title: Impact of clinical experience on type V pit pattern analysis using magnifying chromoendoscopy in early colorectal cancer: a cross-sectional interpretation test.
abstract: BACKGROUND
  Although type V pit pattern analysis is effective in determining the invasion depth of early colorectal cancers, the clinical results may vary because findings are operator-dependent. This study aimed to assess the benefits of type V pit pattern analysis in estimating the invasion depth using magnifying chromoendoscopy compared to that with conventional colonoscopy.
  
  
  METHODS
  A cross-sectional interpretation test involving 32 endoscopists with varying levels of experience performing colonoscopies was conducted. Fifty histopathologically diagnosed cases of intramucosal or submucosal cancer were selected retrospectively. The lesions were classified as superficial or deep by the endoscopists, based on magnifying chromoendoscopic and non-magnifying endoscopic images. The endoscopists were classified into 3 groups based on the number of colonoscopies performed: I (<500), II (501-5000), and III (>5000). Differences in the interpretation of invasion depth between group III and groups I and II were assessed using the Mann-Whitney U test.
  
  
  RESULTS
  There was no significant difference in the median number of correct interpretations using non-magnifying endoscopic images among the groups. However, a significant difference (P = 0.007) was observed between the results of groups III and I when the analysis was performed using magnifying chromoendoscopic images.
  
  
  CONCLUSIONS
  When performed by less experienced endoscopists, pit pattern analysis of colonic lesions using magnifying chromoendoscopy is not a reliable modality for estimating invasion depth in early colorectal cancer.
authors.affiliation: Endoscopy Division, National Cancer Center Hospital, 5-1-1 Tsukiji Chuo-ku, Tokyo 104-0045, Japan. tasakamo@ncc.go.jp.
authors.forename: Taku
authors.initials: T
authors.lastname: Sakamoto
authors.forename: Takahisa
authors.initials: T
authors.lastname: Matsuda
authors.forename: Takeshi
authors.initials: T
authors.lastname: Nakajima
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Saito
authors.forename: Takahiro
authors.initials: T
authors.lastname: Fujii
mesh_terms: D000230:Adenocarcinoma / Q000473:pathology*; D003113:Colonoscopy / Q000592:standards*; D015179:Colorectal Neoplasms / Q000473:pathology*; D004396:Coloring Agents; D003430:Cross-Sectional Studies; D006801:Humans; D009361:Neoplasm Invasiveness; D015588:Observer Variation; D012189:Retrospective Studies
chemical_list: D004396:Coloring Agents