title: Well-differentiated adenocarcinoma associated with ulcerative colitis.
abstract: OBJECTIVE
  Adenocarcinoma is known to be associated with ulcerative colitis, but the diagnosis is sometimes challenging, both clinically and pathologically.
  
  
  RESULTS
  We present a case of extremely well-differentiated adenocarcinoma associated with ulcerative colitis, in which preoperative diagnosis was not possible. Glands in biopsy specimens showed a serrated appearance that looked like low-grade dysplasia or regenerative mucosa. After an operation due to severe symptoms of stenosis, carcinoma was diagnosed. Tumor cells, especially in invasive glands, tended to show stronger immunoreactivity against anti-CK7, TNF-α and Aurora B antibodies compared to cells of mucosal lesion. Interestingly, CD44v6, one of the adhesion molecules, was less expressed in invasive glands, while those glands exhibited stronger expression of a disintegrin and metalloproteinase 17 (ADAM 17), one of the sheddases that cleaves an extracellular domain of CD44.
  
  
  CONCLUSIONS
  These observations appear interesting to consider the pathogenesis and to diagnose extremely well-differentiated adenocarcinoma in ulcerative colitis, although further investigation is needed.
authors.affiliation: Department of Surgical Pathology, Tokyo Women's Medical University, Tokyo, Japan; Department of Pathology, Tokyo Women's Medical University, Tokyo, Japan.
authors.forename: Tomoko
authors.initials: T
authors.lastname: Yamamoto
authors.affiliation: Department of Surgical Pathology, Tokyo Women's Medical University, Tokyo, Japan; Department of Pathology, Tokyo Women's Medical University, Tokyo, Japan.
authors.forename: Atsuko
authors.initials: A
authors.lastname: Hiroi
authors.affiliation: Department of Surgical Pathology, Tokyo Women's Medical University, Tokyo, Japan; Department of Pathology, Tokyo Women's Medical University, Tokyo, Japan.
authors.forename: Hiroko
authors.initials: H
authors.lastname: Itagaki
authors.affiliation: Department of Pathology, Tokyo Women's Medical University, Tokyo, Japan.
authors.forename: Yoichiro
authors.initials: Y
authors.lastname: Kato
authors.affiliation: Department of Medicine, Institute of Gastroenterology, Tokyo Women's Medical University, Tokyo, Japan.
authors.forename: Bunei
authors.initials: B
authors.lastname: Iizuka
authors.affiliation: Department of Surgery, Institute of Gastroenterology, Tokyo Women's Medical University, Tokyo, Japan.
authors.forename: Michio
authors.initials: M
authors.lastname: Itabashi
authors.affiliation: Department of Surgical Pathology, Tokyo Women's Medical University, Tokyo, Japan; Department of Pathology, Tokyo Women's Medical University, Tokyo, Japan.
authors.forename: Noriyuki
authors.initials: N
authors.lastname: Shibata
authors.affiliation: Department of Surgical Pathology, Tokyo Women's Medical University, Tokyo, Japan.
authors.forename: Yoji
authors.initials: Y
authors.lastname: Nagashima
keywords: CD44v6; CK7; TNF-α; Ulcerative colitis; extremely well-differentiated adenocarcinoma