Mast Mirjam E, van Kempen-Harteveld Loes, Heijenbrok Mark W, Kalidien Yamoena, Rozema Hans, Jansen Wim P A, Petoukhova Anna L, Struikmans Henk
Radiotherapy Centre West, The Hague, The Netherlands.
Radiother Oncol. 2013 Aug;108(2):248-53. doi: 10.1016/j.radonc.2013.07.017. Epub 2013 Sep 14.
In radiotherapy for left-sided breast cancer, Active Breathing Control enables a decrease of cardiac and Left Anterior Descending (LAD) coronary artery dose. We compared 3D-Conformal (3D-CRT) to Intensity Modulated Radiotherapy (IMRT) treatment plans based on free-breathing (FB) and breath-hold (BH). We investigated whether IMRT enables an additional decrease of cardiac dose in radiotherapy plans with and without BH.
Twenty patients referred for whole breast irradiation were included. The whole breast, heart and LAD-region were contoured. Four treatment plans were generated: FB_3D-CRT; FB_IMRT; BH_3D-CRT; BH_IMRT. Several doses were obtained from Dose Volume Histograms and compared. Results were compared statistically using the Wilcoxin Signed Rank Test. For heart and LAD-region, a significant dose reduction was found in BH (p<0.01). For both BH and FB, a significant dose reduction was found using IMRT (p<0.01). By using IMRT an average reduction of 5% was noted in the LAD-region for the volume receiving 20Gy. In 5 cases, the LAD-region remained situated in the vicinity of the radiation portals even in BH. Nevertheless, with IMRT the LAD dose was reduced in these cases.
IMRT results in a significant additional decrease of dose in the heart and LAD-region in both breath-hold and free-breathing.
在左侧乳腺癌放疗中，主动呼吸控制可降低心脏和左前降支（LAD）冠状动脉的剂量。我们比较了基于自由呼吸（FB）和屏气（BH）的三维适形放疗（3D-CRT）与调强放疗（IMRT）治疗计划。我们研究了在有或没有屏气的放疗计划中，IMRT是否能进一步降低心脏剂量。
纳入20例接受全乳照射的患者。勾勒出全乳、心脏和LAD区域。生成了四个治疗计划：FB_3D-CRT；FB_IMRT；BH_3D-CRT；BH_IMRT。从剂量体积直方图中获取了几个剂量并进行比较。使用Wilcoxin符号秩检验对结果进行统计学比较。对于心脏和LAD区域，屏气时剂量显著降低（p<0.01）。对于屏气和自由呼吸，使用IMRT时剂量均显著降低（p<0.01）。使用IMRT时，接受20Gy剂量的LAD区域平均减少了5%。在5例病例中，即使在屏气时LAD区域仍位于放射野附近。然而，使用IMRT时这些病例中的LAD剂量降低了。
IMRT在屏气和自由呼吸时均能显著进一步降低心脏和LAD区域的剂量。
