Masha has a malignant brain tumor - diffuse astrocytoma. Surgical removal of the tumor in this case is impossible because of its location. Proton irradiation is required to eliminate a tumor. The main advantage of this type of treatment is the ability to deliver maximum doses of radiation to the center of the tumor, while simultaneously reducing the intensity of radiation at its boundary. This minimizes the impact on healthy brain cells. This method of treatment is the most effective and gentle for the child.