Surgical management of the diabetic foot: The current evidence

The prevalence of diabetes mellitus and its associated complications, particularly diabetic foot pathologies, poses significant healthcare challenges and economic burdens globally. This review synthesises current evidence on the surgical management of the diabetic foot, focusing on the interplay between neuropathy, ischemia, and infection that commonly culminates in ulcers, infections, and, in severe cases, amputations. The escalating incidence of diabetes mellitus underscores the urgency for effective management strategies, as diabetic foot complications are a leading cause of hospital admissions among diabetic patients, significantly impacting morbidity and mortality rates. This review explores the pathophysiological mechanisms underlying diabetic foot complications and further examines diabetic foot ulcers, infections, and skeletal pathologies such as Charcot arthropathy, emphasising the critical role of early diagnosis, comprehensive management strategies, and interdisciplinary care in mitigating adverse outcomes. In addressing surgical interventions, this review evaluates conservative surgeries, amputations, and reconstructive procedures, highlighting the importance of tailored approaches based on individual patient profiles and the specific characteristics of foot pathologies. The integration of advanced diagnostic tools, novel surgical techniques, and postoperative care, including offloading and infection control, are discussed in the context of optimising healing and preserving limb function.

Immune mechanisms of depression in rheumatoid arthritis

Depression is a common and disabling comorbidity in rheumatoid arthritis that not only decreases the likelihood of remission and treatment adherence but also increases the risk of disability and mortality in patients with rheumatoid arthritis. Compelling data that link immune mechanisms to major depressive disorder indicate possible common mechanisms that drive the pathology of the two conditions. Preclinical evidence suggests that pro-inflammatory cytokines, which are prevalent in rheumatoid arthritis, have various effects on monoaminergic neurotransmission, neurotrophic factors and measures of synaptic plasticity. Neuroimaging studies provide insight into the consequences of inflammation on the brain (for example, on neural connectivity), and clinical trial data highlight the beneficial effects of immune modulation on comorbid depression. Major depressive disorder occurs more frequently in patients with rheumatoid arthritis than in the general population, and major depressive disorder also increases the risk of a future diagnosis of rheumatoid arthritis, further highlighting the link between rheumatoid arthritis and major depressive disorder. This Review focuses on interactions between peripheral and central immunobiological mechanisms in the context of both rheumatoid arthritis and major depressive disorder. Understanding these mechanisms will provide a basis for future therapeutic development, not least in depression.

Surgical Interventions for Chronic Ulnar Collateral Ligament Injuries of the Thumb: A Systematic Review

Background: There is no consensus for the appropriate surgical management of symptomatic chronic ulnar collateral ligament (UCL) injuries of the thumb. The aim of this study is to systematically review the treatment of chronic thumb metacarpophalangeal (MCP) joint UCL injuries to determine the optimal approach to treatment. Methods: A systematic review of PubMed, Medline, Embase and ePub Ahead of Print was performed in accordance with Preferred Reporting of Items in Systematic Review and Meta-Analysis (PRISMA) guidelines. Results: Data from 11 studies using various surgical techniques in 245 thumbs were heterogenous and meta-analysis of results not possible. These data were qualitatively assessed. Direct repair, reconstruction with free tendon grafts and arthrodesis all demonstrated favourable outcomes with patient-reported outcome measures (PROMs). Conclusions: Direct repair can be safely performed more than 2 months following injury. Arthrodesis may be considered in heavy manual labourers or those with osteoarthrosis. Tendon grafting is safe, yet the optimal type and configuration are yet to be determined for reconstructive methods. Level of Evidence: Level III (Therapeutic).

How a Chain Can Be Extended While Its Bonds Are Compressed

Extending polymer chains results in a positive chain tension, f_ch, primarily due to conformational restrictions. At the level of individual bonds, however, tension, f_b, is either negative or positive and depends on both chain tension and bulk pressure. Typically, the chain and bond tension are assumed to be directly related. In specific systems, however, this dependence may not be intuitive, whereby f_ch increases while f_b decreases; i.e., the entire chain is extended while bonds are compressed. Specifically, increasing the grafting density of a polymer brush results in chain extension along the direction perpendicular to the grafting surface while the underlying bonds are compressed. Similarly, upon compression of polymer networks, the extension of chains oriented in the "free" direction increases while their bonds are getting more compressed. We demonstrate this phenomenon in molecular dynamics simulations and explain it by the fact that the pressure contribution to f_b is dominant over a wide range of network deformations and brush grafting densities.

A cost-consequence analysis of eLearning videos designed to supplement the consent process in lower limb arthroplasty

INTRODUCTION

Since the Montgomery ruling in 2015 surgeons have been tasked with identifying material risk when taking informed consent. Despite this, there has been limited uptake of technological aids to supplement the consent process although such aids are shown to improve patient knowledge and satisfaction. ConsentPLUS is a free-to-access website with bite-sized educational videos designed to clearly explain lower limb arthroplasty procedures to patients and aid their consent.

METHODS

The authors performed a prospective cost-consequence analysis, outlining any costs associated with the intervention and any quantitative or qualitative impacts the intervention may have on patients.

RESULTS

A total of 3,143 consecutive patients were identified who were undergoing total knee or hip replacement in 25 elective NHS orthopaedic units. The total cost of development and projected 10-year running fees for ConsentPLUS total £75,000. Health Foundation support means the service is free-to-access for centres throughout the UK. Mean exposure time per patient was 10min 29s, equivalent to £185,437 of additional contact time according to the National Tariff. Mean clinic time was reduced by 17min owing to the earlier identification of material risk. Patient knowledge on pre- and post-video quizzes increased from 7.01 to 9.08 following eLearning (paired t-test = 0.998). The process had an overall satisfaction rate of 97%.

