Differential Diagnosis of Small HCC Focusing on Pseudolymphoma and Bile Duct Adenoma

Abstract

With the recent advances in diagnostic imaging, an increasing number of hypervascular hepatic nodules such as Hepatocellular Carcinoma (HCC), Cholangiolocellular Carcinoma (CoCC), Bile Duct Adenoma (BDA) and Lymphoproliferative Disorders (LPD) including pseudolymphoma have been detected. We encountered two cases of pseudolymphoma of the liver and two of bile duct adenoma features of which were compared with those of HCC. Imaging studies of pseudolymphoma of the liver in a 57-year-old woman who had Sustained Virological Response (SVR) to Interferon (IFN) treatment of Hepatitis C Virus (HCV), and a bile duct adenoma in a 39-year-old man, who had sustained SVR by treatment of HCV with Pegylated (Peg) IFN plus ribavirin were analyzed through imaging modalities and histochemical studies. Discussed here is the differential diagnosis of HCC in terms of pseudolymphoma and bile duct adenoma and the importance of avoiding overtreatment of benign lesions.

Keywords

Bile Duct Adenoma; Chronic Hepatitis C; Hypervascular Nodule; Pseudolymphoma; Small Hepatocellular Carcinoma

Abbreviation

HCC: Hepatocellular Carcinoma; Cocc: Cholangiolocellular Carcinoma; BDA: Bile Duct Adenoma; LPD: Lymphoproliferative Disorders; FNH: Focal Nodular Hyperplasia; HCV: Hepatitis C Virus; SVR: Sustained Virological Response; Peg INF: Pegylated Interferon; Ig-G: Immunoglobulin G; Ig-A: Immunoglobulin A; Ig-M: Immunoglobulin M; AFP: Alpha-Fetoprotein; CEA: Carcinoembryonic Antigen; CA19-9: Carbohydrate Antigen 19-9; PIVKA II: Protein-Induced By Vitamin K Absence II; CE-US: Contrast Enhanced Ultrasonography; CE-CT: Contrast Enhanced Computed Tomography; CTA: CT During Arteriography; CTAP: CT During Arterial Portgraphy; Gd-EOB-DTPA-MRI: Gadolinium Ethoxybenzyl Diethylenetriamine Pentaacetic Acid Magnetic Resonance Imaging; PCR: Polymerase Chain Reaction