title: Nonspecific cross-reacting antigen-50/90 (NCA-50/90) as a new tumor marker.
abstract: BACKGROUND
  The nonspecific cross-reacting antigen-50/90 (NCA-50/90) is a glycoprotein antigen which shares some antigenic determinants with carcinoembryonic antigen (CEA). No definite clinical value has been established for the measurement of NCA-50/90 in cancer patients.
  
  
  METHODS
  We established and evaluated a chemiluminescent enzyme immunoassay (CLEIA) specific for NCA-50/90 using two monoclonal antibodies.
  
  
  RESULTS
  No significant reactivity with 4 purified related antigens including CEA was found in the NCA-50/90 CLEIA. Serum samples (n = 572) from patients with malignant (n = 326) as well as from healthy individuals (n = 246) were analyzed by the NCA-50/90 CLEIA and by the established ACCESS CEA assay. The average sensitivity of NCA-50/90 for malignant disease was 40.8%, compared to 45.4% of CEA. Relatively high positive rates of NCA-50/90 were observed in sera from patients with lung cancer (72.0%), hepatoma (62.5%), pancreatic cancer (47.6%), breast cancer (35.6%), and colorectal cancer (34.5%). About 15% of patients with malignant disease were positive only for NCA-50/90. The levels of NCA-50/90 and CEA in sera from patients with malignant disease correlated only poorly.
  
  
  CONCLUSIONS
  The present study suggests that increases in blood levels of NCA-50/90 occur in a population of cancer patients which is different from those with elevated levels of CEA and that NCA-50/90 might be useful for NCA-50/90-positive, but CEA-negative patients.
authors.affiliation: First Department of Biochemistry, School of Medicine, Fukuoka University, Japan. kurokima@fukuoka-u-ac-jp
authors.forename: M
authors.initials: M
authors.lastname: Kuroki
authors.forename: H
authors.initials: H
authors.lastname: Matsushita
authors.forename: H
authors.initials: H
authors.lastname: Matsumoto
authors.forename: Y
authors.initials: Y
authors.lastname: Hirose
authors.forename: T
authors.initials: T
authors.lastname: Senba
authors.forename: T
authors.initials: T
authors.lastname: Yamamoto
mesh_terms: D000818:Animals; D000951:Antigens, Neoplasm / Q000097:blood* / Q000276:immunology; D014408:Biomarkers, Tumor / Q000097:blood* / Q000276:immunology; D015815:Cell Adhesion Molecules; D002850:Chromatography, Gel; D003429:Cross Reactions; D005069:Evaluation Studies as Topic; D005500:Follow-Up Studies; D006801:Humans; D007124:Immunoenzyme Techniques / Q000379:methods*; D008562:Membrane Glycoproteins / Q000097:blood* / Q000276:immunology; D051379:Mice; D009369:Neoplasms / Q000097:blood
chemical_list: D000951:Antigens, Neoplasm; D014408:Biomarkers, Tumor; D015815:Cell Adhesion Molecules; D008562:Membrane Glycoproteins