左侧乳腺癌保乳术后各种放疗技术剂量学评价  

Dosimetric evaluation on irradiation techniques for left breast cancer

作　　者：刘桂红[1] 徐钰梅[1] 唐天友[1] 王建设[1] 陈勇[1] 曹忠诚[1] 刘伟[1] 章龙珍[1] 

机构地区：[1]徐州医学院附属医院放疗科,江苏徐州221002

出　　处：《徐州医学院学报》2011年第10期666-669,共4页Acta Academiae Medicinae Xuzhou

基　　金：基金项目：江苏省卫生厅科技项目（H201021）;徐州市科技项目（XF10C078）

摘　　要：目的比较左侧乳腺癌保乳术后常规放疗（CR）、三维适形放疗（3D—CRT）、四野及五野调强放疗（IMRT）靶区剂量分布差异。方法随机选择14例左侧乳腺癌保乳术后患者，为每例患者设计上述4种照射技术的治疗计划。处方剂量为50Gy／25次。所有计划都使90％-95％靶区体积达到处方剂量要求。分别比较靶区剂量适形性、均匀性以及心肺所受剂量。结果3D—CRT和IMRT靶区剂量均匀度和适形度明显优于CR；IM—RT技术在正常组织的保护方面优于3D—CRT，3D—CRT技术优于CR。IMRT技术使患侧肺、心脏高剂量区体积降低，低剂量区增加，使对侧肺平均受照剂量增加。与四野[MRT相比，五野IMRT虽然改善了靶区的均匀性及适形度，但增加了患侧肺V5、V10及右肺平均剂量，而心脏及患侧肺高剂量区却无明显改善。结论与CR相比，3D—CRT和IMRT能够明显改善靶区均匀性和适形度，降低了患侧肺、心脏高剂量受照体积；在降低心脏及患侧肺高剂量体积方面，IMRT明显优于3D—CRT；四野IMRT是取代CR的最佳选择。Objective To evaluate the benefit of conventional radiotherapy （CR）, three dimensional conformal radiotherapy （3D- CRT） and intensity -modulated radiotherapy （IMRT） in target dose uniformity and normal tissue sparing for left breast cancer. Methods For each of 14 randomly chosen patients, 4 plans were designed for 4 irradiation techniques. The prescribed dose was 50 Gy/25f, 90% - 95% of the planning target volume received this dose. Target dose homogeneity and conformity, and dose received by heart and lung were compared. Results For 2 IMRT techniques and 3D- CRT technique, the dose homogeneity and conformity in target were improved compared with CR. The dose homogeneity and conformity in target were best for five - field IMRT. Normal tissue protection for 3D - CRT was better than CR, and better than 3D - CRT for IMRT. For IMRT, high dose volume for ipsilateral lung and heart was decreased while low dose volume and average dose of con - lung were increased. Low dose volume of ipsilateral lung and heart was greatly increased for five - field IMRT, but high dose volume of heart and ipsilateral lung was not decreased significantly compared with four -field IMRT. Conclusions Compared with CR, 3D - CRT and IMRT can improve the homogeneity and conformity of planning target volume （ PTV ） , reduce the irradiated volumes of ipsiiateral lung and heart receiving fairly high dose, while IMRT is better than 3D - CRT. For current radiotherapy practice, four - field IMRT is the appropriate choice for patients with left breast cancer after breast -conserving surgery.

关 键 词：乳腺肿瘤 常规放疗 三维适形放疗 调强放疗 

分 类 号：R730.55[医药卫生—肿瘤]