CONCLUSION

Educational eLearning videos are an accessible and digestible way to supplement the consent process. This enables earlier identification of material risk in clinics owing to improved patient knowledge, leading to increased patient satisfaction with arthroplasty consenting.

Tibial Intramedullary Nailing by Suprapatellar Approach: Is It Quicker and Safer?

Background

With the increasingly accepted method of suprapatellar tibial nailing for tibial shaft fractures, we aimed to compare intraoperative and postoperative outcomes of infrapatellar (IP) vs suprapatellar (SP) tibial nails.

Methods

This is a retrospective cohort analysis of 34 SP tibial nails over three years vs 24 IP tibial nails over a similar time frame. We compared total radiation dose (TRD), patient positioning time (PPT), fracture healing and follow up time. Knee pain in the SP group was evaluated utilising the Hospital for Special Surgery (HSS) Knee Injury and Osteoarthritis Outcome Score (KOOS).

Results

Fifty-eight patients with a mean age of 43 years were included. Mean intraoperative radiation dose for SP nails was 61.78 cGy (range: 11.60-156.01 cGy) vs 121.09 cGy (range: 58.01-18.03 cGy) for IP nails (p < 0.05). Mean PPT for SP nails was 10 minutes vs 18 minutes for IP nails (p < 0.05). All fractures united in the SP group vs one non-union in the IP group. Mean follow up was 5.5 months vs 11 months in the IP and SP groups, respectively. Mean KOOS was 7 (range: 0-22) at six months for the SP group.

Conclusion

The semi-extended position (SP group) leads to reduced TRD because of ease of imaging. Patients showed improved outcomes with shorter follow up and fracture union in all patients (SP group). The KOOS revealed that SP nail patients had minimal pain and good knee function. This study establishes a management and patient-reported outcome measures (PROMs) baseline for ongoing evaluation of SP nails.

Generation of Allogeneic CAR T Cells through Specific Degradation of the T Cell Antigen Receptor by E3 Ubiquitin Ligase Fusion Proteins

Receptor downregulation is instrumental for many therapeutic interventions. Receptor knockout through gene-editing technologies is efficient but can introduce off-target mutations and chromothripsis. Regulation of gene expression at the protein level is a promising alternative. Here, we present results showing the targeted T cell antigen receptor (TCR) degradation using chimeric E3 fusion proteins that we call Receptor Targeting Chimeras (ReceptorTAC). We show that TCR degradation is dependent on enzymatically active, membrane-anchored E3 ligase variants. TCR specificity was achieved by direct fusion of an E3 domain to the CD3ζ transmembrane sequence. Jurkat and primary T cells stably expressing the ReceptorTAC constructs showed significantly reduced responses to TCR stimulation. We also used our ReceptorTAC technology to generate TCR-deficient, claudin18.2-specific CAR T cells, where the activity of the CAR was unaffected by the expression of the ReceptorTAC. These data indicate that our ReceptorTAC molecule can be used to generate allogeneic CAR T cells.

Simultaneous Bilateral Anterior Inferior Iliac Spine Avulsion Injury in an Adolescent Cross-Country Runner

Introduction:

Pelvic apophyseal injuries are common in young athletes where muscle strength exceeds the tensile strength of the physis. Sequential bilateral injuries are exceedingly rare, and little is known of their mechanism.

Case Presentation:

A 15-year-old male cross-country runner presented with bilateral hip pain after sprint training. The patient describes going “flat out” and “overstriding” before collapsing with immediate pain. MRI imaging confirmed an acute bilateral Anterior Inferior Iliac Spine Injury (AIIS). Conservative management included protected weight-bearing, a hip strengthening program and graded return to play. At 6 months, the patient returned to full sporting activities with no symptoms.

Conclusion:

We present a unique case of bilateral AIIS avulsion that offers insight into the potential mechanisms and adds to the evidence that these injuries may be managed successfully with conservative treatment.

SP9.1.12 Bone protection in neck of femur fracture patients in a DGH without a fracture liaison service

Introduction

In England and Wales, there are approximately 75,000 proximal femoral fractures per year. Bone protection is vital in these patients and a key recommendation of NICE guidelines (CG124) for multidisciplinary approach in hip fracture management.

Method

Data were collected retrospectively using clinical portal, admission records and medication charts. The data were inputted into the FRAX calculator to calculate a patient’s risk of developing an osteoporotic fracture; depending on their risk they would be appropriate for bone protection or DEXA scanning for further assessment. As certain data criteria were not available for the FRAX calculation, risk calculation was underscored i.e. if parental hip fracture status was not known.

Results

A total of 59 patients were audited between July and October 2019. Of those patients, 25 were calculated as high risk, however, only 6 patients had adequate bone protection. 19 patients were deemed intermediate risk and would benefit from a DEXA scan for further assessment. Of those 19 patients, only 8 had adequate bone protection. DEXA scan was only requested for 2 of the patients who were intermediate or high risk. In the year following, 4 patients have had another fracture, with 3 of those patients not on any bone protection medication and had a high risk FRAX calculation.

Conclusion

Following a local meeting; a proforma was piloted to identify patients at risk and requiring bone protection. With the help of a dedicated orthopaedic pharmacist and nurse practitioners, continuity of care can be achieved to aid patients long-term wellbeing.

