Value of preoperative serum CA 19-9 levels in predicting resectability for pancreatic cancer

Background: Pancreatic cancer carries a poor prognosis; at operation approximately 25% of patients will be found to have unresectable tumours even though CT has demonstrated that they are resectable. At our tertiary care centre, we wished to find out if there is an optimum cut-off value for the CA 19-9 level preoperatively that will indicate that the pancreatic cancer is unresectable despite radiologic imaging that suggests otherwise according to receiver operating characteristic (ROC) curve analysis. Methods: Preoperative demographic data, clinical features and serum CA 19-9 levels were reviewed for 51 patients with pancreatic cancer who underwent laparotomy between 1998 and 2003. Preoperatively, resectability was determined from a complete history, physical examination and radiologic imaging. An ROC curve was constructed for the CA 19-9 levels. The sensitivity, specificity, positive and negative predictive values of CA 19-9 were calculated with several cut-off points. Results: There were 18 (36%) resectable and 33 (64%) unresectable pancreatic cancers. The mean CA 19-9 level was 68.8 U/mL in the resectable group and 622 U/mL in unresectable group. When a CA 19-9 level of 256.4 U/mL was used as a cutoff point, the specificity and sensitivity was 92.3% and 82.4% respectively. Conclusion: Preoperative CA 19-9 levels may be a useful marker for determining preoperatively which patients have unresectable disease despite the demonstration on CT of resectable disease.