Clinical Characteristics of Patients with Cryptogenic Hepatocellular Carcinoma in a Hepatitis B Virus-Endemic Area

Abstract

Objectives: Chronic hepatitis B virus (HBV) infection is the most common cause of hepatocellular carcinoma (HCC) in South Korea, but a high prevalence of metabolic diseases may result in increases in the incidence of cryptogenic HCC (cHCC). We studied characteristics of the cHCC in a single-center cohort. Methods: A cohort of 1,784 HCC patients newly diagnosed and treated at the National Cancer Center, Korea, between 2004 and 2009 was reviewed and analyzed. Results: The cause of HCC was categorized as cHCC, HBV, hepatitis C virus (HCV), or alcohol. Overall, 162 (9.1%) patients of the HCC cohort had cHCC, and their mean age was 61.9 years. The median survival of cHCC patients was 24.7 