark papers. We aimed to identify the 100 most cited published papers in peer-reviewed biomedical journals in the field of digestive diseases and to examine their characteristics.

METHODS

The Web of Science (including Science Citation Index) was searched for the most cited papers related to digestive diseases, published from 1955 to the present. The top 100 most cited articles were identified. The number of citations, countries, and institutions of origin, year of publication, study design, topic, and levels of evidence of the articles were noted and analyzed.

RESULTS

The most top-cited articles had a mean of 1375 citations. These articles were published between 1978 and 2009 in 29 high-impact journals, with the New England Journal of Medicine (n = 22) topping the list. Of the 100 articles, 34 were clinical studies, 15 were review articles, and 34 were concerned basic science. These articles came from 18 countries, with the USA contributing most of the top-cited articles (n = 53). Eighty-seven institutions produced these 100 top-cited articles, led by the University of Barcelona (n = 4). Seven persons authored two or more of these top-cited articles. The mostly represented specialty was gastrointestinal oncology (n = 49).

CONCLUSIONS

Our study can give a historical perspective on the scientific progress of digestive diseases, as well as allow for recognition of most important advances in this area and provide useful information to guide future researches.

The 2 years' long-term efficacy and safety of peroral endoscopic myotomy for the treatment of achalasia: a systematic review

AIM

In this retrospective review, we aimed to investigate the long-term efficacy and safety of POEM with follow-up period over 2 years.

MATERIALS AND METHODS

A systematic review related to POEM for achalasia was conducted. A literature search was performed in Pubmed, Medline, Ovid, Cochrane and EBSCO databases on November 2017. The following postoperative outcomes were extracted: Eckardt score, lower esophageal sphincter pressure, complications and clinical success.

RESULTS

The total number of patients was 373. The mean operative time was 66.7 min and the overall rate of complications was 21.2%. The mean follow-up period was 30.0 months. The overall clinical success rate was 92.9% and the rate of gastroesophageal reflux disease was 10.2%. Rate of mortality after POEM was 0.

CONCLUSIONS

Our study demonstrated that POEM is effective and safe for treating achalasia during the long-term followed up over 2 years.

Training in early gastric cancer diagnosis improves the detection rate of early gastric cancer: an observational study in China

Few studies have analyzed the training of endoscopists in the diagnosis of early gastric cancer (EGC). This study assessed whether specific training of endoscopists improves the detection rate of EGC. The rates of detection of EGC by endoscopists at the Digestive Endoscopy Center of the Affiliated Nanfang Hospital of China Southern Medical University between January 2013 and May 2014 were retrospectively analyzed. Because some endoscopists received training in the diagnosis of EGC, beginning in September 2013, the study was divided into 3 time periods: January to September 2013 (period 1), September 2013 to January 2014 (period 2), and January to May 2014 (period 3). The rates of EGC detection during these 3 periods were analyzed. From January 2013 to May 2014, a total of 25,314 gastroscopy examinations were performed at our center, with 48 of these examinations (0.2%) detecting EGCs, accounting for 12.1% (48/396) of the total number of gastric cancers detected. The EGC detection rates by trained endoscopists during periods 1, 2, and 3 were 0.3%, 0.6%, and 1.5%, respectively, accounting for 22.0%, 39.0%, and 60.0%, respectively, of the gastric cancers detected during these time periods. In comparison, the EGC detection rates by untrained endoscopists during periods 1, 2, and 3 were 0.05%, 0.08%, and 0.10%, respectively, accounting for 3.1%, 6.0%, and 5.7%, respectively, of the gastric cancers detected during these times. After training, the detection rate by some trained endoscopists markedly increased from 0.2% during period 1 to 2.3% during period 3. Further, the use of magnifying endoscopy with narrow-band imaging (M-NBI) (odds ratio = 3.1, 95% confidence interval 2.4-4.1, P < 0.001) contributed to the diagnosis of EGC. In conclusion, specific training could improve the endoscopic detection rate of EGC. M-NBI contributed to the diagnosis of EGC.

