Peripheral intrahepatic cholangiocarcinoma: ultrasound findings and differential diagnosis from hepatocellular carcinoma

Abstract

Objective: Peripheral cholangiocarcinoma may be more frequent than expected, and is usually asymptomatic until it is well advanced. Our purpose was to assess the accuracy of ultrasound in differential diagnosis. Methods: We compared the sonographic findings of ten consecutive patients with histologically proven peripheral cholangiocarcinoma with those obtained in 26 consecutive patients with hepatocarcinoma detected in the same period. In every patient we performed an ultrasound-guided biopsy with a fine (22 gauge) cutting needle. Results: In all patients with a final diagnosis of peripheral cholangiocarcinoma, the ultrasound scan disclosed multiple well-defined nodules with a hypoechoic or target pattern. Two patients had dilated intrahepatic bile ducts and suspected infiltration of the common duct. No patient had ascites. Only minimal alterations in laboratory examinations were found. Ultrasound-guided fine cutting needle biopsy yielded diagnostic material and allowed the definitive differential diagnosis. Conclusion: Peripheral cholangiocarcinoma even in Western countries may represent a significant proportion of all primary liver cancers. Due to non-specific symptomatology only intractable and far advanced cases were detected by means of sonography. Ultrasound findings did not differ from those found in cases of metastases from extrahepatic adenocarcinomas or hepatocarcinoma with multinodular pattern (10/26 in our series).