Advanced quantitative evaluation of PET systems using the ACR phantom and NiftyPET software

PURPOSE

A novel phantom-imaging platform, a set of software tools, for automated and high-precision imaging of the American College of Radiology (ACR) positron emission tomography (PET) phantom for PET/magnetic resonance (PET/MR) and PET/computed tomography (PET/CT) systems is proposed.

METHODS

The key feature of this platform is the vector graphics design that facilitates the automated measurement of the knife-edge response function and hence image resolution, using composite volume of interest templates in a 0.5 mm resolution grid applied to all inserts of the phantom. Furthermore, the proposed platform enables the generation of an accurate μ $\mu$ -map for PET/MR systems with a robust alignment based on two-stage image registration using specifically designed PET templates. The proposed platform is based on the open-source NiftyPET software package used to generate multiple list-mode data bootstrap realizations and image reconstructions to determine the precision of the two-stage registration and any image-derived statistics. For all the analyses, iterative image reconstruction was employed with and without modeled shift-invariant point spread function and with varying iterations of the ordered subsets expectation maximization (OSEM) algorithm. The impact of the activity outside the field of view (FOV) was assessed using two acquisitions of 30 min each, with and without the activity outside the FOV.

RESULTS

The utility of the platform has been demonstrated by providing a standard and an advanced phantom analysis including the estimation of spatial resolution using all cylindrical inserts. In the imaging planes close to the edge of the axial FOV, we observed deterioration in the quantitative accuracy, reduced resolution (FWHM increased by 1-2 mm), reduced contrast, and background uniformity due to the activity outside the FOV. Although it slows convergence, the PSF reconstruction had a positive impact on resolution and contrast recovery, but the degree of improvement depended on the regions. The uncertainty analysis based on bootstrap resampling of raw PET data indicated high precision of the two-stage registration.

CONCLUSIONS

We demonstrated that phantom imaging using the proposed methodology with the metric of spatial resolution and multiple bootstrap realizations may be helpful in more accurate evaluation of PET systems as well as in facilitating fine tuning for optimal imaging parameters in PET/MR and PET/CT clinical research studies.

Real world evaluation of artificial intelligence echocardiography image guidance and acquisition with novice scanners in multiple clinical settings

Funding Acknowledgements

Type of funding sources: Private company. Main funding source(s): Caption Health, US

OnBehalf

Beacon Hospital Research Institute

Background

Cardiac echocardiographic scanning requires significant training and experience. The FDA approved Caption Echocardiography system uses a deep learning artificial intelligence software that guides novice scanners to optimal position and then automatically acquires the highest quality image. Further advances to this novel technology have allowed for immediate calculation of left ventricular ejection fraction directly from these images.

Methods

Following only brief training, we sought to evaluate study quality by novice scanners in four clinical settings, both acute and ambulatory – the Emergency Department, Intensive Care Unit, Heart Failure clinic, and the Oncology Day Unit. 120 patients (30 per clinical area) were recruited and underwent 2 echo scans – one by a novice scanner using the Caption AI system, and one by an expert scanner using the same ultrasound system but without AI guidance. Both studies were evaluated blindly and independently side by side by 3 accredited experts judging diagnostic quality. ‘AutoEF’ measurements were compared with expert scanners measurements by Simpson’s biplane technique.

Results

120 patients with mean age 62.04 years old (range 18 – 92)  were enrolled, consisting of 30 from each clinical area. 8 novice scanners – nursing staff and junior doctors – scanned 15 patients each, allowing their first 3 cases to be excluded. 75% of patients were male. BMI ranged from 18 – 37 with mean 27.48. Image quality allowed left ventricular function to be sufficiently captured in 97.5% of studies, right ventricular function in 95% and outrule of pericardial effusion in 97.5%. ‘AutoEF’ was determined in 88.3% of studies and matched the expert measurement in 84% of cases. Blinded expert assessment found that 60% of Caption studies were of equal or better quality than the experienced sonographer scan.

Conclusion

The Caption AI technology safely allows novice users to provide efficient and accurate point of care echo in differing clinical settings to a standard comparable to expert scanners, and automatically determines left ventricular ejection fraction.

