Piroth Marc D, Petz Dalma, Pinkawa Michael, Holy Richard, Eble Michael J
Department of Radiation Oncology, RWTH Aachen University Hospital, Aachen, Germany.
Department of Radiation Oncology, HELIOS University Hospital Wuppertal, Witten/Herdecke University, Heusnerstr. 40, 42283, Wuppertal, Germany.
Strahlenther Onkol. 2016 Sep;192(9):609-16. doi: 10.1007/s00066-016-0981-0. Epub 2016 Jun 10.
Despite modern techniques, in some patients receiving whole breast radiotherapy (WBI) parts of the heart and the lung might receive doses which are nowadays considered relevant for the development of late morbidity. Our aim was to analyze the usefulness of a thermoplastic breast brassiere to reduce lung and heart doses.
A total of 29 patients with left-sided and 16 patients with right-sided breast cancer treated with breast conserving surgery and WBI between 2012 and 2013 were included in a prospective study analyzing the effectiveness of a thermoplastic breast bra. WBI was performed using 3D tangential fields up to 50.4 Gy. Treatment planning was performed with and without bra. Several dosimetrical parameters were analyzed comparatively focusing on the heart and ipsilateral lung. For heart dose comparisons, subvolumes like the left anterior descending artery (LAD) and a defined apical region, so-called "apical myocardial territory" (AMT), were defined.
By using the bra, the mean lung dose was reduced by 30.6 % (left-sided cancer) and 29.5 % (right-sided; p < 0.001). The V20Gy for the left lung was reduced by 39.5 % (4.9 vs. 8.1 % of volume; p < 0.001). The mean and maximum heart doses were significantly lower (1.6 vs. 2.1 Gy and 30.7 vs. 39.3 Gy; p = 0.01 and p < 0.001), which also applies to the mean and maximum dose for the AMT (2.5 vs. 4.4 Gy and 31.0 vs. 47.2 Gy; p < 0.01 and p < 0.001). The mean and maximum dose for LAD was lower without reaching significance. No acute skin toxicities > grade 2 were observed.
By using a thermoplastic breast bra, radiation doses to the heart and especially parts of the heart apex and ipsilateral lung can be significantly lowered without additional skin toxicity.
尽管有现代技术，但在一些接受全乳放疗（WBI）的患者中，心脏和肺部的部分区域可能会接受如今被认为与晚期并发症发生相关的剂量。我们的目的是分析热塑性乳房胸罩在降低肺部和心脏剂量方面的有效性。
2012年至2013年间，共有29例左侧乳腺癌患者和16例右侧乳腺癌患者接受了保乳手术及WBI，并纳入一项前瞻性研究，分析热塑性乳房胸罩的有效性。WBI采用三维切线野进行，剂量达50.4 Gy。分别在有胸罩和无胸罩的情况下进行治疗计划。比较分析了几个剂量学参数，重点关注心脏和同侧肺部。为进行心脏剂量比较，定义了左前降支（LAD）和一个特定的心尖区域，即所谓的“心尖心肌区域”（AMT）等子体积。
使用胸罩后，平均肺部剂量降低了30.6%（左侧乳腺癌）和29.5%（右侧乳腺癌；p < 0.001）。左肺的V20Gy降低了39.5%（4.9%对8.1%的体积；p < 0.001）。平均心脏剂量和最大心脏剂量显著降低（1.6 Gy对2.1 Gy以及30.7 Gy对39.3 Gy；p = 0.01和p < 0.001），这也适用于AMT的平均剂量和最大剂量（2.5 Gy对4.4 Gy以及31.0 Gy对47.2 Gy；p < 0.01和p < 0.001）。LAD的平均剂量和最大剂量较低，但未达到显著差异。未观察到大于2级的急性皮肤毒性。
使用热塑性乳房胸罩可显著降低心脏尤其是心尖部分和同侧肺部的辐射剂量，且无额外的皮肤毒性。
