Dosimetric Analysis Of Three Dimensional Conformal Radiotherapy And Intensity Modulated Radiotherapy For The Advanced Esophageal Cancer

Objective: To compare the middle thoracic esophageal carcinoma of the dosimetric difference with three-dimensional conformal radiotherapy(3D-CRT)and different radiation field of intensity-modulated radiotherapy(IMRT).Methods: The 15 patients of thoracic esophageal cancer were diagnosed for the first time in our hospital from2015.2-2015.12,patients were positioned under simulated CT,and data is transferred to the Elekta planning system.The planned target areas of all patients were delineated with a unified standard,3D-CRT,IMRT-5 beams,IMRT-7 beams,IMRT-9 beams of the 4radiotherapy plans were made respectively,dosimetric parameters of 4 radiotherapy were analyzed using one-way ANOVA analysis,P < 0.05 is statistically significant difference.Results: 3DCRT and IMRT were able to satisfy 95% is dose curve ? 95%PTV volume dosimetric requirements,3D-CRT and IMRT of the conformal index(CI),high dose(V105)volume,average dose(Dmean)were significantly different(P < 0.05).There was significant difference in V20 between IMRT and 3DCRT(P < 0.05),the low dose area of the double lung increased with the increase of IMRT's beam,and the high dose area decreased with the increase of the IMRT's beam.There was significant difference in the maximum dose of spinal cord(Dmax)between 3DCRT and IMRT(P < 0.05),and the Dmax decreased with the increase of the IMRT's beam.There was no significant difference in heart(P > 0.05).There were significant differences in MU and effective treatment time between 3DCRT and IMRT(P < 0.05).Conclusion: 3D-CRT and IMRT are perfect for esophageal cancer in the middle thoracic esophagus,IMRT's CI and the protection of the organs are slightly superior overall,but 3D-CRT can reduce the accelerator's MU,a single treatment time is shorter,patients can benefit from treatment.