title: Tomotherapy as an adjuvant treatment for gastroesophageal junction and stomach cancer may reduce bowel and bone marrow toxicity compared to intensity-modulated radiotherapy and volumetric-modulated arc therapy.
abstract: OBJECTIVE
  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.
  
  
  METHODS
  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.
  
  
  RESULTS
  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).
  
  
  CONCLUSIONS
  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.
authors.affiliation: 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.
authors.forename: Xin
authors.initials: X
authors.lastname: Wang
authors.affiliation: 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.
authors.forename: Yuan
authors.initials: Y
authors.lastname: Tian
authors.affiliation: 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.
authors.forename: Yuan
authors.initials: Y
authors.lastname: Tang
authors.affiliation: 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.
authors.forename: Zhi-Hui
authors.initials: ZH
authors.lastname: Hu
authors.affiliation: 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.
authors.forename: Jia-Jia
authors.initials: JJ
authors.lastname: Zhang
authors.affiliation: 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.
authors.forename: Gui-Shan
authors.initials: GS
authors.lastname: Fu
authors.affiliation: 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.
authors.forename: Pan
authors.initials: P
authors.lastname: Ma
authors.affiliation: 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.
authors.forename: Hua
authors.initials: H
authors.lastname: Ren
authors.affiliation: 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.
authors.forename: Tao
authors.initials: T
authors.lastname: Zhang
authors.affiliation: 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.
authors.forename: Ning
authors.initials: N
authors.lastname: Li
authors.affiliation: 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.
authors.forename: Wen-Yang
authors.initials: WY
authors.lastname: Liu
authors.affiliation: 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.
authors.forename: Hui
authors.initials: H
authors.lastname: Fang
authors.affiliation: 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.
authors.forename: Ye-Xiong
authors.initials: YX
authors.lastname: Li
authors.affiliation: 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.
authors.forename: Jing
authors.initials: J
authors.lastname: Jin
mesh_terms: D000328:Adult; D000368:Aged; D001855:Bone Marrow Diseases / Q000209:etiology / Q000517:prevention & control*; D017322:Clinical Trials, Phase II as Topic; D004938:Esophageal Neoplasms / Q000473:pathology / Q000532:radiotherapy*; D004943:Esophagogastric Junction / Q000473:pathology / Q000528:radiation effects*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D015212:Inflammatory Bowel Diseases / Q000209:etiology / Q000517:prevention & control*; D008297:Male; D008875:Middle Aged; D058958:Organs at Risk / Q000528:radiation effects; D011379:Prognosis; D011446:Prospective Studies; D011880:Radiotherapy Planning, Computer-Assisted / Q000379:methods; D018714:Radiotherapy, Adjuvant / Q000009:adverse effects*; D050397:Radiotherapy, Intensity-Modulated / Q000379:methods*; D013274:Stomach Neoplasms / Q000473:pathology / Q000532:radiotherapy*
keywords: gastric cancer; gastroesophageal junction cancer; helical tomotherapy; intensity-modulated radiotherapy; volumetric-modulated arc therapy