Alterations in plasma protein N-glycosylation after caloric restriction and bariatric surgery

BACKGROUND

Protein glycosylation is an enzymatic process known to reflect an individual's physiologic state and changes thereof. The impact of metabolic interventions on plasma protein N-glycosylation has only been sparsely investigated.

OBJECTIVE

To examine alterations in plasma protein N-glycosylation following changes in caloric intake and bariatric surgery.

SETTING

University of Texas Southwestern Medical Center, US and Oxford University Hospitals, UK.

METHODS

This study included 2 independent patient cohorts that recruited 10 and 37 individuals with obesity undergoing a period of caloric restriction followed by bariatric surgery. In both cohorts, clinical data were collated, and the composition of plasma protein N-glycome was analyzed chromatographically. Linear mixed models adjusting for age, sex, and multiple testing (false discovery rate <.05) were used to investigate longitudinal changes in glycosylation features and metabolic clinical markers.

RESULTS

A low-calorie diet resulted in a decrease in high-branched trigalactosylated and trisialylated plasma N-glycans and a concomitant increase in low-branched N-glycans in both cohorts. Participants from one cohort additionally underwent a washout period during which caloric intake and body weight increased, resulting in reversal of the initial low-calorie diet-related changes in the plasma N-glycome. Immediate postoperative follow-up revealed the same pattern of N-glycosylation changes in both cohorts-an increase in complex, high-branched, antennary fucosylated, extensively galactosylated and sialylated N-glycans and a substantial decline in simpler, low-branched, core fucosylated, bisected, agalactosylated, and asialylated glycans. A 12-month postoperative monitoring in one cohort showed that N-glycan complexity declines while low branching increases.

CONCLUSIONS

Plasma protein N-glycosylation undergoes extensive alterations following caloric restriction and bariatric surgery. These comprehensive changes may reflect the varying inflammatory status of the individual following dietary and surgical interventions and subsequent weight loss.

How-I-do-it: laparoscopic intragastric submucosal dissection (LISD) for gastric and gastro-oesophageal junction early lesions

PURPOSE

Laparoscopic intragastric submucosal dissection (LISD) is a novel approach to the resection of gastric lesion that are not amenable to conventional endoscopic approaches. The technique permits favourable access to lesions situated at the cardia and angular notch of the stomach, enables en-bloc resection of large areas of tissue, and can prevent the need of formal gastrectomy or oesophagectomy in selected patients.

METHODS

All cases were deemed suitable for LISD by a multidisciplinary team panel following endoscopic assessment (using white light enhancement, chromoendoscopy and magnification endoscopy) that was integrated when needed with EUS, CT scan or PET scan. The surgical technique consisted in a 3-port laparoscopic approach; after establishment of pneumoperitoneum, three gastrotomies were performed to enable port insertion into the stomach. Following establishment of stable pneumogastrium, the area of interest was identified, submucosal hyaluronic acid injection performed to provide a cushion in the plane of dissection, and the excision area was circumferentially marked with cautery. Resection was completed using cautery hook, along a plane parallel to the muscolaris propria. After the specimen was extracted in a retrieval bag, intracorporeal single layer running suture closure of gastrotomies was performed. The abdominal wall closed by layers and tap block performed along with local anaesthetic injection on skin incision. Measures were taken to ensure correct orientation of resected specimens prior to fixation.

RESULTS

During the study period that spans from 2014 and 2022, a total of 11 patients underwent LISD for limited lesions of the stomach, 10 were located at gastro-oesophageal junction and one at the angular incisura. Four patients were female, seven males. The median age was 74 (46-79) years. R0 resection rate was 54.5%. Mean operative time was 109 min with very low blood loss (10 ml). Mortality rate was 0%, no immediate major complications (Grade II-V Clavien Dindo), including haemorrhage or perforation, occurred in these cases. Two patients developed dysphagia later that was successfully treated with endoscopic balloon dilatations. Median hospital stay was 3 days and median oral intake was on day 1 post-procedural.

CONCLUSIONS

Laparoscopic intragastric submucosal dissection is shown to be a safe and effective intervention for the treatment of early gastric cancers in selected patients having undergone deemed not amenable for endoscopic submucosal resection for their technically challenging location. Its application can serve as route to avoid formal surgery and the associated morbidity.

Association of Upper GI Surgery of Great Britain and Ireland (AUGIS) Delphi consensus recommendations on the adoption of robotic upper GI surgery

BACKGROUND

The adoption of robotic platforms in upper gastrointestinal (GI) surgery is expanding rapidly. The absence of centralised guidance and governance in adoption of new surgical technologies may lead to an increased risk of patient harm.

METHODS

Surgeon stakeholders participated in a Delphi consensus process following a national open-invitation in-person meeting on the adoption of robotic upper GI surgery. Consensus agreement was deemed met if >80% agreement was achieved.

RESULTS

Following two rounds of Delphi voting, 25 statements were agreed on covering the training process, governance and good practice for surgeons' adoption in upper GI surgery. One statement failed to achieve consensus.

CONCLUSIONS

These recommendations are intended to support surgeons, patients and health systems in the adoption of robotics in upper GI surgery.

The effect of bariatric surgery type on cardiac reverse remodelling

INTRODUCTION

Bariatric surgery is effective in reversing adverse cardiac remodelling in obesity. However, it is unclear whether the three commonly performed operations; Roux-en-Y Gastric Bypass (RYGB), Laparoscopic Sleeve Gastrectomy (LSG) and Laparoscopic Adjustable Gastric Band (LAGB) are equal in their ability to reverse remodelling.

METHODS

Fifty-eight patients underwent CMR to assess left ventricular mass (LVM), LV mass:volume ratio (LVMVR) and LV eccentricity index (LVei) before and after bariatric surgery (26 RYGB, 22 LSG and 10 LAGB), including 46 with short-term (median 251-273 days) and 43 with longer-term (median 983-1027 days) follow-up. Abdominal visceral adipose tissue (VAT) and epicardial adipose tissue (EAT) were also assessed.

RESULTS

All three procedures resulted in significant decreases in excess body weight (48-70%). Percentage change in VAT and EAT was significantly greater following RYGB and LSG compared to LAGB at both timepoints (VAT:RYGB -47% and -57%, LSG -47% and -54%, LAGB -31% and -25%; EAT:RYGB -13% and -14%, LSG -16% and -19%, LAGB -5% and -5%). Patients undergoing LAGB, whilst having reduced LVM (-1% and -4%), had a smaller decrease at both short (RYGB: -8%, p < 0.005; LSG: -11%, p < 0.0001) and long (RYGB: -12%, p = 0.009; LSG: -13%, p < 0.0001) term timepoints. There was a significant decrease in LVMVR at the long-term timepoint following both RYGB (-7%, p = 0.006) and LSG (-7%, p = 0.021), but not LAGB (-2%, p = 0.912). LVei appeared to decrease at the long-term timepoint in those undergoing RYGB (-3%, p = 0.063) and LSG (-4%, p = 0.015), but not in those undergoing LAGB (1%, p = 0.857). In all patients, the change in LVM correlated with change in VAT (r = 0.338, p = 0.0134), while the change in LVei correlated with change in EAT (r = 0.437, p = 0.001).

CONCLUSIONS

RYGB and LSG appear to result in greater decreases in visceral adiposity, and greater reverse LV remodelling with larger reductions in LVM, concentric remodelling and pericardial restraint than LAGB.

Delayed Surgical Intervention After Chemoradiotherapy in Esophageal Cancer: (DICE) Study

OBJECTIVE

To determine the impact of delayed surgical intervention following chemoradiotherapy (CRT) on survival from esophageal cancer.

BACKGROUND

CRT is a core component of multimodality treatment for locally advanced esophageal cancer. The timing of surgery following CRT may influence the probability of performing an oncological resection and the associated operative morbidity.

METHODS

This was an international, multicenter, cohort study, including patients from 17 centers who received CRT followed by surgery between 2010 and 2020. In the main analysis, patients were divided into 4 groups based upon the interval between CRT and surgery (0-50, 51-100, 101-200, and >200 days) to assess the impact upon 90-day mortality and 5-year overall survival. Multivariable logistic and Cox regression provided hazard ratios (HRs) with 95% CIs adjusted for relevant patient, oncological, and pathologic confounding factors.