The role for JAK inhibitors in the treatment of immune-mediated rheumatic and related conditions

JAK inhibitors (JAKIs) are a new class of targeted therapy that have entered clinical practice for the treatment of immune-mediated rheumatic conditions. JAKIs can block the signaling activity of a variety of proinflammatory cytokines and therefore have the potential to mediate therapeutic benefits across a wide range of immune-mediated conditions. Several JAKIs are licensed, and many more are undergoing clinical trials. Here we provide a narrative review of the current and upcoming JAKIs for adult immune-mediated rheumatic and related conditions, with a specific focus on efficacy in rheumatoid arthritis, psoriatic arthritis, axial spondyloarthritis, psoriasis, and inflammatory bowel disease. The overall safety profile of JAKIs appears largely comparable to that of existing biologic cytokine-targeting agents, particularly, TNF inhibitors, apart from risk of herpes zoster, which is increased for JAKIs. Importantly however, unresolved safety concerns remain, particularly relating to increased venous thromboembolism.

The non-operative management of bony mallet injuries

Over a 4-year period, 218 mallet fractures in 211 adult patients were treated using a custom-made thermoplastic splint. Clinical results were collected prospectively, including the visual analogue score for pain, the range of motion and extensor lag, and the Patient Evaluation Measure (PEM). The joints were congruent in 168 and subluxed in 50. There were no differences in range of movement, extensor lag or PEM associated with articular subluxation or the size of the articular fragment. Pre-existing joint degeneration did not influence outcome. Non-surgical treatment demonstrates predictably good outcomes regardless of fragment size or subluxation in most patients and should be considered when discussing treatment for patients with bony mallet fractures.Level of evidence: III.

P052 Leflunomide and severe COVID-19 outcome: a cautionary observation from the COVID-19 Scottish Registry of Autoimmune Rheumatic Diseases (SCAR-19)

Background/Aims 

Leflunomide, a conventional disease modifying drug (csDMARD), is used in a variety of autoimmune rheumatic diseases (ARD) due to its immunomodulating, immunosuppressive and antiproliferative properties. This agent does however confer a greater infection risk and, due to its long half-life, drug washout procedures are often advised in the context of serious infections. Interestingly, Leflunomide is currently being tested as a potential therapy for COVID-19 in the general population. It is unknown whether leflunomide therapy is associated with a poor or favourable outcome among ARD patients infected with COVID-19.

Methods 

A Scottish-wide registry was rapidly developed in March 2020. Clinical characteristics and outcomes of infected cases were collated across all Scottish health boards. Eligible patients included any adult leflunomide treated ARD patients with a confirmed (clinically or PCR) diagnosis of COVID-19.

Results 

Of the 69 cases included in the registry, n = 4 were treated with leflunomide (75% female; mean age 61, SD 4.2). N = 2 were treated with combination baricitinib or hydroxychloroquine respectively, whilst n = 1 received recent corticosteroid therapy (intramuscular Kenalog). Comorbidities observed in this sub-cohort include diabetes mellitus n = 3, hypertension n = 2, cardiovascular disease n = 1, lung disease n = 1 and latent TB n = 1. At presentation, all patients (n = 4) experienced the established COVID-19 related symptom triad of dyspnoea, cough and fever and promptly developed acute respiratory syndrome. Diarrhoea was also recorded in n = 2 and constitutional upset n = 3. All patients suffered a serious COVID-19 disease outcome (defined as a requirement of invasive or non-invasive ventilation (n = 4) and/ or death (n = 2). P052 Table 1:Patient demographics, clinical characteristics and outcomesPatient 1Patient 2Patient 3Patient 4Age58635766SexFemaleFemaleMaleFemaleRheumatic diagnosisRheumatoid arthritisPsoriatic arthritisPsoriatic arthritisRheumatoid ArthritisComorbiditiesDiabetesHypertension Diabetes COPDNilIschaemic heart disease Hypertension Diabetes Latent TBClinical presentationDyspnoea Cough Fever Confusion Constitutional upsetDyspnoea Cough Fever Diarrhoea Constitutional upsetDyspnoea Cough Fever Constitutional upsetDyspnoea Cough Fever Diarrhoea Constitutional upsetAdditional csDMARD*NilNilNilHydroxychloroquinebDMARD**/ tsDMARD***BaricitinibNilNilNilSteroid therapyNilNilNilIM KenalogInvasive or non-invasive ventilationYesYesYesYesDeathNoNoYesYes* conventional disease modifying drug,**biologic disease modifying drug,***targeted synthetic disease modifying drug.

Conclusion 

Preliminary data from this Scotland-wide registry has identified only a small number of leflunomide treated ARD patients infected with COVID-19. However, it is concerning that all cases experienced a serious outcome. Given the relatively infrequent prescription of this drug, combining similar national registry data is necessary to ensure this observation is not spurious. If confirmed, leflunomide washout procedures should be encouraged among such patients when they first present with COVID-19.

Disclosure 

M. Karabayas: None. J. Brock: None. G. Fordyce: None. N. Basu: None.

O30 Variation in immunosuppressant impact on severe COVID-19 outcome: preliminary results from the COVID-19 Scottish Registry of Autoimmune Rheumatic Diseases (SCAR-19)

Background/Aims 

The novel infectious disease COVID-19 is associated with a wide spectrum of clinical severity amongst the general population. Patients with autoimmune rheumatic diseases (ARD) are more likely to experience serious COVID-19 related events, although risk factors for such outcomes have yet to be established. In particular, the risk profiles of specific ARD therapies are unknown.

