New robotic platform for transoral robotic surgery: an IDEAL stage 0 study

Objectives

This study aims to assess the feasibility to perform transoral robotic surgery (TORS) with a new robotic platform, the Versius Surgical System (CMR Surgical, UK) in a preclinical cadaveric setting in accordance to stage 0 of the IDEAL-D framework.

Design

IDEAL stage 0 preclinical assessment of the Versius Robotic System in TORS in human cadavers.

Setting

All procedures were performed in a simulated operating theatre environment at a UK surgical training centre.

Participants

11 consultant head and neck surgeons from the UK, mainland Europe and the USA took part in TORS procedures on six human cadavers.

Interventions

3 key index procedures were assessed that represent the core surgical workload of TORS: lateral oropharyngectomy, tongue base resection and partial supraglottic laryngectomy.

Main outcome measures

The primary outcome was the successful completion of each surgical procedure. Secondary outcomes included the optimisation of system setup, instrumentation and surgeon-reported outcomes for feasibility of each component procedural step.

Results

33 cadaveric procedures were performed and 32 were successfully completed. One supraglottic laryngectomy was not fully completed due to issues dividing the epiglottic cartilage with available instrumentation. Surgeon-reported outcomes met the minimal level of feasibility in all procedures and a consensus that it is feasible to perform TORS with Versius was reached. Available instrumentation was not representative of other robotic platforms used in TORS and further instrument optimisation is recommended before wider dissemination.

Conclusions

It is feasible to perform TORS with the Versius Surgical System (CMR Surgical) within a pre-clinical cadaveric setting. Clinical evaluation is needed and appropriate with the system. Further instrument development and optimisation is desirable.

Identification and targeting of treatment resistant progenitor populations in T-cell Acute Lymphoblastic Leukemia

Refractoriness to initial chemotherapy and relapse after remission are the main obstacles to cure in T-cell Acute Lymphoblastic Leukemia (T-ALL). Biomarker guided risk stratification and targeted therapy have the potential to improve outcomes in high-risk T-ALL; however, cellular and genetic factors contributing to treatment resistance remain unknown. Previous bulk genomic studies in T-ALL have implicated tumor heterogeneity as an unexplored mechanism for treatment failure. To link tumor subpopulations with clinical outcome, we created an atlas of healthy pediatric hematopoiesis and applied single-cell multiomic (CITE-seq/snATAC-seq) analysis to a cohort of 40 cases of T-ALL treated on the Children's Oncology Group AALL0434 clinical trial. The cohort was carefully selected to capture the immunophenotypic diversity of T-ALL, with early T-cell precursor (ETP) and Near/Non-ETP subtypes represented, as well as enriched with both relapsed and treatment refractory cases. Integrated analyses of T-ALL blasts and normal T-cell precursors identified a bone-marrow progenitor-like (BMP-like) leukemia sub-population associated with treatment failure and poor overall survival. The single-cell-derived molecular signature of BMP-like blasts predicted poor outcome across multiple subtypes of T-ALL within two independent patient cohorts using bulk RNA-sequencing data from over 1300 patients. We defined the mutational landscape of BMP-like T-ALL, finding that NOTCH1 mutations additively drive T-ALL blasts away from the BMP-like state. We transcriptionally matched BMP-like blasts to early thymic seeding progenitors that have low NR3C1 expression and high stem cell gene expression, corresponding to a corticosteroid and conventional cytotoxic resistant phenotype we observed in ex vivo drug screening. To identify novel targets for BMP-like blasts, we performed in silico and in vitro drug screening against the BMP-like signature and prioritized BMP-like overexpressed cell-surface (CD44, ITGA4, LGALS1) and intracellular proteins (BCL-2, MCL-1, BTK, NF-κB) as candidates for precision targeted therapy. We established patient derived xenograft models of BMP-high and BMP-low leukemias, which revealed vulnerability of BMP-like blasts to apoptosis-inducing agents, TEC-kinase inhibitors, and proteasome inhibitors. Our study establishes the first multi-omic signatures for rapid risk-stratification and targeted treatment of high-risk T-ALL.

The impact of signposting and group support pathways on a community-based physical activity intervention grounded in motivational interviewing

BACKGROUND

Brief advice is recommended to increase physical activity (PA) within primary care. This study assessed change in PA levels and mental well-being after a motivational interviewing (MI) community-based PA intervention and the impact of signposting (SP) and social action (SA) (i.e. weekly group support) pathways.

METHODS

Participants (n = 2084) took part in a community-based, primary care PA programme using MI techniques. Self-reported PA and mental well-being data were collected at baseline (following an initial 30-min MI appointment), 12 weeks, 6 months and 12 months. Participants were assigned based upon the surgery they attended to the SP or SA pathway. Multilevel models derived point estimates and 95% confidence intervals for outcomes at each time point and change scores.

RESULTS

Participants increased PA and mental well-being at each follow-up time point through both participant pathways and with little difference between pathways. Retention was similar between pathways at 12 weeks, but the SP pathway retained more participants at 6 and 12 months.

CONCLUSIONS

Both pathways produced similar improvements in PA and mental well-being; however, the addition of a control would have provided further insight as to the effectiveness. Due to lower resources yet similar effects, the SP pathway could be incorporated to support PA in primary care settings.

The impact of signposting and group support pathways on a community-based physical activity intervention grounded in motivational interviewing

BACKGROUND

Brief advice is recommended to increase physical activity (PA) within primary care. This study assessed change in PA levels and mental well-being after a motivational interviewing (MI) community-based PA intervention and the impact of signposting (SP) and social action (SA) (i.e. weekly group support) pathways.

METHODS

Participants (n = 2084) took part in a community-based, primary care PA programme using MI techniques. Self-reported PA and mental well-being data were collected at baseline (following an initial 30-min MI appointment), 12 weeks, 6 months and 12 months. Participants were assigned based upon the surgery they attended to the SP or SA pathway. Multilevel models derived point estimates and 95% confidence intervals for outcomes at each time point and change scores.

