title: CA 19-9 as a marker in addition to CEA to monitor colorectal cancer.
abstract: BACKGROUND
  Carcinoembryonic antigen is the commonly used tumor marker in patients with colorectal cancer, and CA 19-9 might be an additional marker. The aim of this retrospective study was to investigate whether CA 19-9 levels can be used to monitor the disease process in patients with colorectal cancer who had no elevated CEA levels. The secondary aim was to determine if preoperative increased levels of CEA and CA 19-9 were associated with mortality.
  
  
  METHODS
  Two sets of data from patients with histologically confirmed colorectal cancer, were included in a single-center study. First, patients with a minimum of 3 serial measurements of CA 19-9 and CEA tumor markers were related to the clinical course of their disease. Second, patients with preoperative levels of CEA and CA 19-9 were related to survival.
  
  
  RESULTS
  In patients with colorectal cancer and 3 serial measurements of tumor markers, 7.3% had only increased CA 19-9 levels without increased CEA levels, and 55.4% of the patients had an increase of CA 19-9 and CEA levels. In the patients with available preoperative markers, patients with only an increase of CA 19-9 had a significantly decreased 5-year survival compared with patients with an increase of only CEA (P = .013).
  
  
  CONCLUSIONS
  CA 19-9 can be used as additional marker to follow the disease process in patients with colorectal cancer without an increase in CEA level. Patients with preoperative increased CA 19-9 level had a poorer 5-year survival than patients with preoperative increased CEA levels.
authors.affiliation: Department of Oncology, Internal Medicine, Kennemer Gasthuis, Haarlem, The Netherlands; Faculty of Medicine, VU Medical Centre, Amsterdam, The Netherlands.
authors.forename: Jolanda
authors.initials: J
authors.lastname: Stiksma
authors.affiliation: Department of Oncology, Internal Medicine, Kennemer Gasthuis, Haarlem, The Netherlands; Linnaeus Institute, Kennemer Gasthuis, Haarlem, The Netherlands; Landsteiner Institute, Medical Center Haaglanden, The Hague, The Netherlands.
authors.forename: Diana C
authors.initials: DC
authors.lastname: Grootendorst
authors.affiliation: Department of Oncology, Internal Medicine, Kennemer Gasthuis, Haarlem, The Netherlands. Electronic address: pw.vdlinden@kg.nl.
authors.forename: Peter Willem G
authors.initials: PW
authors.lastname: van der Linden
mesh_terms: D000368:Aged; D014408:Biomarkers, Tumor / Q000097:blood*; D018395:CA-19-9 Antigen / Q000097:blood*; D002272:Carcinoembryonic Antigen / Q000097:blood*; D015179:Colorectal Neoplasms / Q000097:blood* / Q000401:mortality / Q000473:pathology; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007118:Immunoassay; D008113:Liver Neoplasms / Q000097:blood* / Q000401:mortality / Q000556:secondary; D008175:Lung Neoplasms / Q000097:blood* / Q000401:mortality / Q000556:secondary; D008207:Lymphatic Metastasis; D008297:Male; D009367:Neoplasm Staging; D011379:Prognosis; D012189:Retrospective Studies; D015996:Survival Rate
chemical_list: D014408:Biomarkers, Tumor; D018395:CA-19-9 Antigen; D002272:Carcinoembryonic Antigen
keywords: CA19-9; CEA; Follow-up; Pre-operative; Tumor markers