Methods 

A Scottish wide registry was rapidly developed in March 2020. Clinical characteristics and outcomes of infected cases were collated across all Scottish health boards, leveraging the Scottish Systemic Vasculitis Network and Scottish Society for Rheumatology. Eligible patients included any adult ARD patients with a confirmed (clinically or PCR) diagnosis of COVID-19. Simple descriptive statistics were employed to evaluate associations between ARD therapies and a serious COVID-19 disease outcome, as defined by a requirement of invasive or non-invasive ventilation, and/or death.

Results 

A total of 69 patients (59% female; mean age 65.6, SD15.5) were recruited to the registry ,92% of which required hospitalisation. Cases were most commonly diagnosed with rheumatoid arthritis (n = 32, 46.4%) followed by spondyloarthritis (n = 19, 27.5%) and systemic vasculitis (n = 9, 13.0%). Anti-TNF therapy (n = 8, 11.6%) and methotrexate (n = 31, 44.9%) were the commonest biologic and conventional disease modifying drug (bDMARD and csDMARD) used respectively. N = 20 (29%) received background corticosteroid therapy (15.9% prednisolone >5mg, 13% prednisolone ≤5mg). A severe outcome was observed in n = 25(31.9%); n = 11 required assisted ventilation and n = 19 died. With the exception of Leflunomide, conventional and biologic DMARDs did not appear to confer a higher risk for severe outcome (table 1). Of note, anti-TNF therapy was associated with a non-serious outcome (p = 0.04) and prednisolone>5mg with a serious outcome (p = 0.08).

Conclusion 

Preliminary data from this Scotland-wide ARD COVID-19 registry evidences variation in the impact of standard ARD therapies on the severity of COVID-19 outcome. In general, background csDMARD and bDMARD use does not appear to be a risk factor for severe outcomes. However, anti-TNF therapy may confer a favourable outcome, while leflunomide and corticosteroids may have the opposite effect. Rheumatologists should be aware of these possible risk factors and continue to contribute to registries to help establish whether these putative signals are clinically relevant.

Disclosure 

M. Karabayas: None. J. Brock: None. M. Rutherford: None. G. Fordyce: None. N. Fluck: None. S. Kardash: None. L. Moran: None. R. Richmond: None. A. Tan: None. J. Sznajd: None. S. Lambie: None. M. Khalid: None. S. Else: None. C.A. Davies: None. M. Duncan: None. J. Mclaren: None. S. Duncan: None. S. Murphy5: None. F. Hasan: None. N. Basu: None.

A small proton charge radius from an electron-proton scattering experiment

Elastic electron-proton scattering (e-p) and the spectroscopy of hydrogen atoms are the two methods traditionally used to determine the proton charge radius, r_p. In 2010, a new method using muonic hydrogen atoms¹ found a substantial discrepancy compared with previous results², which became known as the 'proton radius puzzle'. Despite experimental and theoretical efforts, the puzzle remains unresolved. In fact, there is a discrepancy between the two most recent spectroscopic measurements conducted on ordinary hydrogen^3,4. Here we report on the proton charge radius experiment at Jefferson Laboratory (PRad), a high-precision e-p experiment that was established after the discrepancy was identified. We used a magnetic-spectrometer-free method along with a windowless hydrogen gas target, which overcame several limitations of previous e-p experiments and enabled measurements at very small forward-scattering angles. Our result, r_p = 0.831 ± 0.007_stat ± 0.012_syst femtometres, is smaller than the most recent high-precision e-p measurement⁵ and 2.7 standard deviations smaller than the average of all e-p experimental results⁶. The smaller r_p we have now measured supports the value found by two previous muonic hydrogen experiments^1,7. In addition, our finding agrees with the revised value (announced in 2019) for the Rydberg constant⁸-one of the most accurately evaluated fundamental constants in physics.

41. A common rheumatology referral of vague constitutional symptoms and raised inflammatory markers

Introduction

Giant cell arteritis (GCA) is an inflammatory process affecting the medium/large vessels. Initially, the symptoms are vague constitutional symptoms caused by systemic inflammation. It is a chronic, granulomatous inflammation which most classically causes headache (in the temporal/occipital region), jaw claudication, scalp tenderness and visual loss/disturbance. There is now thought to be subgroups of GCA, one of which causes inflammation without temporal involvement (LV-GCA). If left untreated, this can have serious complications including ischemia (including cerebrovascular accident) and aortic aneurysm/dissection. Diagnosis of this subgroup can be challenging and in depth scanning is often required to support this.

Case description

A 75-year-old female presents with symptomatic anaemia (dizziness and shortness of breath) with haemoglobin of 72. This improves to 110 with 2 units blood transfusion but CRP is elevated at 250-290 during admission. Initially, this is treated as a UTI but CRP does not improve. She describes vague symptoms of fatigue for “weeks” and generally feeling unwell but no specific symptoms. She denies weight loss and there are no obvious infective sounding symptoms.

She has a past medical history of left-sided lung adenocarcinoma 2 years previously which was fully treated with lobectomy, recently diagnosed as Iron deficient anaemia, vague history of seronegative rheumatoid arthritis (on no treatment and no Rheumatology review), Diverticular disease and hypothyroid. Non-smoker and lives with husband and has full independence.

