title: Expression of cytokeratin 20 indicates invasive histological phenotype in poorly differentiated colorectal adenocarcinoma.
abstract: OBJECTIVE
  Cytokeratin (CK) 20 expression is an independent prognostic factor of poorly differentiated adenocarcinoma (PDA) of the colon and rectum. We aimed to investigate the mechanism of its involvement through a clinicopathological study.
  
  
  METHODS
  We analyzed 156 surgically resected PDAs, which were sub-classified as solid type (Por1) showing expansive growth, or non-solid type (Por2) showing infiltrative growth. Associations of CK20 expression with morphological features and molecular markers were analyzed.
  
  
  RESULTS
  CK20(+) PDA (n=91) was associated with more advanced disease stage and unfavorable prognosis compared with CK20(-) PDA (n=65). Pathologically, CK20(+) PDA was significantly associated with p53 overexpression, Por2, abundant fibrous stroma, and stepwise de-differentiation, while CK20(-) PDA was significantly associated with mismatch repair deficiency, Por1, sparse fibrous stroma, and de novo histogenesis.
  
  
  CONCLUSIONS
  CK20 expression in PDA is closely associated with invasive histological features, providing prognostic significance, and may also point to a specific histogenetic pathway.
authors.affiliation: Department of Pathology, Dokkyo Medical University Koshigaya Hospital, 2-1-50 Minami-Koshigaya, Koshigaya, Saitama 343-8555, Japan. yimai@s3.dion.ne.jp.
authors.forename: Yasuo
authors.initials: Y
authors.lastname: Imai
authors.forename: Hidetsugu
authors.initials: H
authors.lastname: Yamagishi
authors.forename: Kazunori
authors.initials: K
authors.lastname: Fukuda
authors.forename: Takuya
authors.initials: T
authors.lastname: Okamura
authors.forename: Yuko
authors.initials: Y
authors.lastname: Ono
authors.forename: Shinichi
authors.initials: S
authors.lastname: Ban
authors.forename: Tohru
authors.initials: T
authors.lastname: Inoue
authors.forename: Yoshihiko
authors.initials: Y
authors.lastname: Ueda
mesh_terms: D000230:Adenocarcinoma / Q000378:metabolism / Q000401:mortality / Q000473:pathology*; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D014408:Biomarkers, Tumor / Q000378:metabolism*; D002454:Cell Differentiation; D015179:Colorectal Neoplasms / Q000378:metabolism / Q000401:mortality / Q000473:pathology*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007124:Immunoenzyme Techniques; D053554:Keratin-20 / Q000378:metabolism*; D008207:Lymphatic Metastasis; D008297:Male; D008875:Middle Aged; D009361:Neoplasm Invasiveness; D009367:Neoplasm Staging; D010641:Phenotype; D011379:Prognosis; D015996:Survival Rate
chemical_list: D014408:Biomarkers, Tumor; D053554:Keratin-20
keywords: Poorly differentiated adenocarcinoma; colon; cytokeratin 20; non-solid type (Por2); solid type (Por1)