title: Assessment of the value of preoperative serum levels of CA 242 and CEA in the staging and postoperative survival of colorectal adenocarcinoma patients.
abstract: BACKGROUND
  CEA is the most frequently used tumor marker in colorectal cancer. There may be an improvement in its efficacy when used in association with CA 242.
  
  
  OBJECTIVE
  The purpose of this study was to evaluate the efficacy of preoperative serum levels of the tumor markers CA 242 and CEA in the staging and postoperative follow-up of colorectal adenocarcinoma patients.
  
  
  METHODS
  Of a series of 134 patients with colorectal adenocarcinomas 90 underwent radical surgery and 44 palliative surgery. The control group consisted of 22 organ donors. The cutoff serum levels utilized were 5 ng/mL for CEA and 20 U/mL for CA 242. The mortality during follow-up was recorded in order to determine the duration of survival. The data were submitted to statistical analysis using diagnostic tests, the chi-square test, survival analysis (Kaplan and Meier) and ROC curves. A significance level of p < or = 0.05 was applied.
  
  
  RESULTS
  The sensitivity of CEA in Dukes' stages A, B, C and D was 27.8%, 32.4%, 32.1% and 66.7%, respectively. The sensitivity of CA 242 was 11.1%, 16.2%, 30.8% and 50%. When both markers were combined, the sensitivity was 33.3%, 48.6%, 40.7% and 72.5%. In the group of patients who underwent radical surgery the mean survival was 60.47 months for those with high preoperative CEA levels, 52.22 months for those with high preoperative CA 242 levels, and 44.80 months for those with elevated levels of both markers. There was a statistically significant difference in survival between patients undergoing radical surgery with elevated CA 242 levels, especially when CEA was also elevated, and patients without elevated CA 242.
  
  
  CONCLUSIONS
  Preoperative serum levels of CA 242 showed less efficacy than CEA levels for the staging of colorectal adenocarcinoma patients. Elevated preoperative serum levels of CA 242 alone were related to poor survival, especially in association with high levels of CEA.
authors.affiliation: Surgical Gastroenterology Division, Escola Paulista de Medicina, Federal University of São Paulo, São Paulo, Brazil. subong@uol.com.br
authors.forename: S B
authors.initials: SB
authors.lastname: Kim
authors.forename: L C
authors.initials: LC
authors.lastname: Fernandes
authors.forename: S S
authors.initials: SS
authors.lastname: Saad
authors.forename: D
authors.initials: D
authors.lastname: Matos
mesh_terms: D000230:Adenocarcinoma / Q000097:blood / Q000175:diagnosis* / Q000401:mortality; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015295:Antigens, Tumor-Associated, Carbohydrate / Q000097:blood*; D014408:Biomarkers, Tumor; D002272:Carcinoembryonic Antigen / Q000097:blood*; D016022:Case-Control Studies; D015179:Colorectal Neoplasms / Q000097:blood* / Q000175:diagnosis* / Q000401:mortality; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D012372:ROC Curve; D012680:Sensitivity and Specificity; D013997:Time Factors; D016896:Treatment Outcome
chemical_list: D015295:Antigens, Tumor-Associated, Carbohydrate; D014408:Biomarkers, Tumor; C074601:CA 242 antigen; D002272:Carcinoembryonic Antigen