Her LFT’s were deranged with mildly raised ALP/AST/ALT and there was also a description of nose bleed from the family 2 weeks prior to admission. She had a CT CAP which showed nil remarkable except trace fluid in pelvis. ESR is also raised >100 and albumin is low.

On further discussion when I reviewed her she described stiffness and pain in axial skeleton in keeping with PMR. There was no synovitis or tenderness in the joints, no rash, no sinusitis and no muscle tenderness. No features to suggest CTD or CREST. No headache or visual disturbance.

Plan was to assess ANCA, myeloma screen and arrange a PET scan for large vessel vasculitis given the CRP/ESR.

PET scan confirmed large vessel vasculitis - Marked FDG activity identified within the arterial walls of the large vessels throughout (carotids, subclavian arteries, aorta, iliacs and femoral arteries).

She was commenced on prednisolone with markedly good effect 2 weeks post treatment and is now on a reducing course of this with rheumatology follow up.

Discussion

GCA commonly affects people over the age of 50 and predominantly females. It causes inflammation in any of the proximal branches of the aorta and including the aorta itself. The diagnosis relies on the clinical history and inflammatory marker response. On occasions there will be overlap with polymyalgia rheumatica (PMR). A rational approach to diagnosis in GCA is required, based on a combination of clinical features together with relevant investigations. 

Extra-cranial GCA (or LV-GCA) is a specific subgroup of GCA which will quite often not show the typical clinical features attributed to GCA. Importantly, it is now recognised that large vessel involvement is very common in all GCA patients and can lead to marked complications. 

PET-CT scanning is extremely useful in diagnosing LV-GCA but delays occur in diagnosis secondary to waiting times and resources to carry out the scan and there is some information which suggests that these scans may lead to over-estimation of inflammation. Other imaging modalities include USS of some of the proximal branches of the aorta and CT/MRI angiography.

The concern of missing this diagnosis can be severe including ischaemic events, aneurysm of the aorta and possible CVA leading to significant morbidity and mortality. It is now wondered whether some of the patients who develop these complications could have underlying LVV.

Differential diagnoses must also be sought when making a diagnosis of LV-GCA including multiple myeloma, endocarditis/infections, other Rheumatological conditions and atherosclerosis. This can again lead to uncertainties when making a diagnosis.

It is important to commence steroid therapy at the earliest opportunity but awareness is required surrounding investigations and organising this as steroids can mask inflammation. Therefore it is important to correctly make the diagnosis with certainty and obtain a scan to prove LV-GCA as soon as possible.

Key learning points

One area of difficulty remains on the course of treatment for the extra-cranial GCA subgroup (or LV-GCA) and at present this is treated in the same way as cranial GCA. However, obviously with the advancements in tocilizumab as a steroid sparing therapy in cranial GCA this leads to a difficulty in understanding its role for the LV-GCA. Given the issue of not understanding biologics role in LV-GCA, this causes difficulty in utilising steroid sparing agents.

There is no diagnostic criteria for GCA but there is classification criteria which remains useful for the diagnosis of cranial GCA; however, it is less helpful for LV-GCA and therefore a large amount of the diagnosis depends on clinical judgement and imaging, as described above, to clarify the diagnosis. The importance of making a correct diagnosis is key given this will commit someone to a very long course of steroid therapy which obviously can lead to a great deal of side effects long term.

In addition, imaging modalities are now more plentiful for diagnosis and there is a large amount of information on this in the EULAR and BSR guidelines. Key areas of discussion still lie in which imaging techniques are best to use and the roles of using imaging in monitoring disease activity is still unknown.

Awareness is improving around this disease as there is obviously huge links to high morbidity and mortality complications including, as mentioned, stroke, ischaemic symptoms/claudication due to narrowing of the vessels from inflammation and aortic aneurysm/dissections too. Diagnosing all subgroups of GCA early is key to preventing these outcomes. In addition to this, it is important to obtain the correct diagnosis to prevent needless use of steroids and from missing potential differential diagnoses.

Conflicts of interest

The authors have declared no conflicts of interest.

First Measurements of the Double-Polarization Observables F, P, and H in ω Photoproduction off Transversely Polarized Protons in the N^{*} Resonance Region

First measurements of double-polarization observables in ω photoproduction off the proton are presented using transverse target polarization and data from the CEBAF Large Acceptance Spectrometer (CLAS) FROST experiment at Jefferson Lab. The beam-target asymmetry F has been measured using circularly polarized, tagged photons in the energy range 1200-2700 MeV, and the beam-target asymmetries H and P have been measured using linearly polarized, tagged photons in the energy range 1200-2000 MeV. These measurements significantly increase the database on polarization observables. The results are included in two partial-wave analyses and reveal significant contributions from several nucleon (N^{*}) resonances. In particular, contributions from new N^{*} resonances listed in the Review of Particle Properties are observed, which aid in reaching the goal of mapping out the nucleon resonance spectrum.

Delayed Profunda Femoris Artery Bleeding After Intramedullary Nailing of an Unstable Intertrochanteric Fracture: A Case Report

CASE

A 75-year-old man underwent intramedullary nailing for an unstable intertrochanteric fracture of the left hip. After surgery and postoperative recovery, he was transferred to a rehabilitation ward. He was able to mobilize at 2 days postoperatively; at 2 weeks postoperatively, he developed the sudden onset of tachycardia, hypotension, and a large hematoma on the left thigh. Following immediate resuscitation, a computed tomography (CT) angiogram demonstrated a bleed from a branch of the profunda femoris artery. The 3-dimensional CT reconstruction implicated the displaced lesser trochanter osseous fragment as the cause of the hemorrhage.