RESULTS

Participants increased PA and mental well-being at each follow-up time point through both participant pathways and with little difference between pathways. Retention was similar between pathways at 12 weeks, but the SP pathway retained more participants at 6 and 12 months.

CONCLUSIONS

Both pathways produced similar improvements in PA and mental well-being; however, the addition of a control would have provided further insight as to the effectiveness. Due to lower resources yet similar effects, the SP pathway could be incorporated to support PA in primary care settings.

Standards of Care for the Health of Transgender and Gender Diverse People, Version 8

Background: Transgender healthcare is a rapidly evolving interdisciplinary field. In the last decade, there has been an unprecedented increase in the number and visibility of transgender and gender diverse (TGD) people seeking support and gender-affirming medical treatment in parallel with a significant rise in the scientific literature in this area. The World Professional Association for Transgender Health (WPATH) is an international, multidisciplinary, professional association whose mission is to promote evidence-based care, education, research, public policy, and respect in transgender health. One of the main functions of WPATH is to promote the highest standards of health care for TGD people through the Standards of Care (SOC). The SOC was initially developed in 1979 and the last version (SOC-7) was published in 2012. In view of the increasing scientific evidence, WPATH commissioned a new version of the Standards of Care, the SOC-8. Aim: The overall goal of SOC-8 is to provide health care professionals (HCPs) with clinical guidance to assist TGD people in accessing safe and effective pathways to achieving lasting personal comfort with their gendered selves with the aim of optimizing their overall physical health, psychological well-being, and self-fulfillment. Methods: The SOC-8 is based on the best available science and expert professional consensus in transgender health. International professionals and stakeholders were selected to serve on the SOC-8 committee. Recommendation statements were developed based on data derived from independent systematic literature reviews, where available, background reviews and expert opinions. Grading of recommendations was based on the available evidence supporting interventions, a discussion of risks and harms, as well as the feasibility and acceptability within different contexts and country settings. Results: A total of 18 chapters were developed as part of the SOC-8. They contain recommendations for health care professionals who provide care and treatment for TGD people. Each of the recommendations is followed by explanatory text with relevant references. General areas related to transgender health are covered in the chapters Terminology, Global Applicability, Population Estimates, and Education. The chapters developed for the diverse population of TGD people include Assessment of Adults, Adolescents, Children, Nonbinary, Eunuchs, and Intersex Individuals, and people living in Institutional Environments. Finally, the chapters related to gender-affirming treatment are Hormone Therapy, Surgery and Postoperative Care, Voice and Communication, Primary Care, Reproductive Health, Sexual Health, and Mental Health. Conclusions: The SOC-8 guidelines are intended to be flexible to meet the diverse health care needs of TGD people globally. While adaptable, they offer standards for promoting optimal health care and guidance for the treatment of people experiencing gender incongruence. As in all previous versions of the SOC, the criteria set forth in this document for gender-affirming medical interventions are clinical guidelines; individual health care professionals and programs may modify these in consultation with the TGD person.

Six year follow-up data on a leadless pacing system real life experience in comparison to data of the prospective trial

Funding Acknowledgements

Type of funding sources: None.

Introduction

The Micra™ leadless intracardiac pacing system has been introduced and implemented into clinical routine in 2015, with its next generation MICRA AV ™ in 2020. Feasibility, implantation safety, and acute success have been proven in the setting of controlled studies. Even apart from controlled studies, this new technology was beneficial for the individual patient. We aimed to report our single center follow-up (FU) data with a follow-up of up to six years.

Methods

In 246 patients (134 men; age: 79±8 y), Micra™ implantation was performed.

Pacemaker interrogation was performed one to seven days after implantation and during FU (1; 3; 6, then every 6 month) up to 72 months. Data were assessed in a real-life setting and compared with existing data of a controlled prospective trial.

Results

The implantation was successful in all 246 attempts with only one pericardial effusion as major complication. During follow up there were two patients developing severe heart failure symptoms resulting in an implantation of a CRT-device and switching of the leadless pacemaker system.

The average acute thresholds, sensing and impedance after system release were: 0.62±0.45V@0.24ms; 10,55±3,61mV and 697±178Ohm. During follow up of up to 5 years neither, pacemaker failure, nor infections were reported. Measurements were reevaluated for long-term thresholds, sensing and impedance: 0.44 ± 0.07V @ 0.24 ms; 17,25 ±4,65 mV and 572 ± 80 Ohm. During five years, no significant changes from acute to long-term measurements were detectable. In comparison to the controlled trial, our measurements of this real-life cohort were very similar.

Conclusion

In a real-life setting, the implantation of the leadless Micra™ system demonstrates a high rate of implantation success without major complications. We were also able to show stable long-term system parameters in the clinical setting of up to six years of follow up with a very good battery longevity of about 12 years.

A Thermodynamic Model for Interpreting Tryptophan Excitation-Energy-Dependent Fluorescence Spectra Provides Insight Into Protein Conformational Sampling and Stability

It is now over 30 years since Demchenko and Ladokhin first posited the potential of the tryptophan red edge excitation shift (REES) effect to capture information on protein molecular dynamics. While there have been many key efforts in the intervening years, a biophysical thermodynamic model to quantify the relationship between the REES effect and protein flexibility has been lacking. Without such a model the full potential of the REES effect cannot be realized. Here, we present a thermodynamic model of the tryptophan REES effect that captures information on protein conformational flexibility, even with proteins containing multiple tryptophan residues. Our study incorporates exemplars at every scale, from tryptophan in solution, single tryptophan peptides, to multitryptophan proteins, with examples including a structurally disordered peptide, de novo designed enzyme, human regulatory protein, therapeutic monoclonal antibodies in active commercial development, and a mesophilic and hyperthermophilic enzyme. Combined, our model and data suggest a route forward for the experimental measurement of the protein REES effect and point to the potential for integrating biomolecular simulation with experimental data to yield novel insights.

