title: Squamous cell carcinoma in an esophageal diverticulum below the aortic arch.
abstract: BACKGROUND
  Esophageal diverticula frequently arise from pharyngoesophageal transition area, tracheal bifurcation and epiphrenic region. Carcinoma arising from esophageal diverticulum is rarely seen. We report a patient with a squamous cell carcinoma arising within an esophageal diverticulum below the aortic arch.
  
  
  METHODS
  A 70-year-old man was diagnosed to have a squamous cell carcinoma of the vocal cord with enlarged lymph nodes in the neck, as well as a squamous cell carcinoma arising within an esophageal diverticulum below the aortic arch. There have been no reported cases of esophageal cancer arising from a diverticulum below the aortic arch. Preoperative radiotherapy for the esophageal cancer and pharyngeal cancer was given, followed by surgery. The excised specimen of the esophageal diverticulum and its external appearance revealed that it lacked muscle fibers, with a type 0-IIa lesion arising from the diverticulum. Microscopic examination showed three lymph nodes at the superior mediastinum were positive for malignancy. Bilateral pleural dissemination was detected 7 months after esophagectomy.
  
  
  CONCLUSIONS
  Cancer arising from an esophageal diverticulum is mainly found at an advanced stage because of delayed diagnosis. The absence of muscularis propia may lead to early invasion. Thus, cancers within an esophageal diverticulum are considered to be at a more advanced stage than similar cancers arising elsewhere.
  
  
  CONCLUSIONS
  For detecting of cancer arising from an esophageal diverticulum, a high index of awareness is important. Delay in diagnosis makes surgical management difficult.
authors.affiliation: Department of Surgery, Akita University Graduate School of Medicine, 1-1-1 Hondo, Akita 010-8543, Japan.
authors.forename: Akiyuki
authors.initials: A
authors.lastname: Wakita
authors.forename: Satoru
authors.initials: S
authors.lastname: Motoyama
authors.forename: Yusuke
authors.initials: Y
authors.lastname: Sato
authors.forename: Kei
authors.initials: K
authors.lastname: Yoshino
authors.forename: Tomohiko
authors.initials: T
authors.lastname: Sasaki
authors.forename: Hajime
authors.initials: H
authors.lastname: Saito
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Minamiya
authors.forename: Jun-Ichi
authors.initials: J
authors.lastname: Ogawa