Development of a reliable surgical quality assurance tool for gastrectomy in oncological trials

BACKGROUND

Despite its recognized importance, there is currently no reliable tool for surgical quality assurance (SQA) of gastrectomy in surgical oncology. The aim of this study was to develop an SQA tool for gastrectomy and to apply this tool within the ADDICT Trial in order to assess the extent and completeness of lymphadenectomy.

METHODS

The operative steps for D1+ and D2 gastrectomy have been previously described in the literature and ADDICT trial manual. Two researchers also performed fieldwork in the UK and Japan to document key operative steps through photographs and semi-structured interviews with expert surgeons. This provided the steps that were used as the framework for the SQA tool. Sixty-two photographic cases from the ADDICT Trial were rated by three independent surgeons. Generalizability (G) theory determined inter-rater reliability. D-studies examined the effect of varying the number of assessors and photographic series they rated. Chi-square assessed intra-rater reliability, comparing how the individual assessor's responses corresponded to their global rating for extent of lymphadenectomy.

RESULTS

The tool comprised 20 items, including 19 anatomical landmarks and a global rating score. Overall reliability had G-coefficient of 0.557. Internal consistency was measured with a Cronbach's alpha score of 0.869 and Chi-square confirmed intra-rater reliability for each assessor as < 0.05.

CONCLUSIONS

A photographic surgical quality assurance tool is presented for gastrectomy. Using this tool, the assessor can reliably determine not only the quality but also the extent of the lymphadenectomy performed based on remaining anatomy rather than the excised specimen.

Fecal Bacteria Contamination of Floodwaters and a Coastal Waterway From Tidally-Driven Stormwater Network Inundation

Inundation of coastal stormwater networks by tides is widespread due to sea-level rise (SLR). The water quality risks posed by tidal water rising up through stormwater infrastructure (pipes and catch basins), out onto roadways, and back out to receiving water bodies is poorly understood but may be substantial given that stormwater networks are a known source of fecal contamination. In this study, we (a) documented temporal variation in concentrations of Enterococcus spp. (ENT), the fecal indicator bacteria standard for marine waters, in a coastal waterway over a 2-month period and more intensively during two perigean spring tide periods, (b) measured ENT concentrations in roadway floodwaters during tidal floods, and (c) explained variation in ENT concentrations as a function of tidal inundation, antecedent rainfall, and stormwater infrastructure using a pipe network inundation model and robust linear mixed effect models. We find that ENT concentrations in the receiving waterway vary as a function of tidal stage and antecedent rainfall, but also site-specific characteristics of the stormwater network that drains to the waterway. Tidal variables significantly explain measured ENT variance in the waterway, however, runoff drove higher ENT concentrations in the receiving waterway. Samples of floodwaters on roadways during both perigean spring tide events were limited, but all samples exceeded the threshold for safe public use of recreational waters. These results indicate that inundation of stormwater networks by tides could pose public health hazards in receiving water bodies and on roadways, which will likely be exacerbated in the future due to continued SLR.

Challenges to genetic testing for germline mutations associated with breast cancer among African Americans Authors

Inequities in preventive cancer screening, diagnosis, treatment, and inferior cancer outcomes continue to pose challenges across the cancer continuum. While the exact reasons for these inferior outcomes are unknown, multiple barriers to various domains of social determinants of health (SDOH) play a vital role, leading to inequities in cancer care. These include barriers to transportation, housing, and food insecurities, contributing to delays in preventive screening and treatment. Furthermore, aggressive biologies also exist across various racial profiles with accompanying germline mutations. For example, African Americans (AAs) have a higher incidence of triple-negative breast cancer subtype and a high prevalence of BRCA1/2 gene mutations, increasing the risk of multiple cancers, warranting high-risk screening for these populations. Unfortunately, other barriers, such as financial insecurities, low health literacy rates, and lack of awareness, lead to delays in cancer screening and genetic testing, even with available high-risk screening and risk reduction procedures. In addition, physicians receive minimal interdisciplinary training to address genetic assessment, interpretation of the results, and almost no additional training in addressing the unique needs of racial minorities, leading to suboptimal delivery of genetic assessment provision resources among AAs. In this review, we discuss the confluence of factors and barriers limiting genetic testing among AAs and highlight the prevalence of germline mutations associated with increased risk of breast cancer among AAs, reflecting the need for multi-panel germline testing as well as education regarding hereditary cancer risks in underserved minorities.

Unplanned Hospitalization and Subsequent Mortality in Lung Cancer Patients Undergoing Concomitant Chemo-/Immuno-Therapy and Radiotherapy: An Analysis of Over 10,000 Patients in a Nationwide Database

PURPOSE/OBJECTIVE(S)

Radiotherapy (RT) and concomitant chemotherapy (CHT) is a major modality for treating many malignancies including lung cancer and is associated with toxicity-related unplanned hospitalization (UPH). Previous investigations of factors associated with UPH have been single institutional retrospective studies and none assessed the role of concurrent immunotherapy (IO). Here, we aimed to identify factors associated with UPH and in-hospital mortality by leveraging a multi-institutional nationwide database.

MATERIALS/METHODS

The Vizient® Clinical Data Base which includes data from 98% of the AAMC hospitals and 110 cancer hospitals, was queried for lung cancer patients (any histology) treated in 2019-2021 with RT+CHT/IO. Endpoints were UPH and mortality during or within 30 days of completion of RT. The variables included age, sex, race, ethnicity, income level (quartile), an education level (quartile), any concomitant CHT or IO drugs, RT technique (3D vs. IMRT vs. SBRT), obesity, prior hospitalization within 3 months, prior oncologic surgery within 3 months, prior CHT and/or IO within 3 months, insurance types, hospital types (Rural vs. Urban, AAMC vs. non-AAMC, NCCN vs. non-NCCN, bed size tertile). Logistic regression was performed to identify variables associated with UPH and in-hospital mortality. Data from the Vizient Clinical Data Base used with permission of Vizient, Inc. All rights reserved.

RESULTS

A total of 10,337 patients were included. The rate of UPH and mortality among UPH was 24.5% and 3.2%, respectively. Factors associated with UPH included other races (vs. White, OR 1.44; 95% CI 1.11-1.88; p<0.001), living in a low income zip code (OR 1.7; 95% CI 1.39-2.09; p = 0.0006), living in a zip code with lower education attainment (OR 0.71; 95% CI 0.58-0.86; p = 0.0007), CHT/IO types (cis-etoposide vs. carbo-Taxol, OR 1.33; 95% CI 1.13-1.57; p<0.0001), obesity (OR 1.71; 95% CI 1.53-1.92; p<0.0001), prior hospitalization (OR 2.0; 95% CI 1.80-2.22; p<0.0001), prior oncologic surgery (OR 0.34; 95% CI 0.22-0.52; p<0.0001), other primary payers (vs. commercial; OR 1.75; 95% CI 1.37-2.23; p<0.0001), rural hospital (OR 1.3; 95% CI 1.07-1.62, p<0.01), small bed size (OR 0.59; 95% CI 0.5-0.71; p<0.0001). Factors associated with in-hospital mortality included CHT/IO type (p<0.0001, but cis-etoposide vs. carbo-taxol no difference), prior hospitalization (OR 0.34; 95% CI 0.2-0.56; p<0.0001), AAMC (OR 2.12; 95% CI 1.23-3.67; p = 0.007), bed size (OR 0.58; 95% CI 0.38-0.88; p<0.01).

CONCLUSION

In the largest study to date regarding UPH and in-hospital mortality related to lung RT, we identified factors contributing to these endpoints. Future prospective studies are warranted to develop strategies to prevent these complications in high-risk populations.

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.

Parallel multi-structure decellularisation of a porcine three-dimensional right ventricular outflow tract valved xenograft for use in paediatric congenital cardiac surgery

Funding Acknowledgements

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

Background

Tetralogy of Fallot is the most common cyanotic congenital heart disease and requires right ventricular outflow tract (RVOT) replacement. RVOT substitutes are suboptimal, functionally deteriorating within a few years and necessitating a series of surgical reinterventions. An optimal prosthetic that mimics the structural and mechanical properties of native tissue is desirable. However, due to inadequate homo/autograft availability for neonates and infants, xenografts are commonly used in paediatric cardiac surgery. Current xenografts are limited by lack of growth, susceptibility to calcification, and limited remodelling capacity. Decellularisation to remove immunogenic antigens on the animal-derived tissue reduces the risk of graft rejection. Decellularisation conditions are critical: harsh treatment will disrupt extracellular matrix components vital for in vivo recellularisation; conversely, a too mild treatment may lead to incomplete cell removal and graft degeneration. Decellularisation of valved conduits poses a unique challenge as the valve structure differs significantly to that of the artery. The latter is thicker and stronger, requiring harsher detergents which could damage the valve.

Purpose

This research optimises an in vitro decellularisation protocol for simultaneous removal of porcine cells from the right ventricle (RV), pulmonary artery (PA), and pulmonary valve (PV). We ultimately plan to recellularise the cell-free RVOT scaffold with autologous mesenchymal stem cells via a tissue-engineering approach, endowing the xenograft with growth capacity and improved biocompatibility compared to existing products, thus overcoming the limitations of the currently used replacement grafts.

Methods

The integrated valved RVOT conduits were harvested from pigs and mounted in a temperature-controlled bioreactor chamber. Decellularisation solutions were circulated through the lumen and around the outside of the submerged conduit under constant flow, with extended sodium dodecyl sulfate and nuclease washes. Histological assessment of the RV, PA, and PV by Heamatoxylin and Eosin, for nuclei detection, and Elastin van Gieson’s staining, for elastin and collagen content, report on decellularisation success.

Results

Preliminary results demonstrate effective decellularisation of the RV, PA, and PV in both the valved conduit decellularised immediately after harvesting and following one freeze-thaw cycle. The ability to freeze RVOTs until needed would facilitate production of an accessible surgical product. Images reveal nuclei elimination in each tissue architecture whilst the extracellular matrix composition appears unchanged.

Conclusions

Concurrent multi-tissue decellularisation revealed promising structural results, however mechanical properties of the cell-free RVOT must be assessed to deem decellularisation successful. Further experiments are underway to evaluate the scaffold’s capacity to support mesenchymal stem cell repopulation.

Outcomes from a digital cardiovascular prevention and rehabilitation programme delivered in Ireland during COVID 19

Funding Acknowledgements

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Government of Ireland's Sláintecare Integration Fund Health Research Board, Ireland

Background & Aim

COVID 19 has accelerated the uptake and acceptance of digital health tools for the prevention and management of Cardiovascular Disease. With health systems being urged to learn from the pandemic and to reassess how they will deliver services in future, robust audit and evaluation of digital interventions are required to inform best practice.

This study aims to evaluate the clinical outcomes of a digital CVD prevention and rehabilitation programme which was established during COVID 19 to provide cardiac patients with efficient and timely access to a home-based, structured, comprehensive programme of care.

Methods

Developed and delivered by an interdisciplinary team (Nurse Prescriber, Physiotherapist, Dietitian, Cardiologist), the core components of this 12 week programme included, behavioural change support, lifestyle modification, medical risk factor management and electronic prescribing of cardio-protective medication. To support self-management, patients were provided with a Fitbit, blood pressure monitor and a workbook to support goal setting and overall tracking of progress. Patients were given access to a bespoke web-based platform and invited to attend weekly (2hr) group-based sessions, which included an exercise component and an interactive educational workshop.

Results

Over a 4 month period, 105 patients were referred with an uptake rate of 73% (n=77). Of these, 97% (n=75) enrolled in the programme, with an 85% (n=64) completion rate. Significant improvements in CVD risk factors were observed between initial and end of programme assessment. The proportion of patients meeting guideline-recommended physical activity targets increased from 14 to 82% (p<0.001), mean BMI (kg/m2) reduced from 28.7 to 27.7 (p<0.001), mean Mediterranean diet score improved from 5.2 to 7.3 (p<0.001), and anxiety and depression levels ≥8 (Hospital Anxiety and Depression score) both reduced by more than 50% (p<0.001). The proportions achieving the recommended blood pressure (<130/80 mmHg) and LDL cholesterol targets (<1.4 mmol/L) increased from 24 to 68% (p<0.001) and 14 to 41% (p<0.001), respectively.

