Dosimetry Study Of Three-dimension Conformal Radiation Therapy(3DCRT) In Treatment Cervical Cancer Recurred In Pelvis

Objective Through dose-volume histogram(DVH),to compare the dose distribution of three-dimension conformal radiation therapy(3DCRT) and common radiation therapy(CRT) of the planning target volume(PTV) and organ at risk(OAR) in recurred cervical cancer treatment planning.Methods Thirteen patients,who had cervical cancer recurred in pelvis treated with 3DCRT were selected.After CT simulation,the CT images were transferred into treatment planning system.The same physicist designed 3DCRT plan and common radiation therapy plan(CRT) (anteroposterior-posteroanterior opposed fields,AP/PA)for every patient,total dose 50Gy,90% isdose covered the PTV,then compared the dose distribution of PTV and OAR.Results At the same prescribed dose of 50Gy,there were no significant differences,on OAR maximum dose between 3DCRT plans and CRT(AP/PA) plans(P＞0.05),however,there was significant differences on PTV maximum dose(P＜0.001).The difference of PTV uniformity were significant between 3DCRT plans and CRT(AP/PA) plans(P＜0.001).Compared the high dose region of OAR(V40),the difference was significant(P＜0.001). Between 3DCRT plans and common radiation therapy plans,showed 83.58%,90.67%,49.50% median reduction in the V40 of rectum,bladder,intestine,respectively.Conclusions At the same PTV coverage of the prescribed dose,3DCRT plans showed worse dose uniformity.however,the radiation volume to organs at risk in 3DCRT plans were smaller than common radiation therapy plans.So,patients with cervical cancer recurred in pelvis received 3DCRT may be potentially diminish the Normal Tissue Complications Probability。...