Technical Variations and Considerations around OAGB in IFSO-APC and IFSO-MENAC Chapters, an Expert Survey

OBJECTIVE

This study aimed to evaluate the technical variations of one-anastomosis gastric bypass (OAGB) among IFSO-APC and MENAC experts.

BACKGROUND

The multitude of technical variations and patient selection challenges among metabolic and bariatric surgeons worldwide necessitates a heightened awareness of these issues. Understanding different perspectives and viewpoints can empower surgeons performing OAGB to adapt their techniques, leading to improved outcomes and reduced complications.

METHODS

The scientific team of IFSO-APC, consisting of skilled bariatric and metabolic surgeons specializing in OAGB, conducted a confidential online survey. The survey aimed to assess technical variations and considerations related to OAGB within the IFSO-APC and IFSO-MENAC chapters. A total of 85 OAGB experts participated in the survey, providing their responses through a 35-question online format. The survey took place from January 1, 2024, to February 15, 2024.

RESULTS

Most experts do not perform OAGB for children and adolescents younger than 18 years. Most experts create the gastric pouch over a 36-40-F bougie and prefer to create a gastrojejunostomy, at the posterior wall of the gastric pouch. An anti-reflux suture during OAGB is performed in all patients by 51.8% of experts. Most experts set a common limb length of > 4 m in revisional and conversional OAGBs to prevent nutritional complications.

CONCLUSION

The ongoing debate among metabolic and bariatric surgeons regarding the technical variations and patient selection in OAGB remains a significant point of discussion. This survey demonstrated the variations in technical aspects and patient selection for OAGB among MBS surgeons in the IFSO-APC and IFSO-MENAC chapters. Standardizing the OAGB technique is crucial to ensure optimal safety and efficacy in this procedure.

A 10-year experience with anastomotic leaks in upper gastrointestinal surgery-Retrospective cohort study

BACKGROUND

Anastomotic leak (AL) in upper gastrointestinal (UGI) surgery continues to be a diagnostic challenge. We seek to identify clinical parameters that predict AL and examine the effectiveness of investigations in evaluating AL following UGI surgeries.

METHODS

592 patients underwent UGI surgeries with an anastomosis between January 2011 and January 2021. Data on patient characteristics, surgery, postoperative investigations and outcomes were prospectively collected and analysed.

RESULTS

The overall occurrence of AL was 6.4 %. Tachycardia >120 BPM (OR 6.959, 95 % CI 1.856-26.100, p = 0.004) and leukocyte count >19 × 109/L (OR 3.327, 95 % CI 1.009-10.967, p = 0.048) were independent predictors of AL. On multivariate analysis, patients whose anastomosis was deemed high risk and had pre-emptive investigation done postoperatively to exclude a leak were less likely to require intervention and were more likely to be managed conservatively (66.7 % vs 14.3 %, p = 0.025). Methylene blue test, oral contrast study and Computed Tomography scan with intravenous and oral contrast had 50.0 %, 20.0 % and 9.1 % false negative results, while esophagogastroduodenoscopy had none. There was no misdiagnosed AL when more than 1 investigation (n = 15, 39.5 %) were performed.

CONCLUSION

Our study demonstrates that the presence of a triad including desaturation, tachycardia and leucocytosis predicts for AL following UGI surgery and for confirmation of a leak, evaluation with 2 or more investigation is needed. A practice of evaluating high risk anastomosis prior to commencement of feeding decreased the need for surgical intervention and improves success of conservative treatment.

A systematic review and meta-analysis of mediastinoscopy-assisted transhiatal esophagectomy (MATHE)

BACKGROUND

Transhiatal esophagectomy (THE) avoids thoracotomy but sacrifices mediastinal lymphadenectomy. Mediastinoscopy-assisted transhiatal esophagectomy (MATHE) allows for visualisation and en-bloc dissection of mediastinal lymph nodes while retaining the benefits of THE. However, given its novel inception, there is a paucity of literature. This study aimed to conduct the first meta-analysis to explore the efficacy of MATHE and clarify its role in the future of esophagectomy.

METHODS

Four databases (PubMed, EMBASE, Scopus, and Cochrane Library) were searched from inception to May 1, 2023. Studies were included if they reported outcomes for patients with esophageal cancer who underwent MATHE. Meta-analyses of proportions and pooled means were performed for the outcomes of intraoperative blood loss, lymph node (LN) harvest, mean hospital length of stay (LOS), mean operative time, R0 resection, conversion rates, 30-day mortality rate, 5-year OS, and surgical complications (anastomotic leak, cardiovascular [CVS] and pulmonary complications, chyle leak and recurrent laryngeal nerve palsy [RLN]). Sensitivity analyses were performed for outcomes with substantial statistical heterogeneity.

RESULTS

The search yielded 223 articles; 28 studies and 1128 patients were included in our analysis. Meta-analyses of proportions yielded proportion rates: 30-day mortality (0 %, 95 %CI 0-0), 5-year OS (60.5 %, 95 %CI 47.6-72.7), R0 resection (100 %, 95 %CI 99.3-100), conversion rate (0.1 %, 95 %CI 0-1.2). Among surgical complications, RLN palsy (14.6 %, 95 %CI 9.5-20.4) were most observed, followed by pulmonary complications (11.3 %, 95 %CI 7-16.2), anastomotic leak (9.7 %, 95 %CI 6.8-12.8), CVS complications (2.3 %, 95 %CI 0.9-4.1) and chyle leak (0.02 %, 95 %CI 0-0.8). Meta-analysis of pooled means yielded means: LN harvest (18.6, 95 %CI 14.3-22.9), intraoperative blood loss (247.1 ml, 95 %CI 173.6-320.6), hospital LOS (18.1 days, 95 %CI 14.4-21.8), and operative time (301.5 min, 95 %CI 238.4-364.6). There was moderate-to-high statistical heterogeneity. Findings were robust to sensitivity analyses.

CONCLUSION

MATHE is associated with encouraging post-operative mortality and complication rates, while allowing for radical mediastinal lymphadenectomy with reasonable lymph node harvest.

Current recommendations for procedure selection in class I and II obesity developed by an expert modified Delphi consensus

Metabolic and bariatric surgery (MBS) is widely considered the most effective option for treating obesity, a chronic, relapsing, and progressive disease. Recently, the American Society of Metabolic and Bariatric Surgery (ASMBS) and the International Federation for the Surgery of Obesity and Metabolic Disorders (IFSO) issued new guidelines on the indications for MBS, which have superseded the previous 1991 National Institutes of Health guidelines. The aim of this study is to establish the first set of consensus guidelines for selecting procedures in Class I and II obesity, using an Expert Modified Delphi Method. In this study, 78 experienced bariatric surgeons from 32 countries participated in a two-round Modified Delphi consensus voting process. The threshold for consensus was set at an agreement or disagreement of ≥ 70.0% among the experts. The experts reached a consensus on 54 statements. The committee of experts reached a consensus that MBS is a cost-effective treatment option for Class II obesity and for patients with Class I obesity who have not achieved significant weight loss through non-surgical methods. MBS was also considered suitable for patients with Type 2 diabetes mellitus (T2DM) and a body mass index (BMI) of 30 kg/m2 or higher. The committee identified intra-gastric balloon (IGB) as a treatment option for patients with class I obesity and endoscopic sleeve gastroplasty (ESG) as an option for patients with class I and II obesity, as well as for patients with T2DM and a BMI of ≥ 30 kg/m2. Sleeve gastrectomy (1) and Roux-en-Y gastric bypass (RYGB) were also recognized as viable treatment options for these patient groups. The committee also agreed that one anastomosis gastric bypass (OAGB) is a suitable option for patients with Class II obesity and T2DM, regardless of the presence or severity of obesity-related medical problems. The recommendations for selecting procedures in Class I and II obesity, developed through an Expert Modified Delphi Consensus, suggest that the use of standard primary bariatric endoscopic (IGB, ESG) and surgical procedures (SG, RYGB, OAGB) are acceptable in these patient groups, as consensus was reached regarding these procedures. However, randomized controlled trials are still needed in Class I and II Obesity to identify the best treatment approach for these patients in the future.

Public acceptance of using artificial intelligence-assisted weight management apps in high-income southeast Asian adults with overweight and obesity: a cross-sectional study

Introduction

With in increase in interest to incorporate artificial intelligence (AI) into weight management programs, we aimed to examine user perceptions of AI-based mobile apps for weight management in adults with overweight and obesity.

Methods

280 participants were recruited between May and November 2022. Participants completed a questionnaire on sociodemographic profiles, Unified Theory of Acceptance and Use of Technology 2 (UTAUT2), and Self-Regulation of Eating Behavior Questionnaire. Structural equation modeling was performed using R. Model fit was tested using maximum-likelihood generalized unweighted least squares. Associations between influencing factors were analyzed using correlation and linear regression.

Results

271 participant responses were analyzed, representing participants with a mean age of 31.56 ± 10.75 years, median (interquartile range) BMI, and waist circumference of 27.2 kg/m2 (24.2-28.4 kg/m2) and 86.4 (80.0-94.0) cm, respectively. In total, 188 (69.4%) participants intended to use AI-assisted weight loss apps. UTAUT2 explained 63.3% of the variance in our intention of the sample to use AI-assisted weight management apps with satisfactory model fit: CMIN/df = 1.932, GFI = 0.966, AGFI = 0.954, NFI = 0.909, CFI = 0.954, RMSEA = 0.059, SRMR = 0.050. Only performance expectancy, hedonic motivation, and the habit of using AI-assisted apps were significant predictors of intention. Comparison with existing literature revealed vast variabilities in the determinants of AI- and non-AI weight loss app acceptability in adults with and without overweight and obesity. UTAUT2 produced a good fit in explaining the acceptability of AI-assisted apps among a multi-ethnic, developed, southeast Asian sample with overweight and obesity.

Conclusion

UTAUT2 model is recommended to guide the development of AI-assisted weight management apps among people with overweight and obesity.

