Wang Xin, Tian Yuan, Tang Yuan, Hu Zhi-Hui, Zhang Jia-Jia, Fu Gui-Shan, Ma Pan, Ren Hua, Zhang Tao, Li Ning, Liu Wen-Yang, Fang Hui, Li Ye-Xiong, Jin Jing
Department of Radiation Oncology, Cancer Hospital and Institute, National Cancer Center, Chinese Academy of Medical Sciences and Peking Union Medical College, Panjiayuan Nanli, Beijing, P. R. China.
Oncotarget. 2017 Jun 13;8(24):39727-39735. doi: 10.18632/oncotarget.14459.
To compare dosimetric parameters of intensity-modulated radiotherapy (IMRT), volumetric-modulated arc therapy (VMAT) and tomotherapy (TOMO) in the adjuvant treatment of gastroesophageal junction (GEJ)/stomach cancer. The planning goal was to maintain high target coverage while keeping the dose to the bowel and bone marrow (BM) as low as possible.
After curative surgery, 16 patients with GEJ/stomach cancer were re-planned by coplanar IMRT (five fixed beam), VMAT (double-arc), and TOMO. The dose to the planning target volume (PTV) was 45 Gy in 25 fractions. The target parameters, including the homogeneity index (HI) and conformity index (CI), and doses to the organs at risk (OARs) were analyzed.
Dosimetric parameters for PTV and OARs were comparable among the three techniques. However, TOMO provided improved conformity (CI = 0.92±0.03) and homogeneity (HI = 1.07±0.02) than IMRT (CI = 0.87±0.03; HI = 1.09±0.02; p < 0.05) and VMAT (CI = 0.86±0.03; HI = 1.09±0.02; p < 0.01). TOMO also improved dose sparing of the bowel (percentage of the volume receiving a dose of ≥ 30 Gy [V30] = 23.24±9.85) and BM (V30 = 71.66±6.15) compared with IMRT (bowel V30 = 30.02±11.74; BM V30 = 83.74±8.42; p < 0.01) and VMAT (bowel V30 = 31.88±11.59; BM V30 = 79.51±9.07; p < 0.01).
TOMO is a good option for adjuvant treatment of GEJ/stomach cancer in patients undergoing radical surgery due to its superior bowel and BM dose sparing, dose conformity and dose homogeneity; however, future studies are required to validate its clinical efficacy.
比较调强放射治疗（IMRT）、容积调强弧形治疗（VMAT）和断层放疗（TOMO）在胃食管交界（GEJ）/胃癌辅助治疗中的剂量学参数。计划目标是在尽可能降低肠道和骨髓（BM）剂量的同时，保持高靶区覆盖率。
16例GEJ/胃癌患者在根治性手术后，通过共面IMRT（五固定野）、VMAT（双弧）和TOMO进行重新计划。计划靶区（PTV）剂量为45 Gy，分25次照射。分析了包括均匀性指数（HI）和适形指数（CI）在内的靶区参数以及危及器官（OARs）的剂量。
三种技术在PTV和OARs的剂量学参数上具有可比性。然而，与IMRT（CI = 0.87±0.03；HI = 1.09±0.02；p < 0.05）和VMAT（CI = 0.86±0.03；HI = 1.09±0.02；p < 0.01）相比，TOMO的适形性（CI = 0.92±0.03）和均匀性（HI = 1.07±0.02）更好。与IMRT（肠道V30 = 30.02±11.74；BM V30 = 83.74±8.42；p < 0.01）和VMAT（肠道V30 = 31.88±11.59；BM V30 = 79.51±9.07；p < 0.01）相比，TOMO在肠道（接受≥30 Gy剂量的体积百分比[V30] = 23.24±9.85）和BM（V30 = 71.66±6.15）的剂量 sparing方面也有所改善。
由于TOMO在肠道和BM剂量 sparing、剂量适形性和剂量均匀性方面具有优势，对于接受根治性手术的GEJ/胃癌患者的辅助治疗是一个不错的选择；然而，需要进一步的研究来验证其临床疗效。
