Abstract Objective To compare the dosimetric effects of simulation and correction fusion (SF), automatic and visual correction fusion (AF), and bone fusion (BF) during the course of intensity-modulated radiotherapy (IMRT) for nasopharyngeal carcinoma (NPC). Methods Fifteen patients with stage III-IVa NPC treated with IMRT had planning CT scans before and after 20-25 fractions of radiotherapy. SF, AF, and PF methods were separately used to undertake the fusion between the first and second planning CT images. New treatment isocenters were the shadow cast of the initial isocenter on the second planning CT images with the three fusion methods;initial treatment planning was transferred to the second planning CT according the new treatment isocenter, and new dosimetric distribution was calculated. The fusion parameters of the three fusion methods, as well as dosimetric changes in the target volume and normal tissue, were compared with paired t-test. Results There were relatively small differences in fusion parameters between SF and AF methods;the paired difference means in translation in all directions were less than 0.13 cm, and the paired difference means in rotation in all directions were less than 0.40 degree. BF fusion parameters differed widely from others, especially in rotation, and the paired difference means were more than 0.71 degree. The three fusion methods have similar dosimetric effects on the target volume and normal tissue,but had a significant dosimetric effect on the neck region, with a significant decrease in GTVnd D95(P=0.039). Dmax and D1 cm3 for the brain stem remained unchanged or showed an increasing trend with the BF method, but they showed a decreasing trend with the SF and AF methods. Conclusions Different fusion methods would lead to different results in the research on dosimetric changes in the target volume and normal tissueduring the IMRT for NPC, so the fusion method should be introduced in the reports of these research. TheBF method is not recommended because its dosimetric effect on the neck region is great, resulting in a big DOI:10.3760/cma.j.issn.1004-4221.2015.03.018 基金项目:北京希望马拉松专项基金资助(LC2012B36) 作者单位:100021 北京协和医学院 中国医学科学院肿瘤医院放疗科 通信作者:高黎,Email:li_gao2008@outlook.comdifference from the actual dose distribution. The SF and AF methods have similar dosimetric effects, which are close to the actual situation.
. Dosimetric effects of different fusion methods during intensity-modulated radiotherapy for nasopharyngeal carcinoma[J]. Chinese Journal of Radiation Oncology, 2015, 24(3): 301-305.
. Dosimetric effects of different fusion methods during intensity-modulated radiotherapy for nasopharyngeal carcinoma[J]. Chinese Journal of Radiation Oncology, 2015, 24(3): 301-305.
[1] 黄劭敏,邓小武,赵充,等.鼻咽癌调强放疗中解剖结构改变对剂量分布影响研究[J].中华放射肿瘤学杂志,2010,19(5):404-408.DOI:10.3760/cma.j.issn.1004-4221.2010.05.005. [2] 曹建忠,罗京伟,徐国镇,等.鼻咽癌调强放疗中解剖及剂量学改变再次计划必要性研究[J].中华放射肿瘤学杂志,2008,17(2):161-164. [3] Zhang X, Li M, Cao J, et al. Dosimetric variations of target volumes and organs at risk in nasopharyngeal carcinoma intensity-modulated radiotherapy[J]. Br J Radiol,2012,85(1016):e506-513.DOI:10.1259/bjr/20695672. [4] Chen C, Fei Z, Chen L, et al. Will weight loss cause significant dosimetric changes of target volumes and organs at risk in nasopharyngeal carcinoma treated with intensity-modulated radiation therapy?[J]. Med Dosim,2014,39(1):34-37.DOI:10.1016/j.meddos.2013.09.002. [5] Wang RH, Zhang SX, Zhou LH, et al. Volume and dosimetric variations during two-phase adaptive intensity-modulated radiotherapy for locally advanced nasopharyngeal carcinoma[J]. Biomed Mater Eng,2014,24(1):1217-1225.DOI:10.3233/BME-130923. [6] Yang H, Hu W, Ding W, et al. Changes of the transverse diameter and volume and dosimetry before the 25th fraction during the course of intensity-modulated radiation therapy (IMRT) for patients with nasopharyngeal carcinoma[J]. Med Dosim,2012,37(2):225-229.DOI:10.1016/j.meddos.2011.08.003. [7] 中国鼻咽癌临床分期工作委员会.