title: Recurrence risk model for esophageal cancer after radical surgery.
abstract: OBJECTIVE
  The aim of the present study was to construct a risk assessment model which was tested by disease-free survival (DFS) of esophageal cancer after radical surgery.
  
  
  METHODS
  A total of 164 consecutive esophageal cancer patients who had undergone radical surgery between January 2005 and December 2006 were retrospectively analyzed. The cutpoint of value at risk (VaR) was inferred by stem-and-leaf plot, as well as by independent-samples t-test for recurrence-free time, further confirmed by crosstab chi-square test, univariate analysis and Cox regression analysis for DFS.
  
  
  RESULTS
  The cutpoint of VaR was 0.3 on the basis of our model. The rate of recurrence was 30.3% (30/99) and 52.3% (34/65) in VaR <0.3 and VaR ≥0.3 (chi-square test, (χ) (2) =7.984, P=0.005), respectively. The 1-, 3-, and 5-year DFS of esophageal cancer after radical surgery was 70.4%, 48.7%, and 45.3%, respectively in VaR ≥0.3, whereas 91.5%, 75.8%, and 67.3%, respectively in VaR <0.3 (Log-rank test, (χ) (2) =9.59, P=0.0020), and further confirmed by Cox regression analysis [hazard ratio =2.10, 95% confidence interval (CI): 1.2649-3.4751; P=0.0041].
  
  
  CONCLUSIONS
  The model could be applied for integrated assessment of recurrence risk after radical surgery for esophageal cancer.
authors.affiliation: Department of Radiotherapy, Jiangsu Cancer Hospital, Nanjing 210009, China.
authors.forename: Jincheng
authors.initials: J
authors.lastname: Lu
authors.forename: Hua
authors.initials: H
authors.lastname: Tao
authors.forename: Dan
authors.initials: D
authors.lastname: Song
authors.forename: Cheng
authors.initials: C
authors.lastname: Chen
keywords: Esophageal cancer; model; radical surgery; recurrence