Towards nationally curated data archives for clinical radiology image analysis at scale: Learnings from national data collection in response to a pandemic

The prevalence of the coronavirus SARS-CoV-2 disease has resulted in the unprecedented collection of health data to support research. Historically, coordinating the collation of such datasets on a national scale has been challenging to execute for several reasons, including issues with data privacy, the lack of data reporting standards, interoperable technologies, and distribution methods. The coronavirus SARS-CoV-2 disease pandemic has highlighted the importance of collaboration between government bodies, healthcare institutions, academic researchers and commercial companies in overcoming these issues during times of urgency. The National COVID-19 Chest Imaging Database, led by NHSX, British Society of Thoracic Imaging, Royal Surrey NHS Foundation Trust and Faculty, is an example of such a national initiative. Here, we summarise the experiences and challenges of setting up the National COVID-19 Chest Imaging Database, and the implications for future ambitions of national data curation in medical imaging to advance the safe adoption of artificial intelligence in healthcare.

Survival Outcome with Routine Clinical Use of 82Rb PET/CT Myocardial Blood Flow (MBF) Quantification

Funding Acknowledgements

Type of funding sources: Public Institution(s). Main funding source(s): NIHR Biomedical Research Centre, University College London Hospitals

Background

The prognostic value of 82Rb PET/CT derived myocardial blood flow (MBF) is increasingly recognised in both general and specific cardiovascular populations.

Purpose

This study investigates the prognostic potential of MBF in a large cohort of patients undergoing routine 82Rb PET/CT examination.

Methods

1148 consecutive patients (687 males, mean age 64 +/- 12 years) whom had been referred for 82Rb PET/CT examination in a single centre were included in this study.  All patients completed a stress 82Rb PET/CT with adenosine infusion, paired with a rest study.  Dynamic PET acquisitions were performed in both. Cardiovascular risk factors were documented as per clinical routine. Images were checked for quality and analysed using a proprietary software by an experienced operator to derive MBF parameters.  Overall survival was recorded following the study.

Results

Median follow-up period was 71 +/- 28 months.  Mean survival was 121 (95% CI: 118-124) months. On univariate analysis, global myocardial flow reserve <1.77 was associated with a higher all-cause mortality (p < 0.001). Other parameters including higher age (> =76 years), lower BMI (<21), qualitative abnormality on the myocardial perfusion scan (MPS), low hyperaemic ejection fraction on the gated studies (stress < 37 and rest < 34). Patients being on cardiac glycosides and diuretics were also significant predictor of poor prognosis (p < 0.001) on univariate analysis, presumably reflecting underlying arrhythmia and heart failure. A multivariate Cox regression analysis (step-wise Forward Wald), comprising of the above significant univariate markers, highlighted global myocardial flow reserve (HR: 2.6, 95%CI: 1.8-3.6, p < 0.001), age (HR: 2.8, 95%CI: 2.0-3.9, p < 0.001),, BMI (HR: 2.7, 95%CI: 1.7-4.1, p < 0.001),, ejection fraction (stress - HR: 3.3, 95%CI: 2.3-4.8, p < 0.001), MPS (HR: 1.5, 95%CI: 1.1-2.1, p = 0.024), and patients on diuretics (HR: 1.8, 95%CI: 1.2-2.5, p = 0.003) were independent predictors of overall survival (overall model: p < 0.001)

Discussion

We show that high volume routinely derived MBF in patients undergoing 82Rb PET/CT is a strong predictor of mortality and independent of other risk factors. This has important clinical implication for measuring not only interventional treatment but also measuring the effect of lifestyle and medical strategies.

Letter to the Editor in response to the Position statement and best practice recommendations on the imaging use of ultrasound from the European Society of Radiology ultrasound subcommittee

This letter to the editor is in response to the consensus statement from the Ultrasound Subcommittee of the European Society of Radiology, the European Union of Medical Specialists (UEMS) Section of Radiology, and the European Federation of Societies for Ultrasound in Medicine and Biology. It highlights the role of the non-medical sonographer in the UK and the evidence underpinning this safe and effective practice.

