BackgroundAmong the modalities for lung imaging, proton magnetic resonance imaging (MRI) has been the latest to be introduced into clinical practice. Its value to replace X-ray and computed tomography (CT) when radiation exposure or iodinated contrast material is contra-indicated is well acknowledged: i.e. for paediatric patients and pregnant women or for scientific use. One of the reasons why MRI of the lung is still rarely used, except in a few centres, is the lack of consistent protocols customised to clinical needs.MethodsThis article makes non-vendor-specific protocol suggestions for general use with state-of-the-art MRI scanners, based on the available literature and a consensus discussion within a panel of experts experienced in lung MRI.ResultsVarious sequences have been successfully tested within scientific or clinical environments. MRI of the lung with appropriate combinations of these sequences comprises morphological and functional imaging aspects in a single examination. It serves in difficult clinical problems encountered in daily routine, such as assessment of the mediastinum and chest wall, and even might challenge molecular imaging techniques in the near future.ConclusionThis article helps new users to implement appropriate protocols on their own MRI platforms.Main Messages• MRI of the lung can be readily performed on state-of-the-art 1.5-T MRI scanners.• Protocol suggestions based on the available literature facilitate its use for routine• MRI offers solutions for complicated thoracic masses with atelectasis and chest wall invasion.• MRI is an option for paediatrics and science when CT is contra-indicated

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Therapy monitoring in oncological patient care requires accurate and reliable imaging and post-processing methods. RECIST criteria are the current standard, with inherent disadvantages. The aim of this study was to investigate the feasibility of semi-automated volumetric analysis of lymph node metastases in patients with malignant melanoma compared to manual volumetric analysis and RECIST. Multislice CT was performed in 47 patients, covering the chest, abdomen and pelvis. In total, 227 suspicious, enlarged lymph nodes were evaluated retrospectively by two radiologists regarding diameters (RECIST), manually measured volume by placement of ROIs and semi-automated volumetric analysis. Volume (ml), quality of segmentation (++/--) and time effort (s) were evaluated in the study. The semi-automated volumetric analysis software tool was rated acceptable to excellent in 81% of all cases (reader 1) and 79% (reader 2). Median time for the entire segmentation process and necessary corrections was shorter with the semi-automated software than by manual segmentation. Bland-Altman plots showed a significantly lower interobserver variability for semi-automated volumetric than for RECIST measurements. The study demonstrated feasibility of volumetric analysis of lymph node metastases. The software allows a fast and robust segmentation in up to 80% of all cases. Ease of use and time needed are acceptable for application in the clinical routine. Variability and interuser bias were reduced to about one third of the values found for RECIST measurements.

A method of four-dimensional (4D) magnetic resonance imaging (MRI) has been implemented and evaluated. It consists of retrospective sorting and slice stacking of two-dimensional (2D) images using an external signal for motion monitoring of the object to be imaged. The presented method aims to determine the tumour trajectories based on a signal that is appropriate for monitoring the movement of the target volume during radiotherapy such that the radiation delivery can be adapted to the movement. For evaluation of the 4D-MRI method, it has been applied to a dynamic lung phantom, which exhibits periodic respiratory movement of a porcine heart-lung explant with artificial pulmonary nodules. Anatomic changes of the lung phantom caused by respiratory motion have been quantified, revealing hysteresis. The results demonstrate the feasibility of the presented method of 4D-MRI. In particular, it enables the determination of trajectories of periodically moving objects with an uncertainty in the order of 1 mm.

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Radiotherapy for organs with respiratory motion has motivated the development of dynamic volume lung imaging with computed tomography (4D-CT) or magnetic resonance imaging (4D-MRI). 4D-CT can be realized in helical (continuous couch translation during image acquisition) or cine mode (translation step-by-step), either acquired prospectively or reconstructed retrospectively with temporal resolutions of up to 250 msec. Long exposure times result in high radiation dose and restrict 4D-CT to specific indications (ie, radiotherapy planning). Dynamic MRI accelerated by parallel imaging and echo sharing reaches temporal resolutions of up to 10 images/sec (2Dþt) or 1 volume/s (3Dþt) that allow analyzing respiratory motion of the lung and its tumors. Near isotropic 4D-MRI can be used to assess tumor displacement, chest wall invasion, and segmental respiratory mechanics. Limited temporal resolution of dynamic volume acquisitions (in their current implementation) may lead to an overestimation of tumor size, as the mass is volume averaged into many voxels during motion. Nevertheless, 4D-MRI allows for repeated and prolonged measurements without radiation exposure and therefore appears to be appropriate for patient selection in motion-adapted radiotherapy as well as for a broad spectrum of scientific applications.

Objective: Medullary thyroid carcinoma (MTC) is often associated with gain-of-function mutations in the RET proto-oncogene, which is found in all hereditary cases and most sporadic cases. The activated RET receptor tyrosine kinase can be inhibited by tyrosine kinase inhibitors in vitro. We evaluated the efficacy of treatment with imatinib mesylate, a tyrosine kinase inhibitor, in patients with advanced MTC. Design and patients:In this open-label clinical trial, nine patients, eight with sporadic and one with hereditary MTC, with unresectable, measurable, progressive metastases were treated with imatinib mesylate 600 mg daily. The tumour response to imatinib was evaluated after 3, 6 and 12 months by computed tomography and after 1 month by 18 F-fluoro-2-deoxy D-glucose position-emission tomographic scanning. The median duration of therapy was 8 months.Results: Overall, stable disease occurred in five patients for up to 6 months and in one patient for up to 12 months, with a median duration of progression-free survival of 6 months. Four patients had progressive disease after 12 months. One patient stopped therapy after 2 weeks because of worsening of diarrhoea. Therapy was well tolerated, although transient mild-to-moderate nausea (nZ3), oedema (nZ3), diarrhoea (nZ2) and skin rash (nZ2) were observed. Conclusion: Imatinib mesylate is well tolerated, no tumour remission was observed, only transient stable disease was achieved in some patients with advanced MTC.European Journal of Endocrinology 157 215-220

HMGB1 serum levels are significantly higher in GPA with predominant granulomatous manifestations and correlate with volumes of pulmonary 'granuloma'. HMGB1 may be used as a marker of the burden of granulomatous inflammation in GPA.