Conclusion

Outcomes from this programme demonstrate that digital CVD prevention and rehabilitation programmes can achieve the recommended lifestyle, medical and therapeutic targets associated with reduced CVD events and improved health outcomes. This programme represents a scalable, accessible and effective option to deliver vital CVD preventive care in the patient’s home.

Textbook outcome following oesophagectomy for cancer: international cohort study

Background

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

Methods

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

Results

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

Conclusion

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

Textbook outcome following oesophagectomy for cancer: international cohort study

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSION

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

A256 SURVEILLANCE OF SMALL, NON-FUNCTIONING, ASYMPTOMATIC PANCREATIC NEUROENDOCRINE TUMORS: THE BRITISH COLUMBIA EXPERIENCE

Background

Expert consensus surrounding surveillance for small, non-functioning, asymptomatic pancreatic neuroendocrine tumors (PNETs) remains conflicting. Recent observational studies have shown that surveillance is a safe strategy while large database studies show superior overall survival with surgical resection.

Aims

To describe the growth of small (&lt;2cm), non-functioning, asymptomatic PNETs undergoing surveillance at a tertiary hospital in British Columbia.

Methods

We conducted a retrospective case series of patients with biopsy-proven, non-functioning, asymptomatic PNETs which were &lt;2cm by RECIST criteria at diagnosis, who were followed through active surveillance at Vancouver General Hospital, British Columbia from February 1, 2011-February 1, 2021. Patients were included if serial imaging, whether by endoscopic ultrasound or cross-sectional imaging, was available for a minimum of 24 months.

Results

Of the 57 patients with pathology-proven PNETs that were identified, 14 cases were included after excluding those with resection within 1 year (n=17), lost to follow up (n=13), metastatic disease (n=6), size greater than 2cm at diagnosis (n=4), and with concurrent cancer (n=3). Included patients were predominantly female (n=10, 71%), Caucasian (n=8, 57%), and had a mean Charlson comorbidity index of 3.14. Mean PNET size at diagnosis was 12mm with standard deviation of 4.26mm. Tumors were located in the pancreatic head (n=4, 29%), body (n=6, 42%), and tail (n=4, 29%). Of 8 patients who had Ki67 stains, all were &lt;3%, and of 11 patients with mitotic index, all had &lt;2 mitotic figures. As such, of the 8 patients with available WHO grading, all were grade 1. The average follow-up was 49.6 months with an average tumor growth of 0.82mm per year. When grouping these tumors by growth, 9 (62%) tumors exhibited no growth, 2 tumors grew &lt;1mm per year, 2 tumors grew 1-1.5mm per year, and 1 tumor grew 7.7mm per year. Two cases (14%) of PNETs underwent surgical resection due to size surpassing 2 cm. No patients undergoing surveillance developed metastatic disease.

Conclusions

To our knowledge, we have performed the first Canadian series of small, low-grade PNETS and demonstrated that active surveillance is a safe strategy with most tumors exhibiting no growth of several years. Of the subset of PNETs which demonstrate progression, the preceding surveillance strategy did not disadvantage patients in terms of progression to metastases and allowed for delay of potentially morbid surgery. Further research with prospective studies and larger samples should be conducted.

Funding Agencies

CAG

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.

Management of haematoma after thyroid surgery: systematic review and multidisciplinary consensus guidelines from the Difficult Airway Society, the British Association of Endocrine and Thyroid Surgeons and the British Association of Otorhinolaryngology, Head and Neck Surgery

Haematoma after thyroid surgery can lead to airway obstruction and death. We therefore developed guidelines to improve the safety of peri‐operative care of patients undergoing thyroid surgery. We conducted a systematic review to inform recommendations, with expert consensus used in the absence of high‐quality evidence, and a Delphi study was used to ratify recommendations. We highlight the importance of multidisciplinary team management and make recommendations in key areas including: monitoring; recognition; post‐thyroid surgery emergency box; management of suspected haematoma following thyroid surgery; cognitive aids; post‐haematoma evacuation care; day‐case thyroid surgery; training; consent and pre‐operative communication; postoperative communication; and institutional policies. The guidelines support a multidisciplinary approach to the management of suspected haematoma following thyroid surgery through oxygenation and evaluation; haematoma evacuation; and tracheal intubation. They have been produced with materials to support implementation. While these guidelines are specific to thyroid surgery, the principles may apply to other forms of neck surgery. These guidelines and recommendations provided are the first in this area and it is hoped they will support multidisciplinary team working, improving care and outcomes for patients having thyroid surgery.

Evaluation of a 10-week lifestyle and weight management programme on cardiovascular disease risk factors in a group of people living with obesity referred from a specialist bariatric clinic

Funding Acknowledgements

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Health Service Executive Health and Wellbeing, Saolta University Healthcare Group

OnBehalf

Croí the West of Ireland Cardiac Foundation, Galway, Ireland and the National Institute for Prevention and Cardiovascular Health

Introduction

People living with obesity are at an increased risk of cardiovascular disease (CVD). While development of obesity is multifactorial, lifestyle modification is fundamental to obesity treatment and risk factor reduction. We sought to measure the effects of a structured lifestyle modification programme on the physical and mental health of people living with obesity.

Purpose

This study investigated the impact of a 10-week, community based, lifestyle modification programme on CVD risk factors in people living with obesity (BMI ≥35kg/m2 with a co-morbidity or BMI ≥40kg/m2) who were referred from a specialist bariatric service.

Methods

Delivered by an interdisciplinary team (Nurse, Dietitian & Physiotherapist) the programme included weekly group-based exercise sessions and health promotion workshops. A wide range of topics were addressed in workshops, including nutrition, food labels, emotional eating, physical activity, sedentary behaviour, stress management and CVD risk factor reduction. Outcomes were measured at initial and end of programme assessments.

