Boman Eeva, Rossi Maija, Haltamo Mikko, Skyttä Tanja, Kapanen Mika
Department of Oncology, Tampere University Hospital, PO BOX 2000, FI-33521 Tampere, Finland; Department of Medical Physics, Tampere University Hospital, PO BOX 2000, FI-33521 Tampere, Finland; Department of Radiation Oncology, Wellington Blood and Cancer Centre, Wellington Hospital, Wellington 6242, New Zealand.
Department of Oncology, Tampere University Hospital, PO BOX 2000, FI-33521 Tampere, Finland; Department of Medical Physics, Tampere University Hospital, PO BOX 2000, FI-33521 Tampere, Finland.
Phys Med. 2016 Oct 28. doi: 10.1016/j.ejmp.2016.10.012.
To investigate different volumetric modulated arc therapy (VMAT) field designs for lymph node positive breast cancer patients when compared to conventional static fields and standard VMAT designs.
Nineteen breast cancer patients with lymph node involvement (eleven left and eight right sided) were retrospectively analyzed with different arc designs. Proposed split arc designs with total rotations of 2×190° and 2×240° were compared to conventional field in field (FinF) and previously published non-split arc techniques with the same amount of total rotations.
All VMAT plans were superior in dose conformity, when compared to the FinF plans. Split arc design decreased significantly ipsilateral lung dose and heart V5Gy for both left and right sided cases, when compared to non-split VMAT designs. For left sided cases no significant differences were seen in contralateral lung mean dose or V5Gy between different VMAT designs. For right sided cases the contralateral lung dose V5Gy was significantly higher in split VMAT group, when compared to non-split VMAT designs. The contralateral breast dose V5Gy increased significantly for split VMAT plans for both sides, when compared to non-split VMAT designs or FinF plans.
The proposed split VMAT technique was shown to be superior to previously published non-split VMAT and conventional FinF techniques significantly reducing dose to the ipsilateral lung and heart. However, this came with the expense of an increase in the dose to the contralateral breast and for right-sided cases to the contralateral lung.
与传统静态野和标准容积调强弧形治疗（VMAT）设计相比，研究淋巴结阳性乳腺癌患者的不同VMAT野设计。
对19例有淋巴结受累的乳腺癌患者（11例左侧，8例右侧）采用不同的弧形设计进行回顾性分析。将提议的总旋转角度为2×190°和2×240°的分割弧形设计与传统的野中野（FinF）以及先前发表的总旋转角度相同的非分割弧形技术进行比较。
与FinF计划相比，所有VMAT计划在剂量适形性方面均更优。与非分割VMAT设计相比，分割弧形设计在左侧和右侧病例中均显著降低了同侧肺剂量和心脏V5Gy。对于左侧病例，不同VMAT设计之间在对侧肺平均剂量或V5Gy方面未见显著差异。对于右侧病例，与非分割VMAT设计相比，分割VMAT组的对侧肺剂量V5Gy显著更高。与非分割VMAT设计或FinF计划相比，两侧分割VMAT计划的对侧乳腺剂量V5Gy均显著增加。
提议的分割VMAT技术被证明优于先前发表的非分割VMAT和传统FinF技术，可显著降低同侧肺和心脏的剂量。然而，这是以对侧乳腺剂量增加以及右侧病例对侧肺剂量增加为代价的。