Real-world experience on the safety and effectiveness of Micra TPS in patients with pre-existing in situ CIEDs

Background

The Micra pre-market study showed that the Micra transcatheter pacing system could be safely implanted in patients with pacing indications. Patients with pre-existing cardiac implantable electronic devices (CIED) were excluded from this clinical trial; however, this group of patients might benefit from a leadless pacemaker especially when a lead fails or after incidence of system-related infections.

Objective

To determine the outcome of patients with a pre-existing CIED or lead that remains in situ at the time of Micra implant attempt.

Methods

Patients who had a pre-existing CIED and/or lead at the time of Micra implantation attempt were identified from the Micra Post-Approval Registry and Micra Acute Performance studies. Baseline characteristics were summarized, and a Fine-Gray competing risk model was used to compare risk for major complication through 24 months for patients with and without a pre-existing CIED.

Results

Of the 2323 patients included in the analysis, 111 patients had a pre-existing CIED or lead at the time of Micra implantation attempt that remained in situ. Types of pre-existing devices included 81 pacemakers (45 single chamber, 32 dual chamber, 4 of unknown type), 10 ICDs (2 single chamber, 2 dual chamber, 6 unknown type), 10 CRT devices (6 CRT-P, 4 CRT-D), 3 generators of unknown type, and 7 patients had only leads remaining. Patients with pre-existing devices were younger and less likely to have a pacing indication of bradyarrhythmia with atrial fibrillation compared to patients without pre-existing devices (p<0.001 for both). Patients with prior devices were more likely to have a condition precluding implant of a transvenous pacemaker (67.6% vs. 21.3%, p<0.001). The presence of a pre-existing CIED did not impact the outcome of the Micra TPS implant procedure: implant success was >99% for both cohorts. Mean follow-up duration was 21.2±14.3 months (range 0–56) for pre-existing devices patients and 23.3±15.8 months (range 0–62) for other patients. The rate of major complications through 24 months was 1.8% for patients with and 3.8% for patients without prior devices (p=0.36). There were no major complications related to device malfunction or device-device interaction. There were 6 system revisions in 4 patients with preexisting devices and 52 revisions in 51 patients without preexisting devices. Pacing thresholds for patients with and without prior devices were similar at implant (0.72 and 0.63, respectively; p=0.31) and remained stable through 12 months.

Conclusion

Micra can be safely and successfully implanted in patients with a pre-existing CIED remaining in situ. It should be considered a treatment option for patients in whom CIED extraction may be deemed high risk.

Funding Acknowledgement

Type of funding sources: Private company. Main funding source(s): Medtronic, Inc. Risk of major complications

Population pharmacokinetics of intravenous and oral ciprofloxacin in children to optimize dosing regimens

PURPOSE

This study aimed to characterize pharmacokinetics of intravenous and oral ciprofloxacin in children to optimize dosing scheme.

METHODS

Children treated with ciprofloxacin were included. Pharmacokinetics were described using non-linear mixed-effect modelling and validated with an external dataset. Monte Carlo simulations investigated dosing regimens to achieve a target AUC_0-24 h/MIC ratio ≥ 125.

RESULTS

A total of 189 children (492 concentrations) were included. A two-compartment model with first-order absorption and elimination best described the data. An allometric model was used to describe bodyweight (BW) influence, and effects of estimated glomerular filtration rate (eGFR) and age were significant on ciprofloxacin clearance.

CONCLUSION

The recommended IV dose of 10 mg/kg q8h, not exceeding 400 mg q8h, would achieve AUC_0-24 h to successfully treat bacteria with MICs ≤ 0.25 (e.g. Salmonella, Escherichia coli, Proteus, Haemophilus, Enterobacter, and Klebsiella). A dose increase to 600 mg q8h in children > 40 kg and to 15 mg/kg q8h (max 400 mg q8h, max 600 mg q8h if augmented renal clearance, i.e., eGFR > 200 mL/min/1.73 m²) in children < 40 kg would be needed for the strains with highest MIC (16% of Pseudomonas aeruginosa and 47% of Staphylococcus aureus). The oral recommended dose of 20 mg/kg q12h (not exceeding 750 mg) would cover bacteria with MICs ≤ 0.125 but may be insufficient for bacteria with higher MIC and a dose increase according bodyweight and eGFR would be needed. These doses should be prospectively confirmed, and a therapeutic drug monitoring could be used to refine them individually.

A leadless pacemaker in the real-world setting: Patient profile and performance over time

Funding Acknowledgements

Type of funding sources: Private company. Main funding source(s): Medtronic, Inc.

OnBehalf

Micra Acute Performance EMEA Investigators

Background

The first in-man implant of the Micra leadless pacemaker occurred in December 2013. While prior trials demonstrated a high implant success rate and favorable safety and efficacy results; whether the patient population and outcomes have changed over time is not well studied.

Purpose

To characterize the evolution of patient profile and outcomes for patients receiving a leadless pacemaker through the pre-market and post-market environment.

Methods

Patients undergoing a Micra leadless pacemaker implant attempt from the initial Micra Investigational Device Exemption [IDE] and current Micra studies (Micra post-approval registry [PAR], Micra acute performance [MAP] study) were analyzed. Patient characteristics and pericardial effusions regardless of severity were summarized.

