bluuebunny/crossref_metadata_2025_split huggingface dataset:
O114: Enhancing palliative oesophageal cancer treatment pathway prediction and prognostication through machine learning models
Authors: Thavanesan Navamayooran , Parfitt Charlotte , Bodala Indu , Walters Zoë , Ramchurn Sarvapali , Underwood Timothy , Vigneswaran Ganesh 
Published: March 2024

Abstract

Introduction
Non-curative treatment plans comprise the majority of Oesophageal Cancer (OC) decision-making by Multidisciplinary Teams (MDTs), operating under significant caseload pressures. Machine Learning (ML) can semi-automate, streamline, and standardise these decisions to predict treatments and prognosticate for new patients. We present ML models which predict treatment decisions and prognostication in palliative OC patients.

Methods
Using clinicopathological data from 437 palliative OC cases treated at a single tertiary centre over 12 years, we trained several ML algorithms (Multinomial Logistic Regression [MLR], Random Forests [RF], Extreme Gradient Boost [XGB], Decision Tree [DT], and Random Survival Forests [RSF]) to predict treatment pathways (best supportive care, chemotherapy, radiotherapy, palliative stent, or stent plus oncological adjunct) and survival prognoses. Model performance was evaluated using Area Under the Curve (AUC) for classifier models and C-index (1-concordance) along with calibration plots for the survival model. Additionally, the models were integrated into a web application for clinician-friendly usability.

Results
Mean AUCs for the classifier models were: MLR 0.801±0.090, RF 0.806±0.078, XGB 0.817±0.079 and DT 0.762±0.108. Mean C-Index for the RSF survival model was 0.330±0.018 while calibration curves showed good calibration within the first 6-12months (median survival for the cohort was 6.31 months (range 0.1-105.8 months)).

Conclusion
This study is the first use of ML to predict palliative treatment plans and offer prognostication for OC patients, seamlessly integrated into a user-friendly interface for real-time treatment pathway prediction. This offers significant potential to streamline MDT caseload and provide data-driven decision-support for clinicians counselling these patients.
O225: Oxygenated hypothermic machine perfusion (HMPO2) of the pancreas; a porcine circulatory death model to compare a ‘continuous’ and an ‘end-ischaemic’ approach
Authors: Elzawahry Mohamed , Fallon John , Nawaz Sameena , Hastoy Benoit , Clark Anne , Ploeg Rutger , Friend Peter , Hunter James 
Published: March 2024

Abstract
Pancreas and islet cell transplantation are used in the treatment of patients with diabetes complications. During static cold storage (SCS) ATP is depleted, and by-products of anaerobic respiration accumulate. Ischaemia-reperfusion injury (IRI) affects quantity and viability of islets and it is characterised by acinar necrosis, oedema, and endothelial disruption (graft pancreatitis). The introduction of HMPO2 in liver & kidney preservation has demonstrated a significant reduction in the consequences of IRI. Pancreas HMPO2 was shown to be feasible in pre-clinical studies. We aimed to compare a ‘continuous’ to an ‘end-ischaemic’ approach of HMPO2 in pancreases using a porcine circulatory death model. Porcine pancreases were either started on HMPO2 for the totality of the cold storage time (‘Continuous’ group, n=6) or for the last two hours of the cold storage time (‘End’ group, n=6). All pancreases then underwent normothermic reperfusion (NR) to mimic transplantation. Glucose stimulated insulin secretion (GSIS) was measured using Mercodia human insulin ELISA (n=3 in each group). Both groups had no significant change of wet-to-dry ratio during the experiment, despite an increase in gross weight. Flows were higher during NR in the Continuous group. Amylase, Lipase and LDH increased throughout the study for all pancreases and showed no statistically significant difference between both groups. The Continuous group had a significantly greater insulin secretion in response to glucose stimulation and followed a biphasic pattern. Continuous HMPO2 preserved islet function and was a superior mode of preservation, showing no statistically significant difference in oedema or markers of damage, with improved perfusion parameters.
O148: Unlocking Enhanced Immunity in Pancreatic Ductal Adenocarcinoma: Activins Interplay with CAF-Stroma Mechanisms
Authors: McCluney Simon , Park Danielle , Miller Daniel , Bloxham Robert , Mehic Merima , de Vries Emma , Wang Xuelu , Wilkinson Robert , Hunt James , Hyvonen Marko , Boeing Stefan , Sarker Debashis , Hill Caroline 
Published: March 2024

