bluuebunny/crossref_metadata_2025 huggingface dataset:
O266: Transcriptomic signature from spatially inferred histologically benign ancestral clone predicts high risk prostate cancer
Authors: Anbarasan Thineskrishna , Fiegel Sandy , Yin Wencheng , Mills Ian , Lamb Alastair
Published: March 2024

Introduction

Prostate cancer (PCa) is a multifocal disease driven by heterogenous spatial and temporal branching evolution of tumour clones. Spatial transcriptomic analysis has revealed, clonally distributed copy number alterations even in histologically benign regions. We aim to evaluate if the genetic signature comprised within these genetically aberrant histologically benign regions, or “ancestral clones” may predict presence of high-risk disease.

Methods

Fresh-frozen, radical prostatectomy specimen was profiled using the 10x Genomics Visium Spatial Gene Expression platform. Via hierarchical clustering, spatial tumour clonal relations were inferred. Differentially expressed genes (DEGs) between high-grade tumour and histologically benign ancestral clones were identified. DEGs (|log2FC|>0.75) were input into a LASSO regression algorithm with normalised mRNA expression of normal adjacent tissue from the TCGA PCa database to train a genetic risk model to predict presence of high risk PCa (Gleason>8). Derived risk score was validated on an external cohort (GSE21032).

Results

A total of 683 DEGs were identified. These were enriched for organic acid metabolic pathways. Regression analysis on 57 normal adjacent tissue samples from TCGA PCa dataset was performed to develop a predictive model comprising of 3 genes (SLC22A3, CRIP2, LSAMP). External validation of the genetic risk score on matched histologically benign tissue from 131 patients, had good performance for prediction of high-risk PCa (AUC 0.807; 95% CI 0.693-0.921).

Conclusion

Our model has good performance for predicting high-risk PCa from matched normal tissue. Developed genetic risk score has translational potential to improve detection of unsampled clinically significant prostate cancer from histologically benign biopsy cores.
O203: HLA Matching Between Donors and Recipients Improves Clinical Liver Transplant Graft Survival
Authors: Otunla Afolarin , Nabulsi Sarah , Salciccioli Justin , Marshall Dominic , Villani Vincenzo , Shanmugarajah Kumaran , Shalhoub Joseph
Published: March 2024

Background and Aims

The importance of human leukocyte antigen (HLA) matching between liver transplant donors and recipients on graft survival remains unclear and is not a clinical consideration in liver transplantation. This study aimed to determine the relationship between HLA matching and liver graft survival using a large-scale multi-center database (UNOS/OPTN) and multivariate logistic analysis. The secondary aim was to determine whether this relationship was influenced by transplant indication and donor status.

Methods

This retrospective observational analysis was performed using 22,702 liver transplant recipients from the UNOS/OPTN database. Patients were divided into two groups based on number of HLA mismatches (0-3 mismatches vs 4-6 mismatches), and then subcategorized by indication and donor status. Risk-adjusted outcomes were assessed by multivariate Cox analysis adjusting for donor and recipient characteristics and visualized using Kaplan-Meier survival curves.

Results

Allograft survival and risk of acute rejection were associated with degree of HLA mismatch. This association between HLA mismatch and graft survival persisted in individuals who underwent transplant for hepatitis, metabolic, drug toxicity and congenital indications. Donor status influenced the relationship between HLA mismatch and graft survival. Graft survival in DBD recipients was longer than in DCD in the 4-6 HLA mismatch group, whereas no significant difference was found in the 0-3 HLA mismatch group.

Conclusion

HLA mismatch significantly reduced graft survival and increased risk of acute rejection. This association was noted only in specific indications. These findings are of potential clinical relevance to organ allocation, allograft matching algorithms, immunosuppression protocols and transplant surveillance.
O236: The Impact of HLA Matching on Pancreas and Simultaneous Pancreas-Kidney (SPK) Transplantation Outcomes
Authors: Nabulsi Sarah , Otunla Afolarin , Salciccioli Justin , Marshall Dominic , Villani Vincenzo , Shanmugarajah Kumaran , Shalhoub Joseph , Dolan Dan
Published: March 2024

Background

This study evaluates the controversial impact of human leukocyte antigen (HLA) matching on pancreas graft survival and acute rejection.

Methods

Utilizing a large-scale multi-center database (UNOS/OPTN), we identified 8,005 pancreas and 7,850 simultaneous pancreas-kidney (SPK) transplant patients. Patients were classified into HLA matched (0-3 mismatches) and mismatched (4-6 mismatches) groups. Subsequently, utilizing multivariate Cox analysis, we evaluated risk-adjusted outcomes, represented through Kaplan-Meier survival curves. We also examined differences in graft survival and acute rejection based on transplant type (SPK or pancreas alone) within the same HLA mismatch group.

Findings

There were no significant differences in pancreas graft survival or acute rejection observed between HLA matched and mismatched groups for both pancreas and SPK transplant recipients (P > 0.05). However, among HLA mismatched patients, pancreas patients exhibited a 629-day lower pancreas graft survival than SPK patients (3774 vs. 4403 days, P < 0.001) and had a higher likelihood of experiencing acute rejection post-transplant (P < 0.001). Similarly, within the HLA matched groups, pancreas patients showed lower graft survival compared to SPK patients (3774 vs. 4403 days, P < 0.001); however, their acute rejection rates did not significantly differ (P > 0.05).

