Abstract：Objective To study the PTV by ng 4DCT and compare target, target displacement and dose distribution of 3D and 4D planning for thoracic middle or lower esophageal cancer, evaluate the clinical value of 4DCT in esophageal cancer radiotherapy. Methods From Jan to Dec 2012patients with primary esophageal cancer underwent 3DCT simulation scans first, then followed by 4DCT simulation scan. PTV and OARs were sketched in the ordinary 3DCT and 4DCT respectively. And designing two sets of radiotherapy plan for each patient:3D and 4D plan. We compare PTV, PTV displacement and OARs dosimetry′s differences in the 3D plan and 4D plan. Using the paired t-test or Wilcoxon sign-rank test to compare the difference between the two sets of plans. Results The volume of PTV4D was larger than the PTV3D (195.19 cm3vs.175.67 cm3,P=0.001) in all patients. The center displacement had only significantly difference (displacement was 0.25 cm,P=0.014) in left-right direction for 10 patients of thoracic middle esophageal cancer. The center displacement had no significantly different in the three direction for 9 patients of thoracic under esophageal cancer (P=0.722,0.307,0.208). The dose target area of V100, V95 and V90 in Plan-3DC were significantly than those in Plan-3D for 19 patients of thoracic middle-lower esophageal cancer (88.62% vs. 95.69%,P=0.000;95.17% vs. 99.79%,P=0.001;97.19% vs. 99.99%,P=0.001). In 4D plan the lung V5, V20 and Dmean of heart were higher than that in 3D plan for all patients (39.49% vs. 37.44%,P=0.016;19.93% vs. 18.87%,P=0.018 and 2607.74 cGy vs. 2389.16 cGy,P=0.004). Conclusions 4DCT positioning technology can accuracy determine individualized expanding boundary by target area of radiotherapy for thoracic middle or lower esophageal cancer. The enlarging target volume increase the dose of radiotherapy for lung, and in the dose range in the 4D plan, but the increased dose of heart should be noted.
Zhang Ying,Wang Yanqiang,Xiao Zhiqing et al. Target volume definition using 4DCT and dosimetric evaluation for esophageal cancer[J]. Chinese Journal of Radiation Oncology, 2014, 23(4): 348-351.
[1] International Commission on Radiation Units and Measurements (ICRU). Prescribing, recording, and reporting photon beam therapy. ICRU report 50[R]. Bethesda:ICRU,1993. [2] International Commission on Radiation Units and Measurements (ICRU). Prescribing, recording, and reporting photon beam therapy (Ssupplement to ICRU report 50).ICRU Report 62[R]. Bethesda:ICRU,1999. [3] Langner UW, Kell PJ. Accuracy in the localization of thoracicand abdominal tumors using respiratory displacement, velocity, and phase[J]. Med Phys,2009,36:386-393. [4] 中国非手术治疗食管癌临床分期专家小组.非手术治疗食管癌的临床分期标准(草案)[J]. 中华放射肿瘤学杂志,2010,19:179-180. [5] Gao XS, Qiao X, Wu F, et al. Pathological analysis of clinical target volume margin for radiotherapy in patients with esophageal and gastroesophagel junction carcinoma[J]. Int J Radiat Oncol Biol Phys,2007,67:389-396. [6] 高献书.食管癌放射治疗指南[A]//高献书,万钧,韩春,等.食管癌放射治疗指南[M]. 北京:中国医药科技出版,2011:17-20. [7] Hashimoto T, Shirato H, Kato M, et al. Real-time monitoring of a digestive tract marker to reduce adverse effects of moving organs at risk (OAR) in radiotherapy for thoracic and abdominal tumors[J]. Int J Radiat Oncol Biol Phys,2005,61:1559-1564. [8] Patel A, Wolfgang JA, Niemierlo A, et al. Implications of respiratory motion as measured by four-dimensional computed tomography for radiation treatment planning of esophageal cancer[J]. Int J Radiat Oncol Biol Phys,2009,74:290-296. [9] Yaremko BP, uerrero TM, cAleer MF, et al. Determination of respiratory motion for distal esophagus cancer using four-dimensional computed tomography[J]. Int J Radiat Oncol Biol Phys,2008,70:145-153. [10] 王玮,李建彬,张英杰,等.基于四维CT的胸中下段食管癌大体肿瘤体积和位移的相关研究[J].中华放射肿瘤学杂志,2012,21:140-143. [11] Preciseandreal Y, Shirato H, Kitamura K, et a1. Precise and real-time measurement of 3D tumor motion in lung due to breathing and heartbeat,measured during radiotherapy[J]. Int J Radiat Oncol Biol Phys,2002,53:822-834.
2014, Vol. 23 
