title: Diagnostic performance of endocytoscopy for evaluating the invasion depth of different morphological types of colorectal tumors.
abstract: OBJECTIVE
  Endocytoscopy (EC) is a next-generation endoscopic technique that enables diagnostic imaging at 450× magnification. In the present study, we retrospectively evaluated the diagnostic performance of EC and magnifying chromoendoscopy (MCE) for diagnosing the invasion depth of colorectal tumors.
  
  
  METHODS
  We investigated 330 lesions with a ≥10-mm tumor diameter that could be diagnosed by both MCE and EC. The lesions were classified according to morphological type as follows: laterally spreading type-granular (LST-G), laterally spreading type-non-granular (LST-NG), protruding, or depressed. After all lesions had been classified by both pit pattern and EC, qualitative and quantitative (invasion depth) diagnoses were made. The diagnostic accuracy was then compared between pit pattern classification and EC classification.
  
  
  RESULTS
  Diagnostic accuracy of EC classification was significantly higher for LST-NG lesions (90.5%) than for protruding lesions (80.6%) (P < 0.05). Diagnostic accuracy for LST-NG lesions was significantly higher with EC classification (90.5%) than with pit pattern classification (79.3%) (P < 0.001). Comparison of the diagnostic performance of EC3a findings using EC classification between LST-NG and protruding lesions revealed a sensitivity of 92.9% versus 11.3% (P < 0.001), positive predictive value of 78.0% versus 27.3% (P < 0.001), negative predictive value of 95.5% versus 56.1% (P < 0.001), and diagnostic accuracy of 87.9% versus 51.2% (P < 0.001), respectively.
  
  
  CONCLUSIONS
  EC is a very useful method for evaluating the invasion depth of LST-NG lesions.
authors.affiliation: Digestive Disease Center, Showa University Northern Yokohama Hospital, Yokohama.
authors.forename: Toyoki
authors.initials: T
authors.lastname: Kudo
authors.affiliation: Digestive Disease Center, Showa University Northern Yokohama Hospital, Yokohama.
authors.forename: Shin-ei
authors.initials: SE
authors.lastname: Kudo
authors.affiliation: Digestive Disease Center, Showa University Northern Yokohama Hospital, Yokohama.
authors.forename: Kunihiko
authors.initials: K
authors.lastname: Wakamura
authors.affiliation: Digestive Disease Center, Showa University Northern Yokohama Hospital, Yokohama.
authors.forename: Yuichi
authors.initials: Y
authors.lastname: Mori
authors.affiliation: Digestive Disease Center, Showa University Northern Yokohama Hospital, Yokohama.
authors.forename: Masashi
authors.initials: M
authors.lastname: Misawa
authors.affiliation: Digestive Disease Center, Showa University Northern Yokohama Hospital, Yokohama.
authors.forename: Takemasa
authors.initials: T
authors.lastname: Hayashi
authors.affiliation: Digestive Disease Center, Showa University Northern Yokohama Hospital, Yokohama.
authors.forename: Makoto
authors.initials: M
authors.lastname: Kutsukawa
authors.affiliation: Digestive Disease Center, Showa University Northern Yokohama Hospital, Yokohama.
authors.forename: Katsuro
authors.initials: K
authors.lastname: Ichimasa
authors.affiliation: Digestive Disease Center, Showa University Northern Yokohama Hospital, Yokohama.
authors.forename: Hideyuki
authors.initials: H
authors.lastname: Miyachi
authors.affiliation: Digestive Disease Center, Showa University Northern Yokohama Hospital, Yokohama.
authors.forename: Fumio
authors.initials: F
authors.lastname: Ishida
authors.affiliation: Digestive Disease Center, Showa University Koto-Toyosu Hospital, Tokyo, Japan.
authors.forename: Haruhiro
authors.initials: H
authors.lastname: Inoue
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003113:Colonoscopy / Q000379:methods*; D015179:Colorectal Neoplasms / Q000145:classification / Q000473:pathology*; D018450:Disease Progression; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007413:Intestinal Mucosa / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D009361:Neoplasm Invasiveness; D009367:Neoplasm Staging / Q000379:methods*; D015203:Reproducibility of Results; D012189:Retrospective Studies
keywords: colorectal cancer; endocytoscopic classification; endocytoscopy; morphological type; pit pattern classification