Calciphylaxis is a rare but devastating condition that has continued to challenge the medical community since its early descriptions in the scientific literature many decades ago. It is predominantly seen in chronic kidney failure patients treated with dialysis (uremic calciphylaxis) but is also described in patients with earlier stages of chronic kidney disease and with normal renal function. In this In Practice feature, we review the available medical literature regarding risk factors, diagnosis, and treatment of both uremic and non-uremic calciphylaxis. High quality evidence for the evaluation and management of calciphylaxis is lacking at this time due to its rare incidence, poorly understood pathogenesis, and the relative paucity of collaborative research efforts. We hereby provide a summary of recommendations developed by the Massachusetts General Hospital's Multi-disciplinary Calciphylaxis Team for calciphylaxis patients.

A cardinal feature of malignant melanoma is its metastatic propensity. An incomplete view of the genetic events driving metastatic progression has been a major barrier to rational development of effective therapeutics and prognostic diagnostics for melanoma patients. In this study, we conducted global genomic characterization of primary and metastatic melanomas to examine the genomic landscape associated with metastatic progression. In addition to uncovering three genomic subclasses of metastastic melanomas, we delineated 39 focal and recurrent regions of amplification and deletions, many of which encompassed resident genes that have not been implicated in cancer or metastasis. To identify progression-associated metastasis gene candidates, we applied a statistical approach, Integrative Genome Comparison (IGC), to define 32 genomic regions of interest that were significantly altered in metastatic relative to primary melanomas, encompassing 30 resident genes with statistically significant expression deregulation. Functional assays on a subset of these candidates, including MET, ASPM, AKAP9, IMP3, PRKCA, RPA3, and SCAP2, validated their pro-invasion activities in human melanoma cells. Validity of the IGC approach was further reinforced by tissue microarray analysis of Survivin showing significant increased protein expression in thick versus thin primary cutaneous melanomas, and a progression correlation with lymph node metastases. Together, these functional validation results and correlative analysis of human tissues support the thesis that integrated genomic and pathological analyses of staged melanomas provide a productive entry point for discovery of melanoma metastases genes.

Background: Cutaneous reactions after COVID-19 vaccination have been commonly reported; however, histopathologic features and clinical correlations have not been well characterized. Methods:We evaluated for a history of skin biopsy all reports of reactions associated with COVID-19 vaccination identified in an international registry. When histopathology reports were available, we categorized them by reaction patterns.Results: Of 803 vaccine reactions reported, 58 (7%) cases had biopsy reports available for review. The most common histopathologic reaction pattern was spongiotic dermatitis, which clinically ranged from robust papules with overlying crust, to pityriasis rosea-like eruptions, to pink papules with fine scale. We propose the acronym ''V-REPP'' (vaccine-related eruption of papules and plaques) for this spectrum. Other clinical patterns included bullous pemphigoid-like (n = 12), dermal hypersensitivity (n = 4), herpes zoster (n = 4), lichen planus-like (n = 4), pernio (n = 3), urticarial (n = 2), neutrophilic dermatosis (n = 2), leukocytoclastic vasculitis (n = 2), morbilliform (n = 2), delayed large local reactions (n = 2), erythromelalgia (n = 1), and other (n = 5).Limitations: Cases in which histopathology was available represented a minority of registry entries. Analysis of registry data cannot measure incidence.

RAF and MEK (mitogen-activated or extracellular signal–regulated protein kinase kinase) inhibitors are effective in treating patients with BRAF-mutant melanoma. However, most responses are partial and short-lived, and many patients fail to respond at all. We found that suppression of TORC1 activity in response to RAF or MEK inhibitors, as measured by decreased phosphorylation of ribosomal protein S6 (P-S6), effectively predicted induction of cell death by the inhibitor in BRAF-mutant melanoma cell lines. In resistant melanomas, TORC1 activity was maintained after treatment with RAF or MEK inhibitors, in some cases despite robust suppression of mitogen-activated protein kinase (MAPK) signaling. In in vivo mouse models, suppression of TORC1 after MAPK inhibition was necessary for induction of apoptosis and tumor response. Finally, in paired biopsies obtained from patients with BRAF-mutant melanoma before treatment and after initiation of RAF inhibitor therapy, P-S6 suppression predicted significantly improved progression-free survival. Such a change in P-S6 could be readily monitored in real time by serial fine-needle aspiration biopsies, making quantitation of P-S6 a valuable biomarker to guide treatment in BRAF-mutant melanoma.

