摘要
目的评价乳腺癌改良根治术后CT模拟定位下胸壁电子线照射的靶区和心肺受照体积和剂量分布情况。方法20例有胸壁照射适应证的乳腺癌改良根治术后患者,行CT模拟定位,三维治疗计划系统将CT图像进行数字化重建,勾画胸壁CTV及心、肺等危及器官,并计算胸壁及其心、肺受照体积和受照剂量。胸壁处方剂量为5000cGy。结果左侧乳腺癌靶区的Dmax为(5536±301)cGy、Dmean为(4823±129)cGy、D90为(4543±290)cGy,同侧肺Dmean为(1724±624)cGy、V20为(36±13)%。心脏Dmean为(1008±457)cGy、V30为(13±9)%。右侧乳腺癌靶区的Dmax为(5554±253)cGy、Dmean为(4783±89)cGy、D90为(4496±101)cGy、同侧肺Dmean为(1416±567)cGy、V20为(30±12)%。结论通过CT模拟定位制定胸壁电子线照射放疗计划,能更准确地了解靶区和正常组织的剂量分布,从而能更好地优化放疗计划。
Objective To evaluate the dosimetry of electron beam with the use of computed tomography （CT）- based radiotherapy on chest wall for postmastectomy patients. Methods CT simulation was conducted for 20 breast cancer patients having received electron beam chest wall irradiation after postmastectomy, and digitizing reconstitution of the image pictures from spiral CT equipment and outlining the clinical target volume （CTV）and organs at risks （OARs）such as heart and lung, calculating their volume and exposure dose ,were done by the 3D treatment planning system （TPS）. The prescribed dose for chest wall was 5 000 cGy. Results The maximum dose （Dmax） ,mean dose （D mean） and dose of 90% CTV （D90） for the left breast cancer were （5 542 ± 279）cGy, （4 809 ± 116）cGy and （4 526 ± 239）cGy respectively. The Dmean and percentage of volume receiving more than 20 Gy （V20） and 10 Gy （V10 ） of left lung were （ 1 616±608 ） cGy, （ 33 ± 13） % and （ 44 ± 16 ）% respectively. The mean dose （Dmean） and volume receiving more than 30 Gy （V30） of heart were （1 008 ± 457） cGy and （13±9）%. The Dmax,Dmean and D90 for the right breast cancer were （5 554± 253）cGy,（4 783 ± 89）cGy and （4 496± 101 ）cGy respectively, the I）nean,V20 of right lung were （1 416± 567）cGy, （30 ±12） respectively. Conclusion By the use of computed tomography （CT）-based to perform the plan of electron-beam radiotherapy on chest wall, we can understand precisely the dosimetry of the target volume and normal structures, and perfect the radiation plan better.
出处
《肿瘤防治研究》
CAS
CSCD
北大核心
2008年第9期671-673,共3页
Cancer Research on Prevention and Treatment
关键词
乳腺癌
根治术后放疗
电子线
胸壁
Breast cancer
Postmastectomy radiotherapy
Electron beam
Chest wall
