Imaging vascular function for early stage clinical trials using dynamic contrast-enhanced magnetic resonance imaging

Many therapeutic approaches to cancer affect the tumour vasculature, either indirectly or as a direct target. Dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) has become an important means of investigating this action, both pre-clinically and in early stage clinical trials. For such trials, it is essential that the measurement process (i.e. image acquisition and analysis) can be performed effectively and with consistency among contributing centres. As the technique continues to develop in order to provide potential improvements in sensitivity and physiological relevance, there is considerable scope for between-centre variation in techniques. A workshop was convened by the Imaging Committee of the Experimental Cancer Medicine Centres (ECMC) to review the current status of DCE-MRI and to provide recommendations on how the technique can best be used for early stage trials. This review and the consequent recommendations are summarised here. Key Points • Tumour vascular function is key to tumour development and treatment • Dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) can assess tumour vascular function • Thus DCE-MRI with pharmacokinetic models can assess novel treatments • Many recent developments are advancing the accuracy of and information from DCE-MRI • Establishing common methodology across multiple centres is challenging and requires accepted guidelines.

Indication of electron neutrino appearance from an accelerator-produced off-axis muon neutrino beam

The T2K experiment observes indications of ν(μ) → ν(e) appearance in data accumulated with 1.43×10(20) protons on target. Six events pass all selection criteria at the far detector. In a three-flavor neutrino oscillation scenario with |Δm(23)(2)| = 2.4×10(-3)  eV(2), sin(2)2θ(23) = 1 and sin(2)2θ(13) = 0, the expected number of such events is 1.5±0.3(syst). Under this hypothesis, the probability to observe six or more candidate events is 7×10(-3), equivalent to 2.5σ significance. At 90% C.L., the data are consistent with 0.03(0.04) < sin(2)2θ(13) < 0.28(0.34) for δ(CP) = 0 and a normal (inverted) hierarchy.

The criminal justice system's considerations of so-called near-virtual autopsies: the East Midlands experience

BACKGROUND

While several research groups champion the potential for postmortem CT (PMCT) to replace the invasive postmortem (PM), many questions still remain.

AIMS

Perhaps the two most important questions are whether PMCT can provide the same level of information as an invasive PM, and arguably more importantly, can it meet the needs of the end users of the PM report. Through a comparative analysis of invasive post-mortem and CT findings and a questionnaire based qualitative thematic analysis, the authors have sought to answer these questions.

RESULTS AND CONCLUSION

Here, the authors show that PMCT is good at providing accurate causes of death and that the interpretation of cases is not significantly altered by the absence of histology. The authors show that in straightforward trauma deaths such as road traffic incidents, there exists the potential for the replacement of the invasive PM by PMCT examination. However, as yet, PMCT cannot provide all of the information that is expected by the criminal justice system in complex forensic cases.

The preparation and biological activity of methyl 5,6-epoxy-retinoate

1. Oxidation of methyl retinoate with monoperphthalic acid gave methyl 5,6-epoxyretinoate, obtained as pale-yellow crystals, m.p. 89 degrees . 2. The structure of the epoxide was confirmed by its ultraviolet, infrared, nuclear-magnetic-resonance and mass spectra. 3. The biological properties of the epoxide were investigated in male and female rats, and were found to be qualitatively similar to those of retinoic acid and methyl retinoate. 4. When administered to male rats reared on a vitamin A-free diet, the epoxide permitted growth although it did not maintain good general health. 5. Rats given a vitamin A-free diet and supplements of the epoxide had degenerate testes. 6. Female rats, maintained on a vitamin A-free diet containing retinoic acid and given supplements of the epoxide during pregnancy, resorbed their foetuses and failed to deliver litters. 7. The threshold of the electroretinogram response in male rats reared on a vitamin A-free diet with supplements of the epoxide was elevated above normal and was similar to that of rats maintained with methyl retinoate. 8. The oral administration of the epoxy acid to rats did not result in the accumulation of the corresponding epoxy alcohol in their livers.

Microwave ablation for unresectable hepatic tumours: clinical results using a novel microwave probe and generator

BACKGROUND

Microwave ablation is an in situ method of tumour destruction used to treat patients with unresectable liver tumours. A new microwave generator and probe, designed to deliver high energy into solid tumours quickly has been developed at our institution. We report the results of its use in patients with unresectable liver tumours treated by a single surgeon in a single institution.

METHODS

Thirty-one patients with 89 unresectable liver tumours were recruited into the study and underwent microwave ablation in a single procedure.

