IMRT is an advanced form of three-dimensional conformal radiotherapy. It is generally used for individualized irradiation of uneven target areas and for maximum preservation of surrounding normal tissues. With IMRT planning using advanced treatment planning algorithms, dose distributions suitable for the shape of the target can be achieved with a steep dose drop outside the target. In this way, while the maximum dose can be given at the target compared to conformal treatments, it is ensured that the surrounding healthy tissues receive the least dose. Because of these features, it is often used in head and neck tumors and tumors located in the pelvis region.