Anthropometric and cardiometabolic effects of polyphenols in people with overweight and obesity: an umbrella review

CONTEXT

Polyphenols are plant-based compounds with potential anti-inflammatory, antioxidant, and anti-obesogenic properties. However, their effects on health outcomes remain unclear.

OBJECTIVE

To evaluate the effects of polyphenols on anthropometric and cardiometabolic markers.

DATA SOURCES

Six electronic databases-namely, EMBASE, CINAHL, PubMed, Scopus, The Cochrane Library (reviews only), and Web of Science-were searched for relevant systematic reviews with meta-analyses (SRMAs).

DATA EXTRACTION

Three reviewers performed the data extraction via a data-extraction Microsoft Excel spreadsheet.

DATA ANALYSIS

An umbrella review and meta-analysis of existing SRMAs was conducted. Eighteen SRMAs published from 2015 to 2023, representing 445 primary studies and 838 unique effect sizes, were identified. Meta-analyses were conducted using random-effects models with general inverse variance. Polyphenol-containing foods were found to significantly improve weight (-0.36 kg; 95% confidence interval [CI]: -0.62, 0.77 kg; P < 0.01, I2 = 64.9%), body mass index (-0.25 kg/m2; 95% CI: -0.34, -0.17 kg/m2; P < 0.001, I2 = 82.4%), waist circumference (-0.74 cm; 95% CI: -1.34, -0.15 cm; P < 0.01, I2 = 99.3%), low-density-lipoprotein cholesterol (-1.75 mg/dL; 95% CI: -2.56, -0.94; P < 0.001, I2 = 98.6%), total cholesterol (-1.23 mg/dL; 95% CI: -2.00, -0.46; P = 0.002, I2 = 94.6%), systolic blood pressure (-1.77 mmHg; 95% CI: -1.77, -0.93 mmHg; P < 0.001, I2 = 72.4%), diastolic blood pressure (-1.45 mmHg; 95% CI: -2.09, -0.80 mmHg; P < 0.001, I2 = 61.0%), fat percentage (-0.70%; 95% CI: -1.03, -0.36%; P < 0.001, I2 = 52.6%), fasting blood glucose (-0.18 mg/dL; 95% CI: -0.35, -0.01 mg/dL; P = 0.04, I2 = 62.0%), and C-reactive protein (CRP; including high-sensitivity-CRP [hs-CRP]) (-0.2972 mg/dL; 95% CI: -0.52, -0.08 mg/dL; P = 0.01, I2 = 87.9%). No significant changes were found for high-density-lipoprotein cholesterol (-0.12 mg/dL; 95% CI: -1.44, 0.69; P = 0.67, I2 = 89.4%) and triglycerides (-1.29 mg/dL; 95% CI: -2.74, 0.16; P = 0.08, I2 = 85.4%). Between-study heterogeneity could be explained by polyphenol subclass differences.

CONCLUSION

The findings of this umbrella review support the beneficial effects of polyphenols on anthropometric and metabolic markers, but discretion is warranted to determine the clinical significance of the magnitude of the biomarker improvements.

SYSTEMATIC REVIEW REGISTRATION

International Prospective Register of Systematic Reviews no. CRD42023420206.

Single-incision transgastric resection for gastric gastrointestinal stromal tumors in anatomically challenging locations

Surgical resection is the mainstay treatment for resectable gastrointestinal stromal tumors (GISTs). However, resection in anatomically challenging locations, such as near the gastroesophageal junction, lesser curve and fundus, remain technically challenging. We herein report the outcomes of the largest series of patients who underwent single-incision transgastric resection of an intraluminal gastric GIST. Our reduced-port resection technique for intraluminal GISTs in these anatomically challenging locations involves a single incision in the left hypochondrium, deepened to access the gastric lumen, with the surgery completed in a transgastric manner. A total of 22 patients received surgery with this technique at the National University Hospital in Singapore from November 2012 to September 2020. The median operative time was 101 (range 50-253) min, with no conversions to open surgery, median lesion size 3.6 (range 1.8-8.2) cm and median postoperative length of stay 5 (range 1-13) days. There was no 30-day mortality and no recurrence during the follow-up period. Our laparoscopic approach for reduced-port transgastric excision of intraluminal GISTs allows for adequate surgical clearance, convenient extraction and secure gastrostomy closure with low morbidity.

Bariatric Evaluation Through AI: a Survey of Expert Opinions Versus ChatGPT-4 (BETA-SEOV)

BACKGROUND

Recent advancements in artificial intelligence, such as OpenAI's ChatGPT-4, are revolutionizing various sectors, including healthcare. This study investigates the use of ChatGPT-4 in identifying suitable candidates for bariatric surgery and providing surgical recommendations to improve decision-making in obesity treatment amid the global obesity epidemic.

METHODS

We devised ten patient scenarios, thoughtfully encompassing a spectrum that spans from uncomplicated cases to more complex ones. Our objective was to delve into the decision-making process regarding the recommendation of bariatric surgery. From July 29th to August 10th, 2023, we conducted a voluntary online survey involving thirty prominent bariatric surgeons, ensuring that there was no predetermined bias in the selection of a specific type of bariatric surgery. This survey was designed to collect their insights on these scenarios and gain a deeper understanding of their professional experience and background in the field of bariatric surgery. Additionally, we consulted ChatGPT-4 in two separate conversations to evaluate its alignment with expert opinions on bariatric surgery options.

RESULTS

In 40% of the scenarios, disparities were identified between the two conversations with ChatGPT-4. It matched expert opinions in 30% of cases. Differences were noted in cases like gastrointestinal metaplasia and gastric adenocarcinoma, but there was alignment with conditions like endometriosis and GERD.

CONCLUSION

The evaluation of ChatGPT-4's role in determining bariatric surgery suitability uncovered both potential and shortcomings. Its alignment with experts was inconsistent, and it often overlooked key factors, emphasizing human expertise's value. Its current use requires caution, and further refinement is needed for clinical application.

Natural mutations of human XDH promote the nitrite (NO2-)-reductase capacity of xanthine oxidoreductase: A novel mechanism to promote redox health?

Several rare genetic variations of human XDH have been shown to alter xanthine oxidoreductase (XOR) activity leading to impaired purine catabolism. However, XOR is a multi-functional enzyme that depending upon the environmental conditions also expresses oxidase activity leading to both O2·- and H2O2 and nitrite (NO2-) reductase activity leading to nitric oxide (·NO). Since these products express important, and often diametrically opposite, biological activity, consideration of the impact of XOR mutations in the context of each aspect of the biochemical activity of the enzyme is needed to determine the potential full impact of these variants. Herein, we show that known naturally occurring hXDH mutations do not have a uniform impact upon the biochemical activity of the enzyme in terms of uric acid (UA), reactive oxygen species (ROS) and nitric oxide ·NO formation. We show that the His1221Arg mutant, in the presence of xanthine, increases UA, O2·- and NO generation compared to the WT, whilst the Ile703Val increases UA and ·NO formation, but not O2·-. We speculate that this change in the balance of activity of the enzyme is likely to endow those carrying these mutations with a harmful or protective influence over health that may explain the current equipoise underlying the perceived importance of XDH mutations. We also show that, in presence of inorganic NO2-, XOR-driven O2·- production is substantially reduced. We suggest that targeting enzyme activity to enhance the NO2--reductase profile in those carrying such mutations may provide novel therapeutic options, particularly in cardiovascular disease.

Foregut bypass vs. restrictive bariatric procedures for nonalcoholic fatty liver disease: a meta-analysis of 3,355 individuals

Background

Bariatric surgery represents an important treatment option for severely obese patients with nonalcoholic fatty liver disease (NAFLD). However, there remains inadequate data regarding the effects of different bariatric procedures on various NAFLD parameters, especially for histological outcomes. Thus, this meta-analysis aimed to compare the effects of restrictive bariatric procedures and foregut bypass on the metabolic, biochemical, and histological parameters for patients with NAFLD.

Methods

Medline and Embase were searched for articles relating to bariatric procedures and NAFLD. Pairwise meta-analysis was conducted to compare efficacy of bariatric procedures pre- vs. post-procedure with subgroup analysis to further compare restrictive against foregut bypass procedures.

Results

Thirty-one articles involving 3,355 patients who underwent restrictive bariatric procedures (n=1,460) and foregut bypass (n=1,895) were included. Both foregut bypass (P<0.01) and restrictive procedures (P=0.03) significantly increased odds of fibrosis resolution. Compared to restrictive procedures, foregut bypass resulted in a borderline non-significant decrease in fibrosis score (P=0.06) and significantly lower steatosis score (P<0.001). For metabolic parameters, foregut bypass significantly lowered body mass index (P=0.003) and low-density lipoprotein (P=0.008) compared to restrictive procedures. No significant differences were observed between both procedures for aspartate aminotransferase (P=0.17) and alkaline phosphatase (P=0.61). However, foregut bypass resulted in significantly lower gamma-glutamyl transferase than restrictive procedures (P=0.01) while restrictive procedures resulted in significantly lower alanine transaminase than foregut bypass (P=0.02).

Conclusions

The significant histological and metabolic advantages and comparable improvements in biochemical outcomes support the choice of foregut bypass over restrictive bariatric procedures in NAFLD management.

The impact of value-driven outcomes initiative on endo-laparoscopic groin hernia repair

PURPOSE

Value driven outcome (VDO) initiative is a value-based, patient-focused tool which utilizes a clinical outcome-based approach to optimize value of care based on clinically relevant quality indicators and costs required to achieve the care. In this study, we evaluate the impact of a VDO initiative on groin hernia repair, a commonly performed elective surgery in our hospital.

METHODS

A VDO initiative was implemented in 2019 to encourage elective inguinal hernia repair to be performed at a day surgery setting. A comparison of outcomes was made between hernia surgeries performed in 2019 with those in 2020 and 2021. Pre-defined criteria were used to select patients that can be operated at a day surgery setting. Patients' expectations were addressed preoperatively about day surgery procedure and postoperative recovery. Day surgery bundles were used to standardize pre- and post-surgery protocols. Pain control was optimized using a specialized local anesthesia regime.