Interpretation

Although HLA matching was not associated with improved pancreas graft survival or a reduction in acute rejection, the results suggest a potential protective effect of the kidney in SPK transplants against the consequences of HLA mismatching. This underscores the clinical significance of considering the kidney component in donor-recipient matching for pancreas transplantation.
O91: The Negative Impact of Transplant Liver Steatosis is Significantly Exaggerated in Donation Following Circulatory Death: A National Cohort Study
Authors: Ho Ning Xuan , Tingle Samuel James , Mahendran Balaji , Bramley Rebecca , Thompson Emily , Amer Aimen , Figueiredo Rodrigo , McPherson Stuart , White Steve , Wilson Colin H
Published: March 2024

Introduction

The demand for liver transplantation is rising, as is the prevalence of steatotic liver disease. Steatotic grafts have inferior outcomes post-transplantation, perhaps related to increased sensitivity to ischaemia-reperfusion injury. We aimed to formally evaluate whether the impact of steatosis differs in grafts donated following brainstem (DBD) versus circulatory death (DCD).

Methods

The NHS registry on adult liver transplantation was reviewed retrospectively (2006-2019). We used multiple-imputation for missing data, and adjusted regression models with interaction terms to compare the impact of donor graft steatosis (visually-assessed) on transplant outcome in DCD versus DBD.

Results

9217 adult recipients of deceased donor grafts were included (DBD=7349; DCD=1868). Multivariable cox regression revealed that the negative effects of moderate or severe steatosis on graft survival were significantly different in DCD and DBD livers (interaction P=0.011 and P=0.043). The largest impact was in DCD livers (aHR=1.851, 1.296-2.645, P=0.001 for moderate and aHR=5.426, 1.723-17.090, P=0.004 for severe steatosis). In contrast, steatotic livers did not suffer inferior longer-term graft survival in the DBD cohort, despite inferior early outcomes.

Conclusion

The impact of steatosis on transplant outcome differs significantly based on donor type, with a much larger negative impact in DCD, proving that steatotic livers are specifically sensitive to the DCD process. This highlights a high-risk group which should be the target of novel therapeutics to allow this growing sector of the donor pool to be safely utilised. In contrast, moderate-severe steatosis does not impact longer term outcome in DBDs, and such grafts can be transplanted with excellent outcome.
O228: Do additional faecal immunochemical tests (FIT) provide more reassurance that colorectal cancer is not being missed? Results from the repeat FIT (RFIT) study
Authors: Farkas Nicholas , Palyvos Lampros , O’Brien James , Yu Kai Shing , Whyte Martin , Jourdan Iain , Rockall Timothy , Benton Sally
Published: March 2024

Introduction

Faecal immunochemical testing (FIT) is highly sensitive for colorectal cancer (CRC) detection. NICE recommend a single FIT in primary care for urgent cancer referrals. Little evidence regarding the benefit of repeating FIT exists. The repeat FIT (RFIT) study aims to determine whether second and third FIT provide reassurance and improve CRC or significant bowel disease (SBD) identification.

Methodology

Prospective observational cohort study (UK HRA and REC approval). Patients recruited from urgent referrals returned three FIT and underwent colonoscopy. χ2 test compared categorical data. Accuracy (sensitivity/specificity/PPV/NPV) reported for one, two and three FIT (95% CI). Three negative FIT (<10µg Hb/g) cohorts (single, double, triple) were compared with positive cohorts (one or more FIT ≥10µg Hb/g). SBD and CRC detection rates were compared by strategy. Median FIT was calculated for pathology.

Results

460 patients included (mean age=66.8yrs, M:F 233:227, CRC=23, SBD=80). For single, double and triple negative FIT, CRC sensitivity remained static (95.7%), specificity (44.6%,40.7%,38.4%) and NPV decreased (99.5%,99.4%,99.4%). For SBD, sensitivity increased (78.8%,83.8%,86.3%), specificity decreased (47.4%,43.7%,41.6%) and NPV increased (91.4%,92.7%,93.5%). In single, double and triple positive FIT cohorts, CRC detection was 8.3%,16.1%, 20.9%. CRC mean FIT was 150µg Hb/g, <6 for benign pathology.

Conclusion

The presence of negative FIT (single/multiple) reduces likelihood of CRC/SBD. Multiple FIT strategy provides greater differentiation and improved CRC/SBD detection compared to single FIT. Repeat FIT offers a safe, cost-effective strategy for triaging symptomatic patients. This may provide reassurance, or safely allow investigation on non-urgent pathways.
O142: Current clinical applications and limitations of graft augmentation in rotator cuff repair: a systematic review
Authors: Jin Janice
Published: March 2024

Background

Rotator cuff tears (RCTs) are a leading source of chronic and acute shoulder pain globally, with causes spanning from tendon degeneration to traumatic injury. Especially prevalent in the aging population, RCTs have a significant retear rate despite surgical intervention, and recent years have seen an increase in the use of grafts in surgery to address many of the clinical issues previously encountered in tendon-healing.

Objectives

To compare the effectiveness of various grafts in graft-augmentation surgery for full-thickness rotator cuff tears, assessed with functional and clinical outcomes.

Selection criteria

Adult patients with MRI-diagnosed full-thickness RCT and subsequently underwent graft-augmentation surgery; followed-up >1year, with assessment for retear and quantitative clinical outcomes.

Results

32 primary studies, mean follow-up of 2 years and total of 1052 patients were included. The effectiveness of graft-augmentation was assessed using retear rate, ASES, Constant, UCLA and VAS. Graft-augmentation significantly improves all functional and clinical scores (p<0.05), and decreases retear rate to an average of 18.5% >1year post-surgery (p<0.0001), with no significant difference in effectiveness between the 4 different types of grafts. (p>0.05). No significant difference in outcomes was found in graft-augmentation between different tear sizes.