Results

1122 people participated in the intervention between 2013 and 2019 with 78% (n = 877) completing the programme. At initial assessment 26.7% of participants had a diagnosis of type 2 diabetes; 37.3% were at high or very high risk of CVD; 44.7% were hypertensive and 31.4% had a history of depression. Mean BMI was 47.0kg/m2 with 56.4% of participants having a BMI &gt;45kg/m2. The intervention had significant positive impacts on key outcomes such as psychosocial health, lipid profiles, blood pressure, adiposity and cardiovascular fitness. One of the most significant outcomes observed was the improvement in psycho-social health. Scores of anxiety and depression, assessed using the HADS, decreased by 1.5 and 2.2 points respectively (p &lt;0.001). Mean EQ-VAS score increased by 11 points (p &lt;0.001). There were significant changes in total cholesterol levels with a mean reduction in total cholesterol from 4.69mmol/l to 4.54mmol/l (p &lt;0.001) and LDL cholesterol from 2.79mmol/l to 2.64mmol/l (p &lt;0.001). There were also significant improvements in blood pressure with mean systolic blood pressure reducing by 15.7mmHg (p &lt;0.001) and diastolic blood pressure reducing by 1.4mmHg (p &lt;0.001). For people with type 2 diabetes, there was an increase in those achieving the recommended HbA1c target (&lt;53mmol/l) from 47.6% to 57.4% (p &lt;0.001). Mean reduction in bodyweight was 2.0kg (p &lt;0.001), with 27.2% achieving a weight loss of &gt;3% of initial bodyweight. The percentage of participants achieving the recommended physical activity guidelines increased by 31% (p &lt;0.001).

Conclusions

A lifestyle modification programme delivered by an interdisciplinary team, aimed at individuals living with obesity, is not only acceptable to participants but also significantly reduces CVD risk factors. These findings should influence the design of future programmes and healthcare policies in Ireland and abroad.

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.

Non-ST elevation myocardial infarction; admission to angiogram time at a busy district general hospital

Funding Acknowledgements

Type of funding sources: None.

Background

Cardiovascular disease is the leading cause of morbidity and mortality worldwide. Timely management of acute coronary syndromes, including patients presenting with non-ST elevation myocardial infarction (NSTEMI), is crucial in improving outcomes and reducing mortality. Clinical Guideline 94 (CG94) by National Institute of Health and Care Excellence (NICE) states that patients presenting with a NSTEMI with an intermediate or higher risk score should be offered coronary angiography within 96 hours of admission to hospital.

Purpose

The purpose of this audit is to assess how well our General Hospital adhered to the recommended NSTEMI intervention set by the NICE guidelines.

Methods

Data was collected between September and December 2019 for patients admitted with an NSTEMI to the cardiology department at our General Hospital. Data was analysed using in-patient paper notes and Microsoft Excel.

Results

Of the 54 patients admitted with NSTEMI, 67% met the NICE guideline for angiogram within 96 hours of admission. The most common reason for delay was infection or raised inflammatory markers (28%). Other medical reasons include pulmonary oedema (11.1%), acute kidney injury (11.1%) and stroke (11.1%). Another notable reason for delay to angiogram was weekend admissions and wait for cardiology bed (22.2%). Six-month mortality rates showed that, 75% of deceased patients did not undergo an angiogram within 96 hours of admission.

Conclusion

We have an elderly population with multiple co-morbidities. Therefore, whilst patients are being managed for other acute medical problems they are deemed unfit for an immediate angiogram ultimately causing a delay. Furthermore, some patients were not referred to cardiology immediately after the NSTEMI event which causes delay in organising the angiogram. Finally, some patients were awaiting a cardiology bed in the Acute Admissions Unit. This causes delay as patients cannot undergo angiogram without a cardiology bed available for recovery. These delays are causing significant differences in the mortality rates of NSTEMI patients.

In order to address these issues, a hospital guideline for junior doctors regarding the management of NSTEMIs has been designed and distributed. The guideline emphasises the importance of early cardiology referral, the management of acute medical problems in NSTEMIs such pre-hydration to prevent acute kidney injury, and the medical management of NSTEMIs in line with the 2020 ESC guidelines. Finally, it would be useful to re-audit these findings to assess if mortality rates and adherence to the NICE and ESC guidelines improve following these interventions.

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.

896 Improving Intravenous Fluid Therapy to Reduce the Incidence of Acute Kidney Injury in Hip Fracture Patients

Background

Acute kidney injury (AKI) in hip fracture patients is associated with morbidity, mortality, and increased length of stay. To avoid this our unit policy recommends maintenance crystalloid IV fluids of &gt; 62.5mL/Hr for hip fracture patients.

Method

Three prospective audits, each including 100 consecutive acute hip fracture patients, were completed with interventional measures employed between each cycle. Data collection points included details of IV fluid administration and pre/post-operative presence of AKI. Interventions between cycles included implementation of admission/post-take checklist tools and various educational measures for Emergency Department, nursing and admitting team staff with dissemination of infographic posters, respectively.

Results

In cycle one and two, many patients received inadequate fluids (46/100 and 56/100 respectively). There was no significant difference in the incidence of AKI between patients receiving adequate or inadequate fluid in either cycle (p &lt; 0.05).

In cycle three, more patients received adequate fluids (79/100, p &lt; 0.05). Patients prescribed adequate fluids were less likely to develop post-operative AKI (2/79, 2.5% vs 3/21, 14.3%; p &lt; 0.05).

Discussion

This audit demonstrates the importance of administering appropriate IV fluid in hip fracture patients to avoid AKI. Improving coordination with Emergency Department and ward nursing/medical ward staff was a critical step in improving our unit’s adherence to policy.

Honouring COVID-19 restrictions: A qualitative study of the virtual asd diagnostic pathway in a uk nhs camhs service

Introduction

The Multi-Agency Autism Team (MAAT) diagnose Autism Spectrum Disorder (ASD) in children and young people using a multi-stage assessment process. In March 2020, the UK went into lockdown due to the COVID-19 pandemic, affecting the MAAT’s ability to continue their typical diagnostic pathway.

Objectives

This qualitative study aimed to assess the effectiveness and feasibility of a virtual ASD diagnostic pathway.

