Circulating carcinoembryonic antigen (CEA) levels and their relation to liver function test values were studied in 29 jaundiced patients with benign extrahepatic biliary tract obstruction and inflammation. During the obstructive and inflammatory phase, 15 (52%) of the patients had CEA levels greater than 2.5 ng/ml. Elevated CEA levels were associated more frequently with common bile duct stones (and cholangitis) than with gallbladder stones (and cholecystitis) alone, although this difference was not statistically significant. The former often had values greater than 5.0 ng/ml. The highest values were found in two patients with liver abscesses. The CEA levels returned to normal following relief of obstruction in seven of ten patients and increased in two patients who had progressive inflammation. Serum alkaline phosphatase and bilirubin levels were significantly higher in the patients with elevated CEA levels (P <.05). Serum alkaline phosphatase levels showed a significant positive correlation with CEA levels (P <.02). Patients with obstructive jaundice and elevated CEA levels do not necessarily have cancer. (JAMA 233:326-330, 1975)