Results

The 3466 patients included in the analysis underwent a Micra implant attempt and were enrolled during consecutive timeframes: patients from the Micra IDE study (n = 726) underwent a Micra implant attempt from 2013-2015, patients from the PAR (n = 1814) from 2015-2018, and patients from Micra MAP cohort (n = 926) from 2018 – 2020.  Implant success was &gt;99.0% in all 3 studies. Median age ranged from 78 – 79 years among the 3 studies without significant difference. There were more patients requiring dialysis in the MAP cohort compared to the PAR or IDE cohorts (10.3%, 7.9%, and 3.9%, respectively; P &lt; 0.001), but fewer patients with congestive heart failure (8.3%, 13.1%, and 18.0%; P &lt; 0.001). Pacing indication was significantly different between the studies, with fewer patients in MAP having an indication of bradyarrhythmia associated with atrial fibrillation (AF) and more having an indication associated with atrioventricular block without AF (P &lt; 0.001). The number of patients considered to be precluded for a transvenous pacemaker implant increased significantly from the initial IDE study to the PAR and MAP studies (6.2%, 23.9%, and 44.1%, respectively, P &lt; 0.001).  Implant site placement was mostly apical for the IDE but shifted to mostly septal placement in the PAR and MAP (septal placement: 33.3%, 64.0%, and 79.5%, respectively). The rate of pericardial effusion regardless of severity was 1.79% (n = 13) in the IDE, 0.83% (n = 15) in the PAR, and 0.97% (n = 9) in MAP (figure). Mean pacing thresholds among MAP EMEA patients were low (0.61 ± 0.40V) at implant and remained stable through 12 months (0.62 +/- 0.41V).

Conclusion

Despite patient differences over time, the Micra leadless pacemaker was implanted with a high success rate and a low perforation rate, in-line with prior reports. Abstract Figure. Pericardial effusion rate by study

417 COVID-19 and the Return to Head and Neck Outpatient Activity in The United Kingdom: What Is the New Normal?

Background

We aim to investigate current head and neck outpatient practices across the United Kingdom during the COVID-19 pandemic.

Method

A cross-sectional study comprising of an online 20-item survey was emailed to members of the British Association of Head and Neck Oncologists (BAHNO). Topics covered included safety measures, protective equipment used and protocols around the use of flexible nasendoscopy (FNE) in clinic.

Results

117 participants completed the survey covering 66 Trusts across the UK. There was a significant reduction in face-to-face clinic patients compared to pre-pandemic numbers. Room down-time after FNE ranged from 0-6 hours and there was a significant increase in allocated down-time after the patient had coughed or sneezed. Natural ventilation existed in 36% of clinics and the majority of responders didn’t know the calculated Air Change Per Hour (ACPH) of the room (77%). Where ACPH was known, it often did not match the allocated room down-time.

Conclusions

Adaptations are being made across the UK to maintain staff and patient safety, but more can still be done by liaising with hospital infectious diseases and the hospital estates team to clarify outpatient protocols.Outpatient activity will likely remain limited and alternative strategies will need to develop to manage the backlog in face-to-face clinics.

Zenker's diverticulum misinterpreted as a thyroid mass: Case report

We discuss an unusual presentation of Zenker's Diverticulum (ZD). A 76-year-old man presented with a left sided neck mass which was misdiagnosed as a thyroid mass due to the anatomical location and size. The ultrasound and fine needle-aspiration cytology findings were inconclusive, and a CT scan was then considered which reported a large pharyngeal pouch. Our recommendation is to consider an early CT scan in patient's where there is a clinical suspicion or risk factors for the development of pharyngeal pouch specially when the fine-needle aspiration cytology findings are inconclusive. This would reduce the risk of a delayed diagnosis which can prevent potential perforation of the pharyngeal pouch and development of mediastinitis.

•

Left sided neck mass misdiagnosed as thyroid mass.

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Zenker's Diverticulum is formed due to muscular weakness.

•

Pharyngeal pouch symptoms mimic head and neck cancer presentation.

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Barium swallow is a gold standard investigation for pharyngeal pouch.

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Pharyngeal pouch can be treated with endoscopic or external surgical approaches.

[Echocardiographic assessment of myocardial function during His bundle and right ventricular pacing]

INTRODUCTION

In patients with pacemaker (PM) therapy, His bundle stimulation (HBS) may lead to a more synchronous activation of the left ventricle (LV) than conventional right ventricular stimulation (RVS). In this study, we investigated to which extent this effect can be objectified by means of contemporary echocardiographic functional imaging.

METHODS

In all, 15 RVS patients (6 women, mean age 76.6 ± 4.1 years) and 15 HBS patients (6 women, mean age 74.6 ± 3.7 years) underwent echocardiography with and without cardiac pacing. Besides LV end-diastolic volume (EDV), ejection fraction (EF), and global strain (GLS), we measured global and regional myocardial work and LV efficiency based on noninvasive pressure-strain loops.

RESULTS

In all HBS patients, optimization of PM settings resulted in immediate changes in myocardial function parameters. With pacing, RVS patients showed a higher decrease in EF and GLS than HBS patients. Global LV work and LV work efficiency decreased significantly only in RVS patients.

CONCLUSION

Changes in regional and global myocardial function can by proven and quantified by functional echocardiography. In patients under PM therapy, HBS shows functional advantages in comparison to conventional RVS.

P1468Four years follow-up of leadless pacing system single center real life experience compared to data of the prospective trial

Funding Acknowledgements

none

OnBehalf

Cologne Registry

Introduction

The Micra™ leadless intracardiac pacing system has been introduced and implemented into clinical routine more than three years ago. Feasibility, implantation safety and acute success have been proven in the setting of controlled studies. Additionally few real- life and post-implantation data exist.  We aimed to report our single center follow-up (FU) data in comparison with the results of the prospective controlled  Micra™- studie.

Methods

In 112 patients (69 men; age: 79 ± 10 y) successful Micra™ implantation was performed.Pacemaker interrogation was performed one to seven days after implantation and during FU (1; 3; 6, than every 6 month) up to 48 month. Data were assessed in a real-life setting and compared with existing data of the controlled prospectiv trial.

Results

The implantation was successful in all 112 attempts without procedure or device-related major complications. During Follow up there was one patient developing severe heart failure symptoms resulting in an implantation of a CRT-device and switching of the leadless pacemaker system.

The average acute thresholds, sensing and impedance after system release were: 0.63 ± 0.42V@0.24ms; 9,94 ± 3,61mV and 705 ± 166 Ohm. During follow up of up to 4 years neither, pacemaker failure, nor infections were reported. Measurements were reevaluated for long-term thresholds, sensing and impedance: 0.54 ± 0.16V @ 0.24 ms; 16,15 ±4,22 mV and 579 ± 133 Ohm. In the first three years no significant changes from acute to long-term measurements were detectable.  In comparison to the data of the controlled trial the measurements of our real-life cohort was very similar.

