title: Positive esophageal proximal resection margin: an important prognostic factor for esophageal cancer that warrants adjuvant therapy.
abstract: BACKGROUND
  Positive esophageal proximal resection margin (ERM+) following esophagectomy was considered as incomplete or R1 resection. The clinicopathological data and long-term prognosis of esophageal cancer (EC) patients with ERM+ after esophagectomy were still unknown. Therefore, the aim of this study was to assess the clinical significance of ERM+ and its therapeutic option.
  
  
  METHODS
  From November 2008 to December 2014, 3,594 patients with histologically confirmed EC underwent radical resection in our department. Among them there were 37 patients (1.03%) who had ERM+. ERM+ was defined as carcinoma or atypical hyperplasia (severe or moderate) at the residual esophageal margin in our study. For comparison, another 74 patients with negative esophageal proximal resection margin (ERM-) were propensity-matched at a ratio of 1:2 as control group according to sex, age, tumor location and TNM staging. The relevant prognostic factors were investigated by univariate and multivariate regression analysis.
  
  
  RESULTS
  In this large cohort of patients, the rate of ERM+ was 1.03%. The median survival time was 35.000 months in patients with ERM+, significantly worse than 68.000 months in those with ERM- (Chi-square =4.064, P=0.044). Survival in patients with esophageal residual atypical hyperplasia (severe or moderate) was similar to those with esophageal residual carcinoma. Survival rate in stage I-II was higher than that in stage III-IV (Chi-square =27.598, P=0.000) in ERM-; But there was no difference between the two subgroups of patients in ERM+. Furthermore, in those patients with ERM+, survival was better in those who having adjuvant therapy, compared to those without adjuvant therapy (Chi-square =5.480, P=0.019). And the average survival time which was improved to a well situation for ERM+ patients who have adjuvant therapy was 68.556 months which is comparable to average survival time (65.815 months) of ERM- for those patients who are at earlier stages.
  
  
  CONCLUSIONS
  ERM+ after esophagectomy nowadays is of low incidence but still an important prognostic factor for patients with EC. Survival of ERM+ patients who have adjuvant therapy was improved to a well situation which is comparable to overall survival (OS) rate of ERM- for those patients who are at earlier stages.
authors.affiliation: Department of Thoracic Surgery, West China Hospital of Sichuan University, Chengdu 610041, China;; Department of Thoracic Surgery, The First Hospital of Hebei Medical University, Shijiazhuang 050031, China.
authors.forename: Yun-Cang
authors.initials: YC
authors.lastname: Wang
authors.affiliation: Department of Thoracic Surgery, West China Hospital of Sichuan University, Chengdu 610041, China.
authors.forename: Han-Yu
authors.initials: HY
authors.lastname: Deng
authors.affiliation: Department of Thoracic Surgery, West China Hospital of Sichuan University, Chengdu 610041, China.
authors.forename: Wen-Ping
authors.initials: WP
authors.lastname: Wang
authors.affiliation: Department of Pathology, West China Hospital of Sichuan University, Chengdu 610041, China.
authors.forename: Du
authors.initials: D
authors.lastname: He
authors.affiliation: Department of Thoracic Surgery, West China Hospital of Sichuan University, Chengdu 610041, China.
authors.forename: Peng-Zhi
authors.initials: PZ
authors.lastname: Ni
authors.affiliation: Department of Thoracic Surgery, West China Hospital of Sichuan University, Chengdu 610041, China.
authors.forename: Wei-Peng
authors.initials: WP
authors.lastname: Hu
authors.affiliation: Department of Thoracic Surgery, West China Hospital of Sichuan University, Chengdu 610041, China.
authors.forename: Zhi-Qiang
authors.initials: ZQ
authors.lastname: Wang
authors.affiliation: Department of Thoracic Surgery, West China Hospital of Sichuan University, Chengdu 610041, China.
authors.forename: Long-Qi
authors.initials: LQ
authors.lastname: Chen
keywords: Esophageal carcinoma (EC); positive resection margin; prognosis; therapy