RESULTS

A total of 2867 patients who underwent esophagectomy after CRT were included. After adjustment for relevant confounders, prolonged interval following CRT was associated with an increased 90-day mortality compared with 0 to 50 days (reference): 51 to 100 days (HR=1.54, 95% CI: 1.04-2.29), 101 to 200 days (HR=2.14, 95% CI: 1.37-3.35), and >200 days (HR=3.06, 95% CI: 1.64-5.69). Similarly, a poorer 5-year overall survival was also observed with prolonged interval following CRT compared with 0 to 50 days (reference): 101 to 200 days (HR=1.41, 95% CI: 1.17-1.70), and >200 days (HR=1.64, 95% CI: 1.24-2.17).

CONCLUSIONS

Prolonged interval following CRT before esophagectomy is associated with increased 90-day mortality and poorer long-term survival. Further investigation is needed to understand the mechanism that underpins these adverse outcomes observed with a prolonged interval to surgery.

Practice variation in anastomotic leak after esophagectomy: Unravelling differences in failure to rescue

INTRODUCTION

Failure to rescue (FTR) is an important outcome measure after esophagectomy and reflects mortality after postoperative complications. Differences in FTR have been associated with hospital resection volume. However, insight into how centers manage complications and achieve their outcomes is lacking. Anastomotic leak (AL) is a main contributor to FTR. This study aimed to assess differences in FTR after AL between centers, and to identify factors that explain these differences.

METHODS

TENTACLE - Esophagus is a multicenter, retrospective cohort study, which included 1509 patients with AL after esophagectomy. Differences in FTR were assessed between low-volume (<20 resections), middle-volume (20-60 resections) and high-volume centers (≥60 resections). Mediation analysis was performed using logistic regression, including possible mediators for FTR: case-mix, hospital resources, leak severity and treatment.

RESULTS

FTR after AL was 11.7%. After adjustment for confounders, FTR was lower in high-volume vs. low-volume (OR 0.44, 95%CI 0.2-0.8), but not versus middle-volume centers (OR 0.67, 95%CI 0.5-1.0). After mediation analysis, differences in FTR were found to be explained by lower leak severity, lower secondary ICU readmission rate and higher availability of therapeutic modalities in high-volume centers. No statistically significant direct effect of hospital volume was found: high-volume vs. low-volume 0.86 (95%CI 0.4-1.7), high-volume vs. middle-volume OR 0.86 (95%CI 0.5-1.4).

CONCLUSION

Lower FTR in high-volume compared with low-volume centers was explained by lower leak severity, less secondary ICU readmissions and higher availability of therapeutic modalities. To reduce FTR after AL, future studies should investigate effective strategies to reduce leak severity and prevent secondary ICU readmission.

Changes in epicardial and visceral adipose tissue depots following bariatric surgery and their effect on cardiac geometry

Introduction

Obesity affects cardiac geometry, causing both eccentric (due to increased cardiac output) and concentric (due to insulin resistance) remodelling. Following bariatric surgery, reversal of both processes should occur. Furthermore, epicardial adipose tissue loss following bariatric surgery may reduce pericardial restraint, allowing further chamber expansion. We investigated these changes in a serial imaging study of adipose depots and cardiac geometry following bariatric surgery.

Methods

62 patients underwent cardiac magnetic resonance (CMR) before and after bariatric surgery, including 36 with short-term (median 212 days), 37 medium-term (median 428 days) and 32 long-term (median 1030 days) follow-up. CMR was used to assess cardiac geometry (left atrial volume (LAV) and left ventricular end-diastolic volume (LVEDV)), LV mass (LVM) and LV eccentricity index (LVei - a marker of pericardial restraint). Abdominal visceral (VAT) and epicardial (EAT) adipose tissue were also measured.

Results

Patients on average had lost 21kg (38.9% excess weight loss, EWL) at 212 days and 36kg (64.7% EWL) at 1030 days following bariatric surgery. Most VAT and EAT loss (43% and 14%, p<0.0001) occurred within the first 212 days, with non-significant reductions thereafter. In the short-term LVM (7.4%), LVEDV (8.6%) and LAV (13%) all decreased (all p<0.0001), with change in cardiac output correlated with LVEDV (r=0.35,p=0.03) and LAV change (r=0.37,p=0.03). Whereas LVM continued to decrease with time (12% decrease relative to baseline at 1030 days, p<0.0001), both LAV and LVEDV had returned to baseline by 1030 days. LV mass:volume ratio (a marker of concentric hypertrophy) reached its nadir at the longest timepoint (p<0.001). At baseline, LVei correlated with baseline EAT (r=0.37,p=0.0040), and decreased significantly from 1.09 at baseline to a low of 1.04 at 428 days (p<0.0001). Furthermore, change in EAT following bariatric surgery correlated with change in LVei (r=0.43,p=0.0007).

Conclusions

Cardiac volumes show a biphasic response to weight loss, initially becoming smaller and then returning to pre-operative sizes by 1030 days. We propose this is due to an initial reversal of eccentric remodelling followed by reversal of concentric remodelling. Furthermore, we provide evidence for a role of EAT contributing to pericardial restraint, with EAT loss improving markers of pericardial restraint.

OGC O01 Delayed surgical Intervention after Chemoradiotherapy in Esophageal cancer (DICE) study

Background

Chemoradiotherapy (CRT) is a core component of curative treatment for esophageal cancer for locally advanced esophageal cancer. Salvage esophagectomy is undertaken in patients who experience recurrent or residual cancer post-CRT. This study aims determine the impact of delayed surgical intervention following chemoradiotherapy on survival from oesophageal cancer.

Methods

This was an international, multi-center, retrospective cohort study involving seventeen tertiary international centers, including patients who received CRT followed by surgery between 2010–2020. In the main analysis patients were divided into four groups based upon the interval between chemoradiotherapy and surgery (0–50, 51–100, 101–200 and &gt;200 days) to assess the impact upon 90-day mortality and 5-year overall survival (OS). Multivariable logistic and Cox regression provided hazard rations (HRs) with 95% confidence intervals (95%CI) adjusted for relevant patient, oncological and pathological confounding factors.

Results

2,867 patients who underwent oesophagectomy after CRT were included. The mean age of the cohort was 63.2 (9.47) years. 79.7% were male; and 87.2% had an ASA grade ≥2. After adjustment for relevant confounders, prolonged interval following CRT was associated with an increased 90-day mortality; compared to 0–50 (reference), 51–100 days (HR=1.54, 95%CI 1.04–2.29), 101–200 days (HR=2.14, 95%CI 1.37–3.35) and &gt;200 days (HR=3.06, 95%CI 1.64–5.69). Similarly, a poorer 5-year survival was also observed with prolonged interval following CRT compared to 0–50 (reference), 101–200 days (HR=1.41, 95%CI 1.17–1.70) and &gt;200 days (HR=1.64, 95%CI 1.24–2.17).

Conclusions

Prolonged interval following CRT and esophagectomy is associated with increased 90-day mortality and poorer long-term survival. Patients must be carefully considered and counselled regarding surveillance and salvage esophagectomy following CRT.

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.

Severity of oEsophageal Anastomotic Leak in patients after oesophagectomy: the SEAL score

Background

Anastomotic leak (AL) is a common but severe complication after oesophagectomy. It is unknown how to determine the severity of AL objectively at diagnosis. Determining leak severity may guide treatment decisions and improve future research. This study aimed to identify leak-related prognostic factors for mortality, and to develop a Severity of oEsophageal Anastomotic Leak (SEAL) score.

Methods

This international, retrospective cohort study in 71 centres worldwide included patients with AL after oesophagectomy between 2011 and 2019. The primary endpoint was 90-day mortality. Leak-related prognostic factors were identified after adjusting for confounders and were included in multivariable logistic regression to develop the SEAL score. Four classes of leak severity (mild, moderate, severe, and critical) were defined based on the risk of 90-day mortality, and the score was validated internally.