Conclusions

Graft augmentation for RCTs shows significant improvements in clinical and functional outcomes, and significantly lowers retear rate compared to conservative treatment or surgery without graft augmentation. The choice of graft has been shown to be of less importance than the clinical decision to use surgical-intervention with graft-augmentation, which applies to full-thickness tears of all sizes; both primary and revision tears.
O100: A novel bedside assessment of skeletal muscle wasting predicts treatment-related toxicity prior to major surgery – The Muscle Ultrasound in Esophagogastric Cancer (MUSEC) study
Authors: Casey Patrick , Powell Arfon , McPhee Jamie , McSweeney Donal , Weaver Jamie , Redfern Jennifer , McLaughlin John , Ang Yeng , Sultan Javed
Published: March 2024

Sarcopenia is an important prognosticator during treatment for Oesophagogastric (OG) cancer. Despite this, sarcopenia is not routinely measured in clinical practice due to resource availability. Ultrasound is emerging as a potential tool to quantify muscle mass and quality and might predict treatment-related complications. Skeletal muscle ultrasound has not been investigated in patients undergoing cancer treatment. Patients receiving treatment for OG cancer (chemotherapy plus surgery) were prospectively recruited. Ultrasound was performed at 4 time points during treatment. Primary outcome was a measurable change in skeletal muscle. Secondary outcome measures included correlation with gold-standard measures of muscle mass (CT skeletal muscle index (SMI)), and the association between sarcopenia on ultrasound and treatment-related complications. Fifty patients were recruited. Significant deterioration in quadriceps muscle thickness, cross sectional area, rectus femoris echointensity, and ultrasound sarcopenia index (USI) was observed during chemotherapy. USI showed moderate correlation with CT SMI (r = -.511, p=0.001) with ultrasound classifying more patients as sarcopenic (37% vs 18%, p=0.001), plus detecting a greater magnitude of muscle loss during chemotherapy (-20.2 ±18% vs -6.5 ±7.4%, p=<0.001). USI correlated better with physical function (1-minute sit to stand) compared to CT SMI (r .589, p=<0.001 versus r .149, p=0.169). Ultrasound-defined sarcopenia at baseline was associated with a higher incidence of dose limiting chemotoxicity and severe chemotoxicity but did not post-operative complications. Further validation studies are required, but bedside muscle ultrasound could provide an effective bedside assessment of muscle health and identifies a higher proportion of patients at risk of chemotoxicity prior to major surgery.
O64: Aortic Trauma in the UK (UK): Vascular Interventions and Surgery in Trauma Audit (VISTA)
Authors: Hurndall Katherine-Helen , Leatherby Robert , Tai Nigel , Davenport Ross , Glasgow Simon
Published: March 2024

Background

In the UK, the incidence, treatment strategies and clinical outcomes for aortic injury are unknown. Stent graft sizing can be challenging in the acute trauma setting which may increase the risk of stent graft complications. VISTA aimed to describe the UK burden and treatment of aortic trauma.

Methods

Subgroup analysis of a six-month multicentre, prospective audit of vascular injuries at 27 UK Major Trauma Centres by the National Trauma Research & Innovation Collaborative and Vascular & Endovascular Research Network.

Results

In total, 58 aortic injuries (43 thoracic, 15 abdominal) with 24 interventions (n=23 TEVAR) were analysed. The median age of TEVAR patients was 46 (IQR: 27 - 59) years and 92% were male. The median time to intervention was 288 (IQR: 208 - 722) minutes and 75% of cases were performed for grade 3 and 4 aortic injuries with one simultaneous carotid-subclavian bypass. A consultant vascular surgeon was documented as present in 75% of cases and the post-procedure mortality rate was 8%.

Conclusion

TEVARs performed for vascular trauma setting are currently excluded from the National Vascular Registry. UK centre performance, device surveillance and long-term outcomes for this patient cohort requires national monitoring to assure patient safety and drive care quality improvements.
O57: Tailored risk assessment and forecasting in intermittent claudication using machine learning (TRAFIC-ML)
Authors: Ravindhran Bharadhwaj , Prosser Jonathon , Mishra Bhupesh , Lathan Ross , Carradice Daniel , Smith George , Thakker Dhaval , Chetter Ian , Pymer Sean
Published: March 2024

Introduction

Guidelines recommend cardiovascular risk reduction and supervised exercise therapy as the initial treatment for patients with intermittent claudication(IC). However, implementation challenges and poor patient compliance lead to significant variation in management and therefore outcomes. We propose a precise machine learning derived decision support system that aims to provide personalised outcome predictions across different management strategies.

Methods

Feature selection was performed using the least absolute shrinkage and selection operator method. The model was developed using a bootstrapped sample of 10,000 patients based on 255 patients from our vascular centre. The model considered 27 baseline characteristics, compliance to best medical therapy/smoking cessation and treatment strategy. The model was validated using a separate dataset of 254 patients. This model was then used to build a prototype interactive decision support system which was evaluated using calibration curves, decision curve analyses and area under the receiver operator characteristic (AUROC) curves.

