Comparison of three dimensional conformal radiotherapy and intensity modulated radiotherapy techniques in pancreas cancer

Pancreatic cancer is the highly invasive and metastasis potential. Pancreatic cancer is rarely observed but represents 5% of the cancer deaths. Both curative and palliative radiotherapy is applied as pancreatic cancer. Treatment plans for 10 patients with pancreatic cancer diagnosis were done with intensity-modulated radiotherapy (IMRT) and the widely used three dimensional conformal radiotherapy (3DCRT). The purpose of this study is to examine these plans? effectiveness and compare the target coverage and critical organs dose with the help of dose volume histograms (DVH). In the first stage of study, each patient?s 2, 3 and 4 different fields in 3DCRT technique with 18 MV photon energy were used. In the fields, plans were prepared for Planning Target Volume to 45 Gy, for Gross Tumor Volume to 50,4 Gy. 7 fields in IMRT technique were planned for PTV to 45 Gy and for GTV to 50 Gy. 3DCRT was compared with IMRT plans, maximum dose of PTV and GTV respectively, 3.3 Gy and 1.9 Gy decreased. According to ICRU 83, IMRT plans for PTV 856%, 2027% for the GTV provides a more homogeneous dose distribution. In addition, conformity index increased by 42% to ICRU 62 and 45% to ICRU 83. When compared with the 3DCRT, in IMRT plans, the maximum dose of the liver was increased 4.5 Gy, the maximum dose of the spinal cord decreased 5.1 Gy. A dose of 20 Gy in the right kidney, left kidney and bilateral kidney volume decreased 3.3%, 2.9% and 1.2%. As a result of the study, according to 3BKRT, IMRT technique that is more homogeneous dose distribution for target volumes is provided, spinal cord and kidneys were better preserved.