CONCLUSION

Surgeons should be aware of this rare complication and the possible etiology of fracture displacement as the cause of a delayed-onset bleed after intramedullary nailing, and they should also be cognizant of the subsequent optimal management.

Abstract PD6-09: The immune microenvironment in hormone receptor-positive breast cancer patients and relationship to treatment outcome following preoperative chemotherapy plus bevacizumab

Background: Hormone receptor-positive (HR+) tumors have fewer tumor-infiltrating lymphocytes (TILs) and lower response rates to immune checkpoint inhibitors (ICI), either as single agents or in combination with chemotherapy, than triple negative cancers. However, some HR+ cancers do respond to ICI and biomarkers that accurately reflect the immune microenvironment may help guide the use of ICI therapy. Prior evidence suggests that macrophage-related immune pathways may be relevant to the pathophysiology of HR+ BC.

Methods: HR+/HER2- patients were identified from a prospective trial of preoperative bevacizumab (preop bev) followed by bev with adriamycin/cyclophosphamide/paclitaxel dose-dense chemotherapy (chemo). Tumor samples were collected at diagnosis and surgery (pre-tx and post-tx), and PD-L1 expression (by immunohistochemistry), TILs, and Nanostring PanCancer Immune Profiling Panel were evaluated on both pre-tx and post-tx specimens. Pre-tx whole transcriptome sequencing was performed. Pathologic response at surgery was centrally assessed by Miller-Payne (MP) and residual cancer burden (RCB) scores. An immune score was calculated for each pre-tx specimen by integrating 10 published immune signatures. Immune cell subsets were inferred from bulk transcriptional data using CIBERSORT and immune cell-specific signatures from MSigDB.

Results: 55 patients who received trial therapy and had at least 1 evaluable specimen were included for analysis. Pre-tx TILs and tumor PD-L1 (tPD-L1) scores are shown in the table. 18% of pre-tx tumors had “high” (≥10%) TILs and “high” TILs were associated with significantly higher immune signature score (p=0.004). Immune score correlated highly with proportion of CIBERSORT anti-tumor M1 macrophages as well as CD8 T-cell signatures (r&gt;0.65 and p&lt;0.001). Higher pre-tx TILs, tPD-L1, or immune score were each significantly associated with more favorable RCB and MP in unadjusted analyses (all Spearman p&lt;0.01 for pathologic markers; ANOVA p&lt;0.04 for immune score). After adjustment for age and tumor grade, higher pre-tx TILs and tPD-L1 were associated with favorable RCB (p&lt;0.01 for both), and higher pre-tx tPD-L1 correlated with favorable MP (p=0.03). Pathologic complete response occurred in 4 pts; all 4 had high pre-tx TILs, pre-tx tPD-L1, or both. Among patients with residual disease, large changes (&gt;5%) in TILs or tPD-L1 from pre-tx to post-tx were rare: 2 pts each had large changes in TIL or tPD-L1 score (N=38/N=31 pairs, respectively).

Conclusions: High levels of tumor-lymphocyte interaction were seen in only a minority of untreated HR+ breast tumors, and did not typically change with chemo plus bev. An immune score derived from bulk RNAseq correlated with histological observations in these specimens. Nonetheless, TILs, tPD-L1, and signature-derived immune score were significantly associated with pathologic response to preop treatment in HR+ disease. Early data suggest that the role of M1 macrophages in HR+ tumors warrants further investigation.

ScoreTILs (N=50 evaluable)Tumor PD-L1 (N=51)0%0 pts (0%)28 pts (55%)&gt;0-5% (low)19 (38%)18 (35%)&gt;5-10% (intermediate)22 (44%)3 (6%)&gt;10% (high)9 (18%)2 (4%)

Citation Format: Waks AG, Stover DG, Barry W, Dillon D, Gjini E, Rodig SJ, Brock J, Baltay M, Savoie J, Winer EP, Krop I, Tolaney SM. The immune microenvironment in hormone receptor-positive breast cancer patients and relationship to treatment outcome following preoperative chemotherapy plus bevacizumab [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr PD6-09.

Abstract OT3-05-01: TBCRC 039: Phase II study of combination ruxolitinib (INCB018424) with preoperative chemotherapy for triple negative inflammatory breast cancer

Background: Stage III triple negative(TN) inflammatory breast cancer(IBC) is associated with a poor prognosis evidenced by a 15 month(mo) median disease free survival(DFS) and overall survival(OS) of 34 mo. The substantial incidence of developing distant metastasis may be due to the prevalence of cancer cells with stem cell-like features (e.g. CD44+/CD24-) in TNIBC. The transcriptional pathway JAK2/STAT3 is associated with the survival of CD44+/CD24- cells, and preclinical data demonstrates overexpression of activated STAT3(pSTAT3) in &gt; 95% of TNIBC. Preclinical studies have shown that ruxolitinib (Incyte®Corporation), an approved JAK1/JAK2 inhibitor, suppresses pSTAT3 in IBC patient derived xenograft models, and when combined with paclitaxel, results in a synergistic reduction in tumor weight. Given the lack of a known therapeutic target in TNIBC, this preoperative proof of principle study exploits the survival mechanism of CD44+/CD24- stem cells prevalent in this disease, by combining ruxolitinib(Rux) with paclitaxel(T) followed by doxorubicin/cyclophosphamide(AC).

