What is the image-guided radiotherapy (IGR)?
The combination of medical imaging and radiotherapy constitutes an important research field, for the group “NCM” of UTINAM Institute (Université de Franche Comté, Besançon, France). Our studies aims at rendering radiotherapy more specific by concentrating the dose deposition of the radiation in the tumour while sparing the healthy tissues. For achieving this goal, multifunctional gold nanoparticles are in the heart of our research activities since these nanoparticles exhibit a great potential for radiosensitization and medical imaging. Their presence in the tumor will increase the deleterious effect of the radiation in order to specifically eradicate the cancerous cells. The cells appear therefore more sensitive to the therapeutic radiation. Indeed the preferential absorption of the ionizing radiation (X- or γ-rays) by the gold nanoparticles will produce a shower of highly reactive radicals which will seriously alter the tumor. Owing to the combination of medical imaging and therapy, the most opportune moment (high content of nanoparticles in tumour and low content in healthy tissues) can be determined for activating the therapeutic effect of gold nanoparticles. In other words, the radiotherapy is guided by imaging. The treatment by radiotherapy was based on MRT (Microbeam Radiation Therapy). MRT is a non-conventional irradiation technique performed at the ESRF (European Synchrotron Radiation Facility, Grenoble, France). The therapeutic radiation is constituted by an array of parallel microbeams.