基于VMAT的乳腺癌保乳术后全乳混合调强技术的建立与评价  

Development and evaluation of whole breast irradiation with volumetric modulated arc therapy-based hybrid intensity-modulated radiotherapy after breast conserving surgery for breast cancer

作　　者：田源[1] 马攀[1] 门阔[1] 徐英杰[1] 李明辉[1] 宋一昕[1] 戴建荣[1] 

机构地区：[1]国家癌症中心/中国医学科学院肿瘤医院北京协和医学院放疗科,北京100021

出　　处：《中华放射肿瘤学杂志》2016年第7期728-732,共5页Chinese Journal of Radiation Oncology

摘　　要：目的 建立基于VMAT的乳腺癌保乳术后全乳混合调强技术并评价其临床应用价值。方法 选取10例乳腺癌保乳术后患者,分别基于固定角度IMRT的混合调强技术和基于VMAT的混合调强技术设计两组放疗计划。第1组仅以全乳作为放疗靶区,处方剂量50 Gy分25次完成;第2组以全乳及瘤床同步加量区为放疗靶区,处方剂量全乳50 Gy、瘤床同步加量区60 Gy,分25次同步完成。分别比较两组计划的剂量学参数及计划执行效率。配对t检验差异。结果 与基于固定角度IMRT的混合调强技术相比,基于VMAT的混合调强技术未能提高单纯全乳照射者靶区CI、HI值（P=0.866、0.056）,反而全面增加了OAR受量和调强野机器跳数（P=0.000~0.050和P=0.002）;但对全乳加瘤床同步加量照射患者,能减少肺受量、脊髓受量、调强野机器跳数、计划执行时间（P=0.004、0.001、0.000、0.000）。结论 对全乳加瘤床同步加量照射患者,基于VMAT的混合调强技术能更好保护OAR,提高计划执行效率,具有较高的临床应用潜力。Objective To develop whole breast irradiation with volumetric-modulated arc therapy （VMAT）-based hybrid intensity-modulated radiotherapy （IMRT） after breast conserving surgery for breast cancer, and to evaluate its value in clinical application. Methods Ten patients with breast cancer undergoing breast conserving surgery were enrolled. Two radiotherapy plans were designed based on hybrid fixed-beam IMRT/IMRT technique and hybrid VMAT/IMRT technique, respectively. One group received whole breast irradiation with a prescribed dose of 50 Gy in 25 fractions. The other group received whole breast irradiation with a prescribed dose of 50 Gy in 25 fractions, as well as simultaneous integrated boost to the tumor bed with 60 Gy in 25 fractions. The dosimetric parameters and delivery efficiency were compared between the two plans using paired t test. Results For patients treated with whole breast irradiation alone, there were no significant differences in conformity index and homogeneity index of target volume between the two plans （P=0.866,0.056）;however, compared with the hybrid fixed-beam IMRT/IMRT technique, the hybrid VMAT/IMRT technique significantly increased the doses to organs at risk （OARs） and the number of monitor units （MUs） in the intensity-modulated field （P=0.000-0.050,P=0.002）. For patients treated with whole breast irradiation with a simultaneous integrated boost to the tumor bed;however, the hybrid VMAT/IMRT technique significantly reduced the doses to the lung and spinal cord, number of MUs in intensity-modulated field, and delivery time compared with the hybrid fixed-beam IMRT/IMRT technique （P=0.004,0.001,0.000,0.000）. Conclusions For patients treated with whole breast irradiation with a simultaneous integrated boost to the tumor bed, the hybrid VMAT/IMRT technique is highly promising for clinical application due to better OAR sparing and higher delivery efficiency.

关 键 词：容积调强弧形疗法 调强放射疗法 混合调强技术 乳腺肿瘤 

分 类 号：R737.9[医药卫生—肿瘤]