title: [Anatomic variations in the surgical anatomy of the thoracic esophagus and its surrounding structures].
abstract: BACKGROUND
  Esophagectomy is a challenging procedure due to: a) it is a complex operation; b) it is linked to very high morbidity and mortality rates; c) surgical anatomy of the esophagus is very peculiar. The anatomic variations that can be unexpectedly found during an operation may cause complications and influence the outcome.
  
  
  OBJECTIVE
  To review the anatomic basis for esophagectomy focusing on anatomic variations found in the mediastinal structures based on literature review and cadaver dissection.
  
  
  METHODS
  Literature related to the surgical anatomy of the esophagus and mediastinal structures was reviewed. Also, a total of 20 fresh (non-embalmed, non-preserved, time of death under 12 h) human cadavers were dissected. There were 16 male and mean age was 53 ± 23 years.
  
  
  RESULTS
  Anatomic variations for aorta, azygos system, pleura, vagus nerve, lymph nodes and thoracic duct were documented.
  
  
  CONCLUSIONS
  The organs and structures of the mediastinum may frequently present anatomic variations. Some of these may be clinically significant during an esophagectomy. Because only a part of them may be identified before the operation with the current imaging tools, surgeons must be aware of these anatomic variations.
authors.affiliation: Departamento de Cirurgia, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, SP, Brasil.
authors.forename: Guilherme F
authors.initials: GF
authors.lastname: Takassi
authors.forename: Fernando A M
authors.initials: FA
authors.lastname: Herbella
authors.forename: Marco G
authors.initials: MG
authors.lastname: Patti
mesh_terms: D002102:Cadaver; D004947:Esophagus / Q000033:anatomy & histology* / Q000601:surgery*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged