Patel Rakesh R, Becker Stewart J, Das Rupak K, Mackie Thomas R
Department of Human Oncology, University of Wisconsin, Madison, WI, USA.
Int J Radiat Oncol Biol Phys. 2007 Jul 1;68(3):935-42. doi: 10.1016/j.ijrobp.2007.03.005. Epub 2007 Apr 30.
To compare dosimetrically four different techniques of accelerated partial breast irradiation (APBI) in the same patient.
Thirteen post-lumpectomy interstitial brachytherapy (IB) patients underwent imaging with preimplant computed tomography (CT) in the prone and supine position. These CT scans were then used to generate three-dimensional conformal radiotherapy (3D-CRT) and prone and supine helical tomotherapy (PT and ST, respectively) APBI plans and compared with the treated IB plans. Dose-volume histogram analysis and the mean dose (NTD(mean)) values were compared.
Planning target volume coverage was excellent for all methods. Statistical significance was considered to be a p value <0.05. The mean V100 was significantly lower for IB (12% vs. 15% for PT, 18% for ST, and 26% for 3D-CRT). A greater significant differential was seen when comparing V50 with mean values of 24%, 43%, 47%, and 52% for IB, PT, ST, and 3D-CRT, respectively. The IB and PT were similar and delivered an average lung NTD(mean) dose of 1.3 Gy(3) and 1.2 Gy(3), respectively. Both of these methods were statistically significantly lower than the supine external beam techniques. Overall, all four methods yielded similar low doses to the heart.
The use of IB and PT resulted in greater normal tissue sparing (especially ipsilateral breast and lung) than the use of supine external beam techniques of 3D-CRT or ST. However, the choice of APBI technique must be tailored to the patient's anatomy, lumpectomy cavity location, and overall treatment goals.
在同一患者中对四种不同的加速部分乳腺照射（APBI）技术进行剂量学比较。
13例保乳术后接受组织间近距离放疗（IB）的患者在俯卧位和仰卧位进行了植入前计算机断层扫描（CT）成像。然后使用这些CT扫描生成三维适形放疗（3D-CRT）以及俯卧位和仰卧位螺旋断层放疗（分别为PT和ST）的APBI计划，并与已实施的IB计划进行比较。比较剂量体积直方图分析和平均剂量（NTD(mean)）值。
所有方法的计划靶区覆盖情况均良好。统计学显著性被认为是p值<0.05。IB的平均V100显著更低（分别为12%，PT为15%，ST为18%，3D-CRT为26%）。当比较V50时，差异更显著，IB、PT、ST和3D-CRT的平均值分别为24%、43%、47%和52%。IB和PT相似，平均肺NTD(mean)剂量分别为1.3 Gy(3)和1.2 Gy(3)。这两种方法在统计学上均显著低于仰卧位外照射技术。总体而言，所有四种方法对心脏的剂量均较低且相似。
与使用仰卧位外照射技术的3D-CRT或ST相比，使用IB和PT能更好地保护正常组织（尤其是同侧乳腺和肺）。然而，APBI技术的选择必须根据患者的解剖结构、保乳术腔位置和总体治疗目标进行调整。