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Purpose:To quantify the affinity of a cationic computed tomography (CT) contrast agent (CA 4+ ) and that of an anionic contrast agent (ioxaglate) to glycosaminoglycans (GAGs) in ex vivo cartilage tissue explants and to characterize the in vivo diffusion kinetics of CA 4+ and ioxaglate in a rabbit model. Materials and Methods:All in vivo procedures were approved by the institutional animal care and use committee. The affinities of ioxaglate and CA 4+ to GAGs in cartilage (six bovine osteochondral plugs) were quantified by means of a modified binding assay using micro-CT after plug equilibration in serial dilutions of each agent. The contrast agents were administered intraarticularly to the knee joints of five New Zealand white rabbits to determine the in vivo diffusion kinetics and cartilage tissue imaging capabilities. Kinetics of diffusion into the femoral groove cartilage and relative contrast agent uptake into bovine plugs were characterized by means of nonlinear mixed-effects models. Diffusion time constants (t) were compared by using a Student t test. Results:The uptake of CA 4+ in cartilage was consistently over 100% of the reservoir concentration, whereas it was only 59% for ioxaglate. In vivo, the contrast material-enhanced cartilage reached a steady CT attenuation for both CA 4+ and ioxaglate, with t values of 13.8 and 6.5 minutes, respectively (P = .04). The cartilage was easily distinguishable from the surrounding tissues for CA 4+ (12 mg of iodine per milliliter); comparatively, the anionic contrast agent provided less favorable imaging results, even when a higher concentration was used (80 mg of iodine per milliliter). Conclusion:The affinity of the cationic contrast agent CA 4+ to GAGs enables high-quality imaging and segmentation of ex vivo bovine and rabbit cartilage, as well as in vivo rabbit cartilage.q RSNA, 2012 Supplemental material: http://radiology.rsna.org/lookup /suppl

Matrix Gla protein (MGP) is a potent inhibitor of vascular calcification. The ability of MGP to inhibit calcification requires the activity of a vitamin K-dependent enzyme, which mediates MGP carboxylation. We investigated how MGP carboxylation influences the risk of calciphylaxis in adult patients receiving dialysis and examined the effects of vitamin K deficiency on MGP carboxylation. Our study included 20 patients receiving hemodialysis with calciphylaxis (cases) and 20 patients receiving hemodialysis without calciphylaxis (controls) matched for age, sex, race, and warfarin use. Cases had higher plasma levels of uncarboxylated MGP (ucMGP) and carboxylated MGP (cMGP) than controls. However, the fraction of total MGP that was carboxylated (relative cMGP concentration = cMGP/[cMGP + uncarboxylated MGP]) was lower in cases than in controls (0.58±0.02 versus 0.69±0.03, respectively; =0.003). In patients not taking warfarin, cases had a similarly lower relative cMGP concentration. Each 0.1 unit reduction in relative cMGP concentration associated with a more than two-fold increase in calciphylaxis risk. Vitamin K deficiency associated with lower relative cMGP concentration in multivariable adjusted analyses (=-8.99; =0.04). In conclusion, vitamin K deficiency-mediated reduction in relative cMGP concentration may have a role in the pathogenesis of calciphylaxis. Whether vitamin K supplementation can prevent and/or treat calciphylaxis requires further study.

After restrictive guidelines regarding GBCA administration were instituted, no new cases of NSF were identified among 52,954 contrast-enhanced MR examinations, including those performed in patients with an eGFR lower than 60 mL/min/m(2).