RESULTS

A total of 263 laparoscopic hernia surgeries were performed between May 2019 and December 2021. After implementation of VDO initiative, the percentage of patients discharged within 24 h increased from 78% in year 2019 to 97% in year 2020 and 99% in year 2021. Conversion rate for day surgery to short stay decreased from 9% in year 2019 to 1% in year 2020 and 2% in year 2021. In 2019 to 2021, there were no 30-day readmission, no hernia recurrence in 90 days, no conversion to open surgery.

CONCLUSION

VDO initiative is a promising tool to deliver better value-based care for patients undergoing endo-laparoscopic inguinal hernia repair.

Socio-Demographic, Behavioral and Psychological Factors Associated with High BMI among Adults in a Southeast Asian Multi-Ethnic Society: A Structural Equation Model

While various influencing factors of overweight and obesity have been identified, the underlying mechanism remains unclear. We examined the relationships among sociodemographic, behavioral, and psychological factors on anthropometry in a multi-ethnic population with overweight and obesity. Participants (N = 251) were recruited from January to October 2022. Mean age and self-reported BMI were 31.7 ± 10.1 years and 29.2 ± 7.2 kg/m². Participants were mostly female (52.4%) and overweight (58.2%). Multivariate multiple regression was performed using maximum likelihood estimation. Body mass index was associated with waist circumference, age, sex, race, marital status, education level, residential region, overeating habit, immediate thinking, self-regulation, and physical activity, but not anxiety, depression, or the intention to change eating habits. Final model indicated good fit: χ² (30, N = 250) = 33.5, p = 0.32, CFI = 0.993, TLI = 0.988, RMSEA = 0.022, and SRMR = 0.041. Direct effects were found between BMI and overeating (β = 0.10, p = 0.004), race (β = -0.82, p < 0.001), marital status (β = -0.42, p = 0.001), and education level (β = -0.28, p = 0.019). Crisps (68.8%), cake (66.8%) and chocolate (65.6%) were identified as the most tempting foods. Immediate thinking indirectly increased overeating habits through poor self-regulation, although sociodemographic characteristics better predicted anthropometry than psycho-behavioral constructs.

A141 DUPILUMAB IMPROVES CLINICAL, SYMPTOMATIC, ENDOSCOPIC, AND HISTOLOGIC ASPECTS OF EOE, REGARDLESS OF PRIOR SWALLOWED TOPICAL STEROID USE

Background

Swallowed topical corticosteroids (STC) are a first-line treatment for eosinophilic esophagitis (EoE) but are not uniformly effective. Dupilumab (DPL), a fully human monoclonal antibody, blocks the shared receptor component for IL-4/IL-13, key and central drivers of type 2 inflammation. In Parts A and B of the phase 3 LIBERTY-EoE-TREET (NCT03633617) study, weekly DPL 300mg improved clinical, symptomatic, histologic, and endoscopic aspects of EoE and was generally well tolerated in adult and adolescent patients (pts) with EoE.

Purpose

To assess the efficacy of weekly DPL 300mg vs placebo (PBO) at Week 24 in pts from Parts A and B with/without prior history of STC use, and from Part B with/without a history of inadequate response, intolerance, or contraindication to STCs.

Method

Pts who received STCs for EoE within 8 weeks prior to baseline were excluded from the study. Co-primary endpoints at Week 24 were the proportion achieving peak eosinophil count (PEC) ≤6/high-power field (hpf) and the absolute change in Dysphagia Symptom Questionnaire (DSQ) score. Other secondary endpoints at Week 24 included: % change in PEC; absolute change in Histologic Scoring System (HSS) grade and stage scores and Endoscopic Reference Score (EREFS); % change in DSQ score.

Result(s)

At baseline, in Parts A and B combined, 84/122 (69%) and 87/118 (74%) of DPL- and PBO-treated pts had history of STC use. For pts treated with DPL vs PBO PEC≤6/hpf was achieved by 59.5% vs 3.4% of pts with, and 57.9% vs 12.9% without, prior STC use. Difference vs PBO (95% CI) in the absolute change in DSQ score was −13.27 (−18.03, −8.50) vs −5.21 (−12.41, 2.00) for pts with/without prior STC use. Difference vs PBO (95% CI) for pts with/without prior STC use were: % change in PEC −80.76 (−97.77, −63.75)/−84.87 (−112.16, −57.58); absolute change in EoE-HSS grade −0.77 (−0.87, −0.66)/−0.57 (−0.77, −0.38) and stage −0.77 (−0.87, −0.66)/−0.55 (−0.73, −0.36); absolute change in EREFS −3.86 (−4.70, −3.02)/−2.59 (−4.16, −1.02); % change in DSQ −34.5 (−47.75, −21.22)/-14.9 (−35.21, 5.36). DPL was generally well tolerated in the intent-to-treat population; the most common TEAEs for DPL/PBO were injection-site reactions (37.7/33.3%). In Part B, 38/80 (48%) and 39/79 (49%) of DPL- and PBO-treated pts had inadequate response/intolerance/contraindication to STCs. For DPL vs PBO PEC≤6/hpf was achieved by 55.3% vs 7.7% with, and 61.9% vs 5.0% of pts without, inadequate response/intolerance/contraindication to STC. Difference vs PBO (95% CI) for absolute change in DSQ score was −11.55 (−19.06, −4.04)/−7.08 (−13.75, −0.42) for pts with/without inadequate response/intolerance/contraindication to STCs.

Conclusion(s)

Conclusion: Regardless of prior STC use, in this pooled analysis from Part A and Part B of the EoE TREET Phase 3 Study, weekly DPL 300mg demonstrated substantial improvements in clinical, histologic, and endoscopic study endpoints at Week 24 in adults and adolescents with EoE.

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Research sponsored by Sanofi and Regeneron Pharmaceuticals, Inc.

Disclosure of Interest

A. Bredenoord Shareholder of: SST, Grant / Research support from: Bayer, Nutricia, SST, Consultant of: Arena Pharmaceuticals, AstraZeneca, Calypso Biotech, Dr Falk, EsoCap, Gossamer Bio, Laborie, Medtronic, RB Pharma, Regeneron Pharmaceuticals, Inc., Robarts Clinical Trials, E. Dellon Grant / Research support from: Research funding; Adare Pharma Solutions, Allakos, GSK, Meritage Pharma, Miraca Life Sciences, Nutricia, Receptos/BMS, Regeneron Pharmaceuticals, Inc., Shire. Educational grant; Allakos, Banner Pharmaceuticals, Holoclara, Consultant of: Abbott, Adare Pharma Solutions, Aimmune Therapeutics, Alivio Therapeutics, Allakos, Arena Pharmaceuticals, AstraZeneca, Banner Pharmaceuticals, Biorasi, Calypso Biotech, Enumeral, EsoCap, Gossamer Bio, GSK, Receptos/BMS, Regeneron Pharmaceuticals, Inc., Robarts Clinical Trials, Salix Pharmaceuticals, Shire/Takeda, A. Lucendo Grant / Research support from: Dr Falk, Regeneron Pharmaceuticals, Inc., Consultant of: Dr Falk, EsoCap, M. Collins Grant / Research support from: Receptos/BMS, Regeneron Pharmaceuticals, Inc., Shire, Consultant of: Allakos, AstraZeneca, BMS, EsoCap, Regeneron Pharmaceuticals, Inc., Shire, A. Khodzhayev Shareholder of: Regeneron Pharmaceuticals, Inc., Employee of: Regeneron Pharmaceuticals, Inc., X. Sun Shareholder of: Regeneron Pharmaceuticals, Inc., Employee of: Regeneron Pharmaceuticals, Inc., K. Patel Employee of: Sanofi, B. Beazley Shareholder of: Regeneron Pharmaceuticals, Inc., Employee of: Regeneron Pharmaceuticals, Inc., A. Shabbir Shareholder of: Regeneron Pharmaceuticals, Inc., Employee of: Regeneron Pharmaceuticals, Inc.

Malignant ascites as a marker of peritoneal carcinomatosis burden in patients with colorectal and gastroesophageal cancer

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Background: Malignant ascites occurs frequently in patients with gastric cancer (GC) and colorectal cancer (CRC) with peritoneal metastasis (PM). The presence of PM and malignant ascites have been independently reported to confer resistance to systemic therapy and poorer prognosis. However, the occurrence of malignant ascites as a function of increasing peritoneal carcinomatosis burden has been less studied and reported. Methods: We reviewed prospective cohorts of gastric cancer and colorectal cancer patients with PM. The first cohort was a prospective group of GCPM patients receiving bi-directional systemic and peritoneal-directed therapies (catheter-based intraperitoneal chemotherapy and/or pressurized intraperitoneal aerosol chemotherapy respectively) at a tertiary oncology center in Singapore. Clinico-pathological data, including Peritoneal Cancer Index (PCI) and the presence or absence of ascites based on diagnostic laparoscopy, was collected. To orthogonally validate the hypothesis of malignant ascites as a function of peritoneal carcinomatosis burden in gastrointestinal malignancies, we studied the relationship between ascites, PM and survival in an independent cohort of metastatic CRC patients eligible for first-line systemic treatment enrolled in two randomized clinical trials in different Italian cancer centers. Results: In the first cohort of 82 patients with GCPM, the median PCI was 19 (inter-quartile range (IQR) 8 – 26) in the group with ascites and 3 (IQR 1 – 12) in the group without ascites (p=0.005), suggesting ascites occurs with higher PM burden. The median overall survival (OS) was poorer in patients with ascites (13.4 vs 16.4 months, HR 1.6, 95% CI 0.9 – 2.8, p=0.082). The median OS in patients with PCI of <7 was 17.3 months (95% 12.0 – 22.7) and 13.8 months (95% CI 11.0 – 16.6) in those with PCI score >7. In the validation cohort of 900 CRC patients, presence of malignant ascites and PM resulted in poorer survival compared to patients with PM and no malignant ascites (HR for OS PM with ascites vs PM without ascites 2.01 (95% CI 1.37 - 2.96), p<0.001). Interestingly, those with PM and ascites had a poorer survival to those with stage IV disease without peritoneal involvement, while those with PM without ascites did not have a statistically significant difference (PM with malignant ascites vs. no peritoneal disease, HR for OS 2.14, 95% CI 1.57 – 3.01, p=0.007; PM without ascites vs no peritoneal disease, HR for OS 1.10, 95% CI 0.91 – 1.34). Conclusions: Our study of patients with colorectal or gastric cancer and peritoneal metastases suggest the presence of malignant ascites as a function of increased peritoneal carcinomatosis burden among patients with metastatic gastrointestinal malignancies, with correspondingly poorer survival outcomes.