Methods

From March – September; one hundred detailed developmental history assessments were conducted over the telephone, fifteen socially-distanced BOSA (Brief Observation of Symptoms of Autism) assessments were piloted, twenty-five multi-disciplinary formulation meeting were held over a video platform, and sixty diagnosis feedback consultations were conducted via telephone or video call. Structured interviews were conducted with clinicians and service-users.

Results

revealed that telephone developmental history assessments were generally preferable over face-to-face appointments, and video-based formulation meetings were effective, productive and resulted in higher clinician attendance. The qualitative data on feedback appointments was mixed. Clinicians felt that telephone appointments were less personable and ethical; whereas, video-based feedback appointments allowed for more empathy. However, the majority of service-users opted for tele-calls over video-calls for these appointments. Socially-distanced BOSAs obtained positive clinician feedback in general. Service-user feedback was mixed; some found the experience uncomfortable and unfamiliar, whilst others enjoyed the experience. Overall, service-users were content with the knowledge that it may support a diagnostic outcome for their child.

Conclusions

We concluded that the overall experience of the virtual ASD diagnostic pathway was a positive and informative process, identifying opportunities for permanent change to the service.

113 Improving Intravenous Fluid Therapy to Reduce the Incidence of Acute Kidney Injury in Elderly Hip Fracture Patients

Background

Acute kidney injury (AKI) in hip fracture patients is associated with morbidity, mortality, and increased length of stay. To avoid this our unit policy recommends maintenance crystalloid IV fluids of &gt;62.5 mL/Hr for hip fracture patients. However, audits have shown that many patients still receive inadequate IV fluids.

Methods

Three prospective audits, each including 100 consecutive acute hip fracture patients aged &gt;55, were completed with interventional measures employed between each cycle. Data collection points included details of IV fluid administration and pre/post-operative presence of AKI. Interventions between cycles included a revised checklist for admissions with a structured ward round tool for post-take ward round and various educational measures for Emergency Department, nursing and admitting team staff with dissemination of infographic posters, respectively.

Results

Cycle 1: 64/100 (64%) patients received adequate fluids. No significant difference in developing AKI post operatively was seen in patients given adequate fluids (2/64, 3.1%) compared to inadequate fluids (4/36, 11.1%; p = 0.107). More patients with pre-operative AKI demonstrated resolution of AKI with appropriate fluid prescription (5/6, 83.3%, vs 0/4, 0%, p &lt; 0.05) Cycle 2: Fewer patients were prescribed adequate fluids (54/100, 54%). There was no significant difference in terms of developing AKI post operatively between patients with adequate fluids (4/54, 7.4%) or inadequate fluids (2/46, 4.3%; p = 0.52). Resolution of pre-operative AKI was similar in patients with adequate or inadequate fluid administration (4/6, 67% vs 2/2, 100%). Cycle 3: More patients received adequate fluids (79/100, 79%, p &lt; 0.05). Patients prescribed adequate fluids were less likely to develop post-operative AKI than those receiving inadequate fluids (2/79, 2.5% vs 3/21, 14.3%; p &lt; 0.05).

Discussion

This audit demonstrates the importance of administering appropriate IV fluid in hip fracture patients to avoid AKI. Improving coordination with Emergency Department and ward nursing/medical ward staff was a critical step in improving our unit’s adherence to policy.

Perioperative intravenous contrast administration and the incidence of acute kidney injury after major gastrointestinal surgery: prospective, multicentre cohort study

BACKGROUND

This study aimed to determine the impact of preoperative exposure to intravenous contrast for CT and the risk of developing postoperative acute kidney injury (AKI) in patients undergoing major gastrointestinal surgery.

METHODS

This prospective, multicentre cohort study included adults undergoing gastrointestinal resection, stoma reversal or liver resection. Both elective and emergency procedures were included. Preoperative exposure to intravenous contrast was defined as exposure to contrast administered for the purposes of CT up to 7 days before surgery. The primary endpoint was the rate of AKI within 7 days. Propensity score-matched models were adjusted for patient, disease and operative variables. In a sensitivity analysis, a propensity score-matched model explored the association between preoperative exposure to contrast and AKI in the first 48 h after surgery.

RESULTS

A total of 5378 patients were included across 173 centres. Overall, 1249 patients (23·2 per cent) received intravenous contrast. The overall rate of AKI within 7 days of surgery was 13·4 per cent (718 of 5378). In the propensity score-matched model, preoperative exposure to contrast was not associated with AKI within 7 days (odds ratio (OR) 0·95, 95 per cent c.i. 0·73 to 1·21; P = 0·669). The sensitivity analysis showed no association between preoperative contrast administration and AKI within 48 h after operation (OR 1·09, 0·84 to 1·41; P = 0·498).

CONCLUSION

There was no association between preoperative intravenous contrast administered for CT up to 7 days before surgery and postoperative AKI. Risk of contrast-induced nephropathy should not be used as a reason to avoid contrast-enhanced CT.

132 Introduction of F508del human mutation into the CFTR gene of sheep fetal fibroblasts using CRISPR/Cas9 ribonucleoprotein

