Does Concurrent Cholestasis Alter the Prognostic Value of Preoperatively Elevated CA19-9 Serum Levels in Patients with Pancreatic Head Adenocarcinoma?

Pancreatic adenocarcinoma (PDAC) patients with preoperative carbohydrate antigen 19-9 (CA19-9) serum levels higher than 500 U/ml are classified as biologically borderline resectable (BR-B). To date, the impact of cholestasis on preoperative CA19-9 serum levels in these patients has remained unquantified.

Data on 3079 oncologic pancreatic resections due to PDAC that were prospectively acquired by the German Study, Documentation and Quality (StuDoQ) registry were analyzed in relation to preoperative CA19-9 and bilirubin serum values. Preoperative CA19-9 values were adjusted according to the results of a multivariable linear regression analysis of pathologic parameters, bilirubin, and CA19-9 values.

Of 1703 PDAC patients with tumor located in the pancreatic head, 420 (24.5 %) presented with a preoperative CA19-9 level higher than 500 U/ml. Although receiver operating characteristics (ROC) analysis failed to determine exact CA19-9 cut-off values for prognostic indicators (R and N status), the T, N, and G status; the UICC stage; and the number of simultaneous vein resections increased with the level of preoperative CA19-9, independently of concurrent cholestasis. After adjustment of preoperative CA19-9 values, 18.5 % of patients initially staged as BR-B showed CA19-9 values below 500 U/ml. However, the postoperative pathologic results for these patients did not change compared with the patients who had CA19-9 levels higher than 500 U/ml after bilirubin adjustment.

In this multicenter dataset of PDAC patients, elevation of preoperative CA19-9 correlated with well-defined prognostic pathologic parameters. Bilirubin adjustment of CA19-9 is feasible but does not affect the prognostic value of CA19-9 in jaundiced patients.