Original article: The prognostic value of including non-alcoholic fatty liver disease in the definition of metabolic syndrome

BACKGROUND/AIMS

Metabolic syndrome (MetS) affects over one third of the US adult population. Despite its close association with non-alcoholic fatty liver disease (NAFLD), the traditional definition of MetS does not account for the presence of NAFLD. The present study thus aims to evaluate the inclusion of NAFLD in the diagnostic criteria of metabolic syndrome on its accuracy of capturing individuals with metabolic dysregulation and its prediction of adverse events.

METHODS

Data collected from NHANES between 1999 and 2018 was analysed. Clinical characteristics and outcomes between individuals with metabolic syndrome from both the American Heart Association/National Heart, Lung, and Blood Institute (MetS) and the study's proposed diagnostic criteria (MetS2) were evaluated. Outcomes in both groups were evaluated with multivariate analyses, and further subgroup analysis on individuals matched with Coarsened Exact Matching was performed.

RESULTS

Of 46,184 individuals included, 32.54% and 40.54% fulfilled MetS and MetS2 criteria respectively. Considering NAFLD in the definition of metabolic syndrome, a further 8.00% (n = 3694) were included. MetS was significantly associated with all-cause (HR: 1.184, 95% CI: 1.110-1.263, p < 0.001) and cardiovascular disease (CVD) mortality (SHR: 1.288, 95% CI: 1.233-1.347, p < 0.001), and major adverse cardiovascular events (MACE). MetS2 was similarly associated with all-cause (HR: 1.175, 95% CI: 1.088-1.269, p < 0.001), CVD mortality (SHR: 1.283, 95% CI: 1.245-1.323, p < 0.001) and MACE.

CONCLUSION

Inclusion of NAFLD allows for identification a greater proportion of the population with metabolic risk. This allows for early intervention and potential to lift some burden off the global healthcare system.

Essential elements of weight loss apps for a multi-ethnic population with high BMI: a qualitative study with practical recommendations

Smartphone weight loss apps are constantly being developed but the essential elements needed by a multi-ethnic population with overweight and obesity remains unclear. Purpose: To explore the perceptions of an Asian multi-ethnic population with overweight and obesity on the essential elements of weight loss apps. Twenty two participants were purposively sampled from a specialist weight management clinic in Singapore from 13 April to 30 April 2021. Recorded interviews were conducted using face-to-face and videoconferencing modalities. Data saturation was reached at the 18th participant. Data analysis was performed using inductive content analysis with constant comparison between and within transcripts. Findings: Three themes and eight subthemes on the essential app components emerged-(a) comprehensive and flexible calorie counters; (b) holistic, gradual and individualized behavior change recommendations tailored for people with overweight and obesity, and (c) just-in-time reminders of future consequences. There was a need to incorporate flexible options for food logging; break down general recommendations into small steps towards sustainable changes; tailor app contents for people with overweight and obesity; and evoke one's considerations of future consequences. Future weight loss apps should be designed to meet the needs of those with overweight and obesity, the very population that needs assistance with weight loss. Future apps could consider leveraging the capacity of artificial intelligence to provide personalized weight management in terms of sustaining self-regulation behaviors, optimizing goal-setting and providing personalized and timely recommendations for weight loss.

The placebo response rate and nocebo events in obesity pharmacological trials. A systematic review and meta-analysis

BACKGROUND

There is a growing number of trials examining the effectiveness of pharmacotherapies for obesity, however, little is known about placebo and nocebo effect in these trials. Hence, we sought to examine the effect of placebo in obesity trials, to better understand the potential factors affecting clinical endpoints in them.

METHODS

Medline, Embase, and Cochrane CENTRAL were searched for articles examining weight-loss RCTs examining patients with overweight or obesity in placebo-controlled arms from inception till 25 June 2022. This paper was registered online with PROSPERO (CRD42022302482). A single arm meta-analysis of proportions was used to estimate the primary outcomes, ≥5%, ≥10%, and ≥15% total weight loss - and the adverse effects that patients experienced during the trial. A meta-analysis of means was used to estimate the pooled mean differences of the secondary outcomes including, body weight measurements, lipid levels, glycemic indices, and blood pressure over time.

FINDINGS

A total of 63 papers involving 20,454 patients and 69 trials were included. The proportion of patients that had ≥5%, ≥10%, and ≥15% weight loss was 20·4% (CI:16·1% to 25·0%), 8·3% (CI:6·1% to 10·9%), and 6·2% (CI:3·8% to 9·7%), respectively. Analysis by duration of trials showed stepwise increase in proportion of patients with ≥5% and ≥10% weight loss with increasing duration of study. Analysis of secondary outcomes found modest improvement in all analyses. The pooled average rate of overall AEs, serious AEs, and discontinuation was 73·7% (CI:68·0% to 79·0%), 3·4% (CI:2·4% to 4·5%), and 5·2% (CI:4·0% to 6·5%), respectively. In psychiatric complications, the pooled rates of anxiety and depression were 2·7% (CI:1·8% to 3·7%) and 2·5 (CI:1·7% to 3·3%).

INTERPRETATION

Our meta-analysis of placebo-treated participants in weight-loss RCTs indicate a significant placebo and nocebo effect. These findings are important to quantify their effect and may inform the design of future RCTs.

FUNDING

This research did not receive additional support from organizations beyond the authors' academic institutions.

Outcomes of a Phase II Study of Intraperitoneal Paclitaxel plus Systemic Capecitabine and Oxaliplatin (XELOX) for Gastric Cancer with Peritoneal Metastases

BACKGROUND

Adding intraperitoneal paclitaxel (IP-PTX) to paclitaxel/5-fluoropyrimidine has shown promising results in patients with gastric cancer peritoneal metastases (GCPM) but has not been studied with standard-of-care platinum/fluoropyrimidine combinations. Our goal to was evaluate IP-PTX with capecitabine/oxaliplatin (XELOX) in GCPM.

METHODS

Forty-four patients with GCPM received IP PTX (40 mg/m², Days 1, 8), oral capecitabine (1000 mg/m² twice daily, Days 1-14) and intravenous oxaliplatin (100 mg/m², Day 1) in 21-day cycles. Patients with synchronous GCPM underwent conversion surgery if they had good response after chemotherapy, conversion to negative cytology, no extraperitoneal metastasis, and no peritoneal disease during surgery. The primary endpoint was overall survival and secondary endpoints were progression-free survival and safety. Outcomes from the trial were compared against a matched cohort of 39 GCPM patients who received systemic chemotherapy (SC) comprising platinum/fluoropyrimidine.

RESULTS

The median OS for the IP and SC groups was 14.6 and 10.6 months (hazard ratio [HR] 0.44; 95% confidence interval [CI], 0.26-0.74; p = 0.002). The median PFS for the IP and SC group was 9.5 and 4.4 months respectively (HR 0.39; 95% CI 0.25-0.66; p < 0.001). Patients in the SC group were younger (IP vs. SC, 61 vs. 56 years, p = 0.021) and had better performance status (ECOG 0, IP vs. SC, 47.7% vs. 76.9%, p = 0.007) compared with the IP cohort. In IP group, conversion surgery was performed in 36.1% (13/36) of patients, with a median OS of 24.2 (95% CI 13.1-35.3) months and 1-year OS of 84.6%.

CONCLUSIONS

IP PTX with XELOX is a promising treatment option for GCPM patients. In patients with good response, conversion surgery was feasible with favourable outcomes.

The influence of anastomotic techniques on postoperative anastomotic complications: Results of the Oesophago-Gastric Anastomosis Audit

BACKGROUND

The optimal anastomotic techniques in esophagectomy to minimize rates of anastomotic leakage and conduit necrosis are not known. The aim of this study was to assess whether the anastomotic technique was associated with anastomotic failure after esophagectomy in the international Oesophago-Gastric Anastomosis Audit cohort.

METHODS

This prospective observational multicenter cohort study included patients undergoing esophagectomy for esophageal cancer over 9 months during 2018. The primary exposure was the anastomotic technique, classified as handsewn, linear stapled, or circular stapled. The primary outcome was anastomotic failure, namely a composite of anastomotic leakage and conduit necrosis, as defined by the Esophageal Complications Consensus Group. Multivariable logistic regression modeling was used to identify the association between anastomotic techniques and anastomotic failure, after adjustment for confounders.

RESULTS

Of the 2238 esophagectomies, the anastomosis was handsewn in 27.1%, linear stapled in 21.0%, and circular stapled in 51.9%. Anastomotic techniques differed significantly by the anastomosis sites (P < .001), with the majority of neck anastomoses being handsewn (69.9%), whereas most chest anastomoses were stapled (66.3% circular stapled and 19.3% linear stapled). Rates of anastomotic failure differed significantly among the anastomotic techniques (P < .001), from 19.3% in handsewn anastomoses, to 14.0% in linear stapled anastomoses, and 12.1% in circular stapled anastomoses. This effect remained significant after adjustment for confounding factors on multivariable analysis, with an odds ratio of 0.63 (95% CI, 0.46-0.86; P = .004) for circular stapled versus handsewn anastomosis. However, subgroup analysis by anastomosis site suggested that this effect was predominantly present in neck anastomoses, with anastomotic failure rates of 23.2% versus 14.6% versus 5.9% for handsewn versus linear stapled anastomoses versus circular stapled neck anastomoses, compared with 13.7% versus 13.8% versus 12.2% for chest anastomoses.