Abstract
SMAD4 is a tumour suppressor gene that is mutated in up to 60% of pancreatic ductal adenocarcinoma (PDAC) tumours. Activins are members of the TGF-b signalling superfamily which signal through SMAD4 and are generally associated with an oncogenic process, with differing effects on tumour and stromal cells, such as cancer associated fibroblasts (CAFs). We sought to further elucidate the role of activin within PDAC and perturb activin signalling in vitro and in vivo. Analysis was performed of publicly available human datasets alongside human and murine single-cell RNA-sequencing datasets to study the effect of activin expression on survival and tumourigenesis. We developed anti-activin monoclonal antibodies to perturb activin signalling in PDAC mice, with deep analysis of tumour composition including immune cells and CAFs via a multitude of basic science techniques. We demonstrated that circulating activin levels are higher in PDAC patients than in healthy volunteers, whilst activin overexpression is associated with reduced overall survival in PDAC patients. Activin was shown to be predominantly expressed by contractile (collagen-depositing) CAFs, as opposed to inflammatory CAFs. Activin expression co-localises with fibroblasts, and anti-activin antibodies can reduce the collagen content of dense PDAC tumours. Additionally, anti-activin antibodies led to a statistically significant increase in CD4 and CD8 T-cell infiltration into murine PDAC tumours. We have shown that activin is overexpressed in PDAC, and high expression is associated with a more aggressive disease process. Anti-activin antibodies can alter the composition of desmoplastic PDAC tumours and increase the immune infiltrate of these typically “immune cold” tumours.
O126: Non-invasive vagus nerve stimulation to reduce ileus after colorectal surgery: randomised feasibility trial and efficacy assessment
Authors: Chapman Stephen , Kowal Mikolaj , Helliwell Jack , Naylor Maureen , Pyrah Harriet , Mappa Georgia , Croft Julie , Farley Katherine , Stocken Deborah , Jayne David 
Published: March 2024

Abstract

Objective
Ileus is characterised by intestinal dysmotility after surgery. In preclinical models, vagus nerve stimulation reduces intestinal inflammation, preventing smooth muscle dysfunction and accelerating the return of gut function. This study explored the efficacy and feasibility of a definitive trial and implementation of non-invasive, electrical, vagus nerve stimulation (nVNS).

Design
A participant-blinded, multi-centre, feasibility trial of self-administered nVNS was performed. Patients undergoing colorectal surgery were randomised to four groups of pre- and post-operative treatment (A: nVNS/nVNS; B: nVNS/Sham; C: Sham/nVNS; D: Sham/Sham). Feasibility outcomes were participant recruitment, compliance, and blinding. Clinical outcomes were intestinal function and adverse events. Interviews with patients and clinicians explored barriers to feasibility and implementation. In an independent cohort, the effects of nVNS on serum IL-1b, IL-6, and TNFa were quantified at baseline, 24-hours, and 72-hours after surgery.

Results
Ninety-seven out of 125 (77.6%) eligible patients took part. The median compliance was 19 out of 20 stimulations (IQR: 17-20). The median time to pass stool was 4 (3-5), 3 (2-4), 2.5 (2-3.5), and 3 (2-4) days for groups A-D, respectively. The incidence of adverse events was similar across groups. Trends toward reduced pro-inflammatory mediators were observed after nVNS. Interviews with patients (n=19) demonstrated their motivation to contribute actively to their recovery and interviews with clinicians (n=10) revealed strong reciprocal support.

Conclusion
This study confirms the safety, feasibility, and support for nVNS after surgery. Research on nVNS should progress from its current focus on pre-clinical models to powered, dedicated assessments of clinical effectiveness.
O250: Blood Pressure Homeostasis and Hyper-perfusion Syndrome Following Carotid Surgeries
Authors: Acharya Yogesh , Hynes Niamh , Sultan Sherif 
Published: March 2024

Abstract

Objectives
We aim to compare blood pressure homeostasis in patients undergoing bilateral versus unilateral carotid surgeries. Our primary endpoints are the incidence of postoperative hypertension and hyperperfusion syndrome (HPS). Secondary endpoints are major adverse cardiovascular events and all-cause mortality.