Results

Some 1509 patients with AL were included and the 90-day mortality rate was 11.7 per cent. Twelve leak-related prognostic factors were included in the SEAL score. The score showed good calibration and discrimination (c-index 0.77, 95 per cent c.i. 0.73 to 0.81). Higher classes of leak severity graded by the SEAL score were associated with a significant increase in duration of ICU stay, healing time, Comprehensive Complication Index score, and Esophagectomy Complications Consensus Group classification.

Conclusion

The SEAL score grades leak severity into four classes by combining 12 leak-related predictors and can be used to the assess severity of AL after oesophagectomy.

P-OGC41 Survival after curative chemoradiotherapy or neoadjuvant therapy and surgery converges in higher-risk patients with oesophageal cancer

Background

Both curative chemoradiotherapy (cCRT) and neoadjuvant chemoradiotherapy and surgery (nCRTS) can be considered as treatments for potentially curable oesophageal squamous cell carcinoma (OSCC). Whilst this equipoise does not exist in oesophageal adenocarcinoma (OAC), there are patients in whom treatment decisions are not straightforward, creating an overlapping group in which cCRT might be considered in preference to neoadjuvant chemotherapy or chemoradiotherapy and surgery (nC(R)TS). We aim to see how survival changes between unmatched and matched cohorts of patients with OAC and OSCC treated with cCRT or nC(R)TS, to reflect difficult multidisciplinary team treatment decisions.

Methods

Patients treated with nC(R)TS or cCRT for OSCC and OAC were identified on an intention-to-treat basis from April 2016 to April 2019, allowing a minimum 2-year follow up from diagnosis. Upper third tumours were excluded due to clear preference for cCRT. Preoperative variables were compared using descriptive statistics, with OSCC and OAC analysed separately. Significantly different variables were used to generate propensity scores. Cohorts were then matched and analysis repeated to assess cohort symmetry. Overall survival and 2-year survival were investigated using Kaplan-Meier survival curves and log-rank testing. Analysis was performed in R.

Results

60 and 231 patients with OSCC and OAC were treated with cCRT or nC(R)TS. In the unmatched analysis, nC(R)TS had superior overall and 2-year survival, however there were significant differences in age, Charlson comorbidity index and cancer stage in OSCC and OAC cohorts, and in tumour site for the OAC cohort. After propensity score matching, differences in overall and 2-year survival reduced, though no results reached significance (OSCC: nCRTS 2y survival 58% vs 51% and 54% in unmatched and matched cCRT cohorts, respectively; OAC: cCRT 2y survival 51% vs 60% and 56% in unmatched and matched nC(R)TS cohorts, respectively).

Conclusions

These data suggest that as patient and cancer related factors increase the difficulty of treatment decisions, the survival benefit of surgery reduces in both OSCC and OAC. These results underline the need for randomised controlled trials using current treatment and staging strategies, as there have been considerable advances since original comparisons of neoadjuvant and curative chemoradiotherapy. This study is limited by relatively short follow up and unpowered sample sizes, however the coded nature of the analysis provides a structure for regular review of outcomes in our unit using routinely collected data, and could be easily applied more widely.

P-OGC40 Enhanced recovery after oesophagectomy at Oxford University Hospitals: the benefit of having a discharge target

Background

Enhanced recovery after surgery (ERAS) is a multimodal approach to decreasing morbidity and accelerating return-of-function after major surgery. However, the majority of patients undergoing oesophagectomy for cancer experience some kind of complication, which extends their admission and causes pathway deviation. Thus, the value of having a discharge target (Day 8 at our institution) could be challenged. In this study we reviewed our experience using this pathway, with a focus on: (i) whether length of stay and morbidity has improved since pathway implementation (ii) describing the medical and non-medical reasons for extended admission (iii) identifying pre-operative predictors of pathway deviation.

Methods

A retrospective review of a prospectively maintained database was performed. Complications are recorded during routine clinical care using standardised definitions set out by the Esophageal Complications Consensus group,  and are updated in the database at a weekly departmental meeting. Median and interquartile range were used for descriptors and differences tested with Mann-Whitney U test or Chi squared tests, using SPSS ver 26. Multivariable models were fitted to establish independent predictors of pathway deviation, using a binary logistic regression approach with bootstrapping.

Results

150 of 448 patients met the 8-day target. Patients treated since 2018 were significantly more likely meet their discharge date (OR 1.28, P = 0.041) compared to 2015-2017, and have less complications. Surgical quality was unchanged. Thirty-day mortality increased but was still low (0.9% vs 1.8%, P = 0.067).  Aside from having a complication (OR 4.15,  P &lt; 0.001), independent predictor of delayed discharge was female sex (OR 2.6, P = 0.003), squamous cell cancer histology (OR 2.8, P = 0.014) and low socio-economic status (OR 1.33, P = 0.014), but not age, smoking, BMI, co-morbidities and other baseline variables.

Conclusions

Enhanced recovery after oesophagectomy provides clear goals for the patient and multi-disciplinary team, however the target is often not met owing to the frequent nature of post-operative complications. Nonetheless these targets provide a culture for accelerated recovery, with steady improvement in short-term outcomes over time.  A number of specific patient-groups are more likely to have extended admissions independent of complications, which has implications for optimising prehabilitation services. Overall , these findings suggest that having a discharge target is valuable,  even though it often is not met.

P-OGC42 Hiatus Hernia following Minimally Invasive Oesophagectomy - a Single Centre Experience

Background

Hiatus hernia is an established complication following oesophagectomy, with a higher incidence when a minimally invasive approach (MIO) is undertaken. Literature reports the incidence post-MIO to be vary between 4.5% -26%. There is no clear consensus on the optimum operative management of this complication. The aim of this study was to establish the incidence of hiatus hernia post MIO (HiHO) at a single hospital site, identify predisposing factors, and evaluate subsequent surgical management of this complication.

Methods

Single-center data were retrospectively analysed of MIOs conducted consecutively between May 2018 and October 2020. A minimum follow-up period of 6 months was required for inclusion. HiHO was defined by radiological confirmation. Data collected included patient demographics, comorbidities, risk factors for hiatus hernia and patient’s post-operative course. Statistical analyses were performed using Fischer’s exact or independent t-test as appropriate.

Results

50 patients who underwent MIO were included; mean follow up of 1.92 years. 7 (14%) presented with HiHO. There was no significant difference in age or gender between patients with and without HiHO. HiHO patients had a significantly lower BMI (95% CI 1.083-8.271; P = 0.012) and were more likely to have underlying lung conditions (P = 0.029). A higher incidence of pre-existing hiatus hernia was present among the HiHO group (43% vs 21%). Of those developing HiHO, 6 (86%) were symptomatic requiring surgical reduction with crural repair of hiatus or colopexy; 2 had a recurrence of HiHO requiring subsequent colopexy.

Conclusions

This study represents the largest single centre analysis of hiatus hernia post minimally invasive oesophagectomy. Our results correlate with the literature, that there is a significant risk of hiatus hernia following minimally invasive oesophagectomy. This risk is increased among patients with pre-operative hiatus hernia, low BMI, and pre-existing lung conditions. Crural repair or colopexy are options for surgical management of HiHO. Colopexy may potentially prevent recurrence of HiHO. A larger study size and a consensus from experts in the field would be beneficial in guiding operative management of HiHO to improve patient outcomes.

P-OGC53 Dashboarding for real-time analysis of oesophagogastric outcomes data

Background

The typical paradigm for surgical service evaluation is intermittent audit based on perceived clinical need and mandated requirements. A better model would be monitoring patient outcomes automatically in real-time, with up-to-date cumulative frequencies of key surgical performance indicators such as surgical quality and morbidity, as changes in performance could be detected and reacted to at an earlier stage. This study aimed to develop a dashboarding technology to support real-time visualisation of prospectively maintained oesophagogastric cancer surgery data.

Methods

CODA is a bespoke databank (implemented in MS SQL Server, with HTML, C# and JavaScript) for oesophagogastric cancer care at our centre. We built on a custom dashboard interface for displaying this information in real-time, using Shiny for R and Tableau. We identified the key performance indicators (KPIs) to monitor in the dashboard, and defined benchmarks based on accepted standards, or our prevailing performance (based on 448 consecutive patients who underwent oesophagectomy between 2015 – 2020). The domains selected were surgical quality, length of stay, early mortality, and priority complications. Complications were defined according to the Esophagectomy Complications Consensus Group.

