Objective: Different statistical methods are used to evaluate the performance of risk prediction models. Many technologies and planning systems have been developed in radiotherapy (RT) applications from past to present. We aimed to compare these systems and compare the methods available in our clinic when choosing the most suitable-cheap device-planning system for the patient.

Materials and Methods: Treatment simulation computed tomography of 10 patients with T12-L5 vertebral bone metastases treated in our clinic were used. Target and normal tissue volumes of each patient were contoured by the same radiation oncologist. As Clinical Target Volume (CTV) , T12-L5 vertebral bones and 0.5 cm margins in all directions were given and Planing Target Volume (PTV) was created. Three separate plans were made for each patient by the same expert radiation oncology physicist with 3D-CRT( three-dimensional (3D) radiotherapy), IMRT(intensity modulated radiation therapy) and VMAT (volumetric modulated arc therapy) techniques. In total, 30 plans were studied. A total dose schedule of 40 Gy with a daily fraction of 200 cGy was used as the treatment dose. Homogenity index (HI) and conformality index (CI) were calculated. Medulla spinalis (MS) and renal doses from normal tissues were compared. In addition, total Monitor Unit (MU) and PTV doses were also examined.

Results: PTV40 mean doses were lower in IMRT, and D5% doses were highest in 3D-CRT plan (p<0.001). While there was no significant difference between HI and MS max plans (p>0.001), CI, right kidney mean and left kidney mean doses showed significant differences (p<0.001). The lowest MU value was obtained in the 3D-CRT plan (p<0.001).

Conclusion: In RT applications, especially for the palliation of bone metastases such as the lumbar vertebra, each clinic can easily use 3D-CRT, IMRT and VMAT systems, if available. In addition, since the session duration is shorter. 3D-CRT can be used in patients if there is no additional renal disease.