Cystic fibrosis (CF) is an autosomal recessive genetic disease that affects over 30 000 people in the United States and is caused by mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene. The CFTR protein is a cAMP-regulated C− channel responsible for regulation of anion transport, primarily in the epithelial cells. We have previously generated a sheep model of CF by genetically inactivating the CFTR gene (Fan et al. 2018 JCI Insight 3, e123529). The newborn CFTR −/− sheep develops severe disease consistent with CF pathology in humans. The CF model is extremely valuable for understanding the developmental aspects of CF disease, as sheep have been used extensively in the study of human fetal growth and development. Sheep, like humans, typically give birth to only one or two offspring in each pregnancy, which make them more suitable than many other species for testing prenatal gene-editing treatments. Thus, in this new study, we are working on the generation of F508del sheep CF model. The F508del mutation was chosen because it is the most common mutation in the human CFTR gene (~70%). This mutation is characterised by the deletion of the CTT nucleotides, which ultimately deletes the phenylalanine residue at position 508. The F508del mutation causes misfolding of the CFTR protein, which is further degraded by proteases. Even though several CFTR modulators are available, they are not effective in all patients. Additionally, they cannot reverse deleterious prenatal CF manifestations. Hence, this model will be valuable for evaluating both prenatal drug and gene therapies. Here, we used a CRISPR/Cas9 gene-editing approach to introduce the F508del mutation into the sheep genome. We designed an sgRNA targeting exon 11 of the sheep CFTR gene using the Benchling software (https://benchling.com/academic). The sgRNA was synthesised by Synthego and Cas9 purchased from ThermoFisher. Using the Lonza-4D-Nucleofector system, Cas9/sgRNA ribonucleoprotein complex was transfected into sheep fetal fibroblasts (SFFs), along with 100bp single-stranded oligodeoxynucleotide, flanking the F508del mutation, for the homology-directed repair. The transfected cells were subsequently cultured in Dulbecco's modified Eagle's medium, supplemented with 15% fetal bovine serum and 1% penicillin, and incubated at 38.5°C. Two days post-transfection, SFFs were seeded individually into five 96-well plates by limited dilution. After seven days, the individual colonies were expanded into 24-well plates and cultured for three more days. A total of 56 single-cell-derived SFF colonies were isolated. The presence of F508del mutation was confirmed by amplifying the PCR products of the exon 11 flanking the mutation site and subjecting each amplicon to Sanger sequencing. The sequencing results indicated that the indels (insertion/deletion) were introduced in 49 out of 56 (87.5%) of the colonies, and four (7.14%) of them were confirmed to have biallelic F508del mutations based on sequencing peaks. Therefore, we successfully introduced the F508del mutation in SFFs that will be used for the production of F508del CF sheep by somatic cell nuclear transfer.

Human model of burn injury that quantifies the benefit of cooling as a first aid measure

BACKGROUND

Burn injuries are a major cause of morbidity and mortality worldwide. Cooling is widely practised as a first aid measure, but the efficacy of cooling burns in human skin has not been demonstrated. A safe, consistent, ethically acceptable model of burning and cooling in live human skin in vivo was developed, and used to quantify the effects of cooling.

METHODS

Novel apparatus was manufactured to create and cool burns in women who were anaesthetized for breast reconstruction surgery using a deep inferior epigastric artery perforator flap. Burns were excised between 1 and 3 h after creation, and analysed using histopathological assessment.

RESULTS

All 25 women who were approached agreed to take part in the study. There were no adverse events. Increased duration of contact led to increased burn depth, with a contact time of 7·5 s at 70°C leading to a mid-dermal burn. Burn depth progressed over time following injury, but importantly this was modified by cooling the burn at 16°C for 20 min. On average, cooling salvaged 25·2 per cent of the dermal thickness.

CONCLUSION

This study demonstrated the favourable effects of cooling on human burns. Public heath messaging should emphasize cooling as first aid for burns. This model will allow analysis of the molecular effects of cooling burns, and provide a platform for testing novel therapies aimed at reducing the impact of burn injury.

TNF-derived peptides inhibit tumour growth and metastasis through cytolytic effects on tumour lymphatics

Tumour necrosis factor (TNF) is a multi-functional cytokine with profound and diverse effects on physiology and pathology. Identifying the molecular determinants underlying the functions and pathogenic effects of TNF is key to understanding its mechanisms of action and identifying new therapeutic opportunities based on this important molecule. Previously, we showed that some evolutionarily conserved peptides derived from TNF could induce cell death (e.g. apoptosis and/or necrosis), a feature of immune defence mechanisms shared by many vertebrates. In this study, we demonstrated that necrosis-inducing peptide P16 kills human glioblastoma cancer cells and primary human hepatoma or renal cancer cells isolated from patients who had not responded to standard treatments. Importantly, we show that the necrosis-inducing peptide P1516 significantly improves survival by inhibiting tumour metastasis in a 4T1 breast cancer syngeneic graft mouse model. Because the lymphatic system is an important metastatic route in many cancers, we also tested the effect of TNF-derived peptides on monolayers of primary human lymphatic endothelial cells (hDLEC) and found that they increased junctional permeability by inducing cytoskeletal reorganization, gap junction formation and cell death. Transmission electron microscopy imaging evidence, structural analysis and in-vitro liposome leakage experiments strongly suggest that this killing is due to the cytolytic nature of these peptides. P1516 provides another example of a pro-cytotoxic TNF peptide that probably functions as a cryptic necrotic factor released by TNF degradation. Its ability to inhibit tumour metastasis and improve survival may form the basis of a novel approach to cancer therapy.

Transcriptional networks in the human epididymis

BACKGROUND

The epithelial lining of the human epididymis is critical for sperm maturation. This process requires distinct specialized functions in the head, body, and tail of the duct. These region-specific properties are maintained by distinct gene expression profiles which are governed by transcription factor networks, non-coding RNAs, and other factors.

MATERIALS AND METHODS

We used genome-wide protocols including DNase-seq, RNA-seq and ChIP-seq to characterize open (active) chromatin, the transcriptome and occupancy of specific transcription factors (TFs) respectively, in caput, corpus, and cauda segments of adult human epididymis tissue and primary human epididymis epithelial (HEE) cell cultures derived from them. RNA-seq following TF depletion or activation, combined with gene ontology analysis also determined TF targets.

RESULTS

Among regional differentially expressed transcripts were epithelial-selective transcription factors (TFs), microRNAs, and antiviral response genes. Caput-enriched TFs included hepatocyte nuclear factor 1 (HNF1) and the androgen receptor (AR), both of which were also predicted to occupy cis-regulatory elements identified as open chromatin in HEE cells. HNF1 targets were identified genome-wide using ChIP-seq, in HEE cells. Next, siRNA-mediated depletion of HNF1 revealed a pivotal role for this TF in coordinating epithelial water and solute transport in caput epithelium. The importance of AR in HEE cells was shown by AR ChIP-seq, and by RNA-seq after synthetic androgen (R1881) treatment. AR has a distinct transcriptional program in the HEE cells and likely recruits different co-factors (RUNX1 and CEBPβ) in comparison to those used in prostate epithelium.

