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Perineural invasion and preoperative serum CA19-9 as predictors of survival in biliary tract cancer.

BACKGROUND
Billiary tract cancer requires invasive surgical procedures for cure, and the risk factors related to patient prognosis remain controversial.


PATIENTS AND METHODS
Out of the 111 patients who underwent resection of extrahepatic biliary tract tumors from 1986 to 2010, the records for 88 with both ampullary and extrahepatic bile duct cancer, which included all information for evaluation of the clinicopathological factors, were employed in a multivariate analysis.


RESULTS
On univariate analysis, significant prognostic factors of poor survival unrelated to TNM factors were preoperative biliary drainage, high preoperative CA19-9 value, high preoperative CEA value, lymphatic invasion, perineural invasion, macroscopic growth pattern, histology, operative procedures (surgery), tumor persistence, high postoperative CA19-9 value, and postoperative chemotherapy. On multivariate analysis, perineural invasion (p=0.025) was the only prognostic factor independent of stage, for survival of patients with biliary tract cancer including ampullary cancer. When ampullary cancer was excluded, both perineural invasion and preoperative CA19-9 were the remaining prognostic factors independent of stage. The combination of both factors can very accurately identify long-term and short-term survivors of biliary tract cancer.


CONCLUSION
The present study, to our knowledge, for the first time shows that both perineural invasion and preoperative CA19-9 are important prognostic factors in biliary tract cancer, and this would be beneficial for clinical clarification of the optimal strategies for this type of cancer.