Efficacy and safety of submucosal tunneling endoscopic resection for upper gastrointestinal submucosal tumors with more than 1-year' follow-up: a systematic review and meta-analysis

Objectives: Submucosal tunneling endoscopic resection (STER) is a novel therapeutic approach for upper gastrointestinal submucosal tumors (SMTs) especially for tumors originating from the muscularis propria layer. Presently, several studies have reported the efficacy and safety of STER for SMTs. Therefore, we conducted this study to review the clinical outcomes of STER with more than 1-year' follow-up duration. Materials and methods: Medline, Embase and Cochrane databases were searched on November 2018 to identify studies reporting STER for SMTs. Weighted pooled rates were calculated for en bloc resection, complete resection and adverse event (AE). Risk ratios (RR) were calculated and pooled to compare STER with thoracoscopic enucleation (TE). Results: A total of 701 patients with 728 lesions from 12 original studies were review. Pooled WPR for en bloc resection of STER was 86.3% (95% CI: 74.5-93.1%), (I2=82.5). Pooled WPR for complete resection of STER was 97.7% (95% CI: 92.8-99.3%), (I2=77.6). WPR for AE was 18.3% (95% CI: 9.7-31.6%), (I2=90.6%). Two studies with 292 patients compared the performance of STER with TE. Pooled RR for en bloc resection was 1.02 (95% CI: 0.95-1.09). Pooled RR for complete resection was 1.0 (95% CI: 0.98-1.03). Pooled RR for AE was 0.82 (95% CI: 0.33-2.05). Conclusions: Our study showed that STER has relatively long-term efficacy for treating upper gastrointestinal SMTs, and the incidence of AE was not low for STER, but all of them can be managed conservatively.

Comparison of conventional versus Hybrid knife peroral endoscopic myotomy methods for esophageal achalasia: a case-control study

OBJECTIVE

Peroral endoscopic myotomy (POEM) has been developed to treat achalasia as a novel less invasive modality. We aimed to compare the efficacy and safety of conventional knife versus Hybrid knife (HK) during POEM procedure.

MATERIALS AND METHODS

Between June 2012 and July 2014, 31 patients underwent POEM using HK in our department (HK group), and 36 patients underwent POEM using conventional method (injection needle and triangular tip [TT] knife, TT group). Procedure-related parameters, symptom relief, adverse events were compared between two groups.

RESULTS

There were no significant differences in the age, sex and other baseline characteristics between the two groups. The mean procedural time was significantly shorter in HK group than TT group (53.0 ± 17.2 vs. 67.6 ± 28.4 min, p = 0.015). The mean frequency of devices exchange was 4.7 ± 1.7 in HK group and 10.9 ± 1.8 in TT group (p = 0.000). No serious adverse events occurred postoperatively in both groups. At one-year follow-up, a total of 94% treatment success was achieved in all patients (93.5% in HK group and 94.4% in TT group, p = 0.877).

CONCLUSION

HK in POEM can shorten the procedural time, and achieve similar treatment success compared to conventional TT knife.

Peroral endoscopic shorter versus longer myotomy for the treatment of achalasia: a comparative retrospective study

INTRODUCTION

Peroral esophageal myotomy (POEM) is a novel endoscopic treatment for achalasia. It has gained popularity worldwide among surgeons and endoscopists, but no studies have compared peroral endoscopic short with long myotomy for achalasia. We aimed to compare the clinical efficacy and safety between peroral endoscopic shorter and longer myotomy.

METHODS

The retrospective study enrolled 129 achalasia patients who underwent POEM from July 2011 to September 2017. Based on the myotomy length (ML), patients were divided into shorter myotomy (SM) group (ML ≤ 7 cm, n = 36) and longer myotomy (LM) group (ML > 7 cm, n = 74). Procedure-related parameters, symptom scores, adverse events and manometric data were compared between two groups.