Conclusion

In a real life setting the implantation of the leadless Micra™ system demonstrates high rate of implant success without major complications. Also shown were stable long-term system parameters in the clinical setting of up to two years of follow up. These data of every day clinical practice support the findings of the prospectiv trials.

553 Acute re-distribution of regional left ventricular work by cardiac resynchronization therapy determines long-term remodelling

Background

In patients with dilated cardiomyopathy and left bundle branch block (LBBB), different regions of the left ventricle (LV) have been shown to perform different amounts of work. In this study, we investigate the acute impact of cardiac resynchronization therapy (CRT) on regional LV work distribution and its relation to long-term reverse-remodelling.

Methods

We recruited 140 heart failure patients, referred for CRT. Regional myocardial work was calculated from non-invasive echocardiographic segmental stress-strain-loop-area before and immediately after CRT. The magnitude of volumetric reverse-remodelling was determined from the change in LV end-systolic volume (ESV), 11 ± 3 months after implantation. Characteristics of patients with the lowest and highest quartile of LV ESV reverse remodelling (LV ESV reduction of less than 10% and LV ESV reduction of more than -48%) were compared.

Results

Before CRT, myocardial work showed significant differences among the walls of the LV (Figure A). CRT caused an acute re-distribution of myocardial work, on average with most increase in the septum and most decrease laterally (all walls p &lt; 0.05) and lead to a homogeneous work distribution (Figure B). The acute change in the difference between lateral and septal wall work (Δ Lateral-to-septal work) correlated significantly with LV ESV reverse-remodelling (r = 0.63, p &lt; 0.0001). The smallest changes in work were seen in the patients with the least LV ESV reverse remodelling (Figure C, red markers), while patients with the most LV ESV reverse remodelling showed the largest changes in work (Figure C, green markers). In multivariate linear regression analysis, including conventional parameters such as pre-implant QRS duration, LV ejection fraction, LV end-diastolic volume and global longitudinal strain, the re-distribution of work across the septal and lateral walls appeared as the strongest determinant of volumetric reverse-remodelling after CRT (R²=0.393, p &lt; 0.0001).

Conclusions

The acute re-distribution of regional myocardial work between the septal and lateral wall of the left ventricle is an important determinant of long term reverse-remodelling after CRT-implantation. Our data suggest that modification of regional loading is the mode of action of CRT treatment.

Abstract 553 Figure.

Assessing the efficacy and cost of detergents used in a primary care automated washer disinfector

Background

Cleaning of re-usable medical devices is a critical control point in the decontamination cycle, although defined end-points of the process are controversial.

Objective

Investigate cleaning efficacy and cost of different detergent classes in an automated washer disinfector (AWD) designed for dental practice.

Methods

Loads comprised test soiled dental hand instruments in cassettes and extraction forceps. Residual protein assayed using the International standard method (ISO 15883-5:2005) 1% SDS elution with ortho-phthalaldehyde (OPA) or GBox technology (on instrument OPA analysis). Short (60 minutes) and long (97 minutes) AWD cycles were used with four different classes of detergents, tap water and reverse osmosis water.

Results

SDS elution analysis (N = 612 instruments) demonstrated four detergents with both wash cycles achieved equivalent cleanliness levels and below a threshold of 200 μg protein/instrument. GBox methodology (N = 575) using UK Department of Health threshold of 5 μg/instrument side demonstrated that tap water performed with the greatest efficacy for all types of instruments and cycle types.

Conclusions

Using International standard methodology, different detergent classes had equivalence in cleaning efficacy. Cheaper detergents used in this study performed with similar efficacy to more expensive solutions. Findings emphasise the importance of validating the detergent (type and concentration) for each AWD.

P1238Acute re-distribution of myocardial work by cardiac resynchronization therapy determines long-term remodelling of the left ventricle

Background

In patients with dilated cardiomyopathy and left bundle branch block (LBBB), different regions of the left ventricle (LV) have been shown to perform different amounts of work. In this study, we investigate the acute impact of cardiac resynchronization therapy (CRT) on regional LV work distribution and its relation to long-term reverse-remodelling.

Methods

We recruited 130 heart failure patients, referred for CRT. Regional myocardial work was calculated from non-invasive echocardiographic segmental stress-strain-loop-area before and immediately after CRT. The magnitude of volumetric reverse-remodelling was determined from the change in LV end-systolic volume (ESV), 11±2 months after implantation. Characteristics of patients with the lowest and highest quartile of LV ESV reverse remodelling (ΔLV ESV <−9% and ΔLV ESV >−48%) were compared.

Results

Before CRT, myocardial work showed significant differences among the walls of the LV (Figure 1A). CRT caused an acute re-distribution of myocardial work, on average with most increase in the septum and most decrease laterally (all walls p<0.05) and lead to a homogeneous work distribution (Figure 1B). The acute change in the difference between lateral and septal wall work (Δlateral − septal work) correlated best and significantly with LV ESV reverse-remodelling (r=0.62, p<0.0001). The smallest changes in work were seen in the patients with the least LV ESV reverse remodelling (Figure 1C, red markers), while patients with the most LV ESV reverse remodelling showed the largest changes in work (Figure 1C, green markers). In a multivariate-linear-regression-analysis, including pre-implant QRS duration, LVEF, LV EDV and GLS, the re-distribution of work remained as the strongest determinant of volumetric reverse-remodelling after CRT (r=0.63, p<0.0001).

Figure 1

Conclusions

The acute re-distribution of regional myocardial work between the septal and lateral wall of the left ventricle is the main determinant of long term reverse-remodelling after CRT-implantation. Our data suggest that modification of regional loading is the mode of action of CRT treatment.

