In ONKOMER, besides external radiation treatments, in-body treatments (Brachytherapy) are also performed. In our center, GAMMAMED PLUS HDR, in which in-body treatments are performed, is a brachytherapy device. Brachytherapy is used in the intra-cavity or intra-tissue radiation therapy of large-volume accessible tumors of tumors in organs with a tubular shape such as the uterus, esophagus, and bronchi. In this treatment system; As a remote control, Iridium -192 radioactive material is placed in the space or tissue in special appliances, and treatment is provided. It is frequently applied in the treatment of uterine and/or cervical tumors. After the patient is hospitalized, the application is made with special applicators and its accuracy is checked. Dose calculations are made in the ECLIPSE Treatment Planning system and then radioactive material is loaded from outside. The treatment takes about 5-15 minutes. The treatment has no side effects to worry about. Treatments are performed as 3D Conformal applications. In three-dimensional applications, planning is made with computed tomography (CT) and magnetic resonance imaging (MRI) methods, and the risky organs to be protected and target volumes to be treated clinically are successfully planned.