RESULTS

The mean ML was 6.0 ± 0.6 cm in SM group, and 11.5 ± 3.1 cm in LM group (p < 0.001). The mean operation time was significantly less in SM group than LM group (46.6 ± 18.5 min vs 62.1 ± 25.2 min, p = 0.001). During a mean follow-up period of 28.7 months, treatment success (Eckardt score ≤ 3) was achieved in 94.4% (34/36) of patients in SM group and 91.9% (68/74) in LM group (p = 0.926). There was no statistical difference in the incidence of intraoperative complications (8.4% vs 8.2%, p = 0.823) and reflux rate (8.3% vs. 14.9%, p = 0.510) between two groups.

CONCLUSIONS

Peroral endoscopic shorter myotomy is comparable with longer myotomy for treating achalasia with regard to clinical efficacy and has the advantage of shorter procedure time.

The safety and efficacy of endoscopic ultrasound-guided ablation therapy for solid pancreatic tumors: a systematic review

BACKGROUND AND AIMS

Recently, endoscopic ultrasound (EUS)-guided ablation therapy, as a minimally invasive technique, has shown its potential to substitute surgery in treating solid pancreatic tumors, such as small potential malignant pancreatic tumors, small insulinomas and locally advanced pancreatic ductal adenocarcinoma (LAPDAC). Therefore, we conducted this systematic review to assess the safety and efficacy of EUS-guided ablation therapy for solid pancreatic tumors.

METHODS

We conducted a comprehensive search of PubMed, Embase, Cochrane library and Web of Science databases from inception to February 2020. The endpoints were clinical success and complications rates. The pooled event rate was calculated using Comprehensive Meta Analysis software.

RESULTS

Fourteen studies with a total of 158 patients were included in our final analysis. The major types of solid pancreatic tumors were nonfunction pancreatic neuroendocrine tumors (n = 78, 49.4%), LAPDAC (n = 48, 30.4%) and insulinomas (n = 26, 16.5%). Overall, the pooled clinical success rate was 85.9% (95% confidence interval (CI): 75.4-92.4%, I 2 = 25.18%), pooled complications rate was 29.1% (95% CI: 18.6-42.3%, I 2 = 50.40%). Subgroup analysis was performed based on ablation methods, which showed clinical success rate for radiofrequency ablation (RFA) was 83.5% (95% CI: 67.9-92.4%), and 87.9% (95% CI: 66.2-96.4%) for ethanol ablation (EA). In terms of complications rate, it was 32.2% (95% CI: 19.4-48.4%) for RFA, and 21.2% (95% CI: 6.8-49.9%) for EA.

CONCLUSIONS

EUS-guided ablation therapy is a promising alternative treatment for solid pancreatic tumors, especially for p-NETs and insulinomas < 2 cm, with rarely severe complications. Further prospective studies with long-term follow-up are warranted in future.

Clinical outcomes of endoscopic ultrasound-guided gastroenterostomy for gastric outlet obstruction: a systematic review and meta-analysis

BACKGROUND AND AIMS

EUS-guided gastroenterostomy (EUS-GE) has been used for gastric outlet obstruction (GOO) with promising clinical outcomes. Therefore, we aimed to determine the clinical outcomes of EUS-GE for GOO.

MATERIAL AND METHODS

We used the keyword 'EUS-guided gastroenterostomy' to search in Pubmed, Web of science, Cochrane databases. Clinical outcomes of EUS-GE were evaluated in terms of technical success, clinical success and complications.