P3641Matrix Metalloproteinase-2 polymorphisms are associated with prognosis of patients with symptomatic coronary artery disease

Background

Matrix Metalloproteinase-2 (MMP-2) is involved in regulation and proliferation of vascular and endothelial cells and is therefore an important component of atherosclerotic vessels. Inhibition of MMP-2 activity is associated with improvement of cardiac function in animal models after myocardial infarction. MMP-2 single nucleotide polymorphisms (SNPs) might alter MMP-2 expression and therefore influence prognosis in patients with symptomatic coronary artery disease (CAD).

Methods and results

Genotyping for selected MMP-2 SNPs variants (rs2241145, rs2285053, rs2287076, rs243865, rs7201) was performed in 943 consecutive patients with symptomatic CAD. All patients were followed-up for all-cause death (ACD), myocardial infarction (MI) and ischemic stroke (IS) for 360 days. The primary combined endpoint (CE) consisted of either first occurrence of ACD, and/or MI, and/or IS. Secondary endpoints were defined as the single events of ACD or MI. Homozygous carriers of major allele (rs2241145, rs2287076) showed significantly better event-free survival than carriers of the minor allele for CE (Log rank = 0.022 and Log rank= 0.015, respectively). Furthermore, homozygous carriers of major allele (rs2241145, rs2285053, rs2287076) showed significantly better event-free survival for ACD (Log rank= 0.047, Log rank= 0.006 and Log rank= 0.023, respectively). In multivariate analysis, MMP-2 rs2241145, rs2287076 and rs2285053 were significantly and independently associated with CE and ACD.

Figure 1

Conclusions

MMP-2 rs2241145, rs2287076 and rs2285053 are associated with prognosis and might be valuable for further risk stratification in CAD patients.

Acknowledgement/Funding

DFG, KFO 274, CRC TR 240

P3643Junctional Adhesion Molecule-A (JAM-A) polymorphisms influence serum levels of soluble JAM-A and are associated with long term prognosis in coronary artery disease

Aims

Junctional adhesion molecule A (JAM-A/F11R) is a cell adhesion molecule. Membrane associated JAM-A mediates platelet aggregation, secretion, adhesion, and spreading. Plasma levels of JAM-A are elevated in hypertension and atherosclerosis. This study was designed to investigate the impact of JAM-A single nucleotide polymorphisms (SNPs) on circulatory JAM-A levels and prognosis in patients with symptomatic coronary artery disease (CAD).

Methods and results

JAM-A SNP analysis (JAM-A F11R rs2774276 and rs790056) was performed in 943 patients with symptomatic CAD. All patients were tracked for all-cause death (ACD), myocardial infarction (MI), and ischemic stroke (IS) for 1080 days. The primary combined endpoint (CE) was defined as a composite of ACD and/or MI and/or IS. Secondary endpoints were defined as the single events of ACD and MI. Homozygote carriers of the minor allele (F11R rs2774276 and rs790056) showed significantly worse event-free survival for MI when compared with major allele carriers (Log rank = 0.011 and log rank = 0.031, respectively). No significant differences could be shown for the CE and ACD. Of note, in multivariate analysis, both SNPs were significantly and independently associated with MI. Furthermore, serum levels of soluble JAM-A were elevated in homozygote carriers of minor allele when compared to major allele carriers. Finally, serum levels of soluble JAM-A were significantly elevated in patients with MI when compared to stable CAD (p=0.036).

Figure 1

Conclusion

JAM-A SNPs are associated with prognosis in patients with symptomatic coronary artery disease. Furthermore, JAM-A SNPs might influence serum concentration of soluble JAM-A. Finally, serum concentration of soluble JAM-A is higher in patients with myocardial infarction when compared to stable coronary artery disease. These findings suggest JAM-A as a valuable biomarker for risk stratification and tailoring therapies in patients with coronary artery disease.

Acknowledgement/Funding

DFG-KFO274, CRC/Transregio 240

Development and validation of a novel prognostic score to predict survival in patients with metastatic colorectal cancer: the metastatic colorectal cancer score (mCCS)

AIM

Published prognostic scores for metastatic colorectal cancer (mCRC) are based on data from highly selected patient subgroups with specified first-line treatments and may not be applicable to routine practice. We have therefore developed and validated the metastatic colorectal cancer score (mCCS) to predict overall survival (OS) for patients with mCRC.

METHOD

A total of 1704 patients from the prospective, multicentre cohort study Tumour Registry Colorectal Cancer were separated into learning (n = 796) and validation (n = 908) samples. Using a multivariate Cox regression model, the six-factor mCCS was established.

RESULTS

The six independent prognostic factors for survival are as follows: two or more metastatic sites at the start of first-line treatment, tumour grading ≥ G3 at primary diagnosis, residual tumour classification ≥ R1/unknown, lymph node ratio (of primary tumour) ≥ 0.4, tumour stage ≥ III/unknown at primary diagnosis and KRAS status mutated/unknown. The mCCS clearly separated the learning sample into three risk groups: zero to two factors (low risk), three factors (intermediate risk) and four to six factors (high risk). The prognostic performance of the mCCS was confirmed in the validation sample and additionally stratified a large sample of patients with known (K)RAS mutation status.

CONCLUSION

The novel prognostic score, mCCS, clearly defines three prognostic groups for OS at start of first-line therapy. For oncologists, the mCCS represents a simple and easy-to-apply tool for routine clinical use, as it is based on objective tumour characteristics and can assist with treatment decision-making and communication of the prognosis to patients.