CONCLUSIONS

Handsewn anastomoses appear to be independently associated with higher rates of anastomotic failure compared with stapled anastomoses. However, this effect seems to be largely confined to neck anastomoses, with minimal differences between techniques observed for chest anastomoses. Further research into standardization of anastomotic approach and techniques may further improve outcomes.

Comparison of mechanistic pathways of bariatric surgery in patients with diabetes mellitus: A Bayesian network meta-analysis

OBJECTIVE

Metabolic bariatric procedures are potentially efficacious treatment options in patients with type 2 diabetes mellitus (T2DM). Previous meta-analyses focused on individual operative approaches rather than the mechanistic pathways behind different bariatric procedures. This updated network meta-analysis aimed to synthesize new evidence and comparatively evaluate the efficacy of metabolic surgery against restrictive procedures and standard first-line treatment for patients with T2DM.

METHODS

Embase, MEDLINE, and trial registries were searched for randomized controlled trials on bariatric surgeries in patients with T2DM on September 3, 2021. A Bayesian network meta-analysis was conducted. The primary outcome was T2DM remission. Secondary outcomes included changes in BMI, lipoprotein levels, and blood pressure.

RESULTS

Thirty-two articles were included. Metabolic surgery was statistically superior to restrictive procedures (risk ratio [RR]: 2.57, 95% credibility intervals [CrI]: 1.36-5.43), medical therapy (RR: 35.29, 95% Crl: 10.56-183.23), and lifestyle intervention (RR: 40.51, 95% Crl: 5.32-402.59) in T2DM remission. Metabolic surgery significantly lowered BMI and blood pressure compared with other interventions. Restrictive procedures significantly increased high-density lipoprotein compared with metabolic surgery. Lifestyle intervention and metabolic surgery were statistically superior to restrictive procedures in reducing low-density lipoprotein.

CONCLUSIONS

The superiority in diabetes remission and favorable metabolic profile support the choice of metabolic surgery over restrictive bariatric procedures.

Patient Selection in One Anastomosis/Mini Gastric Bypass-an Expert Modified Delphi Consensus

PURPOSE

One anastomosis/mini gastric bypass (OAGB/MGB) is up to date the third most performed obesity and metabolic procedure worldwide, which recently has been endorsed by ASMBS. The main criticisms are the risk of bile reflux, esophageal cancer, and malnutrition. Although IFSO has recognized this procedure, guidance is needed regarding selection criteria. To give clinicians a daily support in performing the right patient selection in OAGB/MGB, the aim of this paper is to generate clinical guidelines based on an expert modified Delphi consensus.

METHODS

A committee of 57 recognized bariatric surgeons from 24 countries created 69 statements. Modified Delphi consensus voting was performed in two rounds. An agreement/disagreement among ≥ 70.0% of the experts was considered to indicate a consensus.

RESULTS

Consensus was achieved for 56 statements. Remarkably, ≥ 90.0% of the experts felt that OAGB/MGB is an acceptable and suitable option "in patients with Body mass index (BMI) > 70, BMI > 60, BMI > 50 kg/m² as a one-stage procedure," "as the second stage of a two-stage bariatric surgery after Sleeve Gastrectomy for BMI > 50 kg/m² (instead of BPD/DS)," and "in patients with weight regain after restrictive procedures. No consensus was reached on the statement that OAGB/MGB is a suitable option in case of resistant Helicobacter pylori. This is likely as there is a concern that this procedure is associated with reflux and its related long-term complications including risk of cancer in the esophagus or stomach. Also no consensus reached on OAGB/MGB as conversional surgery in patients with GERD after restrictive procedures. Consensus for disagreement was predominantly achieved "in case of intestinal metaplasia of the stomach" (74.55%), "in patients with severe Gastro Esophageal Reflux Disease (GERD)(C,D)" (75.44%), "in patients with Barrett's metaplasia" (89.29%), and "in documented insulinoma" (89.47%).

CONCLUSION

Patient selection in OAGB/MGB is still a point of discussion among experts. There was consensus that OAGB/MGB is a suitable option in elderly patients, patients with low BMI (30-35 kg/m²) with associated metabolic problems, and patients with BMIs more than 50 kg/m² as one-stage procedure. OAGB/MGB can also be a safe procedure in vegetarian and vegan patients. Although OAGB/MGB can be a suitable procedure in patients with large hiatal hernia with concurrent hiatal hernia, it should not be offered to patients with grade C or D esophagitis or Barrett's metaplasia.

Endothelial‐immune crosstalk contributes to vasculopathy in nonalcoholic fatty liver disease

The top cause of mortality in patients with nonalcoholic fatty liver disease (NAFLD) is cardiovascular complications. However, mechanisms of NAFLD‐associated vasculopathy remain understudied. Here, we show that blood outgrowth endothelial cells (BOECs) from NAFLD subjects exhibit global transcriptional upregulation of chemokines and human leukocyte antigens. In mouse models of diet‐induced NAFLD, we confirm heightened endothelial expressions of CXCL12 in the aortas and the liver vasculatures, and increased retention of infiltrated leukocytes within the vessel walls. To elucidate endothelial‐immune crosstalk, we performed immunoprofiling by single‐cell analysis, uncovering T cell intensification in NAFLD patients. Functionally, treatment with a CXCL12‐neutralizing antibody is effective at moderating the enhanced chemotactic effect of NAFLD BOECs in recruiting CD8⁺ T lymphocytes. Interference with the CXCL12‐CXCR4 axis using a CXCR4 antagonist also averts the impact of immune cell transendothelial migration and restores endothelial barrier integrity. Clinically, we detect threefold more circulating damaged endothelial cells in NAFLD patients than in healthy controls. Our work provides insight into the modulation of interactions with effector immune cells to mitigate endothelial injury in NAFLD.

Textbook outcome following oesophagectomy for cancer: international cohort study

Background

Textbook outcome has been proposed as a tool for the assessment of oncological surgical care. However, an international assessment in patients undergoing oesophagectomy for oesophageal cancer has not been reported. This study aimed to assess textbook outcome in an international setting.

Methods

Patients undergoing curative resection for oesophageal cancer were identified from the international Oesophagogastric Anastomosis Audit (OGAA) from April 2018 to December 2018. Textbook outcome was defined as the percentage of patients who underwent a complete tumour resection with at least 15 lymph nodes in the resected specimen and an uneventful postoperative course, without hospital readmission. A multivariable binary logistic regression model was used to identify factors independently associated with textbook outcome, and results are presented as odds ratio (OR) and 95 per cent confidence intervals (95 per cent c.i.).

Results

Of 2159 patients with oesophageal cancer, 39.7 per cent achieved a textbook outcome. The outcome parameter ‘no major postoperative complication’ had the greatest negative impact on a textbook outcome for patients with oesophageal cancer, compared to other textbook outcome parameters. Multivariable analysis identified male gender and increasing Charlson comorbidity index with a significantly lower likelihood of textbook outcome. Presence of 24-hour on-call rota for oesophageal surgeons (OR 2.05, 95 per cent c.i. 1.30 to 3.22; P = 0.002) and radiology (OR 1.54, 95 per cent c.i. 1.05 to 2.24; P = 0.027), total minimally invasive oesophagectomies (OR 1.63, 95 per cent c.i. 1.27 to 2.08; P &lt; 0.001), and chest anastomosis above azygous (OR 2.17, 95 per cent c.i. 1.58 to 2.98; P &lt; 0.001) were independently associated with a significantly increased likelihood of textbook outcome.

Conclusion

Textbook outcome is achieved in less than 40 per cent of patients having oesophagectomy for cancer. Improvements in centralization, hospital resources, access to minimal access surgery, and adoption of newer techniques for improving lymph node yield could improve textbook outcome.

Textbook outcome following oesophagectomy for cancer: international cohort study

BACKGROUND

Textbook outcome has been proposed as a tool for the assessment of oncological surgical care. However, an international assessment in patients undergoing oesophagectomy for oesophageal cancer has not been reported. This study aimed to assess textbook outcome in an international setting.

METHODS

Patients undergoing curative resection for oesophageal cancer were identified from the international Oesophagogastric Anastomosis Audit (OGAA) from April 2018 to December 2018. Textbook outcome was defined as the percentage of patients who underwent a complete tumour resection with at least 15 lymph nodes in the resected specimen and an uneventful postoperative course, without hospital readmission. A multivariable binary logistic regression model was used to identify factors independently associated with textbook outcome, and results are presented as odds ratio (OR) and 95 per cent confidence intervals (95 per cent c.i.).

RESULTS

Of 2159 patients with oesophageal cancer, 39.7 per cent achieved a textbook outcome. The outcome parameter 'no major postoperative complication' had the greatest negative impact on a textbook outcome for patients with oesophageal cancer, compared to other textbook outcome parameters. Multivariable analysis identified male gender and increasing Charlson comorbidity index with a significantly lower likelihood of textbook outcome. Presence of 24-hour on-call rota for oesophageal surgeons (OR 2.05, 95 per cent c.i. 1.30 to 3.22; P = 0.002) and radiology (OR 1.54, 95 per cent c.i. 1.05 to 2.24; P = 0.027), total minimally invasive oesophagectomies (OR 1.63, 95 per cent c.i. 1.27 to 2.08; P < 0.001), and chest anastomosis above azygous (OR 2.17, 95 per cent c.i. 1.58 to 2.98; P < 0.001) were independently associated with a significantly increased likelihood of textbook outcome.

CONCLUSION

Textbook outcome is achieved in less than 40 per cent of patients having oesophagectomy for cancer. Improvements in centralization, hospital resources, access to minimal access surgery, and adoption of newer techniques for improving lymph node yield could improve textbook outcome.