DISCUSSION AND CONCLUSION

Our data identify many transcription factors that regulate the development and differentiation of HEE cells. Moreover, a comparison between immature and adult HEE cells showed key TFs in the transition to fully differentiated function of this epithelium. These data may help identify new targets to treat male infertility and have the potential to open new avenues for male contraception.

Abstract GS5-05: Resistance to neoadjuvant chemotherapy in triple negative breast cancer mediated by a reversible drug-tolerant state

Approximately 50% of patients with localized triple negative breast cancer (TNBC) have substantial residual cancer burden following treatment with neoadjuvant chemotherapy (NACT), resulting in distant metastasis and death for most of these patients. While genomic and phenotypic intra-tumor heterogeneity are pervasive features of TNBCs at the time of diagnosis, the functional contributions of heterogeneous tumor cell populations to chemoresistance have not been elucidated.

To investigate tumor evolution accompanying NACT, we employed orthotopic patient-derived xenograft (PDX) models of treatment-naïve TNBC, which retain intra-tumor heterogeneity characteristic of human TNBC. We discovered that some PDX models initially exhibited partial sensitivity to standard front-line NACT (Adriamycin plus Cytoxan, AC). Following AC, residual tumors were resistant to chemotherapy but repopulated tumors with chemo-sensitive cells if left untreated, indicating that tumor cells possessed inherent plasticity. To identify the tumor cell subpopulation(s) conferring chemoresistance, we conducted barcode-mediated clonal tracking in three independent PDX models by introducing a high-complexity pooled lentiviral barcode library into PDX tumor cells which were then orthotopically engrafted into recipient mice. Strikingly, residual tumors maintained the same heterogeneous clonal architecture as naïve tumors. Concordantly, whole-exome sequencing revealed conservation of genomic subclonal architecture throughout treatment. These results were corroborated by genomic sequencing of serial biopsies pre- and post-AC obtained directly from TNBC patients enrolled on an ongoing clinical trial at MD Anderson (ARTEMIS; NCT02276443). Together, these studies revealed that genomically distinct pre-treatment subclones were equally capable of surviving AC to reconstitute tumors after treatment.

To identify functional addictions of residual tumor cells, we conducted histologic and transcriptomic profiling. Residual tumors following AC-treatment exhibited extensive fibrotic desmoplasia and tumor cell pleomorphism in both PDX models and in serial biopsies obtained from TNBC patients enrolled on the ARTEMIS trial. Strikingly, these AC-induced features were reverted upon regrowth of residual tumors in PDXs and in patients' tumors. Similarly, residual tumors exhibited unique transcriptomic features, many of which are also de-regulated in cohorts of human TNBCs undergoing chemotherapy treatment. These features were nearly completely reverted after tumors regrew, suggesting that the residual tumor state may be a unique and transient therapeutic window. Gene set enrichment analyses revealed that residual tumors had increased activation of oxidative phosphorylation and decreased glycolytic signaling. Pharmacologic targeting of oxidative phosphorylation with a small-molecule inhibitor of mitochondrial electron transport chain complex I (IACS-010759) significantly delayed the regrowth of AC-treated residual tumors in three independent PDX models. Collectively, these studies reveal that a reversible phenotypic state can confer chemoresistance in the absence of genomic selection and that the residual tumor state is a novel therapeutic window for chemo-refractory TNBC.

Citation Format: Echeverria GV, Ge Z, Seth S, Jeter-Jones SL, Zhang X, Zhou X, Cai S, Tu Y, McCoy A, Peoples M, Lau R, Shao J, Sun Y, Bristow C, Carugo A, Ma X, Harris A, Wu Y, Moulder S, Symmans WF, Marszalek JR, Heffernan TP, Chang JT, Piwnica-Worms H. Resistance to neoadjuvant chemotherapy in triple negative breast cancer mediated by a reversible drug-tolerant state [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr GS5-05.

Identical and Nonidentical Twins: Risk and Factors Involved in Development of Islet Autoimmunity and Type 1 Diabetes

OBJECTIVE

There are variable reports of risk of concordance for progression to islet autoantibodies and type 1 diabetes in identical twins after one twin is diagnosed. We examined development of positive autoantibodies and type 1 diabetes and the effects of genetic factors and common environment on autoantibody positivity in identical twins, nonidentical twins, and full siblings.

RESEARCH DESIGN AND METHODS

Subjects from the TrialNet Pathway to Prevention Study (N = 48,026) were screened from 2004 to 2015 for islet autoantibodies (GAD antibody [GADA], insulinoma-associated antigen 2 [IA-2A], and autoantibodies against insulin [IAA]). Of these subjects, 17,226 (157 identical twins, 283 nonidentical twins, and 16,786 full siblings) were followed for autoantibody positivity or type 1 diabetes for a median of 2.1 years.

RESULTS

At screening, identical twins were more likely to have positive GADA, IA-2A, and IAA than nonidentical twins or full siblings (all P < 0.0001). Younger age, male sex, and genetic factors were significant factors for expression of IA-2A, IAA, one or more positive autoantibodies, and two or more positive autoantibodies (all P ≤ 0.03). Initially autoantibody-positive identical twins had a 69% risk of diabetes by 3 years compared with 1.5% for initially autoantibody-negative identical twins. In nonidentical twins, type 1 diabetes risk by 3 years was 72% for initially multiple autoantibody-positive, 13% for single autoantibody-positive, and 0% for initially autoantibody-negative nonidentical twins. Full siblings had a 3-year type 1 diabetes risk of 47% for multiple autoantibody-positive, 12% for single autoantibody-positive, and 0.5% for initially autoantibody-negative subjects.

CONCLUSIONS

Risk of type 1 diabetes at 3 years is high for initially multiple and single autoantibody-positive identical twins and multiple autoantibody-positive nonidentical twins. Genetic predisposition, age, and male sex are significant risk factors for development of positive autoantibodies in twins.

The role of hardiness in the bullying-mental health relationship

Background

Workplace bullying has consistently been found to predict mental health problems among those affected. However, less attention has been given to personal dispositions as possible moderators in this relationship.