Gene expression signature associated with in vitro dexamethasone resistance and post-induction minimal residual disease in pediatric T-cell acute lymphoblastic leukemia

10033

Background: T-cell acute lymphoblastic leukemia (T-ALL) is a genetically heterogeneous disease, which has largely precluded the use of genetic mutations for risk stratification. We hypothesized that despite this heterogeneity, diverse T-ALLs may have functional similarities that underlie patterns of chemotherapy sensitivity. Methods: We used flow cytometry to evaluate in vitro dexamethasone (DEX) sensitivity and baseline expression of signal transduction effectors and BCL2-family proteins in 68 fresh diagnostic T-ALL samples from patients enrolled on the Children’s Oncology Group (COG) trial AALL1231. We also performed RNA-sequencing (RNA-seq) on 40 AALL1231 samples and used hierarchical clustering and linear regression to analyze these and published T-ALL RNA-seq data from COG AALL0434. Comparisons between groups were made using t-tests and Fisher’s exact tests. Results: Of the proteins analyzed, only high BCL2 expression was significantly associated with increased in vitro DEX resistance (p = 0.002). Hierarchical clustering of the AALL1231 RNA-seq data identified two distinct clusters. Cluster 1 was associated with significantly higher BCL2 transcript expression (p = 0.0002) and in vitro DEX resistance (p = 0.04) relative to cluster 2. We defined a gene set consisting of the top 210 differentially expressed genes between these clusters and applied this gene set to the COG AALL0434 cohort. In this analysis, the early T-cell precursor (ETP) and near-ETP samples clustered together (p < 0.0001) in cluster 1 along with 39 of 146 non-ETP samples. Not only did these cluster 1 non-ETP samples have significantly higher BCL2 transcript expression relative to the non-ETP samples in cluster 2 (p < 0.0001), but 54% of these non-ETP samples were minimal residual disease (MRD) positive (≥0.01%) at the end of induction, as opposed to only 16% of the non-ETP samples in cluster 2 (p < 0.0001). Conclusions: Gene expression profiling identifies non-ETP T-ALLs that cluster with ETP/near-ETP T-ALLs and have significantly higher BCL2 expression and increased rates of post-induction MRD.

Development and external validation of nomograms in oropharyngeal cancer patients with known HPV-DNA status: a European Multicentre Study (OroGrams)

BACKGROUND

The proxy marker for human papillomavirus (HPV), p16, is included in the new AJCC 8th/UICC 8th staging system, but due to incongruence between p16 status and HPV infection, single biomarker evaluation could lead to misallocation of patients. We established nomograms for overall survival (OS) and progression-free survival (PFS) in patients with oropharyngeal squamous cell carcinoma (OPSCC) and known HPV-DNA and p16 status, and validated the models in cohorts from high- and low-prevalent HPV countries.

METHODS

Consecutive OPSCC patients treated in Denmark, 2000-2014 formed the development cohort. The validation cohorts were from Sweden, Germany, and the United Kingdom. We developed nomograms by applying a backward-selection procedure for selection of variables, and assessed model performance.

RESULTS

In the development cohort, 1313 patients, and in the validation cohorts, 344 German, 503 Swedish and 463 British patients were included. For the OS nomogram, age, gender, combined HPV-DNA and p16 status, smoking, T-, N-, and M-status and UICC-8 staging were selected, and for the PFS nomogram the same variables except UICC-8 staging. The nomograms performed well in discrimination and calibration.

CONCLUSIONS

Our nomograms are reliable prognostic methods in patients with OPSCC. Combining HPV DNA and p16 is essential for correct prognostication. The nomograms are available at www.orograms.org .

Clinically actionable mutation profiles in patients with cancer identified by whole-genome sequencing

Next-generation sequencing (NGS) efforts have established catalogs of mutations relevant to cancer development. However, the clinical utility of this information remains largely unexplored. Here, we present the results of the first eight patients recruited into a clinical whole-genome sequencing (WGS) program in the United Kingdom. We performed PCR-free WGS of fresh frozen tumors and germline DNA at 75× and 30×, respectively, using the HiSeq2500 HTv4. Subtracted tumor VCFs and paired germlines were subjected to comprehensive analysis of coding and noncoding regions, integration of germline with somatically acquired variants, and global mutation signatures and pathway analyses. Results were classified into tiers and presented to a multidisciplinary tumor board. WGS results helped to clarify an uncertain histopathological diagnosis in one case, led to informed or supported prognosis in two cases, leading to de-escalation of therapy in one, and indicated potential treatments in all eight. Overall 26 different tier 1 potentially clinically actionable findings were identified using WGS compared with six SNVs/indels using routine targeted NGS. These initial results demonstrate the potential of WGS to inform future diagnosis, prognosis, and treatment choice in cancer and justify the systematic evaluation of the clinical utility of WGS in larger cohorts of patients with cancer.

Abstract PR14: Polycomb repressive complex 2 inactivation induces primary chemotherapy resistance in T-ALL by upregulating the TRAP1 mitochondrial chaperone

The tendency of mitochondria to undergo or resist BCL2-controlled apoptosis (so-called mitochondrial priming) is a powerful predictor of the outcome of cytotoxic chemotherapy for cancer. To fully exploit this finding, it will be important to understand the molecular genetic contexts responsible for the relative mitochondrial priming of chemotherapy-sensitive versus resistant cell populations. Here we report that mitochondrial apoptosis resistance in T-cell acute lymphoblastic leukemia (T-ALL) is mediated by inactivation of polycomb repressive complex 2 (PRC2) and consequent downstream upregulation of the TRAP1 gene, which encodes a mitochondrial chaperone protein of the HSP90 family. In clinical samples from 47 T-ALL patients, we found that loss-of-function mutations in any of three core components of PRC2 (EZH2, EED or SUZ12) were associated with resistance to mitochondrial apoptosis, as assessed by BH3 profiling (P = 0.015). In human T-ALL cells, PRC2 depletion induced resistance to mitochondrial apoptosis induction, as assessed by caspase 3/7 activation or annexin V/PI staining, in response to multiple antileukemic drugs with distinct mechanisms of action, including dexamethasone, doxorubicin, vincristine, and asparaginase (P &lt; 0.01). In mouse immature T-cell progenitors, haploinsufficiency for the PRC2 components Ezh2 or Eed was sufficient to induce resistance to mitochondrial apoptosis, as assessed by BH3 profiling analysis (P ≤ 0.01). PRC2 is a histone-modifying complex whose activity is strongly associated with transcriptional repression. We found that PRC2 represses transcription of TRAP1, a nuclearly encoded, mitochondrially localized chaperone of the HSP90 family. Importantly, TRAP1 overexpression was necessary to induce resistance to chemotherapy-induced apoptosis downstream of PRC2 inactivation (P &lt; 0.001), while pharmacologic inhibition of TRAP1 synergized with antileukemic drugs in PRC2-deficient leukemic cells. These findings demonstrate the importance of relative mitochondrial apoptotic priming as a prognostic factor in T-ALL, and implicate mitochondrial chaperone function as a molecular determinant of response to cancer chemotherapy, suggesting a rationale for targeted therapeutic intervention.

