Comparison of KVCBCT based on deformable image registration of adaptive planning and static 3DCRT planning for patients with lung cancer / 中华放射肿瘤学杂志

ABSTRACT

ObjectiveTo comparison of kilo-voltage cone-beam CT (KVCBCT) deformable image registration of adaptive planning and static planning for patients with lung cancer,and evaluate their characters.MethodsFive patients with lung cancer were in the study.Two sets image were acquired every three days and were concatenated to one set.Ten sets CBCT image and planning CT image were transferred a commercial deformable image registration software.The planning CT was deformed to each set CBCT and the contours delineated,the new contour were labeled CBCTf1 -CBCTf10.Transfer of each deformed planning CT and CBCTf1 -CBCTf10 back into the treatment planning system enable re-calculation of actual dose distribution,then we obtain CT planning and fractional CBCT contour planning,the CBCT planning were labeled CBCTp1-CBCTp10.Ten times CBCT planning of every patient were added to acquire a total dose accumulation planning ( DA plan ),comparison of dose distribution and dose-volume histogram in CT plan and DA plan for fractionation dose and accumulation dose of left,right,total lung,PTV and spinal-cord.The difference of two plan was analyzed by Wilcoxson's sign rank test.ResultsThe max and min dose of PTV,the left,right,total lung V5,V10,V20,V30,V50,spinal-cord max dose,and the left,right and total lung mean dose in DA plan were smaller than in CT plan (z=-2.02 - -2.03,P＜0.05).The mean dose of PTV and D95 in DA plan was as well as in CT plan (z=-1.48,-1.21,P=0.138,0.225).ConclusionsKVCBCT based deformable image registration of adaptive planning reduce the dose of lung and spinal-cord,and enhance the dose of PTV.This provides a tool for exploring adaptive radiotherapy strategies.