Evaluation of secondary malignancy risk due to the whole body computerized tomography simulation in radiotherapy facilities

Nowadays, the use of computed tomography (CT) simulation is getting widespread with the use of new treatment modalities like three dimensional conformal radiotherapy (3D-CRT), intensity modulated radiotherapy (IMRT), adaptive radiotherapy (ART) and ste-reotactic radiosurgery (SRS) in radiotherapy facilities. The main purpose of these new treatment modalities are to increase the survival and increase the quality of life by reducing the side effects. However, radiation induced secondary malignancy risk is getting important after radiotherapy with the increase in survival. Especially, CT scanning was performed from head to sacral region for 3D-CRT craniospinal treatments techniques in children or young patients and several precautions should be taken to reduce the radiation dose due to the CT simulation. In this study, we measured organ equivalent dose in Alderson Rando phantom and we estimate radiation-induced cancer risk due to CT scanning for different conditions. According to our measurement, secondary malignancy risk was found to be between 0.10% - 0.22% for different conditions in craniospinal CT simulation.