鼻咽癌′92分期修订工作报告[J].中华放射肿瘤学杂志,2009,18(1):2-6.DOI:10.3760/cma.j.issn.1004-4221.2009.01.001. [8] 易俊林,高黎,徐国镇,等.鼻咽癌调强放射治疗靶区勾画-中国医学科学院肿瘤医院经验总结[J].肿瘤预防与治疗,2011,24(3):157-163,172.DOI:10.3969/j.issn.1674-0904.2011.03.006. [9] Hansen EK, Bucci MK, Quivey JM, et al. Repeat CT imaging and replanning during the course of IMRT for head-and-neck cancer[J]. Int J Radiat Oncol Biol Phys,2006,64(2):355-362. [10] 胡炜,丁维军,杨海华,等.鼻咽癌调强放疗中的剂量学研究[J].中华放射肿瘤学杂志,2008,17(6):480-481.DOI:10.3760/cma.j.issn.1004-4221.2008.06.023. [11] 卢洁,尹勇,范廷勇,等.鼻咽癌调强放疗中实施同一计划对剂量的影响[J].中华放射医学与防护杂志,2008,28(6):456-458. [12] Wang W,Yang H, Hu W, et al. Clinical study of the necessity of replanning before the 25th fraction during the course of intensity-modulated radiotherapy for patients with nasopharyngeal carcinoma[J]. Int J Radiat Oncol Biol Phys,2010,77(2):617-621.DOI:10.1016/j.ijrobp.2009.08.036. [13] Wang X, Lu J, Xiong X, et al. Anatomic and dosimetric changes during the treatment course of intensity-modulated radiotherapy for locally advanced nasopharyngeal carcinoma[J]. Med Dosim,2010,35(2):151-157.DOI:10.1016/j.meddos.2009.06.007. [14] 龚伟,楚建军,杨波,等.利用DVH图分析鼻咽癌调强放疗中正常器官体积剂量的变化[J].现代肿瘤医学,2010,18(9):1726-1728.DOI:10.3969/j.issn.1672-4992.2010.09.18. [15] 杨海华,胡炜,丁维军,等.鼻咽癌调强放疗过程中再次计划实施必要性的临床研究[J].中华放射肿瘤学杂志,2010,19(3):189-190.DOI:10.3760/cma.j.issn.1004-4221.2010.03.004. [16] 张希梅,李明辉,曹建忠,等.鼻咽癌调强放疗中靶区剂量变化规律研究[J].中华放射肿瘤学杂志,2010,19(3):197-200.DOI:10.3760/cma.j.issn.1004-4221.2010.03.006. [17] Zhao L, Wan Q, Zhou Y, et al. The role of replanning in fractionated intensity modulated radiotherapy for nasopharyngeal carcinoma[J].Radiother Oncol,2011,98(1):23-27.DOI:10.1016/j.radonc.2010.10.009. [18] 卢洁,马一栋,尹勇,等.基于形变配准的鼻咽癌调强放射治疗计划剂量学研究[J].中华放射医学与防护杂志,2011,31(5):575-578.DOI:10.3760/cma.j.issn.0254-5098.2011.05.018. [19] 彭倩,黎杰,冯梅,等.鼻咽癌调强放疗过程中进行计划调整后的剂量分析[J].肿瘤预防与治疗,2011,24(1):14-17.DOI:10.3969/j.issn.1674-0904.2011.01.004. [20] 王震吾,王明智,杨波,等.鼻咽癌调强适形放疗中正常器官体积剂量变化的研究[J].实用临床医药杂志,2011,15(1):62-66.DOI:10.3969/j.issn.1672-2353.2011.01.017. [21] 魏青,钱普东,蒋明华,等.鼻咽癌调强放疗过程中剂量变化的分析[J].临床肿瘤学杂志,2011,16(7):626-629.DOI:10.3969/j.issn.1009-0460.2011.07.012. [22] Cheng HC, Wu VW, Ngan RK, et al. A prospective study on volumetric and dosimetric changes during intensity-modulated radiotherapy for nasopharyngeal carcinoma patients[J]. Radiother Oncol,2012,104(3):317-323.DOI:10.1016/j.radonc.2012.03.013. [23] 王微,杨海华,单国平,等.鼻咽癌在调强放射治疗15次和25次时重新计划时机的研究[J].肿瘤学杂志,2012,18(1):10-14. [24] Lu J, Ma Y, Chen J, et al. Assessment of anatomical and dosimetric changes by a deformable registration method during the course of intensity-modulated radiotherapy for nasopharyngeal carcinoma[J]. J Radiat Res,2014,55(2):97-104.DOI:10.1093/jrr/rrt076. [25] Ren G, Xu SP, Du L, et al. Actual anatomical and dosimetric changes of parotid glands in nasopharyngeal carcinoma patients during intensity modulated radiation therapy[J/OL]. Bio Med Res Int,2015,2015:670327[2015-03-20].http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4352457/.DOI:10.1155/2015/670327. [26] Wang W, Yang H, Mi Y, et al. Rules of parotid gland dose variations and shift during intensity modulated radiation therapy for nasopharyngeal carcinoma[J/OL]. Radiat Oncol,2015,10(1):3[2015-03-20].http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4298965/. [27] Yan D, Yan S, Wang Q, et al. Predictors for replanning in loco-regionally advanced nasopharyngeal carcinoma patients undergoing intensity-modulated radiation therapy:a prospective observational study[J/OL]. BMC Cancer,2013,13:548[2015-03-20].http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3840644/.DOI:10.1186/1471-2407-13-548.
2015, Vol. 24 