Discovery of pre-therapy 2-deoxy-2-18F-fluoro-D-glucose positron emission tomography-based radiomics classifiers of survival outcome in non-small-cell lung cancer patients

PURPOSE

The aim of this multi-center study was to discover and validate radiomics classifiers as image-derived biomarkers for risk stratification of non-small-cell lung cancer (NSCLC).

PATIENTS AND METHODS

Pre-therapy PET scans from a total of 358 Stage I-III NSCLC patients scheduled for radiotherapy/chemo-radiotherapy acquired between October 2008 and December 2013 were included in this seven-institution study. A semi-automatic threshold method was used to segment the primary tumors. Radiomics predictive classifiers were derived from a training set of 133 scans using TexLAB v2. Least absolute shrinkage and selection operator (LASSO) regression analysis was used for data dimension reduction and radiomics feature vector (FV) discovery. Multivariable analysis was performed to establish the relationship between FV, stage and overall survival (OS). Performance of the optimal FV was tested in an independent validation set of 204 patients, and a further independent set of 21 (TESTI) patients.

RESULTS

Of 358 patients, 249 died within the follow-up period [median 22 (range 0-85) months]. From each primary tumor, 665 three-dimensional radiomics features from each of seven gray levels were extracted. The most predictive feature vector discovered (FVX) was independent of known prognostic factors, such as stage and tumor volume, and of interest to multi-center studies, invariant to the type of PET/CT manufacturer. Using the median cut-off, FVX predicted a 14-month survival difference in the validation cohort (N = 204, p = 0.00465; HR = 1.61, 95% CI 1.16-2.24). In the TESTI cohort, a smaller cohort that presented with unusually poor survival of stage I cancers, FVX correctly indicated a lack of survival difference (N = 21, p = 0.501). In contrast to the radiomics classifier, clinically routine PET variables including SUVmax, SUVmean and SUVpeak lacked any prognostic information.

CONCLUSION

PET-based radiomics classifiers derived from routine pre-treatment imaging possess intrinsic prognostic information for risk stratification of NSCLC patients to radiotherapy/chemo-radiotherapy.

Critical care usage after major gastrointestinal and liver surgery: a prospective, multicentre observational study

BACKGROUND

Patient selection for critical care admission must balance patient safety with optimal resource allocation. This study aimed to determine the relationship between critical care admission, and postoperative mortality after abdominal surgery.

METHODS

This prespecified secondary analysis of a multicentre, prospective, observational study included consecutive patients enrolled in the DISCOVER study from UK and Republic of Ireland undergoing major gastrointestinal and liver surgery between October and December 2014. The primary outcome was 30-day mortality. Multivariate logistic regression was used to explore associations between critical care admission (planned and unplanned) and mortality, and inter-centre variation in critical care admission after emergency laparotomy.

RESULTS

Of 4529 patients included, 37.8% (n=1713) underwent planned critical care admissions from theatre. Some 3.1% (n=86/2816) admitted to ward-level care subsequently underwent unplanned critical care admission. Overall 30-day mortality was 2.9% (n=133/4519), and the risk-adjusted association between 30-day mortality and critical care admission was higher in unplanned [odds ratio (OR): 8.65, 95% confidence interval (CI): 3.51-19.97) than planned admissions (OR: 2.32, 95% CI: 1.43-3.85). Some 26.7% of patients (n=1210/4529) underwent emergency laparotomies. After adjustment, 49.3% (95% CI: 46.8-51.9%, P<0.001) were predicted to have planned critical care admissions, with 7% (n=10/145) of centres outside the 95% CI.

CONCLUSIONS

After risk adjustment, no 30-day survival benefit was identified for either planned or unplanned postoperative admissions to critical care within this cohort. This likely represents appropriate admission of the highest-risk patients. Planned admissions in selected, intermediate-risk patients may present a strategy to mitigate the risk of unplanned admission. Substantial inter-centre variation exists in planned critical care admissions after emergency laparotomies.

A virtual patient model for mechanical ventilation

BACKGROUND AND OBJECTIVES

Mechanical ventilation (MV) is a primary therapy for patients with acute respiratory failure. However, poorly selected ventilator settings can cause further lung damage due to heterogeneity of healthy and damaged alveoli. Varying positive-end-expiratory-pressure (PEEP) to a point of minimum elastance is a lung protective ventilator strategy. However, even low levels of PEEP can lead to ventilator induced lung injury for individuals with highly inflamed pulmonary tissue. Hence, models that could accurately predict peak inspiratory pressures after changes to PEEP could improve clinician confidence in attempting potentially beneficial treatment strategies.

