title: Adenoma with clear cell change of the large intestine.
abstract: OBJECTIVE
  Clear cell change of the large intestinal neoplasm is rare, and its character remains unclear. We report a case of the large intestinal adenoma with clear cell change with immunohistochemical and molecular studies to investigate whether the clear cell change is associated with a malignant progression of the adenoma.
  
  
  METHODS
  We studied the histochemical and immunohistochemical staining characteristics of the tumor by staining with hematoxylin-eosin, periodic acid-Schiff, alcian blue, and by immunostaining using antibodies against carcinoembryonic antigen, epithelial membrane antigen, p53, and Ki-67. The c-K-ras codon 12 point mutations were analyzed using a nonradioactive restriction fragment length polymorphism technique.
  
  
  RESULTS
  The tumor was composed of a typical tubular adenoma and a tubular adenoma with clear cytoplasm. The clear cytoplasm was negative by mucin stains. Immunohistochemically p53 was negative in both the components. Labeling index of Ki-67 showed no significant difference between the two components. No codon 12 mutation of c-K-ras gene was observed in both the components.
  
  
  CONCLUSIONS
  These findings suggest that the clear cell change of the tubular adenoma is not associated with a malignant progression in adenoma-carcinoma sequence involving c-K-ras and p53.
authors.affiliation: Second Department of Pathology, Hokkaido University School of Medicine, Sapporo, Japan.
authors.forename: H
authors.initials: H
authors.lastname: Suzuki
authors.forename: S
authors.initials: S
authors.lastname: Ohta
authors.forename: S
authors.initials: S
authors.lastname: Tokuchi
authors.forename: J
authors.initials: J
authors.lastname: Moriya
authors.forename: Y
authors.initials: Y
authors.lastname: Fujioka
authors.forename: K
authors.initials: K
authors.lastname: Nagashima
mesh_terms: D000236:Adenoma / Q000235:genetics / Q000473:pathology*; D002272:Carcinoembryonic Antigen / Q000032:analysis; D003110:Colonic Neoplasms / Q000235:genetics / Q000473:pathology*; D016158:Genes, p53; D011905:Genes, ras / Q000235:genetics; D006801:Humans; D007150:Immunohistochemistry; D019394:Ki-67 Antigen / Q000032:analysis; D008297:Male; D008875:Middle Aged; D009154:Mutation; D016133:Polymerase Chain Reaction; D012150:Polymorphism, Restriction Fragment Length
chemical_list: D002272:Carcinoembryonic Antigen; D019394:Ki-67 Antigen