title: Evaluation of serum and pleural levels of the tumor markers CEA, CYFRA21-1 and CA 15-3 in patients with pleural effusion.
abstract: OBJECTIVE
  To determine the levels of the tumor markers carcinoembryonic antigen (CEA), cytokeratin 19 fragment (CYFRA21-1) and carbohydrate antigen 15-3 (CA 15-3) in the blood and pleural fluid of patients with benign or malignant pleural effusion, evaluating the sensitivity of each marker in these fluids.
  
  
  METHODS
  We prospectively evaluated 85 patients with pleural effusion. The study of the pleural fluid observed the criteria established in the literature. Levels of the markers were determined using electrochemiluminescence. The sensitivity was determined on the condition that the specificity was > or = 90%.
  
  
  RESULTS
  Of the 85 cases, 36 (42.4%) were malignant, 30 (35.3%) were benign, and the results were inconclusive in 19 (22.3%). In the malignant cases, the CEA and CYFRA21-1 levels were higher in the pleural fluid than in the blood, which was not observed for CA 15-3. In the benign cases, the CYFRA21-1 levels were higher in the pleural fluid than in the blood, whereas the opposite was found for CEA and CA 15-3. There were significant differences between malignant and benign cases for all markers, in pleural fluid and blood. In the pleural fluid, the sensitivity of CEA, CYFRA21-1 and CA 15-3 was 69.4, 69.4 and 66.7%, respectively, and the combined sensitivity was 80.6%. In the blood, the sensitivity was 57.1%, 71.4% and 48.6% for CEA, CYFRA21-1 and CA 15-3, respectively, and the combined sensitivity was 77%.
  
  
  CONCLUSIONS
  The results suggest that these markers might be useful in the differentiation between malignant and benign pleural effusion.
authors.affiliation: Universidade de Pernambuco, Recife, PE, Brasil. isabella.coimbra@uol.com.br <coimbra@uol.com.br>
authors.forename: Isabella Coimbra
authors.initials: IC
authors.lastname: Wagner
authors.forename: Murilo José de Barros
authors.initials: MJ
authors.lastname: Guimarães
authors.forename: Lilian Karine Neves
authors.initials: LK
authors.lastname: da Silva
authors.forename: Francisco Montenegro
authors.initials: FM
authors.lastname: de Melo
authors.forename: Maria Tereza Cartaxo
authors.initials: MT
authors.lastname: Muniz
mesh_terms: D000328:Adult; D000951:Antigens, Neoplasm / Q000032:analysis* / Q000097:blood; D014408:Biomarkers, Tumor / Q000032:analysis* / Q000097:blood; D002272:Carcinoembryonic Antigen / Q000032:analysis* / Q000097:blood; D003937:Diagnosis, Differential; D004563:Electrochemistry; D004812:Epidemiologic Methods; D005260:Female; D006333:Heart Failure / Q000175:diagnosis; D006801:Humans; D053539:Keratin-19; D007633:Keratins / Q000032:analysis* / Q000097:blood; D008107:Liver Diseases / Q000175:diagnosis; D008163:Luminescent Measurements; D008297:Male; D008875:Middle Aged; D018396:Mucin-1 / Q000032:analysis* / Q000097:blood; D016066:Pleural Effusion, Malignant / Q000097:blood / Q000737:chemistry / Q000175:diagnosis*; D014397:Tuberculosis, Pulmonary / Q000175:diagnosis
chemical_list: D000951:Antigens, Neoplasm; D014408:Biomarkers, Tumor; D002272:Carcinoembryonic Antigen; D053539:Keratin-19; D018396:Mucin-1; C102012:antigen CYFRA21.1; D007633:Keratins