1: NMR Biomed. 2008 Mar;21(3):296-300. Molecular electron paramagnetic resonance imaging of melanin in melanomas: a proof-of-concept. Vanea E, Charlier N, Dewever J, Dinguizli M, Feron O, Baurain JF, Gallez B. Biomedical Magnetic Resonance Unit, Université Catholique de Louvain, UCL, Brussels, Belgium. The incidence of malignant melanoma is increasing at an alarming rate. As the clinical outcome of the disease strongly depends on the localization of the lesion, early detection at the initial stages of development is critical. Here, we suggest spatial characterization of melanoma based on the presence of endogenous stable free radicals in melanin pigments. Taking into account the abundance of these naturally occurring free radicals in proliferating melanocytes and their localization pattern, we hypothesized that electron paramagnetic resonance (EPR) imaging could be a unique tool for mapping melanomas with high sensitivity and high resolution. The potential of EPR to image melanoma samples was demonstrated in vitro in animal and human samples. Using EPR systems operating at low frequency, we were also able to record in vivo EPR spectra and images from the melanin present in a subcutaneous melanoma implanted in a mouse. In addition to the proof-of-concept and the achievement of providing the first non-invasive image of an endogenous radical, this technology may represent a key advance in improving the diagnosis of suspected melanoma lesions. Copyright (c) 2007 John Wiley & Sons, Ltd. PMID: 18246539 [PubMed - in process] Related Links Human malignant melanomas with varying degrees of melanin content in nude mice: MR imaging, histopathology, and electron paramagnetic resonance. [J Comput Assist Tomogr. 1990] PMID:2164537 In vivo imaging of free radicals: applications from mouse to man. [Mol Cell Biochem. 2002] PMID:12162454 Electron paramagnetic resonance for small animal imaging applications. [ILAR J. 2001] PMID:11406720 In vivo imaging of a stable paramagnetic probe by pulsed-radiofrequency electron paramagnetic resonance spectroscopy. [Magn Reson Med. 1997] PMID:9339442 High resolution electron paramagnetic resonance imaging of biological samples with a single line paramagnetic label. [Magn Reson Med. 1997] PMID:9094068