METHODS

This study develops and validates a physiologically relevant respiratory model that captures elastance and resistance via basis functions within a well-validated single compartment lung model. The model can be personalised using information available at a low PEEP to predict lung mechanics at a higher PEEP. Proof of concept validation is undertaken with data from four patients and eight recruitment manoeuvre arms.

RESULTS

Results show low error when predicting upwards over the clinically relevant pressure range, with the model able to predict peak inspiratory pressure with less than 10% error over 90% of the range of PEEP changes up to 12 cmH₂O.

CONCLUSIONS

The results provide an in-silico model-based means of predicting clinically relevant responses to changes in MV therapy, which is the foundation of a first virtual patient for MV.

Comparative effects of in ovo versus subcutaneous administration of the Marek's disease vaccine and pre-placement holding time on the post-hatch performance of Ross 708 broilers1,2,3

Effects of 2 types of methods of administration (moa; in ovo or s.c.) of the Marek's disease (MD) vaccine and 4 and 18 h pre-placement holding times (pht) on the performance of male broilers through 48 d of age were investigated. Ross 708 broiler hatching eggs (3,900) were either in ovo-vaccinated at 18 d of incubation or chicks from eggs that were not in ovo-injected were vaccinated s.c. at hatch, and chicks from each moa group were held for one of the 2 pht. In ovo injections (50 μL) were delivered by a commercial multi-egg injector and s.c. injections (0.2 mL) were delivered by an automatic pneumatic s.c. injector. Sixteen birds were assigned to each of 15 replicate floor pens belonging to each of the 4 moa and pht combination groups. Mortality and BW gain were determined at weekly intervals, and feed consumption and conversion were determined in the zero to 14, 14 to 28, 28 to 42, and 42 to 48 d age intervals. No interactive effects between moa and pht were observed for any variable, and mortality was not significantly affected by moa or pht. The 14 to 28 d feed consumption and 14 to 21 d BW gain of s.c.-vaccinated birds were lower than that of in ovo-vaccinated birds, and the increase in pht from 4 to 18 h decreased feed consumption through 28 d post hatch and BW gain through 35 d post hatch. Overall, the performances of male Ross 708 broilers through 48 d of age in response to in ovo and s.c. injections of the MD vaccine were comparable, and delays in hatchling placement should be less that 18 h in duration. Furthermore, despite the decrease in BW gain through 35 d associated with the reduction in feed consumption through 28 d in response to the 14 h increase in pht, in ovo injection did not exacerbate the effect of the increase in pht.

Do drugs offering only PFS maintain quality of life sufficiently from a patient's perspective? Results from AVALPROFS (Assessing the 'VALue' to patients of PROgression Free Survival) study

Purpose

Trials of novel drugs used in advanced disease often show only progression-free survival or modest overall survival benefits. Hypothetical studies suggest that stabilisation of metastatic disease and/or symptom burden are worth treatment-related side effects. We examined this premise contemporaneously using qualitative and quantitative methods.

Methods

Patients with metastatic cancers expected to live > 6 months and prescribed drugs aimed at cancer control were interviewed: at baseline, at 6 weeks, at progression, and if treatment was stopped for toxicity. They also completed Functional Assessment of Cancer Therapy (FACT-G) plus Anti-Angiogenesis (AA) subscale questionnaires at baseline then monthly for 6 months.

Results

Ninety out of 120 (75%) eligible patients participated: 41 (45%) remained on study for 6 months, 36 progressed or died, 4 had treatment breaks, and 9 withdrew due to toxicity. By 6 weeks, 66/69 (96%) patients were experiencing side effects which impacted their activities. Low QoL scores at baseline did not predict a higher risk of death or dropout. At 6-week interviews, as the side effect severity increased, patients were significantly less inclined to view the benefit of cancer control as worthwhile (X² = 50.7, P < 0.001). Emotional well-being initially improved from baseline by 10 weeks, then gradually returned to baseline levels.