Results

For surgical quality, our benchmarks based on prevailing performance were (i) &gt;90% &gt;15 lymph node yield (ii) &lt;2-5% longitudinal R1 (iii) &lt;20-30% CRM R1. For length of stay, our benchmarks were (i) &gt;33% meeting 8 day discharge target (ii) &lt;15% missing target discharge without a medical complication (iii) &lt;20% staying longer than two weeks. For 30 & 90 day mortality, our benchmarks were 2% and 4% respectively. For complications, two sets were identified: (i) common complications (occurring at &gt; 2 / year, monitored 2-yearly) (ii) impactful complications (&gt;1 / year, &gt;1 week median additional stay, monitored 5-yearly)

Conclusions

The CODA dashboard provides real-time appraisal of oesophagogastric cancer surgery practice, highlighting changes in performance and providing opportunity for early intervention. The platform can be used for personal, departmental or inter-institutional service evaluation. The KPIs will be extended to oesophagogastric cancer survival as the test set matures. The interface and wider benefits of CODA implementation are presented, together with the dissemination plan for use in other oesophagogastric centres.

Near infra-red fluorescence identification of the thoracic duct to prevent chyle leaks during oesophagectomy

Background

Chyle leaks following oesophagectomy are a frustrating complication of surgery with considerable morbidity. The use of near infra-red (NIR) fluorescence in surgery is an emerging technology and the use of fluorescence to identify the thoracic duct has been demonstrated in animal work and early human case reports. This study evaluated the use mesenteric and enteral administration of indocyanine green (ICG) in humans to identify the thoracic duct during oesophagectomy.

Methods

Patients undergoing oesophagectomy were recruited to the study. Administration of ICG via an enteral route or mesenteric injection was evaluated. Fluorescence was assessed using a NIR fluorescence enabled laparoscope system with a visual scoring system and signal to background ratios. Visualisation of the thoracic duct under white light and NIR fluorescence was compared as well as any identification of active chyle leak. Patients were followed up post-operatively for adverse events and chyle leak.

Results

20 patients received ICG and were included in the study. The enteral route failed to fluoresce the thoracic duct. Mesenteric injection (17 patients) identified the thoracic duct under fluorescence prior to white light in 70% of patients with a mean signal to background ratio of 5.35. In 6 participants, a possible active chyle leak was identified under fluorescence with 4 showing active chyle leak from what was identified as the thoracic duct.

Conclusion

This study demonstrates that ICG administration via mesenteric injection can highlight the thoracic duct during oesophagectomy and may be a potential technology to reduce chyle leak following surgery.

Clinical trial registration

Clinical trials.gov (NCT03292757).

Current Status of Endoscopic Vacuum Therapy in the Management of Esophageal Perforations and Post-Operative Leaks

Esophageal wall defects, including perforations and postoperative leaks, are associated with high morbidity and mortality and pose a significant management challenge. In light of the high morbidity of surgical management or revision, in recent years, endoscopic vacuum therapy (EVT) has emerged as a novel alternative treatment strategy. EVT involves transoral endoscopic placement of a polyurethane sponge connected to an externalized nasogastric tube to provide continuous negative pressure with the intention of promoting defect healing, facilitating cavity drainage, and ameliorating sepsis. In the last decade, EVT has become increasingly adopted in the management of a diverse spectrum of esophageal defects. Its popularity has been attributed in part to the growing body of evidence suggesting superior outcomes and defect closure rates in excess of 80%. This growing body of evidence, coupled with the ongoing evolution of the technology and techniques of deployment, suggests that the utilization of EVT has become increasingly widespread. Here, we aimed to review the current status of the field, addressing the mechanism of action, indications, technique methodology, efficacy, safety, and practical considerations of EVT implementation. We also sought to highlight future directions for the use of EVT in esophageal wall defects.

Technique of open and minimally invasive intrathoracic reconstruction following esophagectomy-an expert consensus based on a modified Delphi process

BACKGROUND

In recent years, minimally invasive Ivor Lewis (IL) esophagectomy with high intrathoracic anastomosis has emerged as surgical standard of care for esophageal cancer in expert centers. Alongside this process, many divergent technical aspects of this procedure have been devised in different centers. This study aims at achieving international consensus on the surgical steps of IL reconstruction using Delphi methodology.

METHODS

The expert panel consisted of specialized esophageal surgeons from 8 European countries. During a two-round Delphi process, a detailed analysis and consensus on key steps of intrathoracic gastric tube reconstruction (IL esophagectomy) was performed.

RESULTS

Response rates in Delphi rounds 1 and 2 were 100% (22 of 22 experts) and 83.3% (20 of 24 experts), respectively. Three essential technical areas of intrathoracic gastric tube reconstruction were identified: first, vascularization of the gastric conduit, second, gastric mobilization, tube formation and pull-up, and third, anastomotic technique. In addition, 3 main techniques for minimally invasive intrathoracic anastomosis are currently practiced: (i) end-to-side circular stapled, (ii) end-to-side double stapling, and (iii) side-to-side linear stapled technique. The step-by-step procedural analysis unveiled common approaches but also different expert practice.

CONCLUSION

This precise technical description may serve as a clinical guideline for intrathoracic reconstruction after esophagectomy. In addition, the results may aid to harmonize the technical evolution of this complex surgical procedure and thereby facilitate surgical training.

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.

SP5.1.5 Bariatric surgery is associated with greater survival and metabolic health benefits than conventional medical management in people with NAFLD

Aims

Non-alcoholic fatty liver disease (NAFLD) represents the hepatic manifestation of the metabolic syndrome.There are no licensed pharmacotherapies for NAFLD, and it is rapidly becoming the leading cause of liver failure worldwide.Bariatric surgery (BS) is an effective and durable intervention for weight loss and type 2 diabetes (T2D) but is not recommended in the UK’s NICE guidelines for NAFLD management.We aimed to determine whether BS was associated with NAFLD regression.

Methods

1067 people with NAFLD were included in this observational cohort study.Liver histology/validated non-invasive biomarkers were used to diagnose NAFLD.Markers of liver and metabolic health were recorded longitudinally for participants undergoing hepatology-led (n = 702) or BS (n = 365) management in a UK tertiary centre. 1-year outcomes were compared using mixed models. 5-year mortality was compared using Cox proportional-hazards regression.

Results

T2D prevalence was similar between cohorts (p = 0.06). Differences in other baseline factors were observed (age, gender, and body mass index (BMI), all p &lt; 0001). BS showed a significantly lower adjusted 5-year mortality (p = 0.02). Both interventions were associated with improved biomarkers of liver health e.g. ALT (p = 0.00). Greater improvements in targets of NAFLD management such as HbA1c (p = 0.00) and BMI (p = 0.00) were observed after BS.

Conclusions

BS showed an improved 5-year survival compared to hepatology-led management. This may be explained by greater improvements in key targets for NAFLD regression in the BS cohort. However, residual confounding despite adjusted survival analysis cannot be excluded. A prospective randomised trial is recommended to ensure fair comparison of these interventions and enhance the clinical management of NAFLD.

Laparoscopic vs. open feeding jejunostomy insertion in oesophagogastric cancer

Background

Jejunal feeding is an invaluable method by which to improve the nutritional status of patients undergoing neoadjuvant and surgical treatment of oesophageal malignancies. However, the insertion of a feeding jejunostomy can cause significant postoperative morbidity. The aim of this study is to compare the outcomes of patients undergoing placement of feeding jejunostomy by conventional laparotomy with an alternative laparoscopic approach.

Methods

A retrospective review of data prospectively collected at the Oxford Oesophagogastric Centre between August 2017 and July 2019 was performed including consecutive patients undergoing feeding jejunostomy insertion.

Results

In the study period, 157 patients underwent jejunostomy insertion in the context of oesophageal cancer therapy, 126 (80%) by open technique and 31 (20%) laparoscopic. Pre-operative demographic and nutritional characteristics were broadly similar between groups. In the early postoperative period jejunostomy-associated complications were noted in 54 cases (34.4%) and were significantly more common among those undergoing open as compared with laparoscopic insertion (38.1% vs. 19.3%, P = 0.049). Furthermore, major complications were more common among those undergoing open insertion, whether as a stand-alone or at the time of staging laparoscopy (n = 11/71), as compared with insertion at the time of oesophagectomy (n = 3/86, P = 0.011).