RESULTS

Ten studies reported 297 patients managed with EUS-GE. Weighted pooled rates (WPR) for technical success, clinical success and complications of EUS-GE were 91% (95%CI 87%-94%), 88% (95%CI 83%-91%) and 6.8% (95%CI 4.1%-11.0%). The most common complications were abdominal pain, 6.7% (95%CI 2.5%-16.5%) and bleeding, 4.8% (95%CI 1.5%-13.9%). Two studies compared EUS-GE with surgical gastrojejunostomy (SGJ). Pooled risk ratio (RR) for technical success, clinical success and complications were 0.87 (0.78, 0.97), I2 = 0%; 0.92 (0.82, 1.04), I2 = 0%; 0.28 (0.11, 0.68), I2 = 0%. Three studies compared benign GOO with malignant GOO. RR for technical success and clinical success were 1.05 (0.82, 1.34), I2 = 0%; 0.98 (0.72, 1.33), I2 = 0%.

CONCLUSIONS

Although EUS-GE and SGJ had similar clinical success rates, EUS-GE had a lower complication rate. EUS-GE is a safe, effective, and minimally invasive choice for patients with GOO.

Expression of klotho and β-catenin in esophageal squamous cell carcinoma, and their clinicopathological and prognostic significance

Esophageal carcinoma is one of the most common types of cancers in the world; the molecular mechanism underlying its tumorigenesis is still not well understood. This study was aimed at investigating the expression of klotho and β-catenin in patients with esophageal squamous cell carcinoma (ESCC) and analyzing their association with clinicopathological variables and their effects on prognosis. The expression patterns of klotho and β-catenin were determined by tissue microarray and immunohistochemical technique in ESCC and normal tissues, and their correlations with clinicopathological characteristics were investigated using univariate and multivariate analysis. The serum klotho levels in 40 ESCC patients and controls were measured by sandwich enzyme-linked immunosorbent assay system (ELISA). The expression level of klotho was significantly lower in ESCC than in the adjacent noncancerous tissues (30 vs. 50%, P < 0.000), and the protein level was negative correlated with clinical staging, histological grade, lymph node metastasis, and invasion depth (P < 0.05). Whereas, the expression of β-catenin was much higher in ESCC than their corresponding normal mucosa tissues (78.3 vs. 11.5%, P < 0.000), and the level of protein correlated only with histological grade and invasion depth (P < 0.05). Correlation analysis showed the expression level of klotho inversely correlated with that of β-catenin (r = -0.214, P < 0.01). Patients with klotho-positive tumors had longer survival than those with klotho-negative tumors (P < 0.01). Cox proportional hazards model analysis demonstrated that positive expression of klotho was an important factor indicating good prognosis (hazard ratio, 0.371; 95% confidence interval, 0.201-0.685; P < 0.01). ELISA showed that the level of serum klotho was markedly higher (461.50 ± 43.30 pg/mL) than control group (239.37 ± 20.65 pg/mL) (P < 0.001). Receiver operating characteristic analysis gave a cut-off value of 327.031 of serum klotho with a sensitivity of 81.3% and specificity of 81.2% (P < 0.000). Our present study demonstrated for the first time that klotho might be a novel biomarker candidate for predicting progression and prognosis in patients with ESCC.

Clinical outcomes of endoscopic resection for the treatment of gastric gastrointestinal stromal tumors originating from the muscularis propria: a 7-year experience from a large tertiary center in China

BACKGROUND AND AIMS

Few studies have evaluated the value of endoscopic resection (ER) for the treatment of gastric gastrointestinal (GI) stromal tumors (GISTs) originating from the muscularis propria (MP) in a large population, and no studies have evaluated risk factors for piecemeal resection. This study aimed to evaluate the efficacy and safety of ER for gastric GISTs in a real-world setting and to explore factors associated with piecemeal resection.

METHODS

From January 2013 to December 2019, 185 patients with gastric GISTs originating from the MP were assessed. Clinicopathological and endoscopic data were collected and analyzed. Baseline characteristics of the en bloc resection and piecemeal resection groups were compared to evaluate predictive factors for piecemeal resection.

