title: Endoscopic features of early-stage signet-ring-cell carcinoma of the stomach.
abstract: OBJECTIVE
  To identify the features of early signet ring cell gastric carcinoma using magnification endoscopy with narrow band imaging (NBI).
  
  
  METHODS
  A retrospective review was conducted of 12 cases of early signet ring cell gastric carcinoma who underwent treatment in a single institution between January 2009 and April 2013. All patients had magnification endoscopy with NBI and indigo carmine contrast to closely examine the mucosal architecture, including the microvasculature and arrangement of gastric pits. Histologic examination of the final endoscopic submucosal dissection or gastrectomy specimen was performed and compared with the endoscopic findings to identify patterns specific to signet ring cell carcinoma.
  
  
  RESULTS
  Twelve patients with early signet ring cell gastric carcinoma were identified; 75% were male, and average age was 61 years. Most of the lesions were stage T1a (83%), while the remainder were T1b (17%). The mean lesion size was 1.4 cm(2). On standard endoscopy, all 12 patients had a pale, flat lesion without any evidence of mucosal abnormality such as ulceration, elevation, or depression. On magnification endoscopy with NBI, all of the patients had irregularities in the glands and microvasculature consistent with early gastric cancer. In addition, all 12 patients exhibited the "stretch sign", an elongation or expansion of the architectural structure. Histologic examination of the resected specimens demonstrated an expanded and edematous mucosal layer infiltrated with tumor cells.
  
  
  CONCLUSIONS
  The "stretch sign" appears to be specific for signet ring cell carcinoma and may aid in the early diagnosis and treatment of this aggressive pathology.
authors.affiliation: Chainarong Phalanusitthepha, Kevin L Grimes, Haruo Ikeda, Hiroki Sato, Chiaki Sato, Haruhiro Inoue, Digestive Disease Center, Showa University Koto-Toyosu Hospital, Tokyo 135-8577, Japan.
authors.forename: Chainarong
authors.initials: C
authors.lastname: Phalanusitthepha
authors.affiliation: Chainarong Phalanusitthepha, Kevin L Grimes, Haruo Ikeda, Hiroki Sato, Chiaki Sato, Haruhiro Inoue, Digestive Disease Center, Showa University Koto-Toyosu Hospital, Tokyo 135-8577, Japan.
authors.forename: Kevin L
authors.initials: KL
authors.lastname: Grimes
authors.affiliation: Chainarong Phalanusitthepha, Kevin L Grimes, Haruo Ikeda, Hiroki Sato, Chiaki Sato, Haruhiro Inoue, Digestive Disease Center, Showa University Koto-Toyosu Hospital, Tokyo 135-8577, Japan.
authors.forename: Haruo
authors.initials: H
authors.lastname: Ikeda
authors.affiliation: Chainarong Phalanusitthepha, Kevin L Grimes, Haruo Ikeda, Hiroki Sato, Chiaki Sato, Haruhiro Inoue, Digestive Disease Center, Showa University Koto-Toyosu Hospital, Tokyo 135-8577, Japan.
authors.forename: Hiroki
authors.initials: H
authors.lastname: Sato
authors.affiliation: Chainarong Phalanusitthepha, Kevin L Grimes, Haruo Ikeda, Hiroki Sato, Chiaki Sato, Haruhiro Inoue, Digestive Disease Center, Showa University Koto-Toyosu Hospital, Tokyo 135-8577, Japan.
authors.forename: Chiaki
authors.initials: C
authors.lastname: Sato
authors.affiliation: Chainarong Phalanusitthepha, Kevin L Grimes, Haruo Ikeda, Hiroki Sato, Chiaki Sato, Haruhiro Inoue, Digestive Disease Center, Showa University Koto-Toyosu Hospital, Tokyo 135-8577, Japan.
authors.forename: Chananya
authors.initials: C
authors.lastname: Hokierti
authors.affiliation: Chainarong Phalanusitthepha, Kevin L Grimes, Haruo Ikeda, Hiroki Sato, Chiaki Sato, Haruhiro Inoue, Digestive Disease Center, Showa University Koto-Toyosu Hospital, Tokyo 135-8577, Japan.
authors.forename: Haruhiro
authors.initials: H
authors.lastname: Inoue
keywords: Early gastric cancer; Endoscopic submucosal dissection; Magnification endoscopy; Narrow band imaging; Signet ring cells; Stretch sign