Conclusions

This report represents the largest to our knowledge single-centre comparison of open vs. laparoscopic jejunostomy insertion in patients undergoing oesophagectomy in the treatment of gastroesophageal malignancy. We conclude that the laparoscopic jejunostomy insertion technique described represents a safe and effective approach to enteral access which may offer superior outcomes to conventional open procedures.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12893-021-01318-9.

Extensive weight loss reduces glycan age by altering IgG N-glycosylation

BACKGROUND

Obesity, a major global health problem, is associated with increased cardiometabolic morbidity and mortality. Protein glycosylation is a frequent posttranslational modification, highly responsive to inflammation and ageing. The prospect of biological age reduction, by changing glycosylation patterns through metabolic intervention, opens many possibilities. We have investigated whether weight loss interventions affect inflammation- and ageing-associated IgG glycosylation changes, in a longitudinal cohort of bariatric surgery patients. To support potential findings, BMI-related glycosylation changes were monitored in a longitudinal twins cohort.

METHODS

IgG N-glycans were chromatographically profiled in 37 obese patients, subjected to low-calorie diet, followed by bariatric surgery, across multiple timepoints. Similarly, plasma-derived IgG N-glycan traits were longitudinally monitored in 1680 participants from the TwinsUK cohort.

RESULTS

Low-calorie diet induced a marked decrease in the levels of IgG N-glycans with bisecting GlcNAc, whose higher levels are usually associated with ageing and inflammatory conditions. Bariatric surgery resulted in extensive alterations of the IgG N-glycome that accompanied progressive weight loss during 1-year follow-up. We observed a significant increase in digalactosylated and sialylated glycans, and a substantial decrease in agalactosylated and core fucosylated IgG N-glycans (adjusted p value range 7.38 × 10-04-3.94 × 10-02). This IgG N-glycan profile is known to be associated with a younger biological age and reflects an enhanced anti-inflammatory IgG potential. Loss of BMI over a 20 year period in the TwinsUK cohort validated a weight loss-associated agalactosylation decrease (adjusted p value 1.79 × 10-02) and an increase in digalactosylation (adjusted p value 5.85 × 10-06).

CONCLUSIONS

Altogether, these findings highlight that weight loss substantially affects IgG N-glycosylation, resulting in reduced glycan and biological age.

Fit-for-Discharge Criteria after Esophagectomy: An International Expert Delphi Consensus

There are no internationally recognized criteria available to determine preparedness for hospital discharge after esophagectomy. This study aims to achieve international consensus using Delphi methodology. The expert panel consisted of 40 esophageal surgeons spanning 16 countries and 4 continents. During a 3-round, web-based Delphi process, experts voted for discharge criteria using 5-point Likert scales. Data were analyzed using descriptive statistics. Consensus was reached if agreement was ≥75% in round 3. Consensus was achieved for the following basic criteria: nutritional requirements are met by oral intake of at least liquids with optional supplementary nutrition via jejunal feeding tube. The patient should have passed flatus and does not require oxygen during mobilization or at rest. Central venous catheters should be removed. Adequate analgesia at rest and during mobilization is achieved using both oral opioid and non-opioid analgesics. All vital signs should be normal unless abnormal preoperatively. Inflammatory parameters should be trending down and close to normal (leucocyte count ≤12G/l and C-reactive protein ≤80 mg/dl). This multinational Delphi survey represents the first expert-led process for consensus criteria to determine 'fit-for-discharge' status after esophagectomy. Results of this Delphi survey may be applied to clinical outcomes research as an objective measure of short-term recovery. Furthermore, standardized endpoints identified through this process may be used in clinical practice to guide decisions regarding patient discharge and may help to reduce the risk of premature discharge or prolonged admission.

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.

Comparison of short-term outcomes from the International Oesophago-Gastric Anastomosis Audit (OGAA), the Esophagectomy Complications Consensus Group (ECCG), and the Dutch Upper Gastrointestinal Cancer Audit (DUCA)

BACKGROUND

The Esophagectomy Complications Consensus Group (ECCG) and the Dutch Upper Gastrointestinal Cancer Audit (DUCA) have set standards in reporting outcomes after oesophagectomy. Reporting outcomes from selected high-volume centres or centralized national cancer programmes may not, however, be reflective of the true global prevalence of complications. This study aimed to compare complication rates after oesophagectomy from these existing sources with those of an unselected international cohort from the Oesophago-Gastric Anastomosis Audit (OGAA).

METHODS

The OGAA was a prospective multicentre cohort study coordinated by the West Midlands Research Collaborative, and included patients undergoing oesophagectomy for oesophageal cancer between April and December 2018, with 90 days of follow-up.

RESULTS

The OGAA study included 2247 oesophagectomies across 137 hospitals in 41 countries. Comparisons with the ECCG and DUCA found differences in baseline demographics between the three cohorts, including age, ASA grade, and rates of chronic pulmonary disease. The OGAA had the lowest rates of neoadjuvant treatment (OGAA 75.1 per cent, ECCG 78.9 per cent, DUCA 93.5 per cent; P < 0.001). DUCA exhibited the highest rates of minimally invasive surgery (OGAA 57.2 per cent, ECCG 47.9 per cent, DUCA 85.8 per cent; P < 0.001). Overall complication rates were similar in the three cohorts (OGAA 63.6 per cent, ECCG 59.0 per cent, DUCA 62.2 per cent), with no statistically significant difference in Clavien-Dindo grades (P = 0.752). However, a significant difference in 30-day mortality was observed, with DUCA reporting the lowest rate (OGAA 3.2 per cent, ECCG 2.4 per cent, DUCA 1.7 per cent; P = 0.013).

CONCLUSION

Despite differences in rates of co-morbidities, oncological treatment strategies, and access to minimal-access surgery, overall complication rates were similar in the three cohorts.

Bariatric surgery for patients with type 2 diabetes mellitus requiring insulin: Clinical outcome and cost-effectiveness analyses

BACKGROUND

Although bariatric surgery is well established as an effective treatment for patients with obesity and type 2 diabetes mellitus (T2DM), there exists reluctance to increase its availability for patients with severe T2DM. The aims of this study were to examine the impact of bariatric surgery on T2DM resolution in patients with obesity and T2DM requiring insulin (T2DM-Ins) using data from a national database and to develop a health economic model to evaluate the cost-effectiveness of surgery in this cohort when compared to best medical treatment (BMT).

METHODS AND FINDINGS

Clinical data from the National Bariatric Surgical Registry (NBSR), a comprehensive database of bariatric surgery in the United Kingdom, were extracted to analyse outcomes of patients with obesity and T2DM-Ins who underwent primary bariatric surgery between 2009 and 2017. Outcomes for this group were combined with data sourced from a comprehensive literature review in order to develop a state-transition microsimulation model to evaluate cost-effectiveness of bariatric surgery versus BMT for patients over a 5-year time horizon. The main outcome measure for the clinical study was insulin cessation at 1-year post-surgery: relative risks (RR) summarising predictive factors were determined, unadjusted, and after adjusting for variables including age, initial body mass index (BMI), duration of T2DM, and weight loss. Main outcome measures for the economic evaluation were total costs, total quality-adjusted life years (QALYs), and incremental cost-effectiveness ratio (ICER) at willingness-to-pay threshold of GBP£20,000. A total of 2,484 patients were eligible for inclusion, of which 1,847 had 1-year follow-up data (mean age of 51 years, mean initial BMI 47.2 kg/m2, and 64% female). 67% of patients no longer required insulin at 1-year postoperatively: these rates persisted for 4 years. Roux-en-Y gastric bypass (RYGB) was associated with a higher rate of insulin cessation (71.7%) than sleeve gastrectomy (SG; 64.5%; RR 0.92, confidence interval (CI) 0.86-0.99) and adjustable gastric band (AGB; 33.6%; RR 0.45, CI 0.34-0.60; p < 0.001). When adjusted for percentage total weight loss and demographic variables, insulin cessation following surgery was comparable for RYGB and SG (RR 0.97, CI 0.90-1.04), with AGB having the lowest cessation rates (RR 0.55, CI 0.40-0.74; p < 0.001). Over 5 years, bariatric surgery was cost saving compared to BMT (total cost GBP£22,057 versus GBP£26,286 respectively, incremental difference GBP£4,229). This was due to lower treatment costs as well as reduced diabetes-related complications costs and increased health benefits. Limitations of this study include loss to follow-up of patients within the NBSR dataset and that the time horizon for the economic analysis is limited to 5 years. In addition, the study reflects current medical and surgical treatment regimens for this cohort of patients, which may change.