Conclusion

Maintaining QoL is vital to most patients with advanced cancer so minimising treatment-related side effects is essential. As side effect severity increased, drugs that controlled cancer for short periods were not viewed as worthwhile. Patients need to have the therapeutic aims of further anti-cancer treatment explained honestly and sensitively.

Electronic supplementary material

The online version of this article (10.1007/s00520-018-4273-3) contains supplementary material, which is available to authorized users.

Comparative effects of in ovo versus subcutaneous administration of the Marek's disease vaccine and pre-placement holding time on the processing yield of Ross 708 broilers

Effects of the in ovo (i.o.) or subcutaneous (s.c.) method of administration (moa) of the Marek's disease (MD) vaccine and 4 or 18 h pre-placement holding time (pht) on the processing yield of male broilers through 49 d of age (doa) were investigated. Ross 708 broiler hatching eggs (3,900) were either i.o.-vaccinated at 18 d of incubation or chicks from eggs that were not i.o.-vaccinated were s.c.-vaccinated at hatch. The i.o. injections (50 μL) were delivered by a commercial multi-egg injector and s.c. injections (200 μL) were delivered by an automatic pneumatic s.c. injector. The pht was imposed on chicks after vaccination. Sixteen birds were initially assigned to each of 15 replicate floor pens belonging to each of the moa and pht combination groups and were grown out through 48 doa. At 48 doa, 6 birds were randomly selected from each replicate pen and were weighed and fasted for 16 h before being processed. At 49 doa, whole carcass, fat pad, breast muscle, and tenders muscles weights were recorded. Whole carcass weight as a percentage of live BW, and fat pad, breast muscle, and tenders muscles weights as percentages of both live and whole carcass weights were calculated. Upon subjection of the data to a 2 × 2 factorial analysis, only a main effect due to moa was observed for tenders muscles weight as a percentage of live and whole carcass weights. Tenders muscles weight as a percentage of both live (P ≤ 0.010) and whole carcass (P ≤ 0.004) weight was higher in birds hatched from eggs that received i.o. rather than s.c. vaccinations. In conclusion, in comparison to s.c. vaccination, i.o. vaccination increased relative tenders weight yield, whether or not broilers were held for 4 or 18 h prior to placement. Therefore, with regard to broiler processing yield, i.o. and s.c. vaccinations were safe for the administration of the MD vaccine, with i.o. vaccination displaying a slight potential advantage.

Centralization of Services: Standard Setting and Outcomes

Objective

To test specific standards set in the newly established cleft lip and palate service in three regions of the U.K. The standards relate to record collection and outcomes.

Design

Retrospective analysis.

Patients

Records of 31 children, 5 years of age, who were born in 1997 with complete unilateral clefts of lip and palate and were treated by surgeons in three regions.

Main outcome measures

Record collection standards were measured by collecting dental study models. Outcomes were measured with the 5-Year-Old Index.

Results

Of the 31 subjects, 52% had excellent and good outcomes. The 31 cases represented 62% of the total records collected.

Conclusions

The three regions examined fell short of the standards set, but the outcomes were improved compared with previous national outcomes. The failings in record collection need to be rectified. This study provides baseline data for further development of cleft services within three regions.

Simultaneous 68Ga DOTATATE Positron Emission Tomography/Magnetic Resonance Imaging in Meningioma Target Contouring: Feasibility and Impact Upon Interobserver Variability Versus Positron Emission Tomography/Computed Tomography and Computed Tomography/Magnetic Resonance Imaging

AIMS

The increasing use of highly conformal radiation techniques to treat meningioma confers a greater need for accurate targeting. Several groups have shown that positron emission tomography/computed tomography (PET/CT) information alters meningioma targets contoured by single observers, but whether this translates into improved accuracy has not been defined. As magnetic resonance imaging (MRI) is the cornerstone of meningioma target contouring, simultaneous PET/MRI may be superior to PET/CT. We assessed whether ⁶⁸Ga DOTATATE PET imaging (from PET/CT and PET/MRI) reduced interobserver variability (IOV) in meningioma target volume contouring.

