Meta分析保乳术后三维适形与调强技术剂量学比较

探讨调强放疗(Intensity-modulated radiotherapy,IMRT)在早期乳腺癌放疗中的剂量学优势,以期得到有价值的循证医学证据以指导临床应用。使用计算机检索Pub Med、EMbase、Sciencedirect、中国知网、维普、万方数据库,同时辅助其它检索,收集关于早期乳腺癌保乳术后三维适形技术(Three-dimensional conformal radiotherapy,3D-CRT)与IMRT剂量学比较的文献,应用Rev Man 5.2.0软件对满足条件的15项(263例患者)数据进行Meta分析。结果表明,与3D-CRT相比,IMRT显著降低了患侧肺V20(p=0.004)、V30(p=0.008)、V40(p=0.000 8)、Dmax(p=0.001)和心脏V30(p=0.002)、V40(p=0.000 01);降低了计划靶区Dmax(p0.000 01);对V95(p=0.05)、V105(p0.000 1)、V110(p0.000 01)覆盖更好;均匀指数HI及适形指数CI也较好,p=0.02;但却增加了患侧肺V5(p=0.000 5)、V10(p=0.05),心脏V5(p0.000 1)、V10(p=0.000 7),健侧肺V5(p=0.002)、Dmen(p=0.000 4)和健侧乳腺V3(p=0.000 6)。计划靶区V100、Dmean、Dmin、患侧肺Dmean、心脏V20、Dmax、Dmean、健侧乳腺Dmean,IMRT与3D-CRT相似,差异不显著。结果提示,在早期乳腺癌保乳术后放疗中,IMRT对靶区覆盖好且剂量分布均匀,并可以减少高剂量照射区正常组织的剂量,保护正常组织,但却增加了低剂量照射区组织的剂量。

Meta-analysis of dosimetric comparision between three-dimensional conformal radiotherapy and intensity-modulated radiotherapy for breast cancer with conserving surgery

The aim was to evaluate the dosimetry superiority of IMRT (Intensity-modulated radiotherapy) in early-stage breast cancer with conserving surgery and provide more valuable evidences to the clinical researches. Clinical trials of dosimetric comparision between 3D-CRT and IMRT for early-stage breast cancer with conserving surgery were obtained from PubMed, EMbase, Sciencedirect, Wei pu, CNKI (China national knowledge Infrastructure), and Wanfang databases, which were evaluated and analyzed with the Cochrane Collaboration's RevMan 5.2.0 software. Fifteen samples were included. Compared with 3D-CRT plans, IMRT plans had a lower ipsilateral lungV20(p=0.004),V30 (p=0.008),V40(p=0.0008),Dmax(p=0.001) and heartV30(p=0.002),V40(p<0.00001), while had a higher ipsilateral lungV5(p=0.0005),V10(p=0.05) and heartV5(p<0.0001),V10(p=0.0007). IMRT plans provided a significantly better coverage of the PTVV95(p=0.05),V105(p<0.0001),V110 (p<0.00001) and maximal dose (p<0.00001). IMRT plans had a better dose homogeneity index and conformity index than 3D-CRT plans, both withp=0.02, but had a higher contralateral lungV5(p=0.002),Dmax(p=0.0004) and contralateral breastV3(p=0.0006). There was no significant difference between IMRT and 3D-CRT plans forV100, mean and minimal doses of PTV, ipsilateral lung mean dose, heartV20, maximum, mean dose, and contralateral mean dose, allp>0.05. Compared with 3D-CRT plans, IMRT plans had the dosimetry superiority for early-stage breast cancer with significantly better coverage and dose homogeneity of planning target volume while maintaining lower doses to high risk organs.