This abstract is also being presented as Poster 07.

Citation Format: Ingrid Aries, Triona Ni Chonghaile, Salmaan Karim, Sebastian Balbach, Melissa Burns, Gayle Pouliot, Stevenson Kristen, Donna Neuberg, Meenakshi Devidas, Loh Mignon, Stephen Hunger, Stuart Winter, David Teachey, Karen Rabin, Kimberly Dunsmore, Brent Wood, Lewis Silverman, Stephen Sallan, Peter Van Vlierberghe, Stuart H. Orkin, Anthony G. Letai, Alejandro Gutierrez. Polycomb repressive complex 2 inactivation induces primary chemotherapy resistance in T-ALL by upregulating the TRAP1 mitochondrial chaperone [abstract]. In: Proceedings of the Second AACR Conference on Hematologic Malignancies: Translating Discoveries to Novel Therapies; May 6-9, 2017; Boston, MA. Philadelphia (PA): AACR; Clin Cancer Res 2017;23(24_Suppl):Abstract nr PR14.

Sodium phosphate enemas do not worsen renal function among hospitalized patients with mild to moderate renal failure: a matched, case-control study

BACKGROUND

Sodium phosphate enemas (SPEs) are widely used among hospitalized patients despite their potential to worsen renal failure.

AIM

We decided to assess the extent to which this side effect is clinically relevant.

DESIGN

We conducted a matched case-control, retrospective study in a cohort of hospitalized patients.

METHODS

Patients treated and untreated with SPEs were matched for age, gender, baseline creatinine, usage of certain medications and several background diagnoses. Three groups of matched patients (whole study cohort, patients with baseline creatinine > 1.5 mg/dl and those with baseline creatinine > 2 mg/dl) were compared with regards to their creatinine and blood electrolyte concentrations during 3 consecutive hospitalization days after SPE application.

RESULTS

Four hundred and twelve patients were included in this study of which 206 were treated by single SPEs. Exact matching was done for the whole study cohort, for 108 patients with baseline creatinine > 1.5 mg/dl and for 58 patients with baseline creatinine > 2 mg/dl. During 3 consecutive days after SPEs, the maximal blood concentrations of creatinine, phosphor and potassium did not differ significantly between treated patients and matched controls, in all three patients' groups.

CONCLUSION

Application of SPEs neither seem to worsen mild to moderate renal failure, nor are associated with hyperphosphatemia or hyperkalemia in patients hospitalized in internal medicine departments.

Nodular fasciitis of soft tissue over the mandible

Nodular fasciitis (NF) is an unusual, benign condition which can mimic more sinister, sarcomatous lesions both clinically and histologically. This case report presents a 35-year-old male, with a rapidly growing mass on the border of his left mandible, referred to a specialist head and neck unit. The initial presentation, radiology and cytology were initially inconclusive and the possibility of a malignant process was considered. Final histology was that of NF, the treatment of which is complete surgical excision. Therefore, NF is an important differential to consider when assessing similar clinical presentations, as highlighted in this case report.

Osteocondromatose em gato: relato de caso

RESUMO A osteocondromatose é caracterizada por nódulos únicos ou múltiplos decorrentes de um crescimento ósseo excessivo benigno. É encontrada em cães, gatos, equinos e humanos. Em felinos, tem maior incidência dos dois aos quatro anos de idade. A etiologia em gatos está relacionada ao vírus da leucemia felina, e também já foi encontrada relação com o fibrossarcoma. A manifestação clínica depende do local acometido e do tamanho da lesão. O diagnóstico definitivo é por meio de histopatologia e o prognóstico é desfavorável, pois ocorrem muitas recidivas. Este relato de caso objetiva descrever a apresentação dessa enfermidade em um felino jovem.

Failure of non-vacuum steam sterilization processes for dental handpieces

BACKGROUND

Dental handpieces are used in critical and semi-critical operative interventions. Although some dental professional bodies recommend that dental handpieces are sterilized between patient use there is a lack of clarity and understanding of the effectiveness of different steam sterilization processes. The internal mechanisms of dental handpieces contain narrow lumens (0.8-2.3 mm) which can impede the removal of air and ingress of saturated steam required to achieve sterilization conditions.

AIM

To identify the extent of sterilization failure in dental handpieces using a non-vacuum process.

METHODS

In-vitro and in-vivo investigations were conducted on widely used UK bench-top steam sterilizers and three different types of dental handpieces. The sterilization process was monitored inside the lumens of dental handpieces using thermometric (TM; dataloggers), chemical indicator (CI), and biological indicator (BI) methods.

FINDINGS

All three methods of assessing achievement of sterility within dental handpieces that had been exposed to non-vacuum sterilization conditions demonstrated a significant number of failures [CI: 8/3024 (fails/no. of tests); BI: 15/3024; TM: 56/56] compared to vacuum sterilization conditions (CI: 2/1944; BI: 0/1944; TM: 0/36). The dental handpiece most likely to fail sterilization in the non-vacuum process was the surgical handpiece. Non-vacuum sterilizers located in general dental practice had a higher rate of sterilization failure (CI: 25/1620; BI: 32/1620; TM: 56/56) with no failures in vacuum process.

CONCLUSION

Non-vacuum downward/gravity displacement, type N steam sterilizers are an unreliable method for sterilization of dental handpieces in general dental practice. The handpiece most likely to fail sterilization is the type most frequently used for surgical interventions.