CONCLUSIONS

In this study, we observed that in patients with obesity and T2DM-Ins, bariatric surgery was associated with high rates of postoperative cessation of insulin therapy, which is, in turn, a major driver of overall reductions in direct healthcare cost. Our findings suggest that a strategy utilising bariatric surgery for patients with obesity and T2DM-Ins is cost saving to the national healthcare provider (National Health Service (NHS)) over a 5-year time horizon.

Gastrointestinal side effects of upper gastrointestinal cancer surgery

In this chapter, we describe the gastrointestinal side effects of oesophagectomy, gastrectomy and pancreaticoduodenectomy for cancer, with a focus on long-term functional impairments and their management. Improvements in upper gastrointestinal cancer surgery have led to a growing group of long-term survivors. The invasive nature of these surgeries profoundly alters the upper gastrointestinal anatomy, with lasting implications for long-term function, and how these impairments may be treated. Successfully maintaining a high quality of survivorship requires multidisciplinary approach, with survivorship care plans focused on function as much as the detection of recurrence.

Impact on postoperative complications of changes in skeletal muscle mass during neoadjuvant chemotherapy for gastro-oesophageal cancer

BACKGROUND

Risk assessment is relevant to predict postoperative outcomes in patients with gastro-oesophageal cancer. This cohort study aimed to assess body composition changes during neoadjuvant chemotherapy and investigate their association with postoperative complications.

METHODS

Consecutive patients with gastro-oesophageal cancer undergoing neoadjuvant chemotherapy and surgery with curative intent between 2016 and 2019 were identified from a specific database and included in the study. CT images before and after neoadjuvant chemotherapy were used to assess the skeletal muscle index, sarcopenia, and subcutaneous and visceral fat index.

RESULTS

In a cohort of 199 patients, the mean skeletal muscle index decreased during neoadjuvant therapy (from 51·187 to 49·19 cm² /m² ; P < 0·001) and the rate of sarcopenia increased (from 42·2 to 54·3 per cent; P < 0·001). A skeletal muscle index decrease greater than 5 per cent was not associated with an increased risk of total postoperative complications (odds ratio 0·91, 95 per cent c.i. 0·52 to 1·59; P = 0·736) or severe complications (odds ratio 0·66, 0·29 to 1·53; P = 0·329).

CONCLUSION

Skeletal muscle index decreased during neoadjuvant therapy but was not associated with postoperative complications.

Variation in esophageal anastomosis technique-the role of collaborative learning

Centralization of care has improved outcomes in esophagogastric (EG) cancer surgery. However, specialist surgical centers often work within clinical silos, with little transfer of knowledge and experience. Although variation exists in multiple dimensions of perioperative care, the differences in operative technique are rarely studied. An esophageal anastomosis workshop was held to identify areas of common and differing practice within the operative technique. Surgeons showed videos of their anastomosis technique by open and minimally invasive surgery. Each video was followed by a discussion. Surgeons from 10 different EG cancer centers attended. Eight key technical differences and learning points were identified and discussed: the optimum diameter of the gastric conduit; avoiding ischemia in the gastric conduit; minimizing esophageal trauma; the use of an esophageal mucosal collar; omental wrapping; intraoperative leak testing; ideal diameter of the circular stapler and the growing use of linear stapled anastomoses. The workshop received positive feedback from participants and on 2 years follow-up, 40% stated that they believed that the learning of tips and techniques during the workshop has contributed to lowering their anastomotic leak rate. Many differences exist in surgical technique. The reasons for, and crucially the significance of, these differences must be discussed and examined. Workshops provide a forum for peer-to-peer collaborative learning to reflect on one's own practice and improve surgical technique. These changes can, in turn, generate incremental improvements in patient care and postoperative outcomes.

Diagnostic criteria and symptom grading for delayed gastric conduit emptying after esophagectomy for cancer: international expert consensus based on a modified Delphi process

Delayed gastric conduit emptying (DGCE) after esophagectomy for cancer is associated with adverse outcomes and troubling symptoms. Widely accepted diagnostic criteria and a symptom grading tool for DGCE are missing. This hampers the interpretation and comparison of studies. A modified Delphi process, using repeated web-based questionnaires, combined with live interim group discussions was conducted by 33 experts within the field, from Europe, North America, and Asia. DGCE was divided into early DGCE if present within 14 days of surgery and late if present later than 14 days after surgery. The final criteria for early DGCE, accepted by 25 of 27 (93%) experts, were as follows: >500 mL diurnal nasogastric tube output measured on the morning of postoperative day 5 or later or >100% increased gastric tube width on frontal chest x-ray projection together with the presence of an air-fluid level. The final criteria for late DGCE accepted by 89% of the experts were as follows: the patient should have 'quite a bit' or 'very much' of at least two of the following symptoms; early satiety/fullness, vomiting, nausea, regurgitation or inability to meet caloric need by oral intake and delayed contrast passage on upper gastrointestinal water-soluble contrast radiogram or on timed barium swallow. A symptom grading tool for late DGCE was constructed grading each symptom as: 'not at all', 'a little', 'quite a bit', or 'very much', generating 0, 1, 2, or 3 points, respectively. For the five symptoms retained in the diagnostic criteria for late DGCE, the minimum score would be 0, and the maximum score would be 15. The final symptom grading tool for late DGCE was accepted by 27 of 31 (87%) experts. For the first time, diagnostic criteria for early and late DGCE and a symptom grading tool for late DGCE are available, based on an international expert consensus process.

AKR1D1 is a novel regulator of metabolic phenotype in human hepatocytes and is dysregulated in non-alcoholic fatty liver disease

OBJECTIVE

Non-alcoholic fatty liver disease (NAFLD) is the hepatic manifestation of metabolic syndrome. Steroid hormones and bile acids are potent regulators of hepatic carbohydrate and lipid metabolism. Steroid 5β-reductase (AKR1D1) is highly expressed in human liver where it inactivates steroid hormones and catalyzes a fundamental step in bile acid synthesis.

METHODS

Human liver biopsies were obtained from 34 obese patients and AKR1D1 mRNA expression levels were measured using qPCR. Genetic manipulation of AKR1D1 was performed in human HepG2 and Huh7 liver cell lines. Metabolic assessments were made using transcriptome analysis, western blotting, mass spectrometry, clinical biochemistry, and enzyme immunoassays.

RESULTS

In human liver biopsies, AKR1D1 expression decreased with advancing steatosis, fibrosis and inflammation. Expression was decreased in patients with type 2 diabetes. In human liver cell lines, AKR1D1 knockdown decreased primary bile acid biosynthesis and steroid hormone clearance. RNA-sequencing identified disruption of key metabolic pathways, including insulin action and fatty acid metabolism. AKR1D1 knockdown increased hepatocyte triglyceride accumulation, insulin sensitivity, and glycogen synthesis, through increased de novo lipogenesis and decreased β-oxidation, fueling hepatocyte inflammation. Pharmacological manipulation of bile acid receptor activation prevented the induction of lipogenic and carbohydrate genes, suggesting that the observed metabolic phenotype is driven through bile acid rather than steroid hormone availability.

CONCLUSIONS

Genetic manipulation of AKR1D1 regulates the metabolic phenotype of human hepatoma cell lines, driving steatosis and inflammation. Taken together, the observation that AKR1D1 mRNA is down-regulated with advancing NAFLD suggests that it may have a crucial role in the pathogenesis and progression of the disease.