MATERIALS AND METHODS

Ten patients with meningioma underwent simultaneous ⁶⁸Ga DOTATATE PET/MRI followed by PET/CT. They were selected as it was anticipated that target volume definition in their cases would be particularly challenging. Three radiation oncologists contoured target volumes according to an agreed protocol: gross tumour volume (GTV) and clinical target volume (CTV) on CT/MRI alone, CT/MRI+PET(CT) and CT/MRI+PET(MRI). GTV/CTV Kouwenhoven conformity levels (KCL), regions of contour variation and qualitative differences between PET(CT) and PET(MRI) were evaluated.

RESULTS

There was substantial IOV in contouring. GTV mean KCL: CT/MRI 0.34, CT/MRI+PET(CT) 0.38, CT/MRI+PET(MRI) 0.39 (P = 0.06). CTV mean KCL: CT/MRI 0.31, CT/MRI+PET(CT) 0.35, CT/MRI+PET(MRI) 0.35 (P = 0.04 for all groups; P > 0.05 for individual pairs). One observer consistently contoured largest and one smallest. Observers rarely decreased volumes in relation to PET. Most IOV occurred in bone followed by dural tail, postoperative bed and venous sinuses. Tumour edges were qualitatively clearer on PET(MRI) versus PET(CT), but this did not affect contouring.

CONCLUSION

IOV in contouring challenging meningioma cases was large and only slightly improved with the addition of ⁶⁸Ga DOTATATE PET. Simultaneous PET/MRI for meningioma contouring is feasible, but did not improve IOV versus PET/CT. Whether volumes can be safely reduced according to PET requires evaluation.

Training in Clinical Oncology and the Transition from Trainee to Consultant: Results of the Royal College of Radiologists' 2015 Post-Certificate of Completion of Training Survey

AIMS

To seek feedback from clinical oncologists as to their experiences of specialty training and, where applicable, the transition to working as a consultant in the National Health Service.

MATERIALS AND METHODS

All clinical oncologists gaining a Certificate of Completion of Training between 1 July 2012 and 30 June 2014 were identified through records held by the Royal College of Radiologists and approached in May 2015 to take part in an online survey.

RESULTS

The survey was completed by 38 of 80 clinical oncologists invited to take part (48% response rate). Most respondents (>87%) agreed that specialty training equipped them well with clinical skills in radiotherapy planning, systemic therapy and tumour site diagnosis and treatment. This fell to 58% with advanced radiotherapy techniques. Of the non-clinical skills, respondents felt training had equipped them less to deal with leadership and management (53%) and research (48%) than clinical governance (61%). Despite wanting to do so, 42% of respondents did not undertake any out-of-programme (OOP) activity to gain new skills. Most of those respondents who did undertake OOP activity agreed that it helped to prepare them for their first consultant post. There is broad support for the FRCR Examination. The First FRCR Examination modules in physics, pharmacology, tumour biology and radiobiology were seen to be very relevant to clinical practice by 50% or more of respondents. The Final FRCR Examination was seen as essential in a technical specialty like clinical oncology by 92% of respondents. Working as a new consultant, the survey revealed a heavy workload for most respondents, with 69% always or almost always working beyond contracted hours. Other issues of concern identified were discrepancies in advertised consultant job plans and ineffectiveness of the job plan review process. The trainee-consultant transition is often a difficult time, yet only 19% of respondents were allocated a formal mentor. Most respondents had to rely on informal arrangements in seeking support and advice from medical colleagues.

CONCLUSIONS

In general, respondents were satisfied with their specialty training and the transition from training to working as a new consultant. Areas for possible improvement have been identified for employers as well as those involved in organising specialty training.

Erratum to: 36th International Symposium on Intensive Care and Emergency Medicine: Brussels, Belgium. 15-18 March 2016

[This corrects the article DOI: 10.1186/s13054-016-1208-6.].

Continuous hyperfractionated accelerated radiotherapy - Escalated dose (CHART-ED): A phase I study

INTRODUCTION

Patients who present with locally advanced inoperable non-small cell lung cancer (NSCLC) may be suitable for radical radiotherapy. A randomised trial of 563 patients compared CHART and conventional radical radiotherapy (60 Gy/30f) given over 6 weeks and suggested that CHART resulted in a 9% improvement in 2-year survival (Saunders et al., 1999). RT dose escalation for both conventional and CHARTWEL (CHART-WeekEndLess) - fractionation schedules is feasible with modern 3-dimensional CT-based planning techniques and we initiated a phase I CHART dose escalation study in 2009.