Results

The AUROC curves demonstrated excellent discrimination for the risk of progression to chronic limb threatening ischaemia at two years(0.892) and five years(0.866) and likelihood of major adverse cardiovascular events(0.836), major adverse limb events(0.891) and revascularisation(0.896)within 5 years, regardless of the treatment strategy. Calibration curves demonstrated good consistency between predicted and actual outcomes and decision curve analyses confirmed clinical utility. The tool maintained an accuracy of >80% and an effect size of >0.5.

Conclusion

Our decision support system successfully predicts outcomes in IC regardless of treatment strategy, offering potential for improved risk stratification and patient outcomes.
O124: Investigating the Immuno-modulatory Effect of Adipose-derived Stem Cells in Radiation- Induced Fibrosis
Authors: Cui Xiangmei , Wai Jasmine , Frommer Marvin , Langridge Benjamin , Butler Peter
Published: March 2024

Background and Introduction

Radiation-induced fibrosis (RIF) is a complication of radiotherapy in the treatment of head and neck carcinoma with high patient morbidity. Autologous fat grafting is a viable method to treat RIF, and adipose-derived stem cells (ADSC) were found to be one of the main components to contribute to that effect.

Method

Experimental group consists of irradiated human-derived fibroblasts (iHDF) in vitro with the control group unexposed to radiation. Both groups were then inoculated with ADSC-controlled media and co-culture with ADSC, whilst levels of key immunomodulators expressed by iHDF cells were obtained and measured via enzyme-linked immunosorbent assay (ELISA) and real-time reverse transcription-polymerase chain reaction (RT-PCR).

Results

There is marginal decrease in CCL2 concentrations in co-cultured iHDF samples compared to untreated iHDF samples (p = 0.0006). There is a slight increase in CCL3 levels in iHDF co-culture samples compared to untreated iHDF samples (p = 0.0247). iHDF co-culture samples shows a statistically significant increase in IL-8 levels when compared to untreated samples of iHDF (p = 0.027). Col1A1 is reduced in iHDF samples when compared to control groups.

Discussion

CCL2 is implicated in recruitment of ADSCs to target sites. The increase in IL-8 secretion in ADSC samples is implicated in the pro-angiogenic properties of ADSC secretions to encourage healing in fibrotic tissue.

Conclusion

ADSC was demonstrated to have anti-fibrotic capabilities by promoting pro- angiogenic factors, however, experimental evidence points to a simultaneous increase in pro-inflammatory factors. Future works required to further investigate in vivo effects of ADSC.
O218: Biomechanical and Ergonomic Risks Associated with Cervical Musculoskeletal Dysfunction amongst Surgeons: A Systematic Review
Authors: O'Reilly Kasie , McDonnell Jake , Dolan Roisin
Published: March 2024

Introduction

Surgeons are at high risk of developing musculoskeletal symptoms due to a range of factors including, maladaptive positioning, surgical ergonomics, and surgeon characteristics. Cervical muscle strain and biomechanical load is most prevalent due to repetitive motions and prolonged static neck positioning1. However, recommendations to improve cervical health of surgeons are limited. This issue is apparent through reports of prevalence between 10 – 74.4% among surgeons2,3. The aim of this systematic review is to provide an objective assessment of the clinical evidence available and a descriptive analysis of the effects of kinematics and surgical ergonomics on the prevalence of surgeons’ cervical musculoskeletal pain.

Results

A total of 2474 articles were identified on initial search, of which 1046 were duplicates and were removed from review. Abstracts and full texts remaining were then screened, with 9 studies included in the final qualitative analysis. The use of loupes, open surgery and excessive neck flexion (> 30 degrees) were associated with cervical dysfunction. Comparison of study outcomes was challenging due to heterogeneity within study methods and the paucity of methodological quality. This precluded formal meta-analysis.

Conclusion

The current literature assessing ergonomic and biomechanical factors predisposing surgeons to cervical musculoskeletal dysfunction is insufficient to provide reliable guidance for clinicians. Although the literature has identified factors that contribute to work-related cervical dysfunction, few have attempted to evaluate interventions for improved surgical ergonomics. An objective assessment of interventions that promote postural correction with the aim to improve neck pain scores in surgeon cohorts is warranted.
O24: Triggering Change: Evaluating Minimally Invasive Techniques in the Pandemic-Era Hand Surgery in Malaysia
Authors: Nagy Eva , Tay Jing Qin , Tay Jing Shin , Lim Zhuang Li
Published: March 2024

Aims

This study aimed to compare outcomes of open surgical release versus ultrasound-guided and anatomical landmark-guided percutaneous release techniques for trigger finger treatment during the COVID-19 pandemic (year 2020-2022) at a single centre in Malaysia.

Methods

A retrospective review was conducted for 44 patients (94 digits) who underwent open surgical release (OS, n=52 digits), ultrasound-guided percutaneous release (UPR, n=30 digits), or anatomical landmark-guided percutaneous release (APR, n=12 digits) for trigger finger from 2020-2022. Outcomes assessed included post-operative pain, triggering recurrence, time to return to work/activities, patient satisfaction, and complications.

Results

Patients undergoing percutaneous release had expedited return to work/activities (3 days) compared to open surgery (20 days) (p<0.0001). No UPR/APR patients reported persistent pain at 3 months versus 13.5% of OS patients. Recurrence rates were comparable between modalities (1.9% vs 2.4%). Patient satisfaction was similar across OS/UPR/APR groups (4.4 vs 4.3 vs 4.4). Complication risks were lower with percutaneous techniques.