Single-Cell Atlas of Lineage States, Tumor Microenvironment, and Subtype-Specific Expression Programs in Gastric Cancer

Gastric cancer heterogeneity represents a barrier to disease management. We generated a comprehensive single-cell atlas of gastric cancer (>200,000 cells) comprising 48 samples from 31 patients across clinical stages and histologic subtypes. We identified 34 distinct cell-lineage states including novel rare cell populations. Many lineage states exhibited distinct cancer-associated expression profiles, individually contributing to a combined tumor-wide molecular collage. We observed increased plasma cell proportions in diffuse-type tumors associated with epithelial-resident KLF2 and stage-wise accrual of cancer-associated fibroblast subpopulations marked by high INHBA and FAP coexpression. Single-cell comparisons between patient-derived organoids (PDO) and primary tumors highlighted inter- and intralineage similarities and differences, demarcating molecular boundaries of PDOs as experimental models. We complemented these findings by spatial transcriptomics, orthogonal validation in independent bulk RNA-sequencing cohorts, and functional demonstration using in vitro and in vivo models. Our results provide a high-resolution molecular resource of intra- and interpatient lineage states across distinct gastric cancer subtypes.

SIGNIFICANCE

We profiled gastric malignancies at single-cell resolution and identified increased plasma cell proportions as a novel feature of diffuse-type tumors. We also uncovered distinct cancer-associated fibroblast subtypes with INHBA-FAP-high cell populations as predictors of poor clinical prognosis. Our findings highlight potential origins of deregulated cell states in the gastric tumor ecosystem. This article is highlighted in the In This Issue feature, p. 587.

Induction of Gastric Cancer by Successive Oncogenic Activation in the Corpus

BACKGROUND & AIMS

Metaplasia and dysplasia in the corpus are reportedly derived from de-differentiation of chief cells. However, the cellular origin of metaplasia and cancer remained uncertain. Therefore, we investigated whether pepsinogen C (PGC) transcript-expressing cells represent the cellular origin of metaplasia and cancer using a novel Pgc-specific CreERT2 recombinase mouse model.

METHODS

We generated a Pgc-mCherry-IRES-CreERT2 (Pgc-CreERT2) knock-in mouse model. Pgc-CreERT2/+ and Rosa-EYFP mice were crossed to generate Pgc-CreERT2/Rosa-EYFP (Pgc-CreERT2/YFP) mice. Gastric tissues were collected, followed by lineage-tracing experiments and histologic and immunofluorescence staining. We further established Pgc-CreERT2;KrasG12D/+ mice and investigated whether PGC transcript-expressing cells are responsible for the precancerous state in gastric glands. To investigate cancer development from PGC transcript-expressing cells with activated Kras, inactivated Apc, and Trp53 signaling pathways, we crossed Pgc-CreERT2/+ mice with conditional KrasG12D, Apcflox, Trp53flox mice.

RESULTS

Expectedly, mCherry mainly labeled chief cells in the Pgc-CreERT2 mice. However, mCherry was also detected throughout the neck cell and isthmal stem/progenitor regions, albeit at lower levels. In the Pgc-CreERT2;KrasG12D/+ mice, PGC transcript-expressing cells with KrasG12D/+ mutation presented pseudopyloric metaplasia. The early induction of proliferation at the isthmus may reflect the ability of isthmal progenitors to react rapidly to Pgc-driven KrasG12D/+ oncogenic mutation. Furthermore, Pgc-CreERT2;KrasG12D/+;Apcflox/flox mice presented intramucosal dysplasia/carcinoma and Pgc-CreERT2;KrasG12D/+;Apcflox/flox;Trp53flox/flox mice presented invasive and metastatic gastric carcinoma.

CONCLUSIONS

The Pgc-CreERT2 knock-in mouse is an invaluable tool to study the effects of successive oncogenic activation in the mouse corpus. Time-course observations can be made regarding the responses of isthmal and chief cells to oncogenic insults. We can observe stomach-specific tumorigenesis from the beginning to metastatic development.

Coronavirus viability in surgical plume and methods for safe disposal: a preclinical model

Smoke generated by cautery devices used during surgery may contain infective particles and may cause transmission of airborne viruses. This study determines whether live viruses are present in surgical smoke and evaluates the effectiveness of several proposed methods of removal so as to improve safety of healthcare workers.

Postoperative outcomes in oesophagectomy with trainee involvement

BACKGROUND

The complexity of oesophageal surgery and the significant risk of morbidity necessitates that oesophagectomy is predominantly performed by a consultant surgeon, or a senior trainee under their supervision. The aim of this study was to determine the impact of trainee involvement in oesophagectomy on postoperative outcomes in an international multicentre setting.

METHODS

Data from the multicentre Oesophago-Gastric Anastomosis Study Group (OGAA) cohort study were analysed, which comprised prospectively collected data from patients undergoing oesophagectomy for oesophageal cancer between April 2018 and December 2018. Procedures were grouped by the level of trainee involvement, and univariable and multivariable analyses were performed to compare patient outcomes across groups.

RESULTS

Of 2232 oesophagectomies from 137 centres in 41 countries, trainees were involved in 29.1 per cent of them (n = 650), performing only the abdominal phase in 230, only the chest and/or neck phases in 130, and all phases in 315 procedures. For procedures with a chest anastomosis, those with trainee involvement had similar 90-day mortality, complication and reoperation rates to consultant-performed oesophagectomies (P = 0.451, P = 0.318, and P = 0.382, respectively), while anastomotic leak rates were significantly lower in the trainee groups (P = 0.030). Procedures with a neck anastomosis had equivalent complication, anastomotic leak, and reoperation rates (P = 0.150, P = 0.430, and P = 0.632, respectively) in trainee-involved versus consultant-performed oesophagectomies, with significantly lower 90-day mortality in the trainee groups (P = 0.005).

CONCLUSION

Trainee involvement was not found to be associated with significantly inferior postoperative outcomes for selected patients undergoing oesophagectomy. The results support continued supervised trainee involvement in oesophageal cancer surgery.

Regulation of adipogenic differentiation and adipose tissue inflammation by interferon regulatory factor 3

Dysfunction of adipocytes and adipose tissue is a primary defect in obesity and obesity-associated metabolic diseases. Interferon regulatory factor 3 (IRF3) has been implicated in adipogenesis. However, the role of IRF3 in obesity and obesity-associated disorders remains unclear. Here, we show that IRF3 expression in human adipose tissues is positively associated with insulin sensitivity and negatively associated with type 2 diabetes. In mouse pre-adipocytes, deficiency of IRF3 results in increased expression of PPARγ and PPARγ-mediated adipogenic genes, leading to increased adipogenesis and altered adipocyte functionality. The IRF3 knockout (KO) mice develop obesity, insulin resistance, glucose intolerance, and eventually type 2 diabetes with aging, which is associated with the development of white adipose tissue (WAT) inflammation. Increased macrophage accumulation with M1 phenotype which is due to the loss of IFNβ-mediated IL-10 expression is observed in WAT of the KO mice compared to that in wild-type mice. Bone-marrow reconstitution experiments demonstrate that the nonhematopoietic cells are the primary contributors to the development of obesity and both hematopoietic and nonhematopoietic cells contribute to the development of obesity-related complications in IRF3 KO mice. This study demonstrates that IRF3 regulates the biology of multiple cell types including adipocytes and macrophages to prevent the development of obesity and obesity-related complications and hence, could be a potential target for therapeutic interventions for the prevention and treatment of obesity-associated metabolic disorders.

Non-Invasive Characterization of the Pancreas During Bariatric Surgery via Circulating Pancreatic Specific Cell-free Messenger RNA

Bariatric surgery results in sustained weight loss and improvement in glucose homeostasis. However, the lack of accessible non-invasive tools to examine molecular alterations occurring in the pancreas limits our understanding of the causes and recovery of glucose homeostasis. Here, we describe the use of a circulating cell free mRNA (cfmRNA) based multiplex qPCR assay to selectively amplify and quantify circulating pancreatic specific transcripts levels within plasma. We applied this assay to a cohort of 58 plasma samples consisting of 10 patients that tracks multiple time points including pre and post-bariatric surgery. In our targeted multiplex screen of 14 selected pancreatic specific circulating transcripts, we identified 13 pancreatic specific transcripts that can be amplified from plasma. Furthermore, when quantifying the amplicons obtained in the short-term post-surgery (2 weeks–1 month) and long-term (3–12 months), we observed a consistent reduction of circulating GCG transcripts during short term post-surgery. Across the cohort, GCG cfmRNA levels correlated significantly with common metrics of improvement following bariatric surgery such as: haemoglobin A1c levels (R: −0.41, p-value: 0.0039) and percentage of excess weight loss (R: 0.29, p-value: 0.046).

Inorganic nitrate attenuates endothelial dysfunction consequent to systemic inflammation

Introduction

Chronic cardiovascular diseases are characterised by low-grade systemic inflammation and attenuated nitric oxide (NO) bioavailability resulting in endothelial dysfunction. Inorganic nitrate augments NO bioavailability and improves markers of vascular dysfunction in patients with cardiovascular risk factors. However, the exact mechanism of this effect is uncertain.

Purpose

To determine whether inorganic nitrate supplementation alters systemic inflammation-induced endothelial dysfunction.

Methods

62 healthy male volunteers were randomised 1:1 to receive ∼8–10 mmol of dietary inorganic nitrate in beetroot juice or nitrate-free beetroot juice (placebo) once daily for 6 days. Measures of brachial artery flow-mediated dilatation (FMD), brachial blood pressure (BP), pulse wave analysis and carotid-femoral pulse wave velocity (PWV) by Vicorder were taken prior to and at 8 hours after a typhoid vaccine (to induce mild systemic inflammation). Plasma, urine and saliva samples were also collected. Clinicaltrials.gov: NCT02715635.

Results

Baseline characteristics were similar between the two groups. Inorganic nitrate significantly elevated plasma nitrite (placebo = Δ0.02±0.5 μM, inorganic nitrate = Δ0.63±1.2 μM; p=0.01) and nitrate levels (p&lt;0.0001) compared to placebo. There were significant increases in urine nitrite (p&lt;0.0001) and nitrate (p&lt;0.0001) in addition to salivary nitrite (p&lt;0.0001) and nitrate (p&lt;0.0001) compared to placebo. After 8 hours, typhoid vaccine induced an increase in circulating white cells (placebo = Δ3.34±3.37x109/L, inorganic nitrate = Δ2.9±2.78x109/L; p=0.58) that was similar in in both arms. However, there was a significant reduction in the FMD response in the placebo group at 8-hours post vaccine; an effect that was absent in volunteers treated with inorganic nitrate (placebo = Δ−1.33±1.53%, inorganic nitrate = Δ−0.07±1.84%, p=0.005). Importantly, there were no statistically significant differences in baseline vessel diameter (p=0.78), time to peak diameter in response to flow (p=0.87) and peak shear rate (p=0.57) between the groups. When comparing change from baseline to 8 hours after the vaccine, there were no significant differences in brachial systolic BP (p=0.12), central systolic BP (p=0.12) and PWV (p=0.60) between groups, but a significant reduction in brachial diastolic BP in the inorganic nitrate group (p=0.048).