Methods
All patients undergoing carotid endarterectomy (CEA) from 2003 to 2022 were reviewed. We performed 1230 carotid interventions, of which 690 procedures had ten years of follow-up.

Results
Both the unilateral (512) and bilateral (91) carotid interventions caused a significant acute elevation in blood pressure (p&lt;0.001). In unilateral carotid interventions, the mean SBP was 137 ± 19.90 mmHg preoperatively and 152 ± 25.80 postoperatively (p&lt;0.001). Smoking (p=0.007), hyperfibrinogenemia (p=0.004), emergency admission (p=0.005), ipsilateral carotid stenosis &gt;90% (p=0.022), and previous ipsilateral carotid intervention (p=0.003) were significantly associated with the development of postoperative hypertension. No incidence of HPS occurred in the unilateral group. In bilateral carotid interventions, the mean SBP was 138 ± 20.50 mmHg preoperatively and 159 ± 24.60 mmHg postoperatively (p&lt;0.001). Emergency admission (p=0.012) and plaque morphology (p=0.035) were significantly associated with postoperative hypertension. Three patients with bilateral carotid interventions had HPS (3.3%) and developed hemorrhagic stroke within 30 days. Multivariate analysis found postoperative stage II hypertension following bilateral carotid procedures to be an independent predictor of stroke (p=0.004). However, postoperative hypertension was not an independent predictor of myocardial infarction (p=0.475) and mortality (p=0.608).

Conclusion
Significant acute elevation in blood pressure occurred following carotid surgeries. We observed HPS post bilateral carotid interventions, with postoperative hypertension being an independent predictor of peri-operative stroke.
O92: Machine perfusion in liver transplantation; Cochrane review and meta-analysis
Authors: Tingle Samuel , Dobbins Joseph , Thompson Emily , Figueiredo Rodrigo , Mahendran Balaji , White Steve , Pandanaboyana Sanjay , Wilson Colin 
Published: March 2024

Abstract

Introduction
Several novel machine perfusion technologies have been developed which attempt to improve outcomes compared with ice-box static cold storage (SCS). We aimed to evaluate the effects of different methods of machine perfusion liver transplantation.

Methods
We used standard, extensive Cochrane search methods to identify randomised machine perfusion trials. Data extraction was performed independently by two authors. Pairwise random-effects meta-analysis was performed. We assessed bias using Risk of Bias 2 and used GRADE to assess certainty of evidence.

Results
We included seven randomised trials (1024 transplant recipients from 1301 randomised/included livers); four compared end-ischaemic hypothermic oxygenated perfusion (HOPE) with SCS, and three compared normothermic machine perfusion (NMP) with SCS. When compared with SCS, HOPE was associated with improvement in the following clinically relevant outcomes: graft survival (HR=0.45, 95% CI=0.23-0.87; P=0.02; high-certainty evidence), serious adverse events (OR=0.45, 0.22-0.91; P=0.03; moderate-certainty evidence) and clinically significant ischaemic cholangiopathy (OR=0.31, 0.11-0.92; P=0.03; high-certainty evidence). NMP was not associated with improvement in any of these clinically relevant outcomes, although evidence for these outcomes was low certainty. NMP was associated with improved utilisation compared with SCS (one trial found a 50% lower rate of organ discard; P = 0.008).

Conclusions
Where the decision has been made to transplant a DCD or marginal DBD liver, HOPE will provide superior clinically relevant outcomes compared with SCS alone (graft survival, adverse events, cholangiopathy). NMP appears to improve utilisation of grafts that would otherwise be discarded, but well-powered trials specifically designed to assess utilisation are required.
O254: Open Latarjet Procedure in Athletes With a Minimum of 5 Years Follow Up: An Analysis of Factors Associated With Success
Authors: Doyle Tom , Keogh Carl , Kilkenny Conor , Moore Thomas , Kearney Jack , Albersharah Bader , Khan Sami , Hurley Eoghan , Mullett Hannan 
Published: March 2024

Abstract

Introduction
The open Latarjet (OL) procedure has shown excellent return to play (RTP) and low recurrence in athletes but there is limited published evidence for long term outcomes. The purpose of this study was to evaluate the outcomes of athletes 5-years post-operatively following the OL procedure.

