title: Three-field vs two-field lymph node dissection for esophageal cancer: a meta-analysis.
abstract: OBJECTIVE
  To assess the effects of 3-field lymphadenectomy for esophageal carcinoma.
  
  
  METHODS
  We conducted a computerized literature search of the PubMed, Cochrane Controlled Trials Register, and EMBASE databases from their inception to present. Randomized controlled trials (RCTs) or observational epidemiological studies (cohort studies) that compared the survival rates and/or postoperative complications between 2-field lymphadenectomy (2FL) and 3-field lymphadenectomy (3FL) for esophageal carcinoma with R0 resection were included. Meta-analysis was conducted using published data on 3FL vs 2FL in esophageal carcinoma patients. End points were 1-, 3-, and 5-year overall survival rates and postoperative complications, including recurrent nerve palsy, anastomosis leak, pulmonary complications, and chylothorax. Subgroup analysis was performed on the involvement of recurrent laryngeal lymph nodes.
  
  
  RESULTS
  Two RCTs and 18 observational studies with over 7000 patients were included. There was a clear benefit for 3FL in the 1- (RR = 1.16; 95%CI: 1.09-1.24; P < 0.01), 3- (RR = 1.44; 95%CI: 1.19-1.75; P < 0.01), and 5-year overall survival rates (RR = 1.37; 95%CI: 1.18-1.59; P < 0.01). For postoperative complications, 3FL was associated with significantly more recurrent nerve palsy (RR = 1.43; 95%CI: 1.28-1.60; P = 0.02) and anastomosis leak (RR = 1.26; 95%CI: 1.05-1.52; P = 0.09). In contrast, there was no significant difference for pulmonary complications (RR = 0.93; 95%CI: 0.75-1.16, random-effects model; P = 0.27) or chylothorax (RR = 0.77; 95%CI: 0.32-1.85; P = 0.69).
  
  
  CONCLUSIONS
  This meta-analysis shows that 3FL improves overall survival rate but has more complications. Because of the high heterogeneity among outcomes, definite conclusions are difficult to draw.
authors.affiliation: Guo-Wei Ma, Dong-Rong Situ, Qi-Long Ma, Hao Long, Lan-Jun Zhang, Peng Lin, Tie-Hua Rong, Department of Thoracic Surgery, Sun Yat-sen University Cancer Center; State Key Laboratory of Oncology in South China, Guangzhou 510060, Guangdong Province, China.
authors.forename: Guo-Wei
authors.initials: GW
authors.lastname: Ma
authors.affiliation: Guo-Wei Ma, Dong-Rong Situ, Qi-Long Ma, Hao Long, Lan-Jun Zhang, Peng Lin, Tie-Hua Rong, Department of Thoracic Surgery, Sun Yat-sen University Cancer Center; State Key Laboratory of Oncology in South China, Guangzhou 510060, Guangdong Province, China.
authors.forename: Dong-Rong
authors.initials: DR
authors.lastname: Situ
authors.affiliation: Guo-Wei Ma, Dong-Rong Situ, Qi-Long Ma, Hao Long, Lan-Jun Zhang, Peng Lin, Tie-Hua Rong, Department of Thoracic Surgery, Sun Yat-sen University Cancer Center; State Key Laboratory of Oncology in South China, Guangzhou 510060, Guangdong Province, China.
authors.forename: Qi-Long
authors.initials: QL
authors.lastname: Ma
authors.affiliation: Guo-Wei Ma, Dong-Rong Situ, Qi-Long Ma, Hao Long, Lan-Jun Zhang, Peng Lin, Tie-Hua Rong, Department of Thoracic Surgery, Sun Yat-sen University Cancer Center; State Key Laboratory of Oncology in South China, Guangzhou 510060, Guangdong Province, China.
authors.forename: Hao
authors.initials: H
authors.lastname: Long
authors.affiliation: Guo-Wei Ma, Dong-Rong Situ, Qi-Long Ma, Hao Long, Lan-Jun Zhang, Peng Lin, Tie-Hua Rong, Department of Thoracic Surgery, Sun Yat-sen University Cancer Center; State Key Laboratory of Oncology in South China, Guangzhou 510060, Guangdong Province, China.
authors.forename: Lan-Jun
authors.initials: LJ
authors.lastname: Zhang
authors.affiliation: Guo-Wei Ma, Dong-Rong Situ, Qi-Long Ma, Hao Long, Lan-Jun Zhang, Peng Lin, Tie-Hua Rong, Department of Thoracic Surgery, Sun Yat-sen University Cancer Center; State Key Laboratory of Oncology in South China, Guangzhou 510060, Guangdong Province, China.
authors.forename: Peng
authors.initials: P
authors.lastname: Lin
authors.affiliation: Guo-Wei Ma, Dong-Rong Situ, Qi-Long Ma, Hao Long, Lan-Jun Zhang, Peng Lin, Tie-Hua Rong, Department of Thoracic Surgery, Sun Yat-sen University Cancer Center; State Key Laboratory of Oncology in South China, Guangzhou 510060, Guangdong Province, China.
authors.forename: Tie-Hua
authors.initials: TH
authors.lastname: Rong
mesh_terms: D002277:Carcinoma / Q000401:mortality / Q000556:secondary / Q000601:surgery*; D016009:Chi-Square Distribution; D004938:Esophageal Neoplasms / Q000401:mortality / Q000473:pathology / Q000601:surgery*; D016629:Esophagectomy; D006801:Humans; D008197:Lymph Node Excision / Q000009:adverse effects / Q000379:methods* / Q000401:mortality; D008207:Lymphatic Metastasis; D016017:Odds Ratio; D011183:Postoperative Complications / Q000401:mortality; D012307:Risk Factors; D016019:Survival Analysis; D015996:Survival Rate; D013997:Time Factors; D016896:Treatment Outcome
keywords: Cancer; Complication; Lymph node dissection; Oesophagus; Survival