Conclusions

Inflammation-induced endothelial dysfunction was prevented in those receiving dietary inorganic nitrate suggesting that elevating circulating nitrite and delivering NO to the blood vessel wall, through dietary approaches may offer potential therapeutic benefit in those cardiovascular diseases which typically exhibit low grade inflammation and deficiencies in bioavailable NO.

Funding Acknowledgement

Type of funding sources: Public Institution(s). Main funding source(s): British Heart Foundation

Inorganic nitrate attenuates the systemic inflammatory response in typhoid vaccine-induced endothelial dysfunction in healthy volunteers

Background

Inflammatory responses underlie the development of endothelial dysfunction in CVD, however, therapeutics that might target this pathway have not been forthcoming. A key pathogenic mechanism mediating endothelial dysfunction is a reduction in bioavailable (eNOS-derived) nitric oxide (NO). Activation of the non-canonical pathway for in-vivo NO generation might offer an approach to improve NO levels and recover vascular function in pre-clinical models of CVD. Whether this might occur in humans is unknown.

Purpose

We hypothesize that consumption of inorganic nitrate will lead to increases in bioavailable NO and thus attenuate the inflammatory pathways leading to typhoid vaccine-induced endothelial dysfunction in healthy volunteers.

Methods

Healthy male volunteers were recruited (n=78) and randomized to receive either beetroot juice containing 8–10mmol nitrate or placebo (nitrate-deplete) juice once daily for 6 days. Participants underwent serial measurements of BP, FMD and GTN-induced brachial artery dilatation, and haematology and biochemistry, before and after typhoid vaccination. Blood, urine and saliva nitrite and nitrate were quantified using ozone chemiluminescence, and leukocyte flow cytometry analysis was conducted.

Results

8-hours post-vaccine endothelial function was depressed in placebo-treated volunteers, however this was prevented in nitrate-treated volunteers. This dysfunction was due to impaired endothelial function since responses to GTN were unaffected either by vaccination or dietary intervention (p=0.981). Dietary nitrate resulted in an increase in plasma (p&lt;0.0001), urine (p=0.0006) and saliva (p&lt;0.0001) nitrate, and urine (p=0.0354) and saliva (p&lt;0.0001) nitrite levels. There was a reduction in the proportions of CD14++/CD16+intermediate monocytes in nitrate-treated participants after vaccine (p=0.016, change from baseline between groups). In the nitrate-treated group, less CD14++/CD16+ intermediate monocyte CD62L expression was identified post-vaccine (p=0.0122), compared to placebo, with no difference in soluble plasma CD62L between groups (p=0.875). CD11b median fluorescence intensity was increased in CD3+/CD4+ T-lymphocytes in nitrate-treated volunteers (p=0.0095).

Conclusions

Dietary nitrate reduced BP, as previously shown, indicating efficacy of the intervention. Importantly, we also now show for the first time that inorganic nitrate suppresses the systemic inflammatory response, specifically by reducing the numbers and activation state of CD14++/CD16+ intermediate monocytes. Furthermore, an increased expression of CD3+/CD4+ T-cell CD11b and preserved FMD in healthy volunteers treated with nitrate, suggests an anti-inflammatory phenotype, induced by the intervention, leading to improved endothelial function. Inorganic dietary nitrate modulates endothelial function through the attenuation of inflammatory responses and may be of potential therapeutic benefit in patients with established CAD.

Funding Acknowledgement

Type of funding sources: None.

Religious Fasting of Muslim Patients After Metabolic and Bariatric Surgery: a Modified Delphi Consensus

BACKGROUND

Fasting during Ramadan is one of the five pillars of the Muslim faith. Despite the positive effects of fasting on health, there are no guidelines or clear recommendations regarding fasting after metabolic/bariatric surgery (MBS). The current study reports the result of a modified Delphi consensus among expert metabolic/bariatric surgeons with experience in managing patients who fast after MBS.

METHODS

A committee of 61 well-known metabolic and bariatric surgeons from 24 countries was created to participate in the Delphi consensus. The committee voted on 45 statements regarding recommendations and controversies around fasting after MBS. An agreement/disagreement ≥ of 70.0% was regarded as consensus.

RESULTS

The experts reached a consensus on 40 out of 45 statements after two rounds of voting. One hundred percent of the experts believed that fasting needs special nutritional support in patients who underwent MBS. The decision regarding fasting must be coordinated among the surgeon, the nutritionist and the patient. At any time after MBS, 96.7% advised stopping fasting in the presence of persistent symptoms of intolerance. Seventy percent of the experts recommended delaying fasting after MBS for 6 to 12 months after combined and malabsorptive procedures according to the patient's situation and surgeon's experience, and 90.1% felt that proton pump inhibitors should be continued in patients who start fasting less than 6 months after MBS. There was consensus that fasting may help in weight loss, improvement/remission of non-alcoholic fatty liver disease, dyslipidemia, hypertension and type 2 diabetes mellitus among 88.5%, 90.2%, 88.5%, 85.2% and 85.2% of experts, respectively.

CONCLUSION

Experts voted and reached a consensus on 40 statements covering various aspects of fasting after MBS.

30-Day Morbidity and Mortality of Bariatric Surgery During the COVID-19 Pandemic: a Multinational Cohort Study of 7704 Patients from 42 Countries

BACKGROUND

There are data on the safety of cancer surgery and the efficacy of preventive strategies on the prevention of postoperative symptomatic COVID-19 in these patients. But there is little such data for any elective surgery. The main objectives of this study were to examine the safety of bariatric surgery (BS) during the coronavirus disease 2019 (COVID-19) pandemic and to determine the efficacy of perioperative COVID-19 protective strategies on postoperative symptomatic COVID-19 rates.

METHODS

We conducted an international cohort study to determine all-cause and COVID-19-specific 30-day morbidity and mortality of BS performed between 01/05/2020 and 31/10/2020.

RESULTS

Four hundred ninety-nine surgeons from 185 centres in 42 countries provided data on 7704 patients. Elective primary BS (n = 7084) was associated with a 30-day morbidity of 6.76% (n = 479) and a 30-day mortality of 0.14% (n = 10). Emergency BS, revisional BS, insulin-treated type 2 diabetes, and untreated obstructive sleep apnoea were associated with increased complications on multivariable analysis. Forty-three patients developed symptomatic COVID-19 postoperatively, with a higher risk in non-whites. Preoperative self-isolation, preoperative testing for SARS-CoV-2, and surgery in institutions not concurrently treating COVID-19 patients did not reduce the incidence of postoperative COVID-19. Postoperative symptomatic COVID-19 was more likely if the surgery was performed during a COVID-19 peak in that country.

CONCLUSIONS

BS can be performed safely during the COVID-19 pandemic with appropriate perioperative protocols. There was no relationship between preoperative testing for COVID-19 and self-isolation with symptomatic postoperative COVID-19. The risk of postoperative COVID-19 risk was greater in non-whites or if BS was performed during a local peak.

Long-term effects of bariatric surgery on cardiovascular risk factors in Singapore

INTRODUCTION

Bariatric surgery is considered an effective treatment for weight loss and for improving the metabolic profile of patients with obesity. Obesity-related comorbidities such as hyperlipidaemia and type 2 diabetes mellitus (DM) are significant cardiovascular risk factors. Additionally, prospective clinical trials have shown that statins increase the risk of development of DM, and many patients with obesity are on statins. We retrospectively examined the effect of bariatric surgery on lipid profile, DM control and weight loss at the five-year follow-up.

METHODS

In total, 104 patients undergoing bariatric surgery from 2008 to 2012 were retrospectively studied. 36 patients were on preoperative statins. Their lipid profile, DM control and weight loss were examined at the one-year and five-year follow-ups.

RESULTS

Both high-density lipoprotein and triglyceride levels showed significant improvement at the one-year and five-year follow-ups (p = 0.01). Total cholesterol showed significant improvement at the one-year follow-up (-0.30 mmol/dL, p = 0.0338); however, better control was not sustained at the five-year follow-up (-0.15 mmol/dL, p = 0.133). Low-density lipoprotein did not show any considerable improvement at the one- and five-year follow-ups (-0.27 mmol/dL, p = 0.150 and -0.24 mmol/dL, p = 0.138, respectively). A statistically significant improvement in DM control was observed in these patients and in those on preoperative statins. Weight loss was sustained at one and five years.

CONCLUSION

Bariatric surgery does not confer a uniform improvement in lipid profile in the long term. It does, however, induce efficient weight loss and improvement in diabetic profile, even in patients on preoperative statins.

30-Day Morbidity and Mortality of Bariatric Surgery During the COVID-19 Pandemic: a Multinational Cohort Study of 7704 Patients from 42 Countries

BACKGROUND

There are data on the safety of cancer surgery and the efficacy of preventive strategies on the prevention of postoperative symptomatic COVID-19 in these patients. But there is little such data for any elective surgery. The main objectives of this study were to examine the safety of bariatric surgery (BS) during the coronavirus disease 2019 (COVID-19) pandemic and to determine the efficacy of perioperative COVID-19 protective strategies on postoperative symptomatic COVID-19 rates.

METHODS

We conducted an international cohort study to determine all-cause and COVID-19-specific 30-day morbidity and mortality of BS performed between 01/05/2020 and 31/10/2020.