RESULTS

There were 71 males and 114 females with a mean age of 57.0 ± 9.7 years. The mean size of GISTs was 15 mm (range 4-65 mm). A total of 123 were very low risk, 52 were low risk, and ten were moderate risk. In this study, 103 GISTs were treated with endoscopic submucosal excavation (ESE), 68 GISTs were treated with endoscopic full-thickness resection (EFR), and 14 GISTs were treated with submucosal tunneling ER (STER). Either en bloc resection or complete resection was achieved in 160 (86.5%) patients. No recurrence was noted during follow-up. Only five patients experienced minor complications, with a complication rate of 2.7%. Multivariate analysis demonstrated that size (odds ratio [OR] 1.060, 95% confidence interval [CI] 1.004-1.118; P = 0.035) and shape (OR 5.434, 95% CI 1.638-18.027; P = 0.006) were independent predictors of piecemeal resection.

CONCLUSION

ER was effective and safe for the treatment of gastric GISTs originating from the MP. Piecemeal resection did not seem to affect the efficacy of ER, and no recurrence was noted during follow-up. Large size and irregular shape are risk factors related to piecemeal resection of ER.

Single-operator peroral cholangioscope in treating difficult biliary stones: A systematic review and meta-analysis

BACKGROUND AND AIM

Current evidence supporting the utility of single-operator peroral cholangioscope (SOPOC) in the management of difficult bile duct stones is limited. We conducted the present systematic review and meta-analysis to evaluate the efficacy and safety of SOPOC in treating difficult bile duct stones.

METHODS

We searched studies up to April 2018, using MEDLINE, EMBASE, the Cochrane Library, and Google Scholar. Quality assessment of the studies was completed with the Newcastle-Ottawa Scale. Main outcomes were complete stone clearance rate, single-session stone clearance rate, number of endoscopic sessions needed for stone clearance, and adverse events. We calculated the pooled estimates with random-effects models. Potential publication bias was assessed.

RESULTS

Twenty-four studies involving 2786 patients met the inclusion criteria. Pooled proportion of patients with complete stone clearance was 94.3% (95% confidence interval [95% CI]: 90.2-97.5%). Single-session stone clearance was achieved in 71.1% (95% CI: 62.1-79.5%) of the pooled patients. Pooled number of sessions needed for stone clearance was 1.26 (95% CI: 1.17-1.34%). Pooled adverse event rate was 6.1% (95% CI: 3.8-8.7%). Potential publication bias was detected but had no significant influence on the results.

CONCLUSIONS

Single-operator peroral cholangioscope is an effective and safe treatment for difficult bile duct stones when conventional methods have failed. More randomized controlled trials are warranted to confirm the results.

Peroral endoscopic myotomy is safe and effective in achalasia patients aged older than 60 years compared with younger patients

AIM

Peroral endoscopic myotomy (POEM) has been proven to be effective for treating achalasia, but there are limited data on POEM in elderly patients. We therefore aimed to assess the role of POEM for achalasia in patients aged ≥60 years.

METHODS

All consecutive patients that underwent POEM between December 2011 and November 2015 at a single center were retrospectively reviewed. Patients aged ≥60 years were assigned to group A, whereas patients aged <60 years were assigned to group B. Demographic data, clinical data and treatment outcomes were compared between the two groups.

RESULTS

During the study period, 113 patients (18 in group A, and 95 in group B) were enrolled. The mean age of patients in group A was 63 ± 3.9 years (range 60-74 years; 55.6% women), and that for patients in group B was 37.7 ± 11.6 years (range 18-59 years; 42.2% women). The procedural time in group A was similar to group B (66.3 ± 33.3 vs 59.8 ± 24.2 min, P = 0.332). There were also no significant differences in the incidence of intraoperative complications (P = 1.000) and gastroesophageal reflux rate (P = 0.906) between the two groups. During the mean follow-up period of 25.2 months, treatment success (Eckardt score ≤3) was achieved in 92.9% of patients in group A, and 89.9% in group B (P = 1.000).

CONCLUSIONS

As well as in younger patients, POEM can be safely carried out in elderly patients, providing significant symptom relief. POEM might be recommended as the first therapeutic approach to elderly achalasia patients. Geriatr Gerontol Int 2017; 17: 2407-2413.

Usefulness of peroral endoscopic myotomy for treating achalasia in children: experience from a single center

INTRODUCTION

Achalasia is a rare esophageal motility disorder in the pediatric population. Peroral endoscopic myotomy (POEM) has been demonstrated to be effective and safe for the treatment of achalasia as a novel endoscopic technique, but data involving its utility in pediatric patients are limited. We aimed to assess the safety and efficacy of POEM for pediatric patients with achalasia.

MATERIALS AND METHODS

Between July 2012 and August 2014, five consecutive pediatric patients (2 female and 3 male, with a median age of 15 years) with achalasia underwent POEM in our center. Diagnosis was based on symptoms, manometry, radiology and endoscopy. Preoperative and postoperative symptoms scores, and manometry outcomes were recorded and analyzed.

RESULTS

Procedure was performed successfully in all patients, and the median time required for the procedure was 50 min (range 40-90 min). There were no mortalities and no serious intraoperative and postoperative complications. The median length of myotomy was 8 cm (range 6-11 cm). During a median follow-up period of 18 months, treatment success (Eckardt score ≤3) was achieved in all patients. There was a significant improvement of symptoms relief, dysphagia score and lower esophageal sphincter pressure decrease after POEM. No patient developed gastroesophageal reflux disease.

CONCLUSION

Our study suggests that POEM is a safe and effective technique for treating pediatric achalasia. Further studies with long-term follow-up in large-volume pediatric patients are warranted to clearly define the durability of the procedure.

Silver-nanoparticle-coated biliary stent inhibits bacterial adhesion in bacterial cholangitis in swine

BACKGROUND

One of the major limitations of biliary stents is the stent occlusion, which is closely related to the over-growth of bacteria. This study aimed to evaluate the feasibility of a novel silver-nanoparticle-coated polyurethane (Ag/PU) stent in bacterial cholangitis model in swine.

METHODS

Ag/PU was designed by coating silver nanoparticles on polyurethane (PU) stent. Twenty-four healthy pigs with bacterial cholangitis using Ag/PU and PU stents were randomly divided into an Ag/PU stent group (n=12) and a PU stent group (n=12), respectively. The stents were inserted by standard endoscopic retrograde cholangiopancreatography. Laboratory assay was performed for white blood cell (WBC) count, alanine aminotransferase (ALT), interleukin-1beta (IL-1beta), tumor necrosis factor-alpha (TNF-alpha) at baseline time, 8 hours, 1, 2, 3, and 7 days after stent placements. The segment of bile duct containing the stent was examined histologically ex vivo. Implanted biliary stents were examined by a scan electron microscope. The amount of silver release was also measured in vitro.

RESULTS

The number of inflammatory cells and level of ALT, IL-1beta and TNF-alpha were significantly lower in the Ag/PU stent group than in the PU stent group. Hyperplasia of the mucosa was more severe in the PU stent group than in the Ag/PU stent group. In contrast to the biofilm of bacteria on the PU stent, fewer bacteria adhered to the Ag/PU stent.

CONCLUSIONS

PU biliary stents modified with silver nanoparticles are able to alleviate the inflammation of pigs with bacterial cholangitis. Silver-nanoparticle-coated stents are resistant to bacterial adhesion.

Endoscopic Submucosal Tunnel Dissection for Upper Gastrointestinal Submucosal Tumors Originating from the Muscularis Propria Layer: A Single-Center Study

BACKGROUND/AIMS

In recent years, endoscopic submucosal tunnel dissection (ESTD) has gained popularity worldwide. The aim of this study was to evaluate the safety and efficacy of ESTD in treating upper gastrointestinal submucosal tumors (SMTs) in a large-volume endoscopic center.