METHODS

Patients with WHO performance status 0-2 histologically confirmed, inoperable, stage I-III non-small cell lung cancer were recruited into an open phase I dose escalation trial. Three cohorts of six patients were recruited sequentially. Total dose was escalated from standard CHART radiotherapy of 54 Gy/36f/12 days to 57.6G y (2 × 1.8 Gy fractions on day 15, Group 1), 61.2 Gy (4 × 1.8 Gy fractions on days 15-16, Group 2) and 64.8 Gy (6 × 1.8 Gy fractions on days 15-17, Group 3).

RESULTS

Between April 2010 and May 2012, 18 patients were enrolled from 5 UK centres and received escalated dose radiotherapy. 14 were male, 16 squamous cell histology and 12 were stage IIIA or IIIB. The median age was 70 years and baseline characteristics were similar across the three dose cohorts. One patient did not start escalated radiotherapy but all remaining patients completed their planned radiotherapy schedules. Of these 9 patients have died to date with a median survival of 2 years across the three cohorts. Grade 3 or 4 adverse events (fatigue, dysphagia, nausea and anorexia - classified according to the National Cancer Institute Common Terminology Criteria for Adverse Events (CTCAE) version 4.0) were reported in 6 patients but the pre-specified dose limiting toxicities (grade 4 early oesophagitis; grade 3 cardiac, spinal cord and pneumonitis) were not observed.

CONCLUSIONS

CHART remains a radiotherapy schedule in routine use across the UK and in this dose escalation study no dose limiting toxicities were observed. We feel the dose of 64.8 Gy/42f/17 days should be taken forward into further clinical trials. The sample size used in this study was small so we plan a randomised phase II study that includes other radiotherapy schedules to confirm safety and select an accelerated sequential chemo-radiotherapy schedule to take into phase III studies.

Randomized Phase III Trial of Standard Therapy Plus Low Molecular Weight Heparin in Patients With Lung Cancer: FRAGMATIC Trial

PURPOSE

Venous thromboembolism (VTE) is common in cancer patients. Evidence has suggested that low molecular weight heparin (LMWH) might improve survival in patients with cancer by preventing both VTE and the progression of metastases. No trial in a single cancer type has been powered to demonstrate a clinically significant survival difference. The aim of this trial was to investigate this question in patients with lung cancer.

PATIENTS AND METHODS

We conducted a multicenter, open-label, randomized trial to evaluate the addition of a primary prophylactic dose of LMWH for 24 weeks to standard treatment in patients with newly diagnosed lung cancer of any stage and histology. The primary outcome was 1-year survival. Secondary outcomes included metastasis-free survival, VTE-free survival, toxicity, and quality of life.

RESULTS

For this trial, 2,202 patients were randomly assigned to the two treatment arms over 4 years. The trial did not reach its intended number of events for the primary analysis (2,047 deaths), and data were analyzed after 2,013 deaths after discussion with the independent data monitoring committee. There was no evidence of a difference in overall or metastasis-free survival between the two arms (hazard ratio [HR], 1.01; 95% CI, 0.93 to 1.10; P = .814; and HR, 0.99; 95% CI, 0.91 to 1.08; P = .864, respectively). There was a reduction in the risk of VTE from 9.7% to 5.5% (HR, 0.57; 95% CI, 0.42 to 0.79; P = .001) in the LMWH arm and no difference in major bleeding events but evidence of an increase in the composite of major and clinically relevant nonmajor bleeding in the LMWH arm.

CONCLUSION

LMWH did not improve overall survival in the patients with lung cancer in this trial. A significant reduction in VTE is associated with an increase in clinically relevant nonmajor bleeding. Strategies to target those at greatest risk of VTE are warranted.

