Comparison of three dimensional conformal radiotherapy and intensity modulated radiotherapy techniques in terms of target volume and critical organ doses in patients with stomach cancer

In this study, three-dimensional conformal radiotherapy (3D-CRT) planning and intensity modulated radiotherapy (IMRT) planning in gastric cancer were performed, and the doses of critical organs and target volumes were compared. Study has been done with Varian model accelerator and Eclipse V13.0 treatment planning system (TPS) at Tokat Gaziosmanpasa University Radiation Oncology Department. 3D-CRT and IMRT plans made at TPS retrospectively, for 30 gastric cancer patients. 3D-CRT plans with four fields were compared with seven field dynamic IMRT plans. For both techniques, PTV, spinal cord, liver, heart, kidney, conformity and homogenity index, number of monitor units (MU) were compared. No significant difference was found between the average dose of PTV, 3D-CRT and IMRT technique (45.8 Gy, 45.5 Gy, respectively). There was no statistically significant difference between MU score for 3D-CRT and IMRT techniques. The value of HI was found to be 0.08 in the 3D-CRT technique and 0.04 in the IMRT technique and a statistically significant difference was observed (p <0.001). No statistically significant difference was found in terms of critical organs. In the treatment of gastric cancer, it was concluded that there was no significant difference in both techniques.