Hepatocellular Carcinoma

Abstract

Hepatocellular carcinoma (HCC) is a heterogeneous tumor that is often but not invariably associated with cirrhosis. The tumor can be well, moderately, or poorly differentiated. At the highly well-differentiated end, the tumor has to be distinguished from other well-differentiated hepatocellular nodular lesions, and hence a diagnosis of malignancy may be challenging to establish. At the poorly differentiated end, the malignant status is obvious, but the cell origin of cancer may be unclear. There are 2 main diagnostic challenges, namely, (i) either cirrhotic or noncirrhotic liver gives rise to a range of well-differentiated hepatocellular nodular lesions from which HCC has to be distinguished for therapeutic and prognostic purposes, and (ii) the liver is a common depository for metastases, which may mimic HCC and its variants. Hepatocellular carcinoma has a spectrum of clinical manifestations. A history of chronic viral hepatitis B or C or chronic alcoholism is common. Serum α-fetoprotein is often not significantly elevated. Tumors with classic contrast-enhanced imaging features such as arterial enhancement with portal and delayed venous washout are often not subjected to preoperative tissue confirmation by fine-needle aspiration biopsy or core-needle biopsy because of risk of bleeding and needle-tract seeding. Small tissue samples of cytohistologic material pose different types of diagnostic challenges. Ancillary tests such as immunohistochemistry may be helpful.A 70-year-old Chinese man has chronic hepatitis B virus (HBV) infection and a history of resection for colonic adenocarcinoma. A radiologically diagnosed 1.8-cm-diameter liver metastasis responded to adjuvant chemotherapy. Serum α-fetoprotein (AFP) and carcinoembryonic antigen (CEA) were not elevated. Ultrasound surveillance 2 years later showed 3 lesions in the liver suggestive of being cirrhotic. Magnetic resonance imaging revealed fatty change in the largest nodule. The differential diagnosis was among hepatocellular carcinoma (HCC), hepatocellular adenoma (HCA) with fatty change, and angiomyolipoma (AML) (Fig. 1). The smaller lesions were considered dysplastic nodules. Ultrasoundguided fine-needle aspiration biopsy (FNAB) and core-needle biopsy (CNB) were performed on the largest nodule, followed eventually by segmentectomy.