Methods: Up to 64 pts with newly diagnosed stage III TNIBC (cT4d, any N, M0) are eligible if they have adequate organ function and are willing to undergo 2 research biopsies(rbx) of the affected breast. Following baseline rbx, pts are randomized to a 7 day(d) run-in phase of Rux vs Rux(15 mg bid) + T(80mg/m2/wkx1). A 2nd rbx is obtained after the run-in phase. Pts randomized to RuxT continue to receive a total of Tx12 wks+Rux. Pts randomized to Rux alone, are re-randomized to receive Tx12 wks+Rux vs Tx12wks alone. Following T, all pts receive AC (A-60mg/m2,C-600mg/m2) every 14d x 4. Pts proceed to modified radical mastectomy (MRM) followed by chest wall/regional lymph nodes radiation therapy.

Correlatives: To assess the effect of JAK inhibition with Rux on pSTAT3 and STAT3 related gene expression, molecular and genomic markers (e.g. RNA-seq, ChIPseq, FISH) will be determined in each rbx and residual tumor at MRM. The relative frequency and topology of CD44+/CD24- cell population and pSTAT3 expression by IHC will also be assessed in these tumor specimens. IL-6 and CRP plasma concentrations will be measured at baseline, prior to T and AC and prior to MRM.

Statistics: The primary endpoint is change in markers of JAK/STAT inhibition. If the proportion of rbx exhibit a biologic response to Rux alone (i.e. change from pSTAT3 expression to pSTAT3 negative) is &lt;10%, then Rux alone is minimally effective on JAK inhibition vs alternative hypothesis that Rux inhibits JAK if the proportion of biologic response is ≥33%. If ≥5/25 rbx treated with Rux alone have a biologic response then the hypothesis that biologic response is ≤10% is rejected with an error rate of 0.098 (target 0.10). If ≤4/25 rbx have a biologic response then the hypothesis that biologic response is ≥33% is rejected with an error rate of 0.05 (target 0.10). Biologic response of rbx with Rux alone will also be compared with the proportion of biologic response to RuxT (33% vs. 66% based upon presumed synergy with RuxT). Secondary endpoints are clinical: pathologic complete response in breast/lymph nodes, Residual Cancer Burden, DFS and OS. Clinical Trial Information: NCT02876302.

Citation Format: Overmoyer B, Regan M, Polyak K, Brock J, Van Poznak C, King T, Haddad T, Stearns V, Hwang S, Winer E. TBCRC 039: Phase II study of combination ruxolitinib (INCB018424) with preoperative chemotherapy for triple negative inflammatory breast cancer [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr OT3-05-01.

Measurement of the Q^{2} Dependence of the Deuteron Spin Structure Function g_{1} and its Moments at Low Q^{2} with CLAS

We measured the g_{1} spin structure function of the deuteron at low Q^{2}, where QCD can be approximated with chiral perturbation theory (χPT). The data cover the resonance region, up to an invariant mass of W≈1.9  GeV. The generalized Gerasimov-Drell-Hearn sum, the moment Γ_{1}^{d} and the spin polarizability γ_{0}^{d} are precisely determined down to a minimum Q^{2} of 0.02  GeV^{2} for the first time, about 2.5 times lower than that of previous data. We compare them to several χPT calculations and models. These results are the first in a program of benchmark measurements of polarization observables in the χPT domain.

The evaluation of tumor-infiltrating lymphocytes (TILs) in breast cancer: recommendations by an International TILs Working Group 2014

BACKGROUND

The morphological evaluation of tumor-infiltrating lymphocytes (TILs) in breast cancer (BC) is gaining momentum as evidence strengthens for the clinical relevance of this immunological biomarker. Accumulating evidence suggests that the extent of lymphocytic infiltration in tumor tissue can be assessed as a major parameter by evaluation of hematoxylin and eosin (H&E)-stained tumor sections. TILs have been shown to provide prognostic and potentially predictive value, particularly in triple-negative and human epidermal growth factor receptor 2-overexpressing BC.

DESIGN

A standardized methodology for evaluating TILs is now needed as a prerequisite for integrating this parameter in standard histopathological practice, in a research setting as well as in clinical trials. This article reviews current data on the clinical validity and utility of TILs in BC in an effort to foster better knowledge and insight in this rapidly evolving field, and to develop a standardized methodology for visual assessment on H&E sections, acknowledging the future potential of molecular/multiplexed approaches.

CONCLUSIONS

The methodology provided is sufficiently detailed to offer a uniformly applied, pragmatic starting point and improve consistency and reproducibility in the measurement of TILs for future studies.

Longitudinal target-spin asymmetries for deeply virtual compton scattering

A measurement of the electroproduction of photons off protons in the deeply inelastic regime was performed at Jefferson Lab using a nearly 6 GeV electron beam, a longitudinally polarized proton target, and the CEBAF Large Acceptance Spectrometer. Target-spin asymmetries for ep→e^{'}p^{'}γ events, which arise from the interference of the deeply virtual Compton scattering and the Bethe-Heitler processes, were extracted over the widest kinematics in Q^{2}, x_{B}, t, and ϕ, for 166 four-dimensional bins. In the framework of generalized parton distributions, at leading twist the t dependence of these asymmetries provides insight into the spatial distribution of the axial charge of the proton, which appears to be concentrated in its center. These results also bring important and necessary constraints for the existing parametrizations of chiral-even generalized parton distributions.

