title: Utility of tumor markers in determining resectability of pancreatic cancer.
abstract: OBJECTIVE
  Despite advances in preoperative radiologic imaging, a significant fraction of potentially resectable pancreatic cancers are found to be unresectable at laparotomy. We tested the hypothesis that preoperative serum levels of CA19-9 (cancer antigen) and carcinoembryonic antigen will identify patients with unresectable pancreatic cancer despite radiologic staging demonstrating resectable disease.
  
  
  METHODS
  Academic tertiary care referral center.
  
  
  METHODS
  From March 1, 1996, to July 31, 2002, 125 patients were identified who underwent surgical exploration for potentially resectable pancreatic cancer based on a preoperative computed tomographic scan; in 89 of them a preoperative tumor marker had been measured.
  
  
  METHODS
  Preoperative tumor markers (CA19-9 and carcinoembryonic antigen) were correlated with extent of disease at exploration. As CA19-9 is excreted in the biliary system, CA19-9 adjusted for the degree of hyperbilirubinemia was determined and analyzed.
  
  
  RESULTS
  Of the 89 patients, 40 (45%) had localized disease and underwent resection, 25 (28%) had locally advanced (unresectable) disease, and 24 (27%) had metastatic disease. The mean adjusted CA19-9 level was significantly lower in those with localized disease than those with locally advanced (63 vs 592; P =.003) or metastatic (63 vs 1387; P<.001) disease. When a threshold adjusted CA19-9 level of 150 was used, the positive predictive value for determination of unresectable disease was 88%. Carcinoembryonic antigen level was not correlated with extent of disease.
  
  
  CONCLUSIONS
  Among the patients with resectable pancreatic cancer based on preoperative imaging studies, those with abnormally high serum levels of CA19-9 may have unresectable disease. These patients may benefit from additional staging modalities such as diagnostic laparoscopy to avoid unnecessary laparotomy.
authors.affiliation: Department of Surgery, Division of Surgical Oncology, UC Davis Cancer Center, Sacramento, CA 95817, USA.
authors.forename: Michael G
authors.initials: MG
authors.lastname: Schlieman
authors.forename: Hung S
authors.initials: HS
authors.lastname: Ho
authors.forename: Richard J
authors.initials: RJ
authors.lastname: Bold
mesh_terms: D000230:Adenocarcinoma / Q000097:blood* / Q000000981:diagnostic imaging / Q000473:pathology / Q000601:surgery; D000368:Aged; D018395:CA-19-9 Antigen / Q000097:blood*; D002272:Carcinoembryonic Antigen / Q000097:blood*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D010190:Pancreatic Neoplasms / Q000097:blood* / Q000000981:diagnostic imaging / Q000473:pathology / Q000601:surgery; D011237:Predictive Value of Tests; D011300:Preoperative Care; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D014057:Tomography, X-Ray Computed
chemical_list: D018395:CA-19-9 Antigen; D002272:Carcinoembryonic Antigen