title: Advantages of magnifying narrow-band imaging for diagnosing colorectal cancer coexisting with sessile serrated adenoma/polyp.
abstract: OBJECTIVE
  In the present study, we investigated the advantages of narrow-band imaging (NBI) for efficient diagnosis of sessile serrated adenoma/polyp (SSA/P). The main objective of this study was to analyze the characteristic features of cancer coexisting with serrated lesion by carrying out NBI.
  
  
  METHODS
  We evaluated 264 non-malignant serrated lesions by using three modalities (conventional white light colonoscopy, magnifying chromoendoscopy, and magnifying NBI). Of the evaluated cancer cases with serrated lesions, 37 fulfilled the inclusion criteria.
  
  
  RESULTS
  In diagnosing non-malignant SSA/P, an expanded crypt opening (ECO) under magnifying NBI is a useful sign. One hundred and twenty-five lesions (87%) of observed ECO were, at the same time, detected to have type II open pit pattern, which is known to be a valuable indicator when using magnifying chromoendoscopy. ECO had high sensitivity of 80% for identifying SSA/P, with 62% specificity and 83% positive predictive value (PPV). In detecting the cancer with SSA/P, irregular vessels under magnifying NBI were frequently observed with 100% sensitivity and 99% specificity, 86% PPV and 100% negative predictive value.
  
  
  CONCLUSIONS
  A focus on irregular vessels in serrated lesions might be useful for identification of cancer with SSA/P. This is an advantage of carrying out magnifying NBI in addition to being used simultaneously with other modalities by switching, and observations can be made by using wash-in water alone. We can carry out advanced examinations for selected lesions with irregular vessels. To confirm cancerous demarcation and invasion depth, a combination of all three aforementioned modalities should be done.
authors: Division of Gastroenterology, Cancer Institute Hospital of Japanese Foundation for Cancer Research, Tokyo, Japan.
authors: Akiko
authors: A
authors: Chino
authors: Division of Gastroenterology, Cancer Institute Hospital of Japanese Foundation for Cancer Research, Tokyo, Japan.
authors: Hiroki
authors: H
authors: Osumi
authors: Division of Gastroenterology, Cancer Institute Hospital of Japanese Foundation for Cancer Research, Tokyo, Japan.
authors: Teruhito
authors: T
authors: Kishihara
authors: Division of Gastroenterology, Cancer Institute Hospital of Japanese Foundation for Cancer Research, Tokyo, Japan.
authors: Kenjiro
authors: K
authors: Morishige
authors: Division of Gastroenterology, Cancer Institute Hospital of Japanese Foundation for Cancer Research, Tokyo, Japan.
authors: Hirotaka
authors: H
authors: Ishikawa
authors: Division of Gastroenterology, Cancer Institute Hospital of Japanese Foundation for Cancer Research, Tokyo, Japan.
authors: Yoshiro
authors: Y
authors: Tamegai
authors: Division of Gastroenterology, Cancer Institute Hospital of Japanese Foundation for Cancer Research, Tokyo, Japan.
authors: Masahiro
authors: M
authors: Igarashi
mesh_terms: D000236:Adenoma / Q000150:complications / Q000175:diagnosis*; D003111:Colonic Polyps / Q000150:complications / Q000175:diagnosis*; D003113:Colonoscopy / Q000379:methods*; D015179:Colorectal Neoplasms / Q000150:complications / Q000175:diagnosis*; D003937:Diagnosis, Differential; D006801:Humans; D007089:Image Enhancement; D062048:Narrow Band Imaging / Q000379:methods; D015203:Reproducibility of Results; D012189:Retrospective Studies
keywords: cancer with serrated polyp; cancer with sessile serrated adenoma/polyp; endoscopic diagnosis; irregular vessel pattern; narrow-band imaging