Dosimetric comparison of 3D-conformal and IMRT radiotherapy techniques in gastric cancer

INTRODUCTION: 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 and target volumes which taken by environmental critical organs in planning adjuvant radiotherapy of stomach cancer have importance from in terms of control and toxicity. In this study, it was aimed the examination of the best dose to target volume and the most appropriate treatment planning technique for maximum protection of organs at risk. Intensity Modulated Radiation Therapy(IMRT) technique and the 3D-conformal radiotherapy technique at patients who operated stomach cancer in terms of dosimetric have compared.
METHODS: This study was done on the Computed Tomography(CT) simulation images of 21 patients who applied to Yüzüncü Yýl University, Deparment of Radiation Oncology. CT simulation of patients was taken with 3mm thickness at 60th second using intravenous contrast agent. Then CT images transferred to Prowess Panther treatment planning system. At IMRT planning, 5 fields planning were done with 6MV photon energy. 3D-conformal planning were performed in 4 fields using 6 and 15MV photon energy.
RESULTS: It is seen that IMRT technique is statistically more advantageous against to conformal radiotherapy technique in terms of right-left kidney V20 rate, bilateral kidney V20 rate and mean dose rate of liver at the radiotherapy technique to be applied the patients who operated stomach cancer.
DISCUSSION AND CONCLUSION: IMRT technique is an effective and reliable treatment method for patients who has adjuvant stomach cancer.