作 者: (高瀚); (贾鹏飞); (陈炳森); (汤乐民);
机构地区: 南通大学医学院,226001
出 处: 《中华放射肿瘤学杂志》 2017年第9期1055-1061,共7页
摘 要: 目的 对食管癌VMAT与IMRT靶区和OAR剂量比较行Meta分析。方法 文献检索纳入相关研究,分析靶区和OAR剂量参数、机器跳数及治疗时间。结果 17项研究的323病例纳入Meta分析。VMAT计划中GTV的Dmean、在总剂量≤50.4 Gy时PTV的Dmean和在总剂量〉50.4 Gy时PTV的Dmax优于IMRT (P=0.009、0.043、0.039)。心脏Dmean、V30、V40,脊髓Dmax,肺V5、V10、Dmean差异均无统计学意义(P〉0.05);VMAT计划中肺的V15、V20、V30优于IMRT计划(P=0.001、0.000、0.023)。VMAT计划中单次照射1.8、2.0 Gy的机器跳数较IMRT计划分别减少275.4、134.2 MU (P=0.000、0.022);VMAT计划中单次照射1.8、2.0 Gy的TT比IMRT计划分别缩短323.5、193.7 s (P=0.000、0.009)。结论 VMAT计划能显著减少TT和机器跳数、提高设备使用率,降低肺受照剂量和RP发生风险。VMAT与IMRT相比在照射总剂量≤50.4 Gy时除PTV的Dmean和GTV的Dmean、Dmax外,靶区其他剂量参数均无明显优势。对脊髓和心脏保护VMAT也无明显优势。 Objective To investigate the dosimetric comparison of target volumes and organs at risk (OAR) between volumetric-modulated arc therapy (VMAT) and intensity-modulated radiotherapy (IMRT) for esophageal cancer by a meta-analysis. Methods A literature search was performed to collect the clinical studies on dosimetric comparison between VMAT and IMRT. The primary endpoints of interest were dosimetric parameters of target volumes and OAR, number of monitor units (MUs), and treatment time (TT). Results A total of 17 studies involving 323 patients were included in this meta-analysis. When the total dose was〉50.4 Gy, VMAT showed significantly lower mean dose (Dmean) of gross tumor volume (GTV) and maximum dose (Dmax) of planning target volume (PTV) than IMRT (P=0.009;P=0.039). There were no significant differences in Dmean, V30, and V40 of the heart, Dmax of the spinal cord, and V5, V10, and Dmean of the lung between VMAT and IMRT (P〉0.05). VMAT showed significantly lower V15, V20, and V30 of the lung than IMRT (P=0.001;P=0.000;P=0.023). When the single dose was 1.8 Gy and 2.0 Gy, VMAT showed significantly lower TT (reduced by 323.5 s and 193.7 s) and number of MUs (reduced by 275.4 MU and 134.2 MU) than IMRT (P=0.000 and 0.009;P=0.000 and 0.022). Conclusions VMAT can significantly reduce TT, MUs, irradiation dose to the lung, and the risk of radiation pneumonitis, and improve the utilization rate of equipment. Compared with IMRT, VMAT has no significant advantages in protection of the spinal cord and the heart and dosimetric parameters of target volumes except Dmean of PTV and Dmean and Dmax of GTV when the total dose was ≤50.4 Gy.