RESULTS

There were no post-operative complications. At a median of 24 months post ablation, 15 patients were alive with 7 patients disease free. At a median of 26 months, 8 patients were alive with tumour recurrence but only 1 with local recurrence. The remaining 7 patients with recurrence were found to have new disease at locations remote from the ablation site. Fourteen patients died of disease progression at a median survival of 15 months, with only 1 patient with local and remote tumour recurrence. Of the total numbers of tumours treated (n=89), a local tumour recurrence rate of 2% was observed. Overall median survival was 29 months with 3 year survival of 40%.

DISCUSSION

Microwave tissue ablation using this novel generator and probe has a low local recurrence and complication rate. Overall survival is comparable to alternative ablation modalities and its ability to treat, even large tumours, with a single insertion of the probe makes it an extremely attractive treatment option.

Neurocognitive contributions to verbal fluency deficits in frontotemporal lobar degeneration

OBJECTIVE

To test the hypothesis that different neurocognitive networks underlie verbal fluency deficits in frontotemporal lobar degeneration (FTLD).

METHODS

Letter ("FAS") and semantic ("animal") fluency tests were administered to patients with a behavioral/dysexecutive disorder (bvFTLD; n = 71), semantic dementia (SemD; n = 21), and progressive nonfluent aphasia (PNFA; n = 26). Tests measuring working memory, naming/lexical retrieval, and semantic knowledge were also obtained. MRI voxel-based morphometry (VBM) studies were obtained on a subset of these patients (bvFTLD, n = 51; PNFA, n = 11; SemD, n = 10).

RESULTS

Patients with SemD were disproportionately impaired on the semantic fluency measure. Reduced output on this test was correlated with impaired performance on naming/lexical retrieval tests. VBM analyses related reduced letter and semantic fluency to anterior and inferior left temporal lobe atrophy. Patients with bvFTLD were equally impaired on both fluency tests. Poor performance on both fluency tests was correlated with low scores on working memory and naming/lexical retrieval measures. In this group, MRI-VBM analyses related letter fluency to bilateral frontal atrophy and semantic fluency to left frontal/temporal atrophy. Patients with PNFA were also equally impaired on fluency tests. Reduced semantic fluency output was correlated with reduced performance on naming/lexical retrieval tests. MRI-VBM analyses related semantic fluency to the right frontal lobe and letter fluency to left temporal atrophy.

CONCLUSIONS

Distinct neurocognitive networks underlie impaired performance on letter and semantic fluency tests in frontotemporal lobar degeneration subgroups.

Computed tomography of projectile injuries

Computed tomography (CT) is a gold standard in clinical imaging but forensic professions have been slow to embrace radiological advances. Forensic applications of CT are now exponentially expanding, replacing other imaging methods. As post-mortem cross-sectional imaging increases, radiologists will fall under increasing pressure to interpret complex forensic cases involving both living and deceased patients. This review presents a wide variety of weapon and projectile types aiding interpretation of projectile injuries both in forensic and clinical practice.

The "biro test" for autonomic dysfunction in carpal tunnel syndrome

The aim of this study was to assess whether autonomic dysfunction associated with carpal tunnel syndrome (CTS) can be assessed quantitatively with a (modified) biro test of finger sweating. Twenty-six hands of 16 patients with CTS were compared with 30 hands of 15 normal subjects. A device was constructed to measure the angle from the horizontal at which a biro slips from the finger (the critical angle). In the control subjects, no significant difference was found in the critical angle between the little and index fingers in either hand. By comparison, in subjects with CTS, the critical angle was significantly lower in the index finger than in the little finger, the mean difference being 8.65 degrees , indicating a quantifiable and significant difference of sweating of the median nerve-innervated index finger.

Superfluid density in a highly underdoped YBa_{2}Cu_{3}O_{6+y} superconductor

The superfluid density rho_{s}(T) identical with1/lambda;{2}(T) has been measured at 2.64 GHz in highly underdoped YBa_{2}Cu_{3}O_{6+y}, at 37 dopings with T_{c} between 3 and 17 K. Within limits set by the transition width DeltaT_{c} approximately 0.4 K, rho_{s}(T) shows no evidence of critical fluctuations as T-->T_{c}, with a mean-field-like transition and no indication of vortex unbinding. Instead, we propose that rho_{s} displays the behavior expected for a quantum phase transition in the (3+1)-dimensional XY universality class, with rho_{s0} proportional, variant(p-p_{c}), T_{c} proportional, variant(p-p_{c});{1/2}, and rho_{s}(T) proportional, variant(T_{c}-T);{1} as T-->T_{c}.

Dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) as a biomarker for the effect of PTK787/ZK 222584 (PTK/ZK) as second-line mono-therapy in patients with stage IIIB or stage IV non-small cell lung cancer (NSCLC)

7676

Background: Overexpression of vascular endothelial growth factor receptor (VEGF-R) in NSCLC-tumors is linked to poor prognosis and shorter overall survival. PTK/ZK (PTK/ZK) is a novel, oral, anti-angiogenic compound blocking all currently known VEGF receptors (VEGF-R1–3). DCE-MRI measures early changes in tumour-associated vasculature in response to treatment and has been successfully used as a biomarker for biological activity of PTK/ZK in liver metastases from colorectal cancer. Methods: This is a prospective, multi- centre, phase-II study of PTK/ZK in pretreated patients with advanced stage NSCLC. 54 patients (pts) received 1,250 mg PTK/ZK once daily (qd), followed by 58 patients receiving 1,250 mg (500 am + 750 mg pm) PTK/ZK twice daily (bid). Response evaluation was based on RECIST. Disease stabilization of at least 12 weeks based on CT/MRI-imaging was defined as clinically relevant drug activity. DCE-MRI was performed 2- 4 hours after PTK/ZK administration, on day 2 and at day 28. Contrast enhancement for the whole tumour was assessed by calculating the transfer constant (Ktrans) using a two-compartment model. Results: DCE-MRI was performed successfully in 35 pts in the qd cohort on day 2 and 29 pts in the qd cohort at day 28. There was a statistically significant mean reduction in Ktrans at day 2 of 35.2 % (p<0.0001, N=35, paired ‘t’ test) and at Day 28 of 38.1% (p<0.0001, N=29). 32 pts with day 2 DCE- MRI were evaluable for response assessment with 10 (31%) achieving SD at 12 weeks and 22 (69%) with progressive disease (PD). Both the SD group and the PD group had significant mean reductions in Ktrans at day 2 (39.4% and 37.1%, respectively). However, the difference between SD and PD was not statistically significant. Data for the bid cohort will be presented at the meeting. Conclusions: PTK/ZK causes statistically significant reduction in tumour vascular parameters of lung tumours. Ktrans has previously been shown to correlate with clinical outcome. However, for the qd cohort, no correlation could be demonstrated. This may be due to the limitation of the sample size as well as the heterogeneity of the targeted lesions selected for this study.

[Table: see text]

Dermatomyositis as a paraneoplastic syndrome in carcinosarcoma of uterine origin

Paraneoplastic syndromes are a collection of disorders affecting an organ or tissue caused by cancer but occurring at a site distant from the primary or metastases. Dermatomyositis can occur in association with malignancy as a paraneoplastic phenomenon. We present a case of a patient presenting simultaneously with an advanced carcinosarcoma of the uterus and dermatomyositis. The diagnoses, pathophysiology and treatment of these two conditions are discussed and current published studies reviewed.

The role of computed tomography in terminal ballistic analysis

Terminal ballistics concerns the science of projectile behaviour within a target and includes wound ballistics that considers what happens when a projectile strikes a living being. A number of soft tissue ballistic simulants have been used to assess the damage to tissue caused by projectiles. Standard assessment of these materials, such as ballistic soap or ordnance gelatine, requires the block to be opened or that a mould to be made to visualize the wound track. This is time consuming and may affect the accuracy of the findings especially if the block dries and alters shape during the process. Therefore, accurate numerical analysis of the permanent or temporary cavity is limited. Computed tomography (CT) potentially offers a quicker non-invasive analysis tool for this task. Four commercially purchased ballistic glycerine soap blocks were used. Each had a single firearm discharged into it from a distance of approximately 15 cm using both gunshot and shotgun projectiles. After discharge, each block was imaged by a modern 16 slice multi-detector CT scanner and analysed using 3-D reconstruction software. Using the anterior-posterior and lateral scout views and the multi-plane reconstructed images, it was possible to visualize the temporary cavity, as well as the fragmentation and dispersal pattern of the projectiles, the distance travelled and angle of dispersal within the block of each projectile or fragment. A virtual cast of the temporary cavity can be also be made. Multi-detector CT with 3-D analysis software is shown to create a reliable permanent record of the projectile path allowing rapid analysis of different firearms and projectiles.