早期乳腺癌保乳术后三维适形放疗与常规放疗靶区及同侧肺的剂量比较  

Comparison of conventional radiotherapy and 3-D conformal radiotherapy on targets and ipsilateral lung in early breast cancer after conservative surgery

作　　者：丁喆[1] 夏新舍[1] 闫钢[1] 王艳阳[1] 王勇[1] 刘爱娟[1] 

机构地区：[1]宁夏医科大学总医院肿瘤医院放疗科,宁夏银川750004

出　　处：《宁夏医学杂志》2012年第12期1244-1246,共3页Ningxia Medical Journal

摘　　要：目的比较早期乳腺癌保乳术后常规放疗与三维适形放疗的靶区及同侧肺的受照剂量。方法 50例早期乳腺癌保乳术后患者接受三维适形放疗,所有病例在同一CT定位片上进行常规二野切线照射计划的设计,处方剂量为靶区50 Gy,瘤床区加量10 Gy,总量60 Gy。通过剂量体积直方图(DVH)分别对两种计划中靶区-计划肿瘤体积(PTV)、剂量均匀性系数(HI),同侧肺的剂量进行比较。结果三维适形放疗计划与常规二野切线计划的剂量体积百分比V95%分别为(99±0.00)%、(99±1.00)%(P=0.395);三维适形放疗计划的V 105%、V 110%、V 115%与常规二野切线计划比较分别降低(22.4±0.13)%、(48.1±0.15)%和(13.9±0.12)%(P<0.005);剂量均匀性系数(HI)减少0.09±0.07(P<0.005);同侧肺的V20、V30分别升高(5±0.05)%和(4±0.04)%,但总体均值(18.5±0.15)%和(15.3±0.04)%,均<评价标准20%(P<0.001)。结论早期乳腺癌保乳术后三维适形放疗和常规二野切线放疗均能很好覆盖肿瘤体积保证处方剂量的实施,但三维适形计划较常规二野切线计划明显降低正常组织的高剂量体积,剂量均匀性明显提高,尽管少量增加了同侧肺的受照,但均在限定范围之内。Objective To compare the doses of conventional radiotherapy and 3 - D conformal radiotherapy on targets and ipsilateral lung for early stage breast cancer after conservative surgery. Methods 50 patients received 3 - D conformal radiotherapy （3 D - CRT） All patients were given conventional radiotherapy （CRT） plan using same CT information. Prescription dose was 50 Gy in breast volume with X - ray, and added boost dose was 10 Gy in tumor bed, with a total dose was 60 Gy. Planning target volume （ PTV）, homogeneity index （HI） and ipsilateral lung dose were evaluated with dose volume histogram （DVH） in two plans. Results Volume of 95% of dose prescription （V95%） was（99 ±0.00）%, （99± 1.00）% （P =0. 395） with 3D - CRT and CRT, respectively, while V105%, V110% andV115% were reduced with （22.4±0.13）%,（ 48.1 ±0.15）% and （13.9＋0.12）%, （P〈0.001） in two plans, respectively. HI was 1.08 ± 0.02 and 1.18 ±0.09 （P 〈 0. 001 ） with 3D - CRT and CRT. Volume of 20 Gy and 30 Gy received by ipsilateral lung （V20 and V30） increased（5 ± 0.05）% and （4 ±0. 04）%, but each of the volume was less than 20%, which was acceptable within evaluation standard. Conclusion For early stage breast cancer after conservative surgery, 3D - CRT has same efficacy of taking tumor volume irradiation and has lower volume of high dose compared with CRT. HI of 3D - CRT is increased. Ipsilateral lung is still within evaluation standard, although the volume is rised a little in 3D -CRT.

关 键 词：乳腺肿瘤 保乳手术 放射疗法 

分 类 号：R737.9[医药卫生—肿瘤]