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早期NSCLC无均整器模式VMAT计划剂量比较研究
李定杰,张有改,薛莹,郭伟,葛红,王建华
450008 郑州,河南省肿瘤医院放疗科
The comparison of plan dose and dose verification in volumetric modulated arc therapy for early stage non-small cell lung cancer with non-flattening filter
Li Dingjie,Zhang Yougai,Xue Ying,Guo Wei,Ge Hong,Wang Jianhua
Department of Radiation Oncology,Henan Cancer Hospital,Zhengzhou 450008,China
Objective To compare the dose distributions of the volumetric modulated arc therapy (VMAT) for early stage non-small cell lung cancer (NSCLC) using conventional flattening filter (FF) and the flattening filter free (FFF) beams and to verify the dose calculation accuracy of the FFF beam through a three-dimensional verification system. Methods The treatment plans of 20 patients (2015 years hospitalized) treated with SBRT for early stage NSCLC using a TrueBeam accelerator were retrospectively analyzed. The patients were scanned with 4DCT and the average density projection images were used for organ segmentation and treatment planning using an Eclipse plan system. Two volumetric modulated arc therapy (VMAT) plans with FF and FFF were designed with the same planning parameters for each patient. The dose distributions between the two plans were compared and their dose verifications were assessed with the ArcCheck device. Results With the same dose coverage for the target,there was no significant difference in the dose compatibility index 100%(CI100%) between FF and FFF beams (P=0.82).CI80% and CI50% of FFF plan were lower than that of FF plan (P=0.02,0.01).The dose significantly decreased in the FFF plan comparing with the FF plan for the ipsilateral lung and the total lung (P<0.01 for both).There was no significant difference between monitor units of the FF and FFF plans (P=0.34),while the delivery time of FFF was significant shorter than that of FF (P<0.01).The DVH passing,γ pass rates and the absolute dose deviations of the FF and FFF plans at the central point were not significantly different (P=0.05,0.16,0.26). Conclusions FFF beams for NSCLC patients with VMAT planning can significantly improve the dose distribution compatibility and reduce radiation doses to lung. The beam delivery with FFF beams was also faster. Furthermore,the three-dimensional dose verification confirmed that the dose calculation in Eclipse plan system using FFF beams for VMAT plans were accurate and met the clinical need.
Li Dingjie,Zhang Yougai,Xue Ying et al. The comparison of plan dose and dose verification in volumetric modulated arc therapy for early stage non-small cell lung cancer with non-flattening filter[J]. Chinese Journal of Radiation Oncology, 2017, 26(1): 53-56.
[1] Onishi H,Shirato H,Nagata Y,et al. Stereotactic body radiotherapy (SBRT) for operable stage Ⅰ non-small-cell lung Cancer:can SBRT be comparable to surgery?[J].Int J Radiat Oncol Biol Phys,2011,81(5):1352-1358.DOI:10.1016/j.ijrobp.2009.07.1751.
[2] Haasbeek CJ,Lagerwaard FJ,Solotman BJ,et al. Outcomes of stereotactic ablative radiotherapy for centrally located early-stage lung Cancer[J].J Thorac Oncol,2011,6(12):2036-2043.DOI:10.1097/JTO.0b013e31822e71 d8.
[3] Takeda A,Kunieda E,Sanuki N,et al. Stereotactic body radiotherapy (SBRT) for solitary pulmonary nodules clinically diagnosed as lung Cancer with no pathological confirmation:comparison with non-small-cell lung Cancer[J].Lung Cancer,2012,77(1):77-82.DOI:10.1016/j.lungcan.2012.01.006.
[4] Vassiliev ON,Kry SF,Chang JY,et al. Stereotactic radiotherapy for lung cancer using a flattening filter free Clinac[J].J Appl Clin Med Phys,2009,10(1):14-21.
[5] Navarria P,Ascolese AM,Mancosu P,et al. Volumetric modulated arc therapy with flattening filter free (FFF) beams for stereotactic body radiation therapy (SBRT) in patients with medically inoperable early stage non small cell lung cancer (NSCLC)[J].Radiother Oncol,2013,107(3):414-418.DOI:10.1016/j.radonc.2013.04.016.
[6] Lechner W,Kragl G,Georg D.Evaluation of treatment plan quality of IMRT and VMAT with and without flattening filter using Pareto optimal fronts[J].Radiother Oncol,2013,109(3):437-441.DOI:10.1016/j.radonc.2013.09.020.
[7] Lang S,Shrestha B,Graydon B,et al. Clinical application of flattening filter free beams for extracranial stereotactic radiotherapy[J].Radiother Oncol,2013,106(2):255-259.DOI:10.1016/j.radonc.2012.12.012.
[8] 于金明,谢鹏,邢力刚.Ⅰ期NSCLC立体定向放射治疗研究进展[J].癌症进展,2011,9(6):617-619.DOI:10.3969/j.issn.1672-1535.2011.06.006.
Yu JM,Xie P,Xing LG.Stereotactic radiotherapy for stage Ⅰ non-small cell lung cancer research progress[J].Oncol Prog,2011,9(6):617-619.DOI:10.3969/j.issn.1672-1535.2011.06.006.
[9] Yamashita H,Nakagawa K,Nakamura N,et al. Exceptionally high incidence of symptomatic grade 2-5 radiation pneumonitis after stereotactic radiation therapy for lung tumors[J].Radiat Oncol,2007,2:21.DOI:10.1186/1748-717X-2-21.
[10] Kragl G,Baier F,Lutz S,et al. Flattening filter free beams in SBRT and IMRT:dosimetric assessment of peripheral doses[J].Z Med Phys,2011,21(2):91-101.DOI:10.1016/j.zemedi.2010.07.003.
[11] Hrbacek J,Lang S,Graydon SN,et al. Dosimetric comparison of flattened and unflattened beams for stereotactic ablative radiotherapy of stage Ⅰ non-small cell lung cancer[J].Med Phys,2014,41(3):031709.DOI:10.1118/1.4866231.
[12] 陈阿龙,陈立新,陈利,等.基于三维影像解剖结构的调强剂量验证的初步研究[J].中华放射肿瘤学杂志,2014,23(4):352-356.DOI:10.3760/cma.j.issn.1004-4221.2014.04.019.
Chen AL,Chen LX,Chen L,et al. A primary research of intensity-modulated dose verification based on anatomic structure of three-dimensional images[J].Chin J Radiat Oncol,2014,23(4):352-356.DOI:10.3760/cma.j.issn.1004-4221.2014.04.019.