Conclusions

During the COVID-19 pandemic, percutaneous trigger finger release facilitated swifter rehabilitation and reduced hospital visits versus open surgery. The percutaneous approaches demonstrated clear benefits especially relevant for strained healthcare systems, including neater post-operative recovery, diminished long-term discomfort, and lower complication risks. Percutaneous release has considerable advantages and merits wider embrace.
O184: Predictive value of pre-treatment circulating inflammatory response markers in the neoadjuvant treatment of breast cancer: a systematic review and meta-analysis
Authors: Dowling Gavin , Daly Gordon , Hegarty Aisling , Hembrecht Sandra , AlRawashdeh Maen , Bracken Aisling , Toomey Sinead , Hennessy Bryan , Hill Arnold
Published: March 2024

Purpose

Systemic inflammatory response markers have been found to have a prognostic role in several cancers, but their value in predicting response to neoadjuvant chemotherapy is uncertain. A systematic review and meta-analysis of the literature was carried out to investigate this.

Methods

A systematic search of electronic databases was conducted to identify studies that explored the predictive value of circulating systemic inflammatory response markers in patients with breast cancer prior to commencing neoadjuvant therapy. A meta-analysis was undertaken for each inflammatory marker where three or more studies reported pathological complete response (pCR) rates in relation to the inflammatory marker. Outcome data were reported as odds ratios (ORs) using 95% confidence intervals (CIs).

Results

Forty-nine studies were included in total, of which 42 were suitable for meta-analysis. Lower pre-treatment neutrophil-lymphocyte-ratio (NLR) was associated with an increased rate of pCR (pooled OR 1.66, 95% CI 1.32 to 2.09; P<0.001). Lower white cell count (WCC) (OR 1.96, 95% CI 1.29 to 2.97, P=0.002) and lower monocyte count (OR 3.20, 95% CI 1.71 to 5.97) were also associated with pCR. Higher lymphocyte count was associated with increased pCR rate (OR 0.44, 95% CI 0.30 to 0.64, P<0.0001).

Conclusion

The present study found pre-treatment NLR, WCC, lymphocyte count and monocyte count of value in the prediction of pCR in the neoadjuvant treatment of breast cancer. However, further research is required to determine their value in specific breast cancer subtypes and to establish optimal cut-off values, prior to their adoption in clinical practice.
O52: Empowering Medical Students and Early Career Surgeons in Critical Appraisal of AI Research: Design and Evaluation of a Pilot Course
Authors: Ngai Victoria , Jalal Arif Hanafi Bin , Hanrahan John Gerrard , Das Adrito , Khan Danyal Z , Cotton Elizabeth , Sharela Shazia , Stasiak Martyna , Marcus Hani J , Pandit Anand S
Published: March 2024

Introduction

As artificial intelligence (AI) plays an increasing role in surgical practice, there is a need for surgeons to understand and evaluate literature surrounding the use of AI. There is currently a lack of training in this area for medical students and surgical trainees. We designed and assessed the impact of a short educational course.

Methods

A two-day online course was held, consisting of lectures and small-group discussions surrounding the fundamentals and appraisal of AI literature with a focus on neurosurgery. Participants included individuals working in neurosurgery (trainees, consultants and researchers) and medical students interested in surgery. A Qualtrics survey was distributed before and after the course. Participants’ knowledge was assessed before and after using 15 multiple-choice questions. Individuals allocated to the course’s waiting list completed a control survey.

Results

62 participants (33 participants, 29 waitlist controls) attended the course and completed the pre-course survey. After the course, participants significantly improved in their knowledge of AI (mean difference = 3.86, 95% CI = 2.97-4.75, p-value < 0.0001) and confidence in critically appraising AI literature (p-value = 0.002). Differences in knowledge (mean difference = 3.15, 95% CI = 1.82-4.47, p-value < 0.0001) and confidence (p-value < 0.0001) were also found when compared to the control group. Significant differences were maintained when medical students or researchers were excluded from analysis.

Conclusion

Short courses that are tailored to the specialty and experience of surgical trainees and medical students can improve their understanding of AI, without the need for in-depth technical knowledge or programming skills.
O85: Discrepancy Rates in Acute Abdominal CT: A Comparison of In-House and Remote Reporting to Intra-Operative Laparoscopic and Laparotomy Findings
Authors: Redman Ishtar , Ntampakis Georgios , Alamin Amin , Mohan Anand , Bananis Kyriakos , Drymousis Panagiotis
Published: March 2024

Non-traumatic abdominal pain is a common emergency presentation frequently managed by General Surgeons. Abdominopelvic computed tomography (CT) scans are the most popular imaging modality in this context. In many hospitals, the rising demand for urgent and emergent scans out-of-hours has necessitated the outsourcing of this service to teleradiology companies whereby reports are generated at sites remote from the image acquisition. The primary aim of this study was to determine the discrepancy rates of pre-operative CT imaging by source (Teleradiology compared to in-house). This was a retrospective monocentric study conducted at a busy district general hospital over a seven-month period. Patient demographic data, operative notes, and radiology reports (by source) were collated for all patients aged ≥ 16 years presenting with atraumatic abdominal pain who underwent abdominopelvic CT with subsequent surgical intervention (laparoscopy and/or laparotomy). 71 patients were identified by initial screening, 10 patients (11 scans) met the criteria for a ‘major’ discrepancy. Overall discrepancy rates were calculated at 5.6% for scans reported off-site compared to 9.9% for reports generated by in-house radiologists, P = 0.192 (p < 0.05), OR 2.625 (95% CI 0.6915 to 8.595). This study demonstrated lower discrepancy rates in scans reported remotely and can be used as the catalyst for improving aspects of in-house CT reporting.
O247: In vitro exposure of gastric cancer cell line AGS to the cannabinoid cannabidiol (CBD) results in cytotoxicity in a dose-dependent manner
Authors: Saleh Ahmed , Saha Arin , Dobbins Brian , Phillips Roger , Javid Farideh
Published: March 2024

Introduction

Current curative therapeutic regimens for gastric cancer combine chemotherapy with surgery, though this approach is associated with morbidity and mortality and relatively low long-term survival when compared to other solid organ and gastro-intestinal tumours. Cannabinoids are known to have anti-cancer properties in some tumours, though their role in gastric cancer is relatively unknown. This study aimed to determine if the non-psychoactive cannabidiol (CBD) induces cytotoxicity in the gastric cancer cell line AGS.

