title: Nodal skip metastasis is not a predictor of survival in thoracic esophageal squamous cell carcinoma.
abstract: BACKGROUND
  The presence of nodal skip metastasis (NSM) has been found to be of clinical importance in non-small cell lung cancer, but the study of this phenomenon in esophageal carcinoma is relatively rare. The purpose of this study was to identify risk factors influencing NSM and to assess its prognostic value in thoracic esophageal squamous cell carcinoma (ESCC).
  
  
  METHODS
  A total of 207 patients with thoracic ESCC who underwent three-field lymphadenectomy and who had lymph node metastasis were reviewed. Associations of NSM occurrence with the clinicopathological characteristics of patients and primary tumors were evaluated using logistic regression analysis. The influence of NSM on the overall survival (OS) was assessed by log-rank tests and Cox regression analysis.
  
  
  RESULTS
  NSM were present in 58 (26%) patients. No factor was significantly associated with the incidence of NSM except for the location of primary tumor. There were no NSMs in the 29 patients from our study with upper thoracic ESCC, and the rates of tumors occurrence in the middle and lower third of the esophagus were 38.9 and 14.9%, respectively. The median OS was 30 months, and no significant difference in OS was found between the patients with or without NSM (p=0.767). Only N status was found to be the independent risk factor for OS by Cox multivariate analysis.
  
  
  CONCLUSIONS
  NSM is common in thoracic ESCC, especially in patients with tumors located in the middle and lower third of the esophagus. However, the presence of NSM did not predict prognosis.
authors.affiliation: Department of Radiation Oncology, Fudan University Shanghai Cancer Center, Shanghai, China.
authors.forename: Zhengfei
authors.initials: Z
authors.lastname: Zhu
authors.forename: Weiwei
authors.initials: W
authors.lastname: Yu
authors.forename: Hecheng
authors.initials: H
authors.lastname: Li
authors.forename: Kuaile
authors.initials: K
authors.lastname: Zhao
authors.forename: Weixin
authors.initials: W
authors.lastname: Zhao
authors.forename: Yawei
authors.initials: Y
authors.lastname: Zhang
authors.forename: Menghong
authors.initials: M
authors.lastname: Sun
authors.forename: Qiao
authors.initials: Q
authors.lastname: Wei
authors.forename: Haiquan
authors.initials: H
authors.lastname: Chen
authors.forename: Jiaqing
authors.initials: J
authors.lastname: Xiang
authors.forename: Xiaolong
authors.initials: X
authors.lastname: Fu
mesh_terms: D000328:Adult; D000368:Aged; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use; D002294:Carcinoma, Squamous Cell / Q000401:mortality* / Q000556:secondary / Q000628:therapy; D017024:Chemotherapy, Adjuvant; D003131:Combined Modality Therapy; D004938:Esophageal Neoplasms / Q000401:mortality* / Q000473:pathology / Q000628:therapy; D016629:Esophagectomy / Q000401:mortality*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008197:Lymph Node Excision / Q000401:mortality*; D008207:Lymphatic Metastasis; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000401:mortality* / Q000473:pathology / Q000628:therapy; D009367:Neoplasm Staging; D011379:Prognosis; D018714:Radiotherapy, Adjuvant; D012307:Risk Factors; D015996:Survival Rate; D013899:Thoracic Neoplasms / Q000401:mortality* / Q000556:secondary / Q000628:therapy