METHODS

Patients with SMTs were enrolled in this study between January 2012 and January 2015. Demographic data, clinical data, and treatment outcome were collected and analyzed.

RESULTS

Seventy SMTs originating from the muscularis propria (MP) layer were identified in 69 patients. All patients successfully underwent the ESTD procedure. The mean procedure time was 49.0±29.5 minutes, and the mean tumor size was 18.7±7.2 mm. Among all lesions, the majority (70.0%) were located in the esophagus, 12.9% in the cardia, and 17.1% in the stomach. Complete resection was achieved in 67 lesions (95.7%). Perforation occurred in three patients (4.3%), who were treated by endoclips. Pneumothorax occurred in two patients (2.9%) and was successfully managed by thoracic drainage. During a median follow-up of 18.1 months, patients were free of local recurrence or distant metastasis.

CONCLUSIONS

Our results demonstrated the feasibility and safety of ESTD in treating upper gastrointestinal SMTs originating from the MP layer. Large-scale comparative studies with other treatment methods should be conducted in the future.

Bibliometric Analysis of 100 Top-Cited Articles in Gastric Disease

OBJECTIVES

The bibliometric analysis uses the citation count of an article to measure its impact in the scientific community, yet there is still no comprehensive summary of gastric disease researches via bibliometric analysis. We aimed to evaluate the situations and trends of the most cited articles in gastric disease via bibliometric analysis and to provide physicians a practical guide in assessing the most influential articles written on this subject.

METHODS

The 100 top-cited articles in gastric disease were compiled using Web of Science. The articles selected were evaluated for their number of citations, year of publication, country of origin, type of study, and others.

RESULTS

The database had 484,281 articles published between 1965 and 2019. The most cited article received 4,017 citations and the least received 604, with a mean of 1,149 citations. We classified the articles into seven categories: gastric cancer (n = 53), Helicobacter pylori (n = 17), ulcer (n = 7), gastrointestinal stromal tumors (n = 6), gastritis (n = 5), gastric bypass surgery (n = 2), and others (n = 10). Altogether, 69 of the articles were from the USA (n = 41), the UK (n = 17), and Japan (n = 11). Among all the institutions, Royal Perth Hospital led the list with 5 articles. One-quarter of authors owned three or more of these top-cited articles. The 100 papers were published in 33 journals, and most of them were clinical researches (n = 47).

CONCLUSIONS

Our study provides a historical perspective for the scientific progress of gastric disease, and the articles of significant findings that contributed great impact on the prevention and treatment of gastric disease had been identified.

Mid-Term and Long-Term Outcomes of Peroral Endoscopic Myotomy for the Treatment of Achalasia: A Systematic Review and Meta-Analysis

BACKGROUND AND AIMS

Peroral endoscopic myotomy (POEM) achieves a satisfactory short-term clinical response in patients with achalasia. However, data on mid- and long-term clinical outcomes are limited. We aimed to assess the mid- and long-term efficacy and safety of POEM in achalasia patients.

METHODS

Using the pre-designed search strategy, we identified relevant studies that evaluated the efficacy and safety of POEM with a minimum of 2-year follow-up in the Embase, Cochrane, and PubMed databases from inception to January 2021. Primary outcome was pooled mid- and long-term clinical success rate based on the Eckardt score. Secondary outcome was pooled long-term reflux-related adverse events.

RESULTS

A total of 21 studies involving 2,698 patients were included. Overall, the pooled clinical success rates with 2-, 3-, 4-, and 5-year follow-ups were 91.3% (95% confidence interval [CI] 88.4-93.6%), 90.4% (95% CI 88.1-92.2%), 89.8% (95% CI 83.6-93.9%), and 82.2% (95% CI 76.6-86.7%), respectively. Besides, the pooled long-term clinical success rates for type I, II, and III achalasia were 86.1% (95% CI 80.9-90.1%; I2 = 0%), 87.9% (95% CI 84.2-90.8%; I2 = 48.354%), and 83.9% (95% CI 72.5-91.2%; I2 = 0%), respectively. Moreover, the pooled incidence of symptomatic reflux and reflux esophagitis was 23.9% (95% CI 18.7-29.9%) and 16.7% (95% CI 11.9-23.1%), respectively.