Method

The gastric cancer cell line AGS was maintained as per recommended guidelines. When cells reached 70% confluence, they were seeded in 96 well plates and treated with CBD or cisplatin at concentrations ranging from 0.2 μM to 100 μM or vehicle control. After 96 hours contact time, cell viability was assessed using a colorimetric cell viability assay (MTT assay). Experiments were repeated independently four times. Cell viability at each concentration was recorded and half maximal inhibitory concentration (IC50) was calculated. Results were expressed as the mean ± SE mean.

Results

Treatment with cisplatin induced significant cytotoxicity in a dose dependent manner with an IC50 concentration of 1.8 ± 0.3μM. Treatment with CBD also induced cytotoxicity in a dose dependent manner. Cytotoxic effects were observed with concentrations as low as 3.1μM (78% viability). The IC50 concentration for CBD was 10.2 ± 2.5 μM.

Conclusions

CBD induced significant cytotoxicity at micromolar concentration in stomach carcinoma cells. Further studies should be carried out to investigate the mechanisms of action that underpin the observed in vitro cytotoxic effect.
O248: Treatment of gastric cancer cell line AGS with cannabidiol (CBD) induces loss of mitochondrial membrane potential
Authors: Saleh Ahmed , Saha Arin , Dobbins Brian , Phillips Roger , Javid Farideh
Published: March 2024

Introduction

Cannabinoids have been shown to have anti-cancer properties for a variety of tumour sites; however, the mechanisms that underpin these effects are poorly understood. Apoptosis is implicated as the likely mechanism of action by which cannabinoids induce cell death. The loss of mitochondrial membrane potential (MMP) is observed in apoptotic cells and has been linked to induction of the apoptotic process. This study aimed to assess whether exposure to CBD induced loss of MMP.

Method

AGS cells were sub-cultured as recommended. When cells reached 70% confluence, they were treated with either control (ethanol), 5 µM, 10 µM or 20 µM CBD. After 24 hours, the MMP assay was performed using the NC-3000 advanced image cytometer to assess the mitochondrial uptake of JC-1 dye. Cells with a loss of mitochondrial membrane potential are represented as percentage of the total cell population and expressed as mean ± SE mean (N=3). The ANOVA test was used to determine statistical significance.

Results

Treatment with control induced loss of MMP in 8.4 ± 1.7% of cells. Treatment with 5 µM, 10 µM or 20 µM CBD induced a loss of MMP in 6.7 ± 1.4 %, 10.3 ± 2.2% and 44.7 ± 2.8 % of cells respectively. Treatment with 20µM CBD induced a statistically significant loss of MMP when compared to control (p<0.05).

Conclusions

AGS cells treated with CBD undergo loss of MMP. This finding could indicate that treatment is inducing apoptosis. Further investigations into apoptotic mechanisms are required to confirm the findings.
O101: Current guidelines on physical activity do not prevent skeletal muscle loss and physical decline prior to Oesophagogastric cancer surgery: a new benchmark for prehabilitation?
Authors: Casey Patrick , Powell Arfon , McPhee Jamie , McSweeney Donal , Redfern Jennifer , Moore John , McLaughlin John , Sultan Javed
Published: March 2024

Prehabilitation is being widely adopted to optimise physical health prior to surgery. However, there remains a lack of consensus regarding exercise type and intensity with current guidance extrapolated from generic, non-cancer populations. The WHO and American College of Sports Medicine (ACSM) recommend 600-1200 Metabolic Equivalent minutes (MET-mins) per week of physical activity (PA) but the effectiveness of this recommendation in cancer populations is unknown. Patients undergoing treatment for Oesophagogastric cancer were prospectively recruited. International Physical Activity Questionnaire (IPAQ) quantified PA at baseline and throughout treatment. Two cohorts were defined (lowPA and highPA) based on ACSM cut-off of 1200 MET-mins/week. Outcome measures were physical function (1 minute sit-to-stand, 1mSTS), CT muscle mass, chemotoxicity, and failure to complete planned treatment. 38 patients completed all study assessments (highPA n=20, lowPA n=18) with no difference in baseline characteristics or disease stage between groups. LowPA group showed declines in 1mSTS performance following chemotherapy, whereas the highPA group improved (mean difference -4 versus +10, p=0.001). Whilst both saw a decline in skeletal muscle mass, the lowPA group lost significantly more (mean difference -5.1 versus -1.8, p=0.007). There were trends towards a lower incidence of severe chemotoxicity (30% vs 61%, p=0.054) and failure to complete planned treatment (15% versus 28%, p=.33) in the highPA group. Whilst further research is required to define the most effective prehabilitation strategy, this study is the first to suggest a new benchmark to preserve muscle mass and function is higher than current guidelines and should be considered when developing prehabilitation recommendations.
O146: Investigating the cell-matrix interplay in fibrotic remodelling using renal 3D in vitro models
Authors: Upadhyay Anuja , Bakkalci Deniz , Cheema Umber , Loizidou Marilena
Published: March 2024

Introduction

The dynamic biophysical microenvironment of the renal extracellular matrix is integral in regulating tissue homeostasis. Matrix remodelling is an iterative process, which guides cell behaviour and pathological fibrosis occurs due to aberrant tissue repair. Fibrosis, characterised by the desmoplastic ECM deposition and tissue stiffening, is prominent in CKD and renal carcinomas. We engineered biomimetic 3D constructs to recapitulate cell-matrix interactions in fibrotic disease progression.

