title: KL-6 mucin is a useful immunohistochemical marker for cholangiocarcinoma.
abstract: This study aimed to clarify the clinical significance of the expression of KL-6 mucin, a type of MUC1, in primary liver cancer. Tissue specimens were collected from 21 patients with cholangiocarcinoma (CC), 78 with hepatocellular carcinoma (HCC), and 12 with combined hepatocellular and cholangiocarcinoma (cHCC-CC). Immunohistochemical analysis was done using a monoclonal antibody for KL-6 mucin as well as antibodies for Hep1 or CK7. KL-6 staining was positive in all the CC tissues examined, while it was not positive in any of the HCC tissues. Similar selectivity of KL-6 staining was also observed in the cHCC-CC specimens, and the cholangiocellular tissue could be clearly delineated by KL-6 staining. In contrast, 79.5% of HCC specimens and 25.0% of cHCC-CC specimens were positive for Hep1 in the hepatocellular tissues, while none of the CC or cHCC-CC specimens were positive in the cholangiocellular tissues. Staining for CK7 was positive in 95.2% of CC and 35.9% of HCC specimens, while 58.3 and 25.0% of cHCC-CC specimens displayed positivity for CK7 in the cholangiocellular and hepatocellular tissues, respectively. These results suggest that KL-6 may be a useful tumor marker for distinguishing CC from HCC. In addition, the high selectivity of KL-6 for cholangiocallular tissue may help to provide information for deciding the clinical strategy in cHCC-CC patients.
authors.affiliation: Hepato-Biliary-Pancreatic Surgery Division, Department of Surgery, Graduate School of Medicine, The University of Tokyo, Bunkyo-ku, Tokyo 113-8655, Japan. tang-sur@h.u-tokyo.ac.jp
authors.forename: Wei
authors.initials: W
authors.lastname: Tang
authors.forename: Qian
authors.initials: Q
authors.lastname: Guo
authors.forename: Xianjun
authors.initials: X
authors.lastname: Qu
authors.forename: Yoshinori
authors.initials: Y
authors.lastname: Inagaki
authors.forename: Yasuji
authors.initials: Y
authors.lastname: Seyama
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Midorikawa
authors.forename: Ruoyan
authors.initials: R
authors.lastname: Gai
authors.forename: Norihiro
authors.initials: N
authors.lastname: Kokudo
authors.forename: Yasuhiko
authors.initials: Y
authors.lastname: Sugawara
authors.forename: Munehiro
authors.initials: M
authors.lastname: Nakata
authors.forename: Masatoshi
authors.initials: M
authors.lastname: Makuuchi
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000951:Antigens, Neoplasm / Q000032:analysis*; D001650:Bile Duct Neoplasms / Q000175:diagnosis* / Q000473:pathology; D014408:Biomarkers, Tumor / Q000032:analysis*; D006528:Carcinoma, Hepatocellular / Q000175:diagnosis / Q000473:pathology; D018281:Cholangiocarcinoma / Q000175:diagnosis* / Q000473:pathology; D003937:Diagnosis, Differential; D005260:Female; D022781:Hepatocytes / Q000276:immunology; D006801:Humans; D007150:Immunohistochemistry; D053552:Keratin-7 / Q000032:analysis; D008113:Liver Neoplasms / Q000175:diagnosis / Q000473:pathology; D008297:Male; D008875:Middle Aged; D018396:Mucin-1; D009077:Mucins / Q000032:analysis*
chemical_list: D000951:Antigens, Neoplasm; D014408:Biomarkers, Tumor; D053552:Keratin-7; C060192:MUC1 protein, human; D018396:Mucin-1; D009077:Mucins