USING FLORBETAPIR PET TO INCREASE DIAGNOSTIC CERTAINTY IN ATYPICAL DEMENTIAS

Amyloid PET or CSF can be used to determine Alzheimer pathology in vivo. Few studies have assessed the additional value of amyloid imaging where CSF results are equivocal. We recruited 20 cognitive patients (65.5+/–7.6 y) with MRI, neuropsychology, and CSF Aβ1–42 and tau measured during their diagnostic assessment. Individuals were selected to have a range of CSF results; ten had amnestic and ten non-amnestic presentations. Following the investigations, the treating neurologist gave a diagnosis (AD or non-AD). Four controls (63+/–7.0y) also had CSF examination. All subjects had Florbetapir PET imaging, reported as positive/negative. The clinicians were given the PET results and asked to review their diagnoses. Eighteen patients had positive Florbetapir scans; two patients and all controls were Florbetapir negative. Following initial investigations, thirteen patients were diagnosed with AD, and seven with non-AD pathology. Providing the Florbetapir result led to a change in diagnosis in seven patients, five of whom had atypical phenotypes. For all seven the CSF results were close to or in a “grey” area, where results overlapped for positive and negative PET scans. Even in individuals with CSF measures of Aβ1–42, and tau, Florbetapir PET imaging may have diagnostic utility, particularly in atypical cases and/or equivocal CSF results.

Search for gravitational waves associated with γ-ray bursts detected by the interplanetary network

We present the results of a search for gravitational waves associated with 223 γ-ray bursts (GRBs) detected by the InterPlanetary Network (IPN) in 2005-2010 during LIGO's fifth and sixth science runs and Virgo's first, second, and third science runs. The IPN satellites provide accurate times of the bursts and sky localizations that vary significantly from degree scale to hundreds of square degrees. We search for both a well-modeled binary coalescence signal, the favored progenitor model for short GRBs, and for generic, unmodeled gravitational wave bursts. Both searches use the event time and sky localization to improve the gravitational wave search sensitivity as compared to corresponding all-time, all-sky searches. We find no evidence of a gravitational wave signal associated with any of the IPN GRBs in the sample, nor do we find evidence for a population of weak gravitational wave signals associated with the GRBs. For all IPN-detected GRBs, for which a sufficient duration of quality gravitational wave data are available, we place lower bounds on the distance to the source in accordance with an optimistic assumption of gravitational wave emission energy of 10(-2)M⊙c(2) at 150 Hz, and find a median of 13 Mpc. For the 27 short-hard GRBs we place 90% confidence exclusion distances to two source models: a binary neutron star coalescence, with a median distance of 12 Mpc, or the coalescence of a neutron star and black hole, with a median distance of 22 Mpc. Finally, we combine this search with previously published results to provide a population statement for GRB searches in first-generation LIGO and Virgo gravitational wave detectors and a resulting examination of prospects for the advanced gravitational wave detectors.

Search for gravitational waves associated with γ-ray bursts detected by the interplanetary network

We present the results of a search for gravitational waves associated with 223 γ-ray bursts (GRBs) detected by the InterPlanetary Network (IPN) in 2005-2010 during LIGO's fifth and sixth science runs and Virgo's first, second, and third science runs. The IPN satellites provide accurate times of the bursts and sky localizations that vary significantly from degree scale to hundreds of square degrees. We search for both a well-modeled binary coalescence signal, the favored progenitor model for short GRBs, and for generic, unmodeled gravitational wave bursts. Both searches use the event time and sky localization to improve the gravitational wave search sensitivity as compared to corresponding all-time, all-sky searches. We find no evidence of a gravitational wave signal associated with any of the IPN GRBs in the sample, nor do we find evidence for a population of weak gravitational wave signals associated with the GRBs. For all IPN-detected GRBs, for which a sufficient duration of quality gravitational wave data are available, we place lower bounds on the distance to the source in accordance with an optimistic assumption of gravitational wave emission energy of 10(-2)M⊙c(2) at 150 Hz, and find a median of 13 Mpc. For the 27 short-hard GRBs we place 90% confidence exclusion distances to two source models: a binary neutron star coalescence, with a median distance of 12 Mpc, or the coalescence of a neutron star and black hole, with a median distance of 22 Mpc. Finally, we combine this search with previously published results to provide a population statement for GRB searches in first-generation LIGO and Virgo gravitational wave detectors and a resulting examination of prospects for the advanced gravitational wave detectors.