Methods

Soft collagen-I and laminin constructs (0.2%w/v) were engineered with renal cancer cells (786-O or ACHN) or renal fibroblasts (TK188). Plastic compression was used to generate dense collagen constructs, at 6%w/v collagen density. Mechanical properties were analysed using shear rheology. Gene expression of markers defining the healthy/diseased kidney matrix was determined using qPCR.

Results

Over 21 days, 786-O cancer cells softened the collagen matrix. Matrix degradation was supported by collagen-I downregulation and MMP7 and vimentin upregulation. Whereas metastatic cancer cells (ACHN) stiffened the dense matrix to ∼1.25kPa, with significant gene upregulation of collagen-I, collagen-IV and LOX. Fibrotic fibroblasts soften the dense matrix by ∼1kPa, with α-SMA and MMP9 upregulation. However, matrix stiffness significantly increases with cancer cell co-cultures.

Discussion

Renal cancer cells remodel their biophysical environment, altering the construct’s material properties. In our models, collagen density and stromal complexity influences cell behaviour, causing alterations in biomechanics and gene expression. These models can generate physiologically relevant stiffness, enabling investigation between key cell types and the physical environment. Drugs targeting MMPs and LOX will be used to determine if we can disrupt the fibrotic remodelling.
O21: ASSIST: Validation of a novel hybrid clinician-patient remote outcome measure for diagnosis of surgical site infection
Authors: Lathan Ross , Hitchman Louise , Ravindhran Bharadhwaj , Sidapra Misha , Walshaw Josephine , Long Judith , Totty Joshua , Carradice Daniel , Smith George , Chetter Ian
Published: March 2024

Introduction

Current remote methods of surgical site infection diagnosis have high specificity but lack sensitivity in diagnosis. This study evaluates the acceptability, reliability and validity of a novel hybrid clinician-patient remote outcome measure (ASSIST) for detecting SSI.

Methods

Patients completed the Bluebelle wound healing questionnaire (WHQ) at 30 days post-surgery and additionally submitted wound image(s). Images were reviewed two independent clinicians. Internal consistency of the unidimensional scale was assessed. Inter-rater and intra-rater reliability assessments were performed. Sensitivity and specificity for SSI discrimination against face-to-face CDC diagnosis were evaluated and receiver operator characteristic (ROC) curve plotted with calculation of the area under the curve.

Results

69 participants were included and no questionnaires contained missing items. The single scale showed strong Internal consistency (α = 0.9). Intra-rater reliability was good with intraclass correlation (ICC) of 0.818 (95% CI, 0.672-0.903, p<0.001). Inter-rater agreement was excellent (ICC 0.915, 95% CI 0.733-0.903, p<0.001). Sensitivity and specificity for SSI diagnosis were excellent at 91.7% and 97.6% respectively. Discrimination for SSI was high with an area under the receiver operating characteristic curve of 0.966 (95%CI 0.913-1.000).

Discussion

The ASSIST measure is acceptable, reliable, and valid for diagnosis of SSI. Implementation can be safely utilised in both patient-initiated follow-up or at pre-determined time points for safe post discharge surveillance.
O116: Comparing Virtual Reality versus Simulation to teach the assessment and management of acute surgical scenarios
Authors: Tran Mi-Tra , Ahmad Manal , Patel Kirtan , Argyriou Orestis , Davies Alun , Shalhoub Joseph
Published: March 2024

Introduction

Traditional apprenticeship-based surgical training presents with challenges, especially in acute scenarios. Simulation is the current gold standard but has its drawbacks. Virtual reality (VR) offers immersive three-dimensional computer-generated training scenarios and can connect users from various locations. We aimed to compare the performance of junior doctors to manage an acute surgical scenario using VR and mannequin-based simulation. We hypothesised that VR would be as effective as mannequin-based simulation in performance outcomes.

Method

This multicentre, randomised controlled pilot study was conducted with eighteen junior doctor volunteers (Foundation and Core Trainee Year 1). Ten were randomly allocated to VR and eight to mannequin-based simulation. Participants completed questionnaires and a 15-minute pneumothorax scenario. Quantitative metrics included overall score, time-to-critical decisions, and academic buoyancy scores (ABS). Qualitative metrics included participants’ likes and dislikes of their allocated simulation modality.

Results

VR participants scored significantly higher than simulation participants in overall scores (74.30% (SD±5.08%) versus 59.75% (SD±10.14) (p=0.04)), and technical skills (77.20% (SD±8.01%) versus 65.00% (SD±8.21%) (p=0.01)). Mannequin-based simulation participants initiated critical decisions faster and demonstrated a trend towards a faster mean time-to-completion (p=0.06). ABS scores increased for both study groups, though was only significant for VR participants (p≤0.01). Participants liked how VR fostered independent learning but disliked the formulaic content and impaired communication-learning compared to mannequin-based simulation.

