Department of Radiation Oncology, Charité School of Medicine and University Hospital Berlin, Berlin, Germany.
Br J Radiol. 2013 Dec;86(1032):20130515. doi: 10.1259/bjr.20130515. Epub 2013 Oct 28.
To test the feasibility of volumetric modulated arc therapy (VMAT) in breast cancer and to compare it with three-dimensional conformal radiotherapy (3D-CRT) as conventional tangential field radiotheraphy (conTFRT).
12 patients (Stage I, 8: 6 left breast cancer and 2 right breast cancer; Stage II, 4: 2 on each side). Three plans were calculated for each case after breast-conserving surgery. Breast was treated with 50 Gy in four patients with supraclavicular lymph node inclusion, and in eight patients without the node inclusion. Multiple indices and dose parameters were measured.
V95% was not achieved by any modality. Heterogeneity index: 0.16 (VMAT), 0.13 [intensity-modulated radiotherapy (IMRT)] and 0.14 (conTFRT). Conformity index: 1.06 (VMAT), 1.15 (IMRT) and 1.69 (conTFRT). For both indices, IMRT was more effective than VMAT (p=0.009, p=0.002). Dmean and V20 for ipsilateral lung were lower for IMRT than VMAT (p=0.0001, p=0.003). Dmean, V2 and V5 of contralateral lung were lower for IMRT than VMAT (p>0.0001, p=0.005). Mean dose and V5 to the heart were lower for IMRT than for VMAT (p=0.015, p=0.002).
The hypothesis of equivalence of VMAT to IMRT was not confirmed for planning target volume parameter or dose distribution to organs at risk. VMAT was inferior to IMRT and 3D-CRT with regard to dose distribution to organs at risk, especially at the low dose level.
New technology VMAT is not superior to IMRT or conventional radiotherapy in breast cancer in any aspect.
验证容积旋转调强放疗（VMAT）在乳腺癌治疗中的可行性，并将其与传统切线野放疗（conTFRT）进行比较。
12 例患者（Ⅰ期 8 例：左侧乳腺癌 6 例，右侧乳腺癌 2 例；Ⅱ期 4 例：双侧各 2 例）。保乳手术后，为每位患者计算了 3 种计划。4 例锁骨上淋巴结阳性患者乳腺给予 50Gy 照射，8 例无淋巴结阳性患者乳腺未照射。测量了多个指标和剂量参数。
任何模式都未达到 V95%。不均匀性指数：0.16（VMAT）、0.13（调强放疗，IMRT）和 0.14（conTFRT）。适形性指数：1.06（VMAT）、1.15（IMRT）和 1.69（conTFRT）。对于这两个指数，IMRT 比 VMAT 更有效（p=0.009，p=0.002）。同侧肺的 Dmean 和 V20 低于 IMRT（p=0.0001，p=0.003）。IMRT 比 VMAT 降低了对侧肺的 Dmean、V2 和 V5（p>0.0001，p=0.005）。IMRT 比 VMAT 降低了心脏的平均剂量和 V5（p=0.015，p=0.002）。
对于计划靶区参数或危及器官的剂量分布，VMAT 与 IMRT 等效的假设没有得到证实。VMAT 在危及器官的剂量分布方面逊于 IMRT 和 3D-CRT，特别是在低剂量水平。
新技术 VMAT 在乳腺癌的任何方面都不优于 IMRT 或常规放疗。
