title: Pathological diagnostic criterion of blood and lymphatic vessel invasion in colorectal cancer: a framework for developing an objective pathological diagnostic system using the Delphi method, from the Pathology Working Group of the Japanese Society for Cancer of the Colon and Rectum.
abstract: OBJECTIVE
  The goal of this study is to create an objective pathological diagnostic system for blood and lymphatic vessel invasion (BLI).
  
  
  METHODS
  1450 surgically resected colorectal cancer specimens from eight hospitals were reviewed. Our first step was to compare the current practice of pathology assessment among eight hospitals. Then, H&E stained slides with or without histochemical/immunohistochemical staining were assessed by eight pathologists and concordance of BLI diagnosis was checked. In addition, histological findings associated with BLI having good concordance were reviewed. Based on these results, framework for developing diagnostic criterion was developed, using the Delphi method. The new criterion was evaluated using 40 colorectal cancer specimens.
  
  
  RESULTS
  Frequency of BLI diagnoses, number of blocks obtained and stained for assessment of BLI varied among eight hospitals. Concordance was low for BLI diagnosis and was not any better when histochemical/immunohistochemical staining was provided. All histological findings associated with BLI from H&E staining were poor in agreement. However, observation of elastica-stained internal elastic membrane covering more than half of the circumference surrounding the tumour cluster as well as the presence of D2-40-stained endothelial cells covering more than half of the circumference surrounding the tumour cluster showed high concordance. Based on this observation, we developed a framework for pathological diagnostic criterion, using the Delphi method. This criterion was found to be useful in improving concordance of BLI diagnosis.
  
  
  CONCLUSIONS
  A framework for pathological diagnostic criterion was developed by reviewing concordance and using the Delphi method. The criterion developed may serve as the basis for creating a standardised procedure for pathological diagnosis.
authors.affiliation: Pathology Division, Research Center for Innovative Oncology, National Cancer Center Hospital East, Kashiwa, Chiba, Japan.
authors.forename: Motohiro
authors.initials: M
authors.lastname: Kojima
authors.forename: Hideyuki
authors.initials: H
authors.lastname: Shimazaki
authors.forename: Keiichi
authors.initials: K
authors.lastname: Iwaya
authors.forename: Masayoshi
authors.initials: M
authors.lastname: Kage
authors.forename: Jun
authors.initials: J
authors.lastname: Akiba
authors.forename: Yasuo
authors.initials: Y
authors.lastname: Ohkura
authors.forename: Shinichiro
authors.initials: S
authors.lastname: Horiguchi
authors.forename: Kohei
authors.initials: K
authors.lastname: Shomori
authors.forename: Ryoji
authors.initials: R
authors.lastname: Kushima
authors.forename: Yoichi
authors.initials: Y
authors.lastname: Ajioka
authors.forename: Shogo
authors.initials: S
authors.lastname: Nomura
authors.forename: Atsushi
authors.initials: A
authors.lastname: Ochiai
mesh_terms: D000368:Aged; D014408:Biomarkers, Tumor / Q000378:metabolism; D001808:Blood Vessels / Q000473:pathology*; D003110:Colonic Neoplasms / Q000175:diagnosis* / Q000378:metabolism / Q000601:surgery; D003697:Delphi Technique; D005260:Female; D006801:Humans; D042601:Lymphatic Vessels / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D009361:Neoplasm Invasiveness; D009367:Neoplasm Staging; D015588:Observer Variation; D012004:Rectal Neoplasms / Q000175:diagnosis* / Q000378:metabolism / Q000601:surgery; D015203:Reproducibility of Results; D012955:Societies, Medical
chemical_list: D014408:Biomarkers, Tumor