PDF(Pubmed)
Abstract：
OBJECTIVE: To compare implant sparing irradiation with conventional radiotherapy (RT) using helical (H) and TomoDirect (TD) techniques in breast cancer patients undergoing immediate breast reconstruction (IBR).
METHODS: The dosimetric parameters of 40 patients with retropectoral implants receiving 50.4 Gy delivered in 28 fractions were analyzed. Three plans were created: H plan using conventional planning target volume (PTV) that included the chest wall, skin, and implant; TD plan using conventional PTV; and Hs plan using implant-sparing PTV. The H, TD, and Hs plans were compared for PTV doses, organ-at-risk (OAR) doses, and treatment times.
RESULTS: Dose distribution in the Hs plan was less homogeneous and uniform than that in the H and TD plans. The TD plan had lower lung, heart, contralateral breast, spinal cord, liver, and esophagus doses than the Hs plan. Compared to the Hs plan, the H plan had lower lung volume receiving 5Gy (V5) (39.1±3.9 vs. 41.2±3.9 Gy; p<0.001), higher V20 (12.3±1.3 vs. 11.5±2.6 Gy; p=0.02), and higher V30 (7.5±1.6 vs. 4.4±1.7 Gy; p<0.001). H plan outperformed Hs plan in heart dosimetric parameters except V20. The Hs plan had significantly lower mean implant doses (43.4±2.1 Gy) than the H plan (51.4±0.5 Gy; p<0.001) and the TD plan (51.9±0.6 Gy; p<0.001). Implementing an implant sparing technique for silicone dose reduction decreases lung doses.
CONCLUSIONS: Conventional H and TD plans outperform the implant sparing helical plan dosimetrically. Because capsular contracture during RT is unpredictable, long-term clinical outcomes are required to determine whether silicon should be spared.
METHODS: The dosimetric parameters of 40 patients with retropectoral implants receiving 50.4 Gy delivered in 28 fractions were analyzed. Three plans were created: H plan using conventional planning target volume (PTV) that included the chest wall, skin, and implant; TD plan using conventional PTV; and Hs plan using implant-sparing PTV. The H, TD, and Hs plans were compared for PTV doses, organ-at-risk (OAR) doses, and treatment times.
RESULTS: Dose distribution in the Hs plan was less homogeneous and uniform than that in the H and TD plans. The TD plan had lower lung, heart, contralateral breast, spinal cord, liver, and esophagus doses than the Hs plan. Compared to the Hs plan, the H plan had lower lung volume receiving 5Gy (V5) (39.1±3.9 vs. 41.2±3.9 Gy; p<0.001), higher V20 (12.3±1.3 vs. 11.5±2.6 Gy; p=0.02), and higher V30 (7.5±1.6 vs. 4.4±1.7 Gy; p<0.001). H plan outperformed Hs plan in heart dosimetric parameters except V20. The Hs plan had significantly lower mean implant doses (43.4±2.1 Gy) than the H plan (51.4±0.5 Gy; p<0.001) and the TD plan (51.9±0.6 Gy; p<0.001). Implementing an implant sparing technique for silicone dose reduction decreases lung doses.
CONCLUSIONS: Conventional H and TD plans outperform the implant sparing helical plan dosimetrically. Because capsular contracture during RT is unpredictable, long-term clinical outcomes are required to determine whether silicon should be spared.
摘要：
目的：比较使用螺旋（H）和TomoDirect（TD）技术在接受即时乳房重建（IBR）的乳腺癌患者中植入保留照射与常规放疗（RT）。
方法：分析了40例接受50.4Gy分28次递送的胸肌后植入物患者的剂量学参数。创建了三个计划：H计划使用包括胸壁在内的常规计划目标体积（PTV），皮肤,和植入；使用常规PTV的TD计划；和使用植入备用PTV的Hs计划。H,TD,并比较了PTV剂量的Hs计划，危险器官(OAR)剂量，和治疗时间。
结果：与H和TD计划相比，Hs计划中的剂量分布不那么均匀和均匀。TD计划有下肺，心,对侧乳房，脊髓,肝脏,和食道剂量比Hs计划。与HS计划相比，H计划有较低的肺容量接受5Gy（V5）（39.1±3.9vs.41.2±3.9Gy；p<0.001），更高的V20（12.3±1.3vs.11.5±2.6Gy；p=0.02），和更高的V30(7.5±1.6vs.4.4±1.7Gy；p<0.001）。除V20外，H计划在心脏剂量参数方面优于Hs计划。Hs计划的平均植入剂量(43.4±2.1Gy)显著低于H计划(51.4±0.5Gy;p<0.001)和TD计划(51.9±0.6Gy;p<0.001)。实施用于减少硅酮剂量的植入物节约技术减少肺剂量。
结论：常规H和TD计划在剂量上优于植入物保留螺旋计划。因为RT期间包膜挛缩是不可预测的，需要长期的临床结局来确定是否应该保留硅.
方法：分析了40例接受50.4Gy分28次递送的胸肌后植入物患者的剂量学参数。创建了三个计划：H计划使用包括胸壁在内的常规计划目标体积（PTV），皮肤,和植入；使用常规PTV的TD计划；和使用植入备用PTV的Hs计划。H,TD,并比较了PTV剂量的Hs计划，危险器官(OAR)剂量，和治疗时间。
结果：与H和TD计划相比，Hs计划中的剂量分布不那么均匀和均匀。TD计划有下肺，心,对侧乳房，脊髓,肝脏,和食道剂量比Hs计划。与HS计划相比，H计划有较低的肺容量接受5Gy（V5）（39.1±3.9vs.41.2±3.9Gy；p<0.001），更高的V20（12.3±1.3vs.11.5±2.6Gy；p=0.02），和更高的V30(7.5±1.6vs.4.4±1.7Gy；p<0.001）。除V20外，H计划在心脏剂量参数方面优于Hs计划。Hs计划的平均植入剂量(43.4±2.1Gy)显著低于H计划(51.4±0.5Gy;p<0.001)和TD计划(51.9±0.6Gy;p<0.001)。实施用于减少硅酮剂量的植入物节约技术减少肺剂量。
结论：常规H和TD计划在剂量上优于植入物保留螺旋计划。因为RT期间包膜挛缩是不可预测的，需要长期的临床结局来确定是否应该保留硅.