Conclusion

VR can be as effective as mannequin-based simulation in training junior doctors in acute surgical scenarios. Future research should recruit a larger sample size for a full comparative randomised controlled trial.
O111: SALVAGE: use of SuperficiAL inferior epigastric Vein (SIEV) for superdrainAge in deep inferior epiGastric pErforator (DIEP) flaps
Authors: Shankar Meera
Published: March 2024

Introduction

Deep inferior epigastric perforator (DIEP) flaps are established as the preferred flap for breast reconstruction. Venous congestion is the most common vascular complication that can lead to flap failure and fat necrosis. While limited studies have attempted to assess use of superdrainage using superficial inferior epigastric vein (SIEV) in DIEP flaps, they were inconclusive with small cohort sizes.

Aims

The primary aims of this study were to assess association between use of SIEV in DIEP flaps and reconstructive outcomes based on degree of venous congestion as well as number of graft failures, fat necrotic flaps and post-operative visits. The secondary aims were to analyse the intra-operative time to harvest SIEV and impact of costs to the NHS.

Methodology

2154 patients undergoing DIEP flap reconstruction from March 2010 to June 2022 were restrospectively analyzed. Demographic data, chemo/radiotherapy status, and technique/flap details were procured. Outcome endpoints were evaluated based on occurrence of post-operative venous congestion, total and partial flap loss, fat necrosis, and operative time. Sub-set analysis of demographics was done to assess impact on outcomes.

Results

SIEV use was observed in 216 cases. Total flap loss was observed in 2.31% and partial flap loss in 6.48%. Fat necrosis was observed in 3.24% and post-operative venous congestion in 0.92%. Operative time was observed as 376 ± 48 minutes.

Conclusion

Although there was slightly increased operative time for SIEV harvest, superdrainage considerably reduced venous congestion, flap compromise, and related complications indicating improved overall cost to the NHS.
O174: Designed to respect and repair the aortic arch: An international comparative analysis of RELAY™ Branched endograft outcomes
Authors: Jubouri Matti , Surkhi Abdelaziz , Tan Sven , Bailey Damian , Williams Ian , Piffaretti Gabriele , Bashir Mohamad
Published: March 2024

The introduction of endovascular aortic arch repair (EAR) represents a paradigm shift in the management of complex arch pathologies. In this multicentre original study, a comparative analysis of international outcomes data on the single-, double- and triple-branch RELAY™ endografts is presented. Multicentre data was collected prospectively (2019-2022) and stored in an international registry. This was later retrieved and analysed retrospectively. All patients were followed-up for 24 months. Outcomes measured included target vessel patency (TVP), reintervention, stroke, and mortality. Of the 148 patients, 17 (11.5%) received a single-branch RELAY™, 108 (73%) double-branch, and 23 (15.5%) triple-branch. The group characteristics were similar at baseline. Target vessel cannulation and technical success were achieved in 99.3% of patients. TVP at 30 days post-EAR was 100% in all groups, however, this became 93.8%, 74.0% and 100% at 24 months in the single-, double- and triple-branch endograft groups, respectively. As for reinterventions, these were only required with the double-branch RELAY™ (n=50, 34%). Similarly, disabling strokes were only observed in the double-branch group (n=35, 32.4%), and the overall study incidence was 23.8%. Non-disabling strokes had an overall incidence of 12.8% (n=19). The overall mortality rate was 2.7%, with all 4 deaths recorded occurring in the double-branch group. Logistic regression analysis showed a significant association between urgency (acute) and reintervention. Our results clearly demonstrate that EAR using RELAY™ Branched is a highly efficacious strategy that yields favourable results. Nevertheless, it seems that clinical outcomes with the single- and triple-branch RELAY™ are more optimal than with the double-branch configuration.
O197: Quality Assessment of Human Kidneys by Ex-vivo Normothermic Machine Perfusion prior to Transplantation
Authors: Hosgood Sarah , Wilson Colin , Callaghan Christopher , Phillips Benedict , Bates Lucy , Nicholson Michael
Published: March 2024

Introduction

Ex-vivo normothermic machine perfusion (NMP) is a technique of preservation that can be used to assess the quality and suitability of a kidney for transplantation. This may prevent the unnecessary discard and increase the number of transplanted kidneys.

Methods

A total of 22 kidneys declined for transplant by all UK transplant centres, were assessed over a three-year period across three centres in the UK. Prior to NMP, most kidneys were declined due to poor quality cold flushing at retrieval. All kidneys were assessed during 1h of NMP. A quality assessment score (QAS) based on the appearance, blood flow and urine output was applied to each kidney. Scores ranged from 1 (best) to 5 (worst).

Results

Sixteen kidneys (72%) had a QAS of 1 to 3 and were transplanted into matched recipients. One patient died with a non-functioning kidney 12 days post-transplant due to a cardiac arrest. Six recipients (37.5%) had delayed graft function. The mean serum creatinine levels and estimated glomerular filtration rate at 3 months was 154±74µmol/L and 45±15mL/min/1.73m2, respectively. Graft and patient survival at 12 months were 94%. Of the 6 non-transplanted kidneys, 3 were deemed unsuitable after assessment during NMP, 1 was not transplanted due to logistical reasons and a prolonged cold ischaemic time, and the remaining 2 due to chronic degenerative changes assessed by histology scores.

Conclusion

This clinical research study demonstrated the ability to use NMP technology to successfully increase the number of transplants by assessing kidneys that would otherwise be discarded.