RESULTS

Four hundred ninety-nine surgeons from 185 centres in 42 countries provided data on 7704 patients. Elective primary BS (n = 7084) was associated with a 30-day morbidity of 6.76% (n = 479) and a 30-day mortality of 0.14% (n = 10). Emergency BS, revisional BS, insulin-treated type 2 diabetes, and untreated obstructive sleep apnoea were associated with increased complications on multivariable analysis. Forty-three patients developed symptomatic COVID-19 postoperatively, with a higher risk in non-whites. Preoperative self-isolation, preoperative testing for SARS-CoV-2, and surgery in institutions not concurrently treating COVID-19 patients did not reduce the incidence of postoperative COVID-19. Postoperative symptomatic COVID-19 was more likely if the surgery was performed during a COVID-19 peak in that country.

CONCLUSIONS

BS can be performed safely during the COVID-19 pandemic with appropriate perioperative protocols. There was no relationship between preoperative testing for COVID-19 and self-isolation with symptomatic postoperative COVID-19. The risk of postoperative COVID-19 risk was greater in non-whites or if BS was performed during a local peak.

Outcomes of oesophageal cancer treated with neoadjuvant compared with definitive chemoradiotherapy

Introduction: We report outcomes of patients with oesophageal cancer treated with neoadjuvant chemoradiotherapy (NACRT) plus surgery or definitive chemoradiotherapy (chemoRT) at our institution. Methods: We retrospectively reviewed patients who underwent chemoRT from 2005 to 2017. The primary outcome was overall survival (OS). Secondary outcomes were disease-free survival (DFS) and toxicities. Results: We identified 96 patients with median age of 64 years and squamous cell carcinoma in 82.3%. Twenty-nine patients (30.2%) received NACRT plus surgery, 67 patients (69.8%) received definitive chemoRT. Median follow-up was 13.5 months. The 3/5-year OS were 26.4%/13.4%, and 59.6%/51.6% in the definitive chemoRT and NACRT plus surgery groups, respectively. The 3/5-year DFS were 19.3%/12.3%, and 55.7%/37.2% in the definitive chemoRT and NACRT plus surgery groups, respectively. NACRT plus surgery significantly improved OS (hazard ratio [HR] 0.40, 95% confidence interval [CI] 0.22–0.72, P<0.01) and DFS (subhazard ratio [SHR] 5.21, 95 CI 1.20–22.7, P=0.03). Multivariable analysis for OS in the definitive chemoRT group indicated stage (1–2 vs 3–4a; HR 2.17, 95% CI 1.15–4.11, P=0.02) and feeding tube (no tube versus tube; HR 1.85, 95% CI 1.00–3.43, P=0.05) as significantly associated with OS. The cumulative incidence of local recurrence was significantly higher in the definitive chemoRT group (SHR 5.21, 95 CI 1.2022.7, P=0.03). Nineteen patients (65.5%) had postoperative complications. Conclusion: NACRT plus surgery improved OS and DFS. However, in view of treatment-related complications, careful selection of patients is warranted. With the predominant histology of our cohort being squamous cell carcinoma (SCC), our results may be more re levant for those with SCC. Keywords: Neoadjuvant chemoradiotherapy, oesophageal cancer, surgery

Hedgehog transcriptional effector GLI mediates mTOR-Induced PD-L1 expression in gastric cancer organoids

Tumors evade immune surveillance by expressing Programmed Death-Ligand 1 (PD-L1), subsequently inhibiting CD8⁺ cytotoxic T lymphocyte function. Response of gastric cancer to immunotherapy is relatively low. Our laboratory has reported that Helicobacter pylori-induced PD-L1 expression within the gastric epithelium is mediated by the Hedgehog (Hh) signaling pathway. The PI3K/AKT/mTOR pathway is activated in gastric cancer and may have immunomodulatory potential. We hypothesize that Hh signaling mediates mTOR-induced PD-L1 expression. Patient-derived organoids (PDOs) were generated from gastric biopsies and resected tumor tissues. Autologous organoid/immune cell co-cultures were used to study the immunosuppressive function of MDSCs. NanoString Digital Spatial Profiling (DSP) of immune-related protein markers using FFPE slide-mounted tissues from gastric cancer patients was performed. DSP analysis showed infiltration of immunosuppressive MDSCs expressing Arg1, CD66b, VISTA and IDO1 within cancer tissues. Orthotopic transplantation of patient derived organoids (PDOs) resulted in the engraftment of organoids and the development of histology similar to that observed in the patient's tumor tissue. PDO/immune cell co-cultures revealed that PD-L1-expressing organoids were unresponsive to nivolumab in vitro in the presence of PMN-MDSCs. Depletion of PMN-MDSCs within these co-cultures sensitized the organoids to anti-PD-1/PD-L1-induced cancer cell death. Rapamycin decreased phosphorylated S6K, Gli2 and PD-L1 expression in PDO/immune cell co-cultures. Transcriptional regulation of PD-L1 by GLI1 and GLI2 was blocked by rapamycin. In conclusion, the PDO/immune cell co-cultures may be used to study immunosuppressive MDSC function within the gastric tumor microenvironment. The mTOR signaling pathway mediates GLI-induced PD-L1 expression in gastric cancer.

Mortality from esophagectomy for esophageal cancer across low, middle, and high-income countries: An international cohort study

BACKGROUND

No evidence currently exists characterising global outcomes following major cancer surgery, including esophageal cancer. Therefore, this study aimed to characterise impact of high income countries (HIC) versus low and middle income countries (LMIC) on the outcomes following esophagectomy for esophageal cancer.

METHOD

This international multi-center prospective study across 137 hospitals in 41 countries included patients who underwent an esophagectomy for esophageal cancer, with 90-day follow-up. The main explanatory variable was country income, defined according to the World Bank Data classification. The primary outcome was 90-day postoperative mortality, and secondary outcomes were composite leaks (anastomotic leak or conduit necrosis) and major complications (Clavien-Dindo Grade III - V). Multivariable generalized estimating equation models were used to produce adjusted odds ratios (ORs) and 95% confidence intervals (CI95%).

RESULTS

Between April 2018 to December 2018, 2247 patients were included. Patients from HIC were more significantly older, with higher ASA grade, and more advanced tumors. Patients from LMIC had almost three-fold increase in 90-day mortality, compared to HIC (9.4% vs 3.7%, p < 0.001). On adjusted analysis, LMIC were independently associated with higher 90-day mortality (OR: 2.31, CI95%: 1.17-4.55, p = 0.015). However, LMIC were not independently associated with higher rates of anastomotic leaks (OR: 1.06, CI95%: 0.57-1.99, p = 0.9) or major complications (OR: 0.85, CI95%: 0.54-1.32, p = 0.5), compared to HIC.

CONCLUSION

Resections in LMIC were independently associated with higher 90-day postoperative mortality, likely reflecting a failure to rescue of these patients following esophagectomy, despite similar composite anastomotic leaks and major complication rates to HIC. These findings warrant further research, to identify potential issues and solutions to improve global outcomes following esophagectomy for cancer.

Association of metabolic-bariatric surgery with long-term survival in adults with and without diabetes: a one-stage meta-analysis of matched cohort and prospective controlled studies with 174 772 participants

BACKGROUND

Metabolic-bariatric surgery delivers substantial weight loss and can induce remission or improvement of obesity-related risks and complications. However, more robust estimates of its effect on long-term mortality and life expectancy-especially stratified by pre-existing diabetes status-are needed to guide policy and facilitate patient counselling. We compared long-term survival outcomes of severely obese patients who received metabolic-bariatric surgery versus usual care.

METHODS

We did a prespecified one-stage meta-analysis using patient-level survival data reconstructed from prospective controlled trials and high-quality matched cohort studies. We searched PubMed, Scopus, and MEDLINE (via Ovid) for randomised trials, prospective controlled studies, and matched cohort studies comparing all-cause mortality after metabolic-bariatric surgery versus non-surgical management of obesity published between inception and Feb 3, 2021. We also searched grey literature by reviewing bibliographies of included studies as well as review articles. Shared-frailty (ie, random-effects) and stratified Cox models were fitted to compare all-cause mortality of adults with obesity who underwent metabolic-bariatric surgery compared with matched controls who received usual care, taking into account clustering of participants at the study level. We also computed numbers needed to treat, and extrapolated life expectancy using Gompertz proportional-hazards modelling. The study protocol is prospectively registered on PROSPERO, number CRD42020218472.

FINDINGS

Among 1470 articles identified, 16 matched cohort studies and one prospective controlled trial were included in the analysis. 7712 deaths occurred during 1·2 million patient-years. In the overall population consisting 174 772 participants, metabolic-bariatric surgery was associated with a reduction in hazard rate of death of 49·2% (95% CI 46·3-51·9, p<0·0001) and median life expectancy was 6·1 years (95% CI 5·2-6·9) longer than usual care. In subgroup analyses, both individuals with (hazard ratio 0·409, 95% CI 0·370-0·453, p<0·0001) or without (0·704, 0·588-0·843, p<0·0001) baseline diabetes who underwent metabolic-bariatric surgery had lower rates of all-cause mortality, but the treatment effect was considerably greater for those with diabetes (between-subgroup I² 95·7%, p<0·0001). Median life expectancy was 9·3 years (95% CI 7·1-11·8) longer for patients with diabetes in the surgery group than the non-surgical group, whereas the life expectancy gain was 5·1 years (2·0-9·3) for patients without diabetes. The numbers needed to treat to prevent one additional death over a 10-year time frame were 8·4 (95% CI 7·8-9·1) for adults with diabetes and 29·8 (21·2-56·8) for those without diabetes. Treatment effects did not appear to differ between gastric bypass, banding, and sleeve gastrectomy (I² 3·4%, p=0·36). By leveraging the results of this meta-analysis and other published data, we estimated that every 1·0% increase in metabolic-bariatric surgery utilisation rates among the global pool of metabolic-bariatric candidates with and without diabetes could yield 5·1 million and 6·6 million potential life-years, respectively.

INTERPRETATION

Among adults with obesity, metabolic-bariatric surgery is associated with substantially lower all-cause mortality rates and longer life expectancy than usual obesity management. Survival benefits are much more pronounced for people with pre-existing diabetes than those without.

FUNDING

None.