title: Cytokeratin 20 (CK20) and apomucin 1 (MUC1) expression in ampullary carcinoma: Correlation with tumor progression and prognosis.
abstract: BACKGROUND
  We assessed the expression of cytokeratin (CK) and apomucin (MUC) in ampullary carcinoma (AC) to develop a system for the classification of ACs on the basis of their clinical significance.
  
  
  METHODS
  We studied the expressions of CK7, CK20, MUC1, MUC2, MUC5AC, and MUC6 in 43 patients with ACs. Clinical data were obtained retrospectively by examining surgically resected ACs of the patients.
  
  
  RESULTS
  We classified the cases into 3 groups: tumors expressing CK20 and lacking MUC1 (intestinal type [I-type], 26%), tumors expressing MUC1 and lacking CK20 (pancreatobiliary type [PB-type], 35%), and those expressing or lacking both CK20 and MUC1 (other type [O-type], 39%). Eight (73%) of 11 I-type carcinomas, 3 (20%) of 15 PB-type carcinomas, and 4 (24%) of 17 O-type carcinomas were classified as pT1. The number of I-type carcinomas in the early tumor stages was significantly higher than the number of PB- and O-type carcinomas (p = 0.014 and p = 0.018, respectively). The 5-year survival rates for pT1, pT2, and pT3 tumors were 76%, 33%, and 22%, respectively (p < 0.001). Rates of MUC5AC and MUC6 coexpression for I-type, PB-type, and O-type tumors were 18%, 13%, and 53%, respectively. There was a significant correlation between MUC5AC and MUC6 coexpression and O-type characteristics (p = 0.031). The five-year survival rates for O-type ACs with and without MUC5AC and MUC6 coexpression were 71% and 17%, respectively (p = 0.048).
  
  
  CONCLUSIONS
  The immunohistochemical subtypes based on CK and MUC expression correlated with tumor progression. Gastric MUC5AC and MUC6 coexpression correlated with better prognosis for O-type ACs.
authors.affiliation: Department of Digestive and General Surgery, Shimane University Faculty of Medicine,89-1 Enyacho, Izumo, Shimane 693-8501, Japan.
authors.forename: Yasunari
authors.initials: Y
authors.lastname: Kawabata
authors.forename: Tsuneo
authors.initials: T
authors.lastname: Tanaka
authors.forename: Takashi
authors.initials: T
authors.lastname: Nishisaka
authors.forename: Touko
authors.initials: T
authors.lastname: Inao
authors.forename: Takeshi
authors.initials: T
authors.lastname: Nishi
authors.forename: Seiji
authors.initials: S
authors.lastname: Yano
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D014670:Ampulla of Vater / Q000737:chemistry* / Q000473:pathology / Q000601:surgery; D014408:Biomarkers, Tumor / Q000032:analysis*; D002277:Carcinoma / Q000737:chemistry* / Q000145:classification / Q000401:mortality / Q000473:pathology / Q000601:surgery; D016009:Chi-Square Distribution; D003138:Common Bile Duct Neoplasms / Q000737:chemistry* / Q000145:classification / Q000401:mortality / Q000473:pathology / Q000601:surgery; D018450:Disease Progression; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D007564:Japan; D053208:Kaplan-Meier Estimate; D053554:Keratin-20 / Q000032:analysis; D008297:Male; D008875:Middle Aged; D055271:Mucin 5AC / Q000032:analysis; D018396:Mucin-1 / Q000032:analysis*; D055272:Mucin-6 / Q000032:analysis; D009367:Neoplasm Staging; D012189:Retrospective Studies; D016896:Treatment Outcome
chemical_list: D014408:Biomarkers, Tumor; C507499:KRT20 protein, human; D053554:Keratin-20; C060192:MUC1 protein, human; C524678:MUC5AC protein, human; C524734:MUC6 protein, human; D055271:Mucin 5AC; D018396:Mucin-1; D055272:Mucin-6