Obesity surgery and Ehlers-Danlos syndrome: challenges and considerations based on a case report

Ehlers-Danlos syndrome is a hereditary connective tissue disorder that has gastrointestinal manifestations in over 50% of its cases. We present the first case of bariatric surgery in a patient with Ehlers-Danlos syndrome and outline management challenges in the context of the relevant literature. A 56-year-old man with type IV Ehlers-Danlos syndrome and a body mass index of 41.8 kg/m² was referred to the bariatric centre of the Churchill Hospital, Oxford, for consideration of surgery for morbid obesity. His comorbidity included type 2 diabetes, hypertension, dyslipidaemia and obstructive sleep apnoea. He underwent a laparoscopic Roux-en-Y gastric bypass. His initial recovery was uneventful and he was discharged on the first postoperative day. Six weeks later, he presented with 43.9% excess weight loss and improved glycaemic control. Three months postoperatively, however, he complained of dysphagia, regurgitation and postprandial pain. A barium meal and gastroscopy suggested the presence of a gastric diverticulum. A surgical exploration was planned. Intraoperative gastroscopy demonstrated an asymmetrical gastric pouch dilatation and the pouch was therefore refashioned laparoscopically. Despite the initial symptomatic relief, two months later he experienced retrosternal pain with progressive dysphagia. Since then, multiple endoscopic dilatations of the gastro-oesophageal junction have been performed for recurrence of symptoms. Finally, a laparoscopic hiatus hernia repair and adhesiolysis was performed resulting in complete relief of patient's symptoms. Bariatric management of patients with Ehlers-Danlos syndrome can prove challenging. The bariatric team must implement a careful management plan including a detailed consent process, a tailored surgical intervention and a follow-up focused on potential gastrointestinal manifestations.

Distribution of lymph node metastases in esophageal carcinoma [TIGER study]: study protocol of a multinational observational study

BACKGROUND

An important parameter for survival in patients with esophageal carcinoma is lymph node status. The distribution of lymph node metastases depends on tumor characteristics such as tumor location, histology, invasion depth, and on neoadjuvant treatment. The exact distribution is unknown. Neoadjuvant treatment and surgical strategy depends on the distribution pattern of nodal metastases but consensus on the extent of lymphadenectomy has not been reached. The aim of this study is to determine the distribution of lymph node metastases in patients with resectable esophageal or gastro-esophageal junction carcinoma in whom a transthoracic esophagectomy with a 2- or 3-field lymphadenectomy is performed. This can be the foundation for a uniform worldwide staging system and establishment of the optimal surgical strategy for esophageal cancer patients.

METHODS

The TIGER study is an international observational cohort study with 50 participating centers. Patients with a resectable esophageal or gastro-esophageal junction carcinoma in whom a transthoracic esophagectomy with a 2- or 3-field lymphadenectomy is performed in participating centers will be included. All lymph node stations will be excised and separately individually analyzed by pathological examination. The aim is to include 5000 patients. The primary endpoint is the distribution of lymph node metastases in esophageal and esophago-gastric junction carcinoma specimens following transthoracic esophagectomy with at least 2-field lymphadenectomy in relation to tumor histology, tumor location, invasion depth, number of lymph nodes and lymph node metastases, pre-operative diagnostics, neo-adjuvant therapy and (disease free) survival.

DISCUSSION

The TIGER study will provide a roadmap of the location of lymph node metastases in relation to tumor histology, tumor location, invasion depth, number of lymph nodes and lymph node metastases, pre-operative diagnostics, neo-adjuvant therapy and survival. Patient-tailored treatment can be developed based on these results, such as the optimal radiation field and extent of lymphadenectomy based on the primary tumor characteristics.

TRIAL REGISTRATION

NCT03222895 , date of registration: July 19th, 2017.

PYY plays a key role in the resolution of diabetes following bariatric surgery in humans

BACKGROUND

Bariatric surgery leads to early and long-lasting remission of type 2 diabetes (T2D). However, the mechanisms behind this phenomenon remain unclear. Among several factors, gut hormones are thought to be crucial mediators of this effect. Unlike GLP-1, the role of the hormone peptide tyrosine tyrosine (PYY) in bariatric surgery in humans has been limited to appetite regulation and its impact on pancreatic islet secretory function and glucose metabolism remains under-studied.

METHODS

Changes in PYY concentrations were examined in obese patients after bariatric surgery and compared to healthy controls. Human pancreatic islet function was tested upon treatment with sera from patients before and after the surgery, in presence or absence of PYY. Alterations in intra-islet PYY release and insulin secretion were analysed after stimulation with short chain fatty acids (SCFAs), bile acids and the cytokine IL-22.

FINDINGS

We demonstrate that PYY is a key effector of the early recovery of impaired glucose-mediated insulin and glucagon secretion in bariatric surgery. We establish that the short chain fatty acid propionate and bile acids, which are elevated after surgery, can trigger PYY release not only from enteroendocrine cells but also from human pancreatic islets. In addition, we identify IL-22 as a new factor which is modulated by bariatric surgery in humans and which directly regulates PYY expression and release.

INTERPRETATION

This study shows that some major metabolic benefits of bariatric surgery can be emulated ex vivo. Our findings are expected to have a direct impact on the development of new non-surgical therapy for T2D correction.

Oligometastatic recurrence of an oesophageal adenocarcinoma at a chest drain site following radical treatment: palliative treatment or resection?

A 62-year-old female patient diagnosed with oesophageal adenocarcinoma underwent radical treatment consisting of neoadjuvant chemotherapy and oesophagectomy with no major complications. Eleven months later, she re-presented with a mass at one of the chest drain sites. A PET-CT scan and biopsy demonstrated this to be a single recurrence of the oesophageal adenocarcinoma. Excision of the metastatic lesion was considered as per metachronous single site metastasis. However, the operation was postponed due to acute kidney injury. Restaging after 6 weeks revealed progressive metastatic disease. The patient underwent palliative therapy and passed away soon after. Oesophageal cancer recurrence has a very poor prognosis, and factors such as the disease-free interval, site of recurrence and tumour pathological factors must be considered when stratifying for suitability for metastasectomy. A period of watchful waiting followed by restaging is essential to rule out patients with indolent metastatic disease.

Non-radical, stepwise complete endoscopic resection of Barrett's epithelium in short segment Barrett's esophagus has a low stricture rate

Background and aims: Radical endoscopic excision of Barrett's epithelium performing 4 - 6 endoscopic resections during the same endoscopic session results in complete Barrett's eradication but has a high stricture rate (40 - 80 %). Therefore radiofrequency ablation is preferred after endoscopic mucosal resection (EMR) of visible nodules. We investigated the clinical outcome of non-radical, stepwise endoscopic mucosal resection with a maximum of two endoscopic resections per endoscopic session. Methods: We analysed our prospectively maintained database of patients undergoing esophageal EMR for early neoplasia in Barrett's esophagus from 2009 to 2014. EMR was performed using a maximum of two band ligation mucosectomies per endoscopic session; thereafter, follow-up was 3-monthly and EMR was repeated as required for Barrett's eradication. Results: In total, 118 patients underwent staging EMR for early Barrett's neoplasia. Subsequently, 27 patients underwent surgery/chemotherapy due to deep submucosal or more advanced tumor stages or were managed conservatively. The remaining 91 patients with high grade dysplasia (48), intramucosal (38) or submucosal cancer (5) in the resected nodule underwent further endoscopic therapy with a mean follow-up of 24 months. Remission of dysplasia/neoplasia was achieved in 95.6 % after 12 months treatment. Stepwise endoscopic Barrett's resection resulted in complete Barrett's eradication in 36/91 patients (39.6 %) in a mean of four sessions; 40/91 patients (44.0 %) had a short circumferential Barrett's segment (< 3 cm). In this group, repeated EMR achieved complete Barrett's excision in 85.0 %. One patient developed a stricture (1.1 %), one a delayed bleeding, and there were no perforations. Conclusion: In patients with a short Barrett's segment, non-radical endoscopic Barrett's resection at the time of scheduled endoscopy follow-up allows complete Barrett's eradication with very low stricture rate.

