title: The prognostic value of metastatic lymph node number and ratio in oesophageal squamous cell carcinoma patients with or without neoadjuvant chemoradiation.
abstract: OBJECTIVE
  We aim to evaluate the prognostic value of metastatic lymph node number (MLN) and ratio (MLR) in oesophageal squamous cell carcinoma (OSCC) patients with or without neoadjuvant chemoradiation.
  
  
  METHODS
  Two thousand one hundred and fifty-one OSCC patients receiving oesophagectomy with (n = 850) or without (n = 1301) neoadjuvant chemoradiation were included. The MLN was categorized into 0 (N0), 1-2 (N1), 3-6 (N2) and more than 7 (N3); the MLR was categorized into 0, 0-0.2 and >0.2. The prognostic value was evaluated with survival analysis using the Cox proportional hazards regression model and the Kaplan-Meier method.
  
  
  RESULTS
  In patients without neoadjuvant chemoradiation, the 3-year overall survival rates were 54.8, 34.4, 21.8 and 6.5% with MLN = 0, 1-2, 3-6 and more than 7, respectively (P < 0.001). The 3-year overall survival rates were 54.7, 31.2 and 14.2% with MLR = 0, 0-0.2 and more than 0.2, respectively (P < 0.001). In patients with neoadjuvant chemoradiation, the 3-year overall survival rates were 49.0, 28.4, 12.5 and 0.0% with MLN = 0, 1-2, 3-6 and more than 7, respectively (P < 0.001). However, the survival curves of MLN = 3-6 and MLN ≥7 overlapped on the Kaplan-Meier plots. In contrast, MLR demonstrated good ability to show the survival differences on the Kaplan-Meier plots. The 3-year overall survival rates were 48.9, 27.3 and 0.0% with MLR = 0, 0-0.2 and more than 0.2, respectively (P < 0.001).
  
  
  CONCLUSIONS
  Both MLN and MLR were significant prognostic factors in OSCC patients regardless of neoadjuvant chemoradiation. But in patients with neoadjuvant chemoradiation, the survival rates were similar between ypN2 and ypN3 patients, suggesting that there was no necessity of separating patients into ypN2 and ypN3 stages.
authors.affiliation: Division of Chest Surgery, Department of Surgery, Taipei Veterans General Hospital, Taipei, Taiwan School of Medicine, National Yang-Ming University, Taipei, Taiwan.
authors.forename: Hung-Che
authors.initials: HC
authors.lastname: Chien
authors.affiliation: Institute of Health and Welfare Policy, National Yang-Ming University, Taipei, Taiwan.
authors.forename: Hui-Shan
authors.initials: HS
authors.lastname: Chen
authors.affiliation: Institute of Health and Welfare Policy, National Yang-Ming University, Taipei, Taiwan.
authors.forename: Shiao-Chi
authors.initials: SC
authors.lastname: Wu
authors.affiliation: Division of Chest Surgery, Department of Surgery, Taipei Veterans General Hospital, Taipei, Taiwan School of Medicine, National Yang-Ming University, Taipei, Taiwan hsupokuei@yahoo.com.tw.
authors.forename: Po-Kuei
authors.initials: PK
authors.lastname: Hsu
authors.affiliation: Division of Thoracic Surgery, Department of Surgery, Far Eastern Memorial Hospital, New Taipei City, Taiwan.
authors.forename: Chao-Yu
authors.initials: CY
authors.lastname: Liu
authors.affiliation: Division of Thoracic Surgery, Department of Surgery, Changhua Christian Hospital, Taichung, Taiwan.
authors.forename: Bing-Yen
authors.initials: BY
authors.lastname: Wang
authors.affiliation: Division of Thoracic Surgery, Department of Surgery, Koo Foundation Sun Yat-Sen Cancer Center, Taipei, Taiwan.
authors.forename: Chih-Hsun
authors.initials: CH
authors.lastname: Shih
authors.affiliation: Division of Thoracic Surgery, Department of Surgery, Koo Foundation Sun Yat-Sen Cancer Center, Taipei, Taiwan.
authors.forename: Chia-Chuan
authors.initials: CC
authors.lastname: Liu
mesh_terms: D002294:Carcinoma, Squamous Cell / Q000401:mortality / Q000556:secondary* / Q000628:therapy; D004938:Esophageal Neoplasms / Q000401:mortality / Q000556:secondary* / Q000628:therapy; D000077277:Esophageal Squamous Cell Carcinoma; D016629:Esophagectomy; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008197:Lymph Node Excision; D008198:Lymph Nodes / Q000473:pathology*; D008207:Lymphatic Metastasis; D008297:Male; D008875:Middle Aged; D020360:Neoadjuvant Therapy; D009367:Neoplasm Staging; D011379:Prognosis; D012189:Retrospective Studies; D015996:Survival Rate / Q000639:trends; D013624:Taiwan / Q000453:epidemiology; D013997:Time Factors
keywords: Lymph node; Oesophageal cancer; Prognosis