Head and neck tumor segmentation in PET/CT: The HECKTOR challenge

This paper relates the post-analysis of the first edition of the HEad and neCK TumOR (HECKTOR) challenge. This challenge was held as a satellite event of the 23rd International Conference on Medical Image Computing and Computer-Assisted Intervention (MICCAI) 2020, and was the first of its kind focusing on lesion segmentation in combined FDG-PET and CT image modalities. The challenge’s task is the automatic segmentation of the Gross Tumor Volume (GTV) of Head and Neck (H&N) oropharyngeal primary tumors in FDG-PET/CT images. To this end, the participants were given a training set of 201 cases from four different centers and their methods were tested on a held-out set of 53 cases from a fifth center. The methods were ranked according to the Dice Score Coefficient (DSC) averaged across all test cases. An additional inter-observer agreement study was organized to assess the difficulty of the task from a human perspective. 64 teams registered to the challenge, among which 10 provided a paper detailing their approach. The best method obtained an average DSC of 0.7591, showing a large improvement over our proposed baseline method and the inter-observer agreement, associated with DSCs of 0.6610 and 0.61, respectively. The automatic methods proved to successfully leverage the wealth of metabolic and structural properties of combined PET and CT modalities, significantly outperforming human inter-observer agreement level, semi-automatic thresholding based on PET images as well as other single modality-based methods. This promising performance is one step forward towards large-scale radiomics studies in H&N cancer, obviating the need for error-prone and time-consuming manual delineation of GTVs.     

A study from The Mayo Clinic evaluated long-term outcomes of kidney transplantation in patients with immunoglobulin light chain amyloidosis

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A proposal: How to study pro-myelinating proteins in MS

Multiple sclerosis (MS) is an inflammatory and degenerative disease of the CNS. An unmet need in MS is repair i.e.,promoting endogenous regeneration and remyelination after demyelinating inflammatory injury. Remyelination is critical in neuronal preservation and the prevention of clinical progression. There is a good deal of evidence for histological repair and remyelination in MS patients. Repair is driven by several prominent endogenous pro-myelinating proteinsincluding neural cellular adhesion molecule (N-CAM) and brain derived neurotrophic factor (BDNF) among others. To follow changes during acute re-myelination in vivo in MS subjects, non conventional MRI techniques are necessary such as quantitative susceptibility mapping (QSM) that detects the release of Fe from dying oligodendroglial cells and myelin water imaging (MWI) that detects water captured within newly formed myelin.The best time to monitor changes in pro-myelinating proteins and link those changes to imaging evolution is immediately after the acute inflammatory response in MS lesions (gadolinium enhancement [Gd+]) during an intense period of remyelination. We can monitor MS subjects with new Gd + lesions with periodic imaging along with sampling of blood and CSF and determine if myelin formation is linked with increases in pro-myelinating proteins. This would lead to potential therapeutic manipulation with directly administered proteins to promote CNS re-myelination in animal models and in early clinical trials.