CONCLUSIONS

POEM is associated with a long-term clinical success of 82.2% after 5 years of follow-up. Randomized control trials comparing POEM with laparoscopic Heller myotomy or pneumatic dilation with longer follow-up periods are needed to further demonstrate the long-term safety and efficacy of POEM.

Clinical outcomes of over-the-scope-clip system for the treatment of acute upper non-variceal gastrointestinal bleeding: a systematic review and meta-analysis

BACKGROUND

Conventional endoscopic treatments can't control bleeding in as many as 20% of patients with non-variceal gastrointestinal (GI) bleeding. Recent studies have shown that over-the-scope-clip (OTSC) system allowed for effective hemostasis for refractory GI bleeding lesions. So we aimed to conduct a systematic review to evaluate the effectiveness and safety of the OTSC system for management of acute non-variceal upper GI bleeding.

METHOD

A comprehensive literature search was conducted on PubMed, EMBASE, and Cochrane Library covering the period from January 2007 to May 2019. The literature was selected independently by two reviewers according to the inclusion and exclusion criteria. The statistical analysis was carried out using Comprehensive Meta-Analysis software version 3.0.

RESULTS

A total of 16 studies including 769 patients with 778 GI bleeding lesions were identified. Pooled technical success was achieved in 761 lesions [95.7%; 95% confidence interval (CI), 93.5-97.2%], and the pooled clinical success was achieved in 666 lesions (84.2, 95% CI, 77.4-89.2%). The incidence of re-bleeding was reported in 81 patients and the post-procedure mortality was 10.9% (n = 84). Only 2 (0.3%) patients occurred complications after OTSC system procedure.

CONCLUSIONS

Our study demonstrated that the OTSC system was a technically feasible modality and highly efficacious in achieving hemostasis in acute non-variceal upper gastrointestinal bleeding.

Factors predicting the technical difficulty of peroral endoscopic myotomy for achalasia

BACKGROUND

Peroral endoscopic myotomy (POEM) has been described as a novel treatment for esophageal achalasia. Owing to its technical difficulty, POEM is not widely performed. This study was aimed to prospectively assess the factor predicting technical difficulty of POEM in a single center with large volume cases.

METHODS

A total of 105 cases of achalasia treated by POEM from April 2011 to September 2014 were analyzed. Difficult cases of POEM were defined as procedure time ≥90 min and occurrence of adverse events, including mucosal perforation, pneumothorax, and major bleeding. Univariate and multivariate logistic regression analyses were performed to assess the predictive factors of difficult POEM.

RESULTS

POEM was successfully completed in all the patients, and no one was converted to laparoscopy. The number of cases with procedure time ≥90 min was 17. Mucosal perforations occurred in six (5.7 %) patients during submucosal tunnel creation, major bleeding occurred in seven (6.7 %) patients, and pneumothorax occurred in six (5.7 %) patients immediately after procedure. All the complications were managed conservatively. No other intraoperative and immediate postoperative complications, including infections and pneumoperitoneum, occurred. Multivariate analysis showed that early period (odds ratio [OR] 4.173, 95 % confidence interval [95 % CI] 1.36-6.829, P = 0.023) and triangular tip knife ([OR] 6.712, [95 % CI] 1.479-30.460, P = 0.014) were independent factors associated with technical difficulty regarding longer procedure time (procedure time ≥90 min).

CONCLUSION

POEM is safe for the treatment of esophageal achalasia. Triangular tip knife and early period were independent risk factors for longer procedural time.