Do metabolic alterations serve as biochemical markers in the diagnosis of malignant biliary obstruction? An observational study

The aim of this study was to investigate the changes in serum lipid profiles in biliary obstruction associated with benign and malignant conditions and to find whether they can be used as adjunctive biochemical tumor markers in the differential diagnosis.

One hundred and twenty patients (60 malignant, 60 benign) who underwent endoscopic retrograde cholangiopancreatography with the clinical picture of intrahepatic and extrahepatic cholestasis were reviewed in the period from January to July 2008.

In the malignant group, significantly higher cholesterol (P<0.001), low-density lipoprotein (P<0.001), and triglycerides (P<0.001) were observed, whereas high-density lipoprotein (P<0.001) levels were lower. The receiver operating characteristic analysis showed that high-density lipoprotein 19.5 mg/dl or less [sensitivity: 88.3%, specificity: 83.3%, area under the curve: 0.906 (0.851-0.961), P<0.001] and total to -high-density lipoprotein cholesterol ratio at least 17.7 [sensitivity: 80.0%, specificity: 93.1%, area under the curve: 0.921 (0.871-0.971)] were strong predictors of malignant biliary obstruction.

Serum lipid profile may be used as an adjunctive marker to identify malignant causes of the obstructive jaundice.