The Proton Therapy Center is located in Orsay. It is one of the three technical platforms in the Radiotherapy department at Institut Curie. The first treatments administered were for melanoma of the eye, but since then tumor locations treated have become more diverse, with treatment of certain tumors at the base of the skull in particular, in adults and children. The therapeutic indications continue to widen to be able to offer this ultra-precise radiotherapy to a larger number of children. Proton therapy helps to limit side effects (reduction in the volume of healthy tissues irradiated, and thus fewer orthopedic after effects and reduced risk of radio-induced cancer), which is in fact the notable benefit in pediatrics.