title: Expression of CEA, CA19-9, CA125, and EpCAM in pseudomyxoma peritonei.
abstract: Pseudomyxoma peritonei is a fatal clinical syndrome with mucinous tumor cells disseminated into peritoneal cavity and secreting abundant mucinous ascites. The serum tumor markers CEA, CA19-9, and CA125 are used to monitor pseudomyxoma peritonei remission, but their expression at tissue level has not been well characterized. Herein, we analyzed expression of these proteins and the adenocarcinoma marker EpCAM in 92 appendix-derived pseudomyxoma peritonei tumors by immunohistochemistry. All tumors were found to ubiquitously express CEA and EpCAM. In the majority of the tumors (94.6%), CEA showed polarized immunostaining, but in 5 aggressive high-grade tumors containing numerous signet ring cells, a nonpolarized staining was detected. We found preoperative CEA serum values to correlate with peritoneal cancer index. However, the serum values of the advanced cases with nonpolarized staining pattern were normal, and the patients died within 5 years after diagnosis. Thus, serum CEA measurements did not reflect aggressiveness of these tumors. CA19-9 showed strong immunopositivity in most of the tumors (91.3%), and mutated enzyme FUT3 was demonstrated from the cases showing negative or weak staining. CA125 was infrequently expressed by tumor cells (focal staining in 6.5% of the cases), but in most of the cases (79.3%), adjacent nonneoplastic mesothelial cells showed immunopositivity. As a conclusion, CEA and EpCAM are invariably expressed by pseudomyxoma peritonei tumor cells and could be exploited to targeted therapies against this malignancy.
authors.affiliation: Pathology, Research Programs Unit, University of Helsinki and Helsinki University Hospital, 00014, Helsinki, Finland. Electronic address: pirjo.nummela@helsinki.fi.
authors.forename: Pirjo
authors.initials: P
authors.lastname: Nummela
authors.affiliation: Pathology, Research Programs Unit, University of Helsinki and Helsinki University Hospital, 00014, Helsinki, Finland.
authors.forename: Hannele
authors.initials: H
authors.lastname: Leinonen
authors.affiliation: Department of Surgery, Helsinki University Central Hospital, 00029, Helsinki, Finland; Department of Urology, Helsinki University Central Hospital, 00029, Helsinki, Finland.
authors.forename: Petrus
authors.initials: P
authors.lastname: Järvinen
authors.affiliation: Pathology, Research Programs Unit, University of Helsinki and Helsinki University Hospital, 00014, Helsinki, Finland.
authors.forename: Alexandra
authors.initials: A
authors.lastname: Thiel
authors.affiliation: Department of Surgery, Helsinki University Central Hospital, 00029, Helsinki, Finland.
authors.forename: Heikki
authors.initials: H
authors.lastname: Järvinen
authors.affiliation: Department of Surgery, Helsinki University Central Hospital, 00029, Helsinki, Finland.
authors.forename: Anna
authors.initials: A
authors.lastname: Lepistö
authors.affiliation: Pathology, Research Programs Unit, University of Helsinki and Helsinki University Hospital, 00014, Helsinki, Finland; Pathology, Research Programs Unit and HUSLAB, University of Helsinki and Helsinki University Hospital, 00029, Helsinki, Finland. Electronic address: ari.ristimaki@helsinki.fi.
authors.forename: Ari
authors.initials: A
authors.lastname: Ristimäki
mesh_terms: D001706:Biopsy; D018394:CA-125 Antigen / Q000032:analysis*; D018395:CA-19-9 Antigen / Q000032:analysis*; D002272:Carcinoembryonic Antigen / Q000032:analysis* / Q000097:blood; D000071858:Epithelial Cell Adhesion Molecule / Q000032:analysis*; D005647:Fucosyltransferases / Q000235:genetics; D006801:Humans; D007150:Immunohistochemistry; D008565:Membrane Proteins / Q000032:analysis*; D009154:Mutation; D060787:Neoplasm Grading; D010534:Peritoneal Neoplasms / Q000737:chemistry* / Q000235:genetics / Q000401:mortality / Q000473:pathology; D011237:Predictive Value of Tests; D011553:Pseudomyxoma Peritonei / Q000235:genetics / Q000378:metabolism* / Q000401:mortality / Q000473:pathology; D013997:Time Factors
chemical_list: D018394:CA-125 Antigen; D018395:CA-19-9 Antigen; D002272:Carcinoembryonic Antigen; C499379:EPCAM protein, human; D000071858:Epithelial Cell Adhesion Molecule; C451759:MUC16 protein, human; D008565:Membrane Proteins; D005647:Fucosyltransferases; C019818:3-galactosyl-N-acetylglucosaminide 4-alpha-L-fucosyltransferase
keywords: CA125; CA19-9; CEA; EpCAM; Immunohistochemistry; Pseudomyxoma peritonei