TAHİR ÇAKIR, Gökhan YILMAZER, TAYLAN TUĞRUL

Dosimetric Comparison of 3D-Conformal and IMRT Radiotherapy Techniques in Gastric Cancer

Stomach cancer is a malignancy which has poor prognosis and takes place on the top among deaths related with cancer in the world. Anatomically, stomach has relations with critical organs as heart, liver, kidneys, intestine and spinal cord. Doses which are taken by surrounding critical organs in planning adjuvant radiotherapy of stomach cancer have importance in terms of the control and toxicity. In this study, it was aimed to examine the best dose to target volume and the most appropriate treatment planning technique for maximum protection of organs at risk. The Intensity Modulated Radiation Therapy (IMRT) technique and the 3D-Conformal radiotherapy technique at patients who were operated for stomach cancer were compared in terms of dosimetry. This study was done on the Computed Tomography (CT) simulation images of 21 patients who applied to Van Yüzüncü Yıl University, Radiation Oncology Department. CT simulation of patients was taken with 3 mm thickness at 60th second using intravenous contrast agent. Then CT images were transferred to Prowess Panther treatment planning system. In IMRT planning, 5 fields planning were done with 6 MV photon energy. 3D-conformal planning was performed in 4 fields using 6 and 15 MV photon energy. It is seen that IMRT technique is statistically more advantageous against conformal radiotherapy technique in terms of right-left kidney V20, bilateral kidney V20 and mean dose of liver at the radiotherapy technique applied to the patients who had operation for stomach cancer.

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