Aims

To investigate the moderating role of individual hardiness in the relationship between exposure to bullying behaviours and symptoms of anxiety and depression, respectively, assuming that high hardiness, being an individual stress resilience factor, acts as a buffer in these relationships.

Methods

Survey data were gathered in 2016-17, among land-based employees in a Norwegian oil and gas company. Participants completed a questionnaire electronically via a link sent to their work e-mail. The PROCESS macro SPSS supplement was used to analyse the proposed relationships, with mean-centred variables.

Results

Altogether, 275 participated in the study (46% response rate). High hardiness acted as a buffer in the bullying-anxiety relationship, in that hardy individuals did not experience increased levels of anxiety when facing bullying behaviours. Low levels of hardiness, on the other hand, acted as an enhancement factor, in that the bullying-anxiety relationship was strengthened for this group. Contrary to expectations, hardiness did not act as a buffer in the bullying-depression relationship.

Conclusions

Hardy individuals were less likely to report anxiety in response to bullying than non-hardy workers, a finding with important practical implications. Yet, regardless of who is affected, managers should focus on good strategies to intervene when bullying is detected, and stress resilience training should be considered as part of these strategies.

205 Towards the correction of meconium ileus with cystic fibrosis transmembrane conductance regulator (CFTR) intestinal expression in CFTR knockout sheep

Cystic fibrosis (CF) is a human autosomal genetic disease caused by mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene, which is responsible for Cl − anion transport in epithelial cells. We previously generated CFTR +/− and CFTR −/− lambs using CRISPR/Cas9 and somatic cell nuclear transfer (SCNT) techniques. The CFTR −/− lambs display many features similar to humans with CF, including meconium ileus (MI), pancreatic fibrosis, portal fibrosis and biliary hyperplasia, small gallbladder, and absence of the vas deferens. Although MI affects only 15 to 20% of human babies with CF, it was observed in 100% of newborn CFTR −/− lambs and was the primary cause of death. We here hypothesized that the transgenic expression of ovine CFTR cDNA under regulation of the rat intestinal fatty acid binding protein (iFABP) promoter would promote the correction of MI in CFTR −/− sheep. In this study, we constructed the pcDNA3.1&gt;iFABP&gt;CFTR expression vector in order to generate iFABP&gt;CFTR transgenic CFTR −/− sheep. PCR and sequence analysis of all junction regions confirmed the presence of the inserts in the vector. We transfected male and female CFTR −/− sheep fetal fibroblasts with the construct. Three days after transfection, limiting dilution and G418 selection were used for the isolation of resistant single cell derived colonies. A total of 15 male colonies containing the pcDNA3.1&gt;iFABP&gt;CFTR vector was confirmed by PCR and sequence analysis. Three male cell colonies were used as nuclear donors for SCNT. In total, 129 one-cell-stage cloned embryos were generated and transferred into 11 estrus-synchronized recipients. Four recipients (4/11; 36.3%) were confirmed pregnant at Day 40 to 45 of gestation. One pregnancy went to term and resulted in the birth of a single lamb. The necropsy indicated the same abnormalities, including MI, seen in CFTR −/− lambs. A PCR assay confirmed the presence of the iFABP&gt;CFTR transgene in the genome of the cloned offspring. The lack of MI correction is likely due to the low expression of CFTR in this particular colony. Western blot analysis is in progress. Additional embryo transfers will be performed using different single-cell-derived colonies.

A GIS APPROACH TO IDENTIFYING SERVICE ACCESS DISPARITIES IN RURAL APPALACHIA

Formal service use can help decrease caregiving burden for family members of persons with dementia; however, barriers related to service use are common. For example, driving distance can be problematic in rural areas with mountainous terrain, as in the Appalachian region of Virginia. The purpose of this study was to examine distance from family homes to services and its association with service use. Thirty-nine caregivers’ residences and 84 service locations were mapped, then driving distance to and distribution of services were analyzed using Service Area Solver and Closest Facility Solver in ArcGIS. Results suggest that services were unevenly distributed based on caregiver location. Specifically, of all services examined, food banks and medical facilities had the most facilities near caregiver locations, whereas adult day services, support groups, and educational programs for caregivers were sparse. Findings are discussed in light of identifying vulnerable caregivers as well as hot-spots for potential interventions.

Life on a knife edge: using simulation to engage young people in issues surrounding knife crime

BACKGROUND

Knife-related behaviour among young people is an increasing social concern with a total of 35 teenagers killed by knife attacks in England in 2017. Distributed simulation has been shown to be a valid method of portable simulation for medical professionals; however, its role in delivering a socially educational message to members of the public has not been previously studied. This paper explores how the novel use of simulation could be used to address a serious social issue amongst young people at risk of criminal knife behaviour.

METHODS

A qualitative approach was used to study a two-part workshop attended by two groups of young people vulnerable to knife crime. Based on the concepts of sequential simulation and distributed simulation previously developed at the Imperial College Centre for Engagement and Simulation Science, the first part of the workshop showed the patient journey of a young man stabbed in the abdomen, attended by policemen and paramedics, followed by the participants witnessing a simulated emergency abdominal operation on a silicone model and concluded with a dialogue between the surgeon, the victim (who required an intestinal stoma as a result of the knife injury) and his mother. The second part of the workshop involved further discussion with the participants regarding the role of knives from the personal and community perspective. Visual data was recorded during the workshops and qualitative data obtained from group and individual interviews were thematically analysed.

RESULTS

A total of sixty teenagers aged 13-19 took part in the two workshops. The participant feedback suggested that the workshops provided a safe environment where young people could learn about and explore the consequences surrounding knife crime. Furthermore, participant recollection of key points was assessed between 4 and 6 weeks after the second workshop and the data suggested that the workshop could promote learning and a change in the participants' knife-related behaviour in the future.

CONCLUSIONS

The findings support further exploration of simulation as a modality for engaging young people about the issues surrounding criminal knife behaviour in a safe and cooperative environment. Moreover, the findings suggest that the workshop could be used as an educational tool that may facilitate behavioural change.