Development and optimization of magnetic resonance-based methods for the detection and staging of malignant melanoma : EPR imaging and high-field MRI

(eng) Amongst all the forms of cancer, melanoma is not the most frequent, nor is it the most deadly. However, its incidence rises year after year, faster than most of the other cancers. While the cumulative lifetime risk to develop a melanoma was 1/140 in 1975, it is now estimated at 1/50 in United-States and Western Europe, meaning that 2% of the population will develop a melanoma during their life. Of course, the evolution of the diagnosis strategies explains partially this increase, but our inappropriate behaviour face to the sun remains the main causative factor. In this work, we provided an overview of the melanoma problematics, from the melanocyte function to the tumor treatment. A special interest was shown for the methods of diagnosis, the routinely used as well as the innovative techniques. Two magnetic resonance imaging-based methods, electron paramagnetic resonance imaging (EPRI) and magnetic resonance imaging (MRI), were particularely investigated. After a brief description of their principles of functioning, we tried to determine how these unconventional methods could be helpful in field of melanoma research and, by means of experimental studies, we displayed their advantages and inconvenients. In the final part of the work, we discussed the implications of our results on potential clinical uses and more concretely, the importance of the pigmentation for the success of EPR measurements. Our works did not pretend to give rise to a perfect method of diagnosis. Nevertheless, we hope that our results could provide concrete elements useful for the further development of EPR and MRI as tools for the study of melanoma.