The evaluation of tumor-infiltrating lymphocytes (TILs) in breast cancer: recommendations by an International TILs Working Group 2014

BACKGROUND

The morphological evaluation of tumor-infiltrating lymphocytes (TILs) in breast cancer (BC) is gaining momentum as evidence strengthens for the clinical relevance of this immunological biomarker. Accumulating evidence suggests that the extent of lymphocytic infiltration in tumor tissue can be assessed as a major parameter by evaluation of hematoxylin and eosin (H&E)-stained tumor sections. TILs have been shown to provide prognostic and potentially predictive value, particularly in triple-negative and human epidermal growth factor receptor 2-overexpressing BC.

DESIGN

A standardized methodology for evaluating TILs is now needed as a prerequisite for integrating this parameter in standard histopathological practice, in a research setting as well as in clinical trials. This article reviews current data on the clinical validity and utility of TILs in BC in an effort to foster better knowledge and insight in this rapidly evolving field, and to develop a standardized methodology for visual assessment on H&E sections, acknowledging the future potential of molecular/multiplexed approaches.

CONCLUSIONS

The methodology provided is sufficiently detailed to offer a uniformly applied, pragmatic starting point and improve consistency and reproducibility in the measurement of TILs for future studies.

Fast reconstruction of 3D volumes from 2D CT projection data with GPUs

BACKGROUND

Biomedical image reconstruction applications require producing high fidelity images in or close to real-time. We have implemented reconstruction of three dimensional conebeam computed tomography(CBCT) with two dimensional projections. The algorithm takes slices of the target, weights and filters them to backproject the data, then creates the final 3D volume. We have implemented the algorithm using several hardware and software approaches and taken advantage of different types of parallelism in modern processors. The two hardware platforms used are a Central Processing Unit (CPU) and a heterogeneous system with a combination of CPU and GPU. On the CPU we implement serial MATLAB, parallel MATLAB, C and parallel C with OpenMP extensions. These codes are compared against the heterogeneous versions written in CUDA-C and OpenCL.

FINDINGS

Our results show that GPUs are particularly well suited to accelerating CBCT. Relative performance was evaluated on a mathematical phantom as well as on mouse data. Speedups of up to 200x are observed by using an AMD GPU compared to a parallel version in C with OpenMP constructs.

CONCLUSIONS

In this paper, we have implemented the Feldkamp-Davis-Kress algorithm, compatible with Fessler's image reconstruction toolbox and tested it on different hardware platforms including CPU and a combination of CPU and GPU. Both NVIDIA and AMD GPUs have been used for performance evaluation. GPUs provide significant speedup over the parallel CPU version.

Prevalence of Francisella noatunensis subsp. orientalis in cultured tilapia on the island of Oahu, Hawaii

Francisellosis is an emergent disease in cultured and wild aquatic animals. The causative agent, Francisella noatunensis subsp. orientalis (Fno), is a gram-negative bacterium recognized as one of the most virulent pathogens of warmwater fish. The main objective of this project was to investigate the prevalence of Fno in cultured tilapia (specifically, Mozambique Tilapia Oreochromis mossambicus, Koilapia [also known as Wami Tilapia] O. hornorum, Blue Tilapia O. aureus, and Nile Tilapia O. niloticus hybrids) on the island of Oahu, Hawaii, using conventional and real-time PCR assays followed by statistical modeling to compare the different diagnostic methods and identify potential risk factors. During 2010 and 2012, 827 fish were collected from different geographical locations throughout the island of Oahu. Upon collection of fish, the water temperature in the rearing system and the length of individual fish were measured. Extraction of DNA from different tissues collected aseptically during necropsy served as a template for molecular diagnosis. High correlation between both molecular methods was observed. Moreover, the bacterium was isolated from infected tilapia on selective media and confirmed to be Fno utilizing a species-specific Taqman-based real-time PCR assay. Although a direct comparison of the prevalence of Fno between the different geographical areas was not possible, the results indicate a high prevalence of Fno DNA in cultured tilapia throughout the farm sites located on Oahu. Of the different tilapia species and hybrids currently cultured in Hawaii, Mozambique Tilapia were more susceptible to infection than Koilapia. Water temperature in the rearing systems and fish size also had a strong effect on the predicted level of infection, with fish held at lower temperatures and smaller fish being more susceptible to piscine francisellosis.

The effect of temporal impulse response on experimental reduction of photon scatter in time-resolved diffuse optical tomography

New fast detector technology has driven significant renewed interest in time-resolved measurement of early photons in improving imaging resolution in diffuse optical tomography and fluorescence mediated tomography in recent years. In practice, selection of early photons results in significantly narrower instrument photon density sensitivity functions (PDSFs) than the continuous wave case, resulting in a better conditioned reconstruction problem. In this work, we studied the quantitative impact of the instrument temporal impulse response function (TIRF) on experimental PDSFs in tissue mimicking optical phantoms. We used a multimode fiber dispersion method to vary the system TIRF over a range of representative literature values. Substantial disagreement in PDSF width--by up to 40%--was observed between experimental measurements and Monte Carlo (MC) models of photon propagation over the range of TIRFs studied. On average, PDSFs were broadened by about 0.3 mm at the center plane of the 2 cm wide imaging chamber per 100 ps of the instrument TIRF at early times. Further, this broadening was comparable on both the source and detector sides. Results were confirmed by convolution of instrument TIRFs with MC simulations. These data also underscore the importance of correcting imaging PDSFs for the instrument TIRF when performing tomographic image reconstruction to ensure accurate data-model agreement.