“Pretend”Bolus在乳腺癌根治术后调强放疗应用中的剂量学研究

摘要

目的:研究填充物在乳腺癌根治术后调强放疗计划中的剂量并进行比较,并探讨乳腺癌根治术后调强放疗的理想方案.方法:选取15例乳腺癌根治术后病人进行计划设计,应用Pinnacle9.2计划系统,采用5～6个照射野制定两组计划,分别为加填充物(Bolus)和不加填充物计划,使用相同的剂量-体积约束条件,处方剂量均为200 cGy/25day,比较这两个计划PTV的适形度和剂量均匀性,双全肺及患侧肺的V5,V20,V30等剂量学指标.结果:使用BOLUS的IMRT计划能获得较满意的剂量分布,两种方法相比,除了靶区剂量,其余危及器官的剂量受量差异均无统计学意义.肺受量改变不明确,P＞0.05.结论:加了BOLUS做调强计划,大大提高了计划的适形度和均匀性,对某些患者可以减少肺V20,V30等剂量.结论:建议临床对于对乳腺癌根治术后的患者,做IMRT计划时加入0.5 cm的填充物,可以提高表面剂量和靶区适形度.%Objetcive: To study the dose of intensity modulated radiotherapy with bolus of post-operative patienta with breast cancer and study the appropriate treatment pianning.Methods: For 15 post-operative patients with breast cancer.with the same dose volume constrac,with 5-6 fields were design,5000 cGy dose was gave to PTV,and 200 cGy/Day,max dose ,min dose, mean dose in PTV,and dose volume of risk organs(OAR) were used for comparison of these plans.Results: The IMRT plan with bolus could produce a good dose distribution.conformity index (Cl)and HI of target were improved as the addition of bolus.except for Hl.the irradiated dose of other OARs had no diffrentce between these two plans.Conclusions: in order to improve the dose of superficialand surface buildup dose,0.5 cm bolus is needed.