title: Cyst fluid carcinoembryonic antigen is an accurate diagnostic marker of pancreatic mucinous cysts.
abstract: OBJECTIVE
  Endoscopic ultrasound (EUS) may offer a diagnostic tool through the combination of imaging and guided fine-needle aspiration of pancreatic cysts. The purpose of this investigation was to determine the most accurate test for differentiating mucinous from nonmucinous cysts.
  
  
  METHODS
  The results of EUS imaging, cytology, and cyst fluid biochemical markers were prospectively collected and compared in a large single-center study (776 patients) using histology or malignant cytology as the final diagnostic standard in 198 patients.
  
  
  RESULTS
  The mean cyst fluid carcinoembryonic antigen (CEA) was greater in mucinous cysts (4703.0 ng/mL) compared with nonmucinous cysts (25.8 ng/mL) (P = 0.008). When using the optimal cutoff value of 109.9 ng/mL, the CEA was more accurate (86%, receiver operating characteristic area = 0.928) than EUS imaging (48%) and cytology (58%) in predicting a mucinous cyst (P < 0.0001). Malignant cysts had a mean cyst fluid CEA value (2558.2 ng/mL) similar to benign cysts (4700.2 ng/mL). Cytology (75%) more accurately diagnosed malignant cysts than EUS (66%) and CEA (62%) (P < 0.05).
  
  
  CONCLUSIONS
  Cyst fluid CEA concentration provides a highly accurate test for the diagnosis of a mucinous cyst, but does not distinguish benign from malignant cysts. Cytology is the most accurate test for the diagnosis of a malignant cyst.
authors.affiliation: Gastrointestinal Unit, Massachusetts General Hospital, Boston, MA 02116, USA.
authors.forename: Sevdenur
authors.initials: S
authors.lastname: Cizginer
authors.forename: Brian G
authors.initials: BG
authors.lastname: Turner
authors.forename: Brian
authors.initials: B
authors.lastname: Turner
authors.forename: A Reyyan
authors.initials: AR
authors.lastname: Bilge
authors.forename: Cetin
authors.initials: C
authors.lastname: Karaca
authors.forename: Martha B
authors.initials: MB
authors.lastname: Pitman
authors.forename: William R
authors.initials: WR
authors.lastname: Brugge
mesh_terms: D000368:Aged; D014408:Biomarkers, Tumor / Q000032:analysis*; D044963:Biopsy, Fine-Needle; D001900:Boston; D002272:Carcinoembryonic Antigen / Q000032:analysis*; D020420:Cyst Fluid / Q000737:chemistry*; D003937:Diagnosis, Differential; D019160:Endosonography; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D018297:Neoplasms, Cystic, Mucinous, and Serous / Q000737:chemistry / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000473:pathology; D010181:Pancreatic Cyst / Q000737:chemistry / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000473:pathology; D010190:Pancreatic Neoplasms / Q000737:chemistry / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000473:pathology; D011237:Predictive Value of Tests; D011446:Prospective Studies; D012372:ROC Curve; D011863:Radioimmunoassay; D012680:Sensitivity and Specificity
chemical_list: D014408:Biomarkers, Tumor; D002272:Carcinoembryonic Antigen