title: Conventional endoscopic features are not sufficient to differentiate small, early colorectal cancer.
abstract: OBJECTIVE
  To evaluate the depth of invasion of small, early colorectal cancers (ECCs) using conventional endoscopic features.
  
  
  METHODS
  From January 2005 to September 2011, colonoscopy cohort showed that a total of 72 patients with small colorectal cancers with the size less than 20 mm underwent colonoscopy at the Yonsei University College of Medicine, Seoul, South Korea. Among them, 8 patients were excluded due to incomplete medical records. Finally, a total of 64 ECCs with submucosa (SM) invasion and size less than 20 mm were included. One hundred fifty-two adenomas with size less than 20 mm were included as controls. Nine endoscopic features, including seven morphological findings (i.e., loss of lobulation, excavation, demarcated and depressed areas, stalk swelling, fullness, fold convergence, and bleeding ulcers), pit patterns, and non-lifting signs, were evaluated retrospectively. All endoscopic features were evaluated by two experienced endoscopists who have each performed over 1000 colonoscopies annually for more than five years without knowledge of the histology.
  
  
  RESULTS
  Among the morphological findings, the size of deep submucosal cancers was bigger than that of superficial lesions (16.9 mm vs 12.3 mm, P < 0.001). Also, demarcated depressed areas, stalk swelling, and fullness were more common in deep SM cancers than in superficial tumors (demarcated depressed areas: 52.0% vs 15.7%, P < 0.001; stalk swelling: 100% vs 4.2%, P < 0.001; fullness: 25.0% vs 0%, P = 0.001). Among deep SM cancers, 96% of polyps showed invasive pit patterns, whereas 19.4% of superficial tumors showed invasive pit patterns (P < 0.001). A positive non-lifting sign was more common in deep SM cancers (85.0% vs 28.6%, P < 0.001). Diagnostic accuracy of invasive morphology, invasive pit patterns, and non-lifting signs for deep SM cancers were 71%, 82%, and 75%, respectively.
  
  
  CONCLUSIONS
  Conventional endoscopic findings were insufficient to discriminate small, deep SM cancers from superficial SM cancers by white light, standard colonoscopy.
authors.affiliation: Wan Park, Bun Kim, Soo Jung Park, Jae Hee Cheon, Tae Il Kim, Won Ho Kim, Sung Pil Hong, Department of Internal Medicine and Institute of Gastroenterology, Yonsei University College of Medicine, Seoul 120-752, South Korea.
authors.forename: Wan
authors.initials: W
authors.lastname: Park
authors.affiliation: Wan Park, Bun Kim, Soo Jung Park, Jae Hee Cheon, Tae Il Kim, Won Ho Kim, Sung Pil Hong, Department of Internal Medicine and Institute of Gastroenterology, Yonsei University College of Medicine, Seoul 120-752, South Korea.
authors.forename: Bun
authors.initials: B
authors.lastname: Kim
authors.affiliation: Wan Park, Bun Kim, Soo Jung Park, Jae Hee Cheon, Tae Il Kim, Won Ho Kim, Sung Pil Hong, Department of Internal Medicine and Institute of Gastroenterology, Yonsei University College of Medicine, Seoul 120-752, South Korea.
authors.forename: Soo Jung
authors.initials: SJ
authors.lastname: Park
authors.affiliation: Wan Park, Bun Kim, Soo Jung Park, Jae Hee Cheon, Tae Il Kim, Won Ho Kim, Sung Pil Hong, Department of Internal Medicine and Institute of Gastroenterology, Yonsei University College of Medicine, Seoul 120-752, South Korea.
authors.forename: Jae Hee
authors.initials: JH
authors.lastname: Cheon
authors.affiliation: Wan Park, Bun Kim, Soo Jung Park, Jae Hee Cheon, Tae Il Kim, Won Ho Kim, Sung Pil Hong, Department of Internal Medicine and Institute of Gastroenterology, Yonsei University College of Medicine, Seoul 120-752, South Korea.
authors.forename: Tae Il
authors.initials: TI
authors.lastname: Kim
authors.affiliation: Wan Park, Bun Kim, Soo Jung Park, Jae Hee Cheon, Tae Il Kim, Won Ho Kim, Sung Pil Hong, Department of Internal Medicine and Institute of Gastroenterology, Yonsei University College of Medicine, Seoul 120-752, South Korea.
authors.forename: Won Ho
authors.initials: WH
authors.lastname: Kim
authors.affiliation: Wan Park, Bun Kim, Soo Jung Park, Jae Hee Cheon, Tae Il Kim, Won Ho Kim, Sung Pil Hong, Department of Internal Medicine and Institute of Gastroenterology, Yonsei University College of Medicine, Seoul 120-752, South Korea.
authors.forename: Sung Pil
authors.initials: SP
authors.lastname: Hong
mesh_terms: D000236:Adenoma / Q000175:diagnosis* / Q000473:pathology*; D000368:Aged; D003113:Colonoscopy; D015179:Colorectal Neoplasms / Q000175:diagnosis* / Q000473:pathology*; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009361:Neoplasm Invasiveness; D015203:Reproducibility of Results; D056910:Republic of Korea; D012189:Retrospective Studies
keywords: Colonoscopy; Colorectal neoplasms; Differential diagnosis