Methods
A retrospective review of athletes who underwent OL under a single surgeon with a minimum of 5-year follow-up was performed. Multi-linear regression models were used to evaluate factors affecting postoperative satisfaction, and SSV level.

Results
141 shoulder in 132 male athletes who underwent OL were included, with a mean age of 22.9 years, with mean follow-up of 71.5months. At final follow up, 93.7% were satisfied/very satisfied, and the mean SSV was 85.5. Overall, the rate of RTP was 91.3%, with 80.8% returning at the same level at a mean of 7.3months. There were 9 athletes (6.4%) who experienced further dislocation, all during collision sports. In total 10 (7.1%) athletes had a further operation, of which 3 (2.4%) were for recurrent instability. The mean SIRSI score was 82.1 ± 27.3, the mean Rowe score was 85.4, while the mean VAS score was 2.1. Linear regression revealed the SIRSI, VAS and Rowe score as well as RTP were significantly associated with SSV score. 90.6% of athletes reported they would undergo the procedure again were it required.

Conclusion
There was very high rate of satisfaction, with excellent patient-reported outcomes, low rates of recurrent instability and a high rate of return to play among athletes.
O138: Predictors of early recurrence of oesophagogastric adenocarcinoma after neoadjuvant FLOT
Authors: Dayanamby Abbienaya , Chmelo Jakub , Bradshaw Alexander , Phillips Alexander 
Published: March 2024

Abstract

Background
Although survival of patients with oesophagogastric adenocarcinomas has improved over the years, rates of cancer recurrence remain high. There is limited research on predictors for early recurrence (ER), especially in patients receiving FLOT chemotherapy. The aim of this study was to investigate ER and survival rates and identify risk factors of ER.

Methods
Patients receiving neoadjuvant chemotherapy with FLOT for oesophagogastric adenocarcinoma at single high-volume centre between August 2018 and October 2022 were evaluated for early recurrence defined as disease present within 1 year of surgery. Multivariable analysis was conducted to identify risk factors for ER. Patients who died in-hospital or within 90 days of surgery and those with positive longitudinal margin were excluded.

Results
169 patients were included. 92.9% and 41.4% of patients completed all four neoadjuvant and adjuvant cycles of FLOT respectively. 51 patients (30.2%) developed recurrence in the follow up period with 24 patients (14.2%) having ER. Recurrence free survival and overall survival at one year were 84.1% and 91.7% respectively. The estimated median survival after recurrence was 4.8 months. Extracapsular spread was found to be independent risk factor for ER (OR 6.507, 95% CI 1.964-21.556, p=0.002) in multivariable analyses together with ypN3 stage (OR 7.204, 95% CI 1.118-46.403, p=0.038).

Conclusions
The variables identified in this study may be helpful in determining patients at a higher risk of ER following curative surgery. Understanding these predictors may help tailor the follow up care of these patients, such as regular surveillance imaging, treatment, and frequency of reviews.
O220: The role of cardiopulmonary exercise testing in predicting sarcopenia after neoadjuvant chemotherapy and post-operative complications
Authors: Dayanamby Abbienaya , Chmelo Jakub , Convill James , Samake Maurice , Petrides George , Phillips Alexander 
Published: March 2024

Abstract

Background
Neoadjuvant chemotherapy (NAC) may contribute to sarcopenia development in patients with oesophageal and oesophagogastric junction (OGJ) adenocarcinoma. Preoperative cardiopulmonary fitness and sarcopenia are both variables which have been correlated with outcomes after major surgery. The aims of this study were to investigate if pre-operative cardiopulmonary exercise testing (CPET) variables were associated with radiological sarcopenia post NAC, and the effect of CPET variables on post-operative outcomes in sarcopenic patients.

Methods
Patients from a single high-volume tertiary centre diagnosed with oesophageal or OGJ adenocarcinoma between August 2015 and August 2022 were included. CPET variables and post-NAC CT scans to assess for radiological sarcopenia were evaluated. CPET variables included in statistical analyses were ventilatory equivalent for carbon dioxide (VE/VCO2), anaerobic threshold (AT) and peak oxygen consumption (VO2 peak).

Results
208 patients were included. Median VE/VCO2 was 29 in patients with sarcopenia post-NAC and 28 in non-sarcopenic patients (p = 0.009). Other CPET variables were not associated with sarcopenia post NAC. Within the sarcopenic group, CPET variables were not associated with post-operative complications. Within the whole cohort, increased VE/VCO2 or decreased VO2 peak correlated with a longer hospital stay (p=0.043 and p=0.012 respectively), and an association was observed between VE/VCO2 and Clavien-Dindo grade of complications (p=0.019).

