Clinical discrimination between choledocholithiasis and biliopancreatic malignancy based on a new biochemical model.

Abstract

Purpose: This study aims to establish predictive laboratory
tests, which could confidently assist for an initial clinical discrimination
of choledocholithiasis from biliopancreatic malignancy,
before an invasive endoscopic or surgical diagnosis.
Results: A total of 174 patients, who underwent ERCP
were analyzed. Patients with final diagnosis of choledocholithiasis
(137 patients) and biliopancreatic adenocarcinoma
(37 patients) had their biochemistry parameters compared
using Mann-Whittney test. Cut-off values for each parameter
were defined. The cut-off values that provided the best
trade-off between sensitivity and specificity were: 8.65 mg/
dL for total bilirubin, 276 U/L for serum alkaline phosphatase
and 306 IU/ml for CA19-9. A patient most probably
(96%) suffers from cancer, if he has high incriminating values
in all these three parameters. Conclusions: A simple, reproducible,
easy-to-obtain predictive model with laboratory
tests, successfully differentiates choledocholithiasis from
malignant biliopancreatic diseases and could be useful for a
more cost-effective investigation and treatment of patients
with such pathology.