title: Small, flat colorectal neoplasias in long-standing ulcerative colitis detected by high-resolution electronic video endoscopy.
abstract: BACKGROUND
  High-resolution video endoscopy complemented with chromoscopy allows for more detailed visualization of the colonic mucosal surface.
  
  
  METHODS
  Using high-resolution video endoscopy and chromoscopy, we investigated 85 patients with extensive ulcerative colitis with a disease duration of at least 10 years who were taking part in a cancer surveillance program.
  
  
  RESULTS
  In 38 of the 85 patients, 104 polyps were detected at endoscopy. Seventy-seven (74%) of the 104 polyps were endoscopically flat, 21 (20%) were sessile, 3 (3%) were pedunculated, and 3 (3%) had no recorded morphology. Twenty-three (22%) polyps were neoplastic (15 flat, 5 sessile, 2 pedunculated, 1 not recorded). Low-grade dysplasia was found in 21 of the 23 neoplastic polyps and high-grade dysplasia in the remaining 2 (1 flat tubular adenoma and 1 sessile villous adenoma with invasive growth). Flat polyps were small, with a diameter of 5 mm or less in 73% (n = 56) of cases. At histology flat polyps revealed either flat adenomas (n = 11; 14.3%), tubular or villous structures with dysplastic cells at the lower part of the crypts (n = 4; 5.2%), flat hyperplastic polyps (n = 26; 34%), inflammatory mucosa (n = 5; 6.5%), or mucosa in remission (n = 31; 40%).
  
  
  CONCLUSIONS
  The use of high-resolution video endoscopy complemented with chromoscopy in ulcerative colitis enables the detection of flat neoplastic polyps. The existence of those hitherto undetected neoplasms in ulcerative colitis and their possible role in the histogenesis of colorectal cancer in ulcerative colitis deserve further investigation.
authors.affiliation: Department of Diagnostic Radiology, Karolinska Hospital, Stockholm, Sweden.
authors.forename: E
authors.initials: E
authors.lastname: Jaramillo
authors.forename: M
authors.initials: M
authors.lastname: Watanabe
authors.forename: R
authors.initials: R
authors.lastname: Befrits
authors.forename: E
authors.initials: E
authors.lastname: Ponce de León
authors.forename: C
authors.initials: C
authors.lastname: Rubio
authors.forename: P
authors.initials: P
authors.lastname: Slezak
mesh_terms: D000236:Adenoma / Q000473:pathology; D018253:Adenoma, Villous / Q000473:pathology; D000328:Adult; D000368:Aged; D003093:Colitis, Ulcerative / Q000473:pathology*; D003111:Colonic Polyps / Q000473:pathology*; D003113:Colonoscopy / Q000379:methods*; D015179:Colorectal Neoplasms / Q000473:pathology*; D005260:Female; D006801:Humans; D007413:Intestinal Mucosa / Q000473:pathology; D008297:Male; D008875:Middle Aged; D014741:Video Recording