title: Analysis of dose-volume histogram parameters for radiation pneumonitis after definitive concurrent chemoradiotherapy for esophageal cancer.
abstract: OBJECTIVE
  To evaluate dose-volume histogram (DVH) parameters as predictors of radiation pneumonitis (RP) in esophageal cancer patients treated with definitive concurrent chemoradiotherapy.
  
  
  METHODS
  Thirty-seven esophageal cancer patients treated with radiotherapy with concomitant chemotherapy consisting of 5-fluorouracil and cisplatin were reviewed. Radiotherapy was delivered at 2 Gy per fraction to a total of 60 Gy. For most of the patients, two weeks of interruption was scheduled after 30 Gy. The percentage of lung volume receiving more than 5-50 Gy in increments of 5 Gy (V5-V50, respectively), and the mean lung dose (MLD) were analyzed.
  
  
  RESULTS
  Ten (27%) patients developed RP of grade 2; 2 (5%), grade 3; 0 (0%), grade 4; and 1 (3%), grade 5. By univariate analysis, all DVH parameters (i.e., V5-V50 and MLD) were significantly associated with grade 2 RP (p < 0.01). The incidences of grade 2 RP were 13%, 33%, and 78% in patients with V20s of 24%, 25-36%, and 37%, respectively. The optimal V20 threshold to predict symptomatic RP was 30.5% according to the receiver operating characteristics curve analysis.
  
  
  CONCLUSIONS
  DVH parameters were predictors of symptomatic RP and should be considered in the evaluation of treatment planning for esophageal cancer.
authors.affiliation: Division of Radiation Oncology, Shizuoka Cancer Center Hospital, Nagaizumi, Shizuoka, Japan. h.asakura@scchr.jp
authors.forename: Hirofumi
authors.initials: H
authors.lastname: Asakura
authors.forename: Takayuki
authors.initials: T
authors.lastname: Hashimoto
authors.forename: Sadamoto
authors.initials: S
authors.lastname: Zenda
authors.forename: Hideyuki
authors.initials: H
authors.lastname: Harada
authors.forename: Koichi
authors.initials: K
authors.lastname: Hirakawa
authors.forename: Masashi
authors.initials: M
authors.lastname: Mizumoto
authors.forename: Kazuhisa
authors.initials: K
authors.lastname: Furutani
authors.forename: Shuichi
authors.initials: S
authors.lastname: Hironaka
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Fuji
authors.forename: Shigeyuki
authors.initials: S
authors.lastname: Murayama
authors.forename: Narikazu
authors.initials: N
authors.lastname: Boku
authors.forename: Tetsuo
authors.initials: T
authors.lastname: Nishimura
mesh_terms: D000368:Aged; D003131:Combined Modality Therapy; D004307:Dose-Response Relationship, Radiation; D004938:Esophageal Neoplasms / Q000532:radiotherapy*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D017564:Radiation Pneumonitis / Q000209:etiology*; D020266:Radiotherapy, Conformal / Q000009:adverse effects*