Conclusions
VE/VCO2 was associated with sarcopenia post NAC in patients with oesophageal and OGJ adenocarcinoma. Further analysis with a larger sample size might help establish this, which could be helpful in identifying and targeting patients at higher risk of sarcopenia and post-operative complications.
O265: Laparoscopic Cholecystectomy in Class III (Morbid) Obesity
Authors: Warrell Daniel , Oh Ke En , Pessoa Luiza , Manson David , Nageswaran Haritharan 
Published: March 2024

Abstract

Background
High body-mass index (BMI) has been associated with increased operative-time, conversion to open surgery, and poorer perioperative outcomes. Criteria for day-surgery often includes BMI, with centers excluding patients with BMI&gt;40kg/m2. However, as cholecystectomies are routinely performed laparoscopically with low complication rates in patients with higher BMI, this cut-off is being questioned.

Objectives
To examine outcomes of Laparoscopic Cholecystectomy in patients with increased BMI, particularly when comparing patients with morbid-obesity (Class-III;BMI&gt;40 kg/m2) to those with lower BMI.

Methods
Data was collected between 01/01/2022 and 31/07/2023 from hospitals throughout the Aneurin-Bevan University Health-Board, South-Wales, UK. Data on BMI, surgical indication, surgical duration, length of admission, and 30-day complications, amongst others was collected.

Results
This study included a total of 915 patients, 77.92%female 22.08%male. Patients were placed into 5 BMI categories: BMI&lt;25(n=98),25-29(n=255),30-34(n=253),35-39(n=176), and&gt;40(n=133). Median BMI was 31kg/m2, median surgical duration was 79-minutes, length of stay 0-days, the complication rate was 7.3%. There were two 30-day mortalities, one in each of BMI categories &lt;25 and 25-29. Comparing patients with BMI&gt;40 with others showed a significantly higher surgical duration (median 90.05mins vs83.5mins;p=0.045) but no difference in complications including bile-leak (2.3%vs1.8%;p=0.1823), significant bleed (0.7%vs0.4%;p=0.4779) or bile-duct injury (0%vs0.1%;p=0.4060). Due to existing day-surgery criteria, there was significantly increased length of admission in this group (median 1vs0 days;p=0.00).

Conclusion
This retrospective study finds Laparoscopic Cholecystectomy safe in patients with Class-III obesity with no increased association with intraoperative or post-operative complications. Criteria for day-surgery based solely on BMI&gt;40 appears inappropriate.
O65: Extremity Trauma in the UK (UK): Vascular Interventions and Surgery in Trauma Audit (VISTA)
Authors: Hurndall Katherine-Helen , Leatherby Robert , Tai Nigel , Glasgow Simon , Davenport Ross 
Published: March 2024

Abstract

Background
Extremity injury is the commonest form of vascular trauma but currently there is no national surgical surveillance of operative management and amputation rates. Vascular injury impacts both the young and elderly, with time critical, trauma specific intervention key for limb salvage.

Methods
Subgroup analysis of a six-month multicentre, prospective audit of vascular injuries to examine procedures for extremity vascular trauma at 27 UK Major Trauma Centres conducted by the National Trauma Research & Innovation Collaborative and Vascular & Endovascular Research Network.

Results
There were 153 extremity vascular injuries (n=120 patients: 66 upper limb, 81 lower limb) with 92 primary interventions performed (n=86 open: primary repair, bypass or ligation vs. n=6 endovascular). The median age of operated patients was 36 (IQR: 22.5 - 52) years and 74% were male. 51% of injuries operated upon were secondary to blunt trauma with concomitant orthopaedic injury in 33%. Median time to intervention was 169 (IQR: 112 - 371) minutes with a consultant vascular surgeon present in 84% of cases. Overall, there were n=16 amputations: 7% primary and 11% secondary in operative cases. The median age for amputation was 41.5 (IQR: 36 - 52) years.

Conclusion
Extremity vascular interventions, regardless of aetiology, require national surveillance to assess outcomes and identify targets for improved limb salvage across all UK vascular and trauma networks.