Attempted validation of the NUn score and inflammatory markers as predictors of esophageal anastomotic leak and major complications

The ability to predict complications following esophagectomy/extended total gastrectomy would be of great clinical value. A recent study demonstrated significant correlations between anastomotic leak (AL) and numerical values of C-reactive protein (CRP), white cell count (WCC) and albumin measured on postoperative day (POD) 4. A predictive model comprising all three (NUn score >10) was found to be highly sensitive and discriminant in predicting AL and complications. We attempted a retrospective validation in our center. Data were collected on all resections performed during a 5-year period (April 2008-2013) using prospectively maintained databases. Our biochemistry laboratory uses a maximum CRP value (156 mg/L), unlike that of the original study; otherwise all variables and outcome measures were comparable. Analysis was performed for all patients with complete blood results on POD4. Three hundred twenty-six patients underwent resection, of which 248 had POD4 bloods. There were 21 AL overall (6.44%); 16 among those with complete POD4 blood results (6.45%). There were 8 (2.45%) in-hospital deaths; 7 (2.82%) in those with POD4 results. No parameters were associated with AL or complication severity on univariate analysis. WCC was associated with AL in multivariate binary logistic regression with albumin and CRP (OR 1.23 [95% CI 1.03-1.47]; P = 0.021). When a binary variable of CRP ≥ 156 mg/L was used rather than an absolute value, no factors were significant. Mean NUn was 8.30 for AL, compared with 8.40 for non-AL (P = 0.710 independent t-test). NUn > 10 predicted 0 of 16 leaks (sensitivity 0.00%, specificity 94.4%, receiver operator curve [ROC] area under the curve [AUC] 0.485; P = 0.843). NUn > 7.65 was 93% sensitive and 21.6% specific. ROC for WCC alone was comparable with NUn (AUC 0.641 [0.504-0.779]; P = 0.059; WCC > 6.89 93.8% sensitive, 20.7% specific; WCC > 15 6.3% sensitive and 97% specific). There were no associations between any parameters and other complications. In a comparable cohort with the original study, we demonstrated a similar multivariate association between WCC alone on POD4 and subsequent demonstration of AL, but not albumin or CRP (measured up to 156 mg/L). The NUn score overall (calculated with this caveat) and a threshold of 10 was not found to have clinical utility in predicting AL or complications.

Is conservative management for gastric perforation secondary to intragastric balloon possible? Case report and review of literature

Intragastric balloon (IGB) is one of the available options for the management of morbid obesity. The procedure is generally safe and of moderate efficacy in most of the cases. One of the reported complications of IGB is gastric perforation. The management of this complication is classically surgical. To our knowledge, conservative management for gastric perforation secondary to IGB has not been reported. A 27-year-old female patient presented with sudden abdominal pain in the left upper quadrant, 2 months after having an IGB placed. The provisional diagnosis was gastric perforation. Balloon extraction was performed and a conservative management of the gastric perforation was pursued successfully. We therefore propose that this sort of management might be adopted in carefully selected cases.

Laparoscopic management of a delayed traumatic diaphragmatic rupture complicated by bowel strangulation

Traumatic rupture of the diaphragm (TDR) presents diagnostic difficulty, with basic radiological investigations discovering less than half of all cases. As a consequence, complications of diaphragmatic rupture may present long after the initial injury has occurred—the time delay obscuring diagnosis. Once discovered repair is necessary with previous reports advocating open repair. Here, we report a case of traumatic diaphragmatic rupture causing small bowel obstruction 20 years after initial injury. The patient, a young woman, underwent successful laparoscopic assisted diaphragmatic repair with small bowel resection. TDR is an unusual but important differential diagnosis of an acute abdomen. A high index of suspicion is required to avoid delayed diagnosis and increased mortality.

The effect of formalizing enhanced recovery after esophagectomy with a protocol

Enhanced recovery after surgery (ERAS) pathways aim to accelerate functional return and discharge from hospital. They have proven effective in many forms of surgery, most notably colorectal. However, experience in esophagectomy has been limited. A recent study reported significant reductions in pulmonary complications, mortality, and length of stay following the introduction of an ERAS protocol alone, without the introduction of any clinical changes. We instituted a similar change 16 months ago, introducing a protocol to provide a formal framework, for our existing postoperative care. This retrospective analysis compared outcome following esophagectomy for the 16 months before and 20 months after this change. Data were collected from prospectively maintained secure web-based multidisciplinary databases. Complication severity was classified using the Clavien-Dindo scale. Operative mortality was defined as death within 30 days of surgery, or at any point during the same hospital admission. Lower respiratory tract infection was defined as clinical evidence of infection, with or without radiological signs. Respiratory complications included lower respiratory tract infection, pleural effusion (irrespective of drainage), pulmonary collapse, and pneumothorax. Statistical analysis was performed using SPSS v21. One hundred thirty-two patients underwent esophagectomy (55 protocol group; 77 before). All were performed open. There were no differences between the two groups in terms of age, gender, operation, use of neoadjuvant therapy, cell type, stage, tumor site, or American Society of Anesthesiologists grade. Median length of stay was 14.0 days (protocol) compared with 12.0 before (interquartile range 9-19 and 9.5-15.5, respectively; P = 0.073, Mann-Whitney U-test). Readmission within 30 days of discharge occurred in five (9.26%) and six (8.19%; P = 1.000, Fisher's exact test). There were four in-hospital deaths (3.03%): one (1.82%) and three (3.90%), respectively (P = 0.641). There were no differences in the severity of complications (P = non-significant; Pearson's chi-squared). There were no differences in the type of complications occurring in either group. The protocol was completed successfully by 26 (47.3%). No baseline factors were predictive of this. In contrast to previous studies, we did not demonstrate any improvement in outcome by formalizing our existing pathway using a written protocol. Consequently, improvements in short-term outcome from esophagectomy within ERAS would seem to be primarily due to improvements in components of perioperative care. Consequently, we would recommend that centers introducing new (or reviewing existing) ERAS pathways for esophagectomy focus on optimizing clinical aspects of such standardized pathways.

Gender influence on long-term weight loss after three bariatric procedures: gastric banding is less effective in males in a retrospective analysis

BACKGROUND

Identifying factors that influence weight loss after bariatric surgery is one way to predict a successful surgical outcome. Knowledge of the effect of gender on weight loss after bariatric surgery has not been well demonstrated in the literature despite being noted in every day practice. The aim of this study was to find the influence of gender on long-term weight loss after bariatric surgery.

METHODS

A retrospective analysis of data retrieved from a prospectively maintained bariatric database was conducted.

RESULTS

The study included 640 consecutive patients. Their mean age was 38 ± 10 years, mean preoperative body mass index was 44.9 ± 8.4 kg/m2, and mean preoperative excess weight (EW %) was 108.3 ± 38.4%. The mean of the average excess weight loss (EWL %) was 43.3 ± 42.4%. Three procedures were utilized: Roux-en-Y gastric bypass (RYGB), vertical banded gastroplasty (VBG), and gastric banding (GB). Both VBG and RYGB induced significantly more EWL % than GB (d = 22.1%, p < 0.001 and d = 16, p = 0.02, respectively). In patients who underwent VBG and GB, males had significantly lower preoperative EW % (Student t = -4.86, p < 0.001, and Student t = 4.69, p < 0.001, respectively), and postoperative mean of the average EWL % (Student t = -2.43, p = 0.016, and Student t = -3.33, p = 0.002, respectively) than females. In patients who underwent RYGB, there were no differences in the preoperative EW % (t = -1.03, p = 0.309) or the mean of the average EWL % (t = 0.406, p = 0.688). The simple linear regression model used to explain the variability in EWL %, accounted for by the variability in the preoperative EW %, was significant (F = 180, p < 0.001). Analysis of the residual errors in predicting the EWL % revealed no significant difference between males and females after VBG and after RYGB (t = 0.117, p = 0.907 and t = 1.052, p = 0.3, respectively), while it was significant after GB (t = -2.999, p = 0.003).

CONCLUSION

From our experience, we suggest that GB not to be offered as a first choice for obese male patients.

Tracheo-oesophageal compression due to massive spontaneous retropharyngeal haematoma

Spontaneous retropharyngeal haematoma and dissecting intramural haematoma of the oesophagus are two distinct, but rare, phenomena. We describe the first case of complete tracheo-oesophageal obstruction due to spontaneous retropharyngeal haematoma presenting with chest pain and dysphagia. Rapid imaging allowed life-saving transfer to the regional specialist centre, with immediate surgical intervention. The importance, aetiology and clinical features of both diagnoses are discussed.