title: Esophageal stenosis associated with tumor regression in radiotherapy for esophageal cancer: frequency and prediction.
abstract: OBJECTIVE
  To determine clinical factors for predicting the frequency and severity of esophageal stenosis associated with tumor regression in radiotherapy for esophageal cancer.
  
  
  METHODS
  The study group consisted of 109 patients with esophageal cancer of T1-4 and Stage I-III who were treated with definitive radiotherapy and achieved a complete response of their primary lesion at Kyushu University Hospital between January 1998 and December 2007. Esophageal stenosis was evaluated using esophagographic images within 3 months after completion of radiotherapy. We investigated the correlation between esophageal stenosis after radiotherapy and each of the clinical factors with regard to tumors and therapy. For validation of the correlative factors for esophageal stenosis, an artificial neural network was used to predict the esophageal stenotic ratio.
  
  
  RESULTS
  Esophageal stenosis tended to be more severe and more frequent in T3-4 cases than in T1-2 cases. Esophageal stenosis in cases with full circumference involvement tended to be more severe and more frequent than that in cases without full circumference involvement. Increases in wall thickness tended to be associated with increases in esophageal stenosis severity and frequency. In the multivariate analysis, T stage, extent of involved circumference, and wall thickness of the tumor region were significantly correlated to esophageal stenosis (p = 0.031, p < 0.0001, and p = 0.0011, respectively). The esophageal stenotic ratio predicted by the artificial neural network, which learned these three factors, was significantly correlated to the actual observed stenotic ratio, with a correlation coefficient of 0.864 (p < 0.001).
  
  
  CONCLUSIONS
  Our study suggested that T stage, extent of involved circumference, and esophageal wall thickness of the tumor region were useful to predict the frequency and severity of esophageal stenosis associated with tumor regression in radiotherapy for esophageal cancer.
authors.affiliation: Department of Clinical Radiology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan.
authors.forename: Kazushige
authors.initials: K
authors.lastname: Atsumi
authors.forename: Yoshiyuki
authors.initials: Y
authors.lastname: Shioyama
authors.forename: Hidetaka
authors.initials: H
authors.lastname: Arimura
authors.forename: Kotaro
authors.initials: K
authors.lastname: Terashima
authors.forename: Takaomi
authors.initials: T
authors.lastname: Matsuki
authors.forename: Saiji
authors.initials: S
authors.lastname: Ohga
authors.forename: Tadamasa
authors.initials: T
authors.lastname: Yoshitake
authors.forename: Takeshi
authors.initials: T
authors.lastname: Nonoshita
authors.forename: Daisuke
authors.initials: D
authors.lastname: Tsurumaru
authors.forename: Kayoko
authors.initials: K
authors.lastname: Ohnishi
authors.forename: Kaori
authors.initials: K
authors.lastname: Asai
authors.forename: Keiji
authors.initials: K
authors.lastname: Matsumoto
authors.forename: Katsumasa
authors.initials: K
authors.lastname: Nakamura
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Honda
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use; D018288:Carcinoma, Small Cell / Q000188:drug therapy / Q000473:pathology / Q000532:radiotherapy*; D002294:Carcinoma, Squamous Cell / Q000188:drug therapy / Q000473:pathology / Q000532:radiotherapy*; D059248:Chemoradiotherapy / Q000379:methods; D004938:Esophageal Neoplasms / Q000188:drug therapy / Q000473:pathology / Q000532:radiotherapy*; D004940:Esophageal Stenosis / Q000453:epidemiology / Q000209:etiology* / Q000473:pathology; D005260:Female; D006801:Humans; D007564:Japan; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D009367:Neoplasm Staging; D016571:Neural Networks, Computer; D012074:Remission Induction / Q000379:methods; D012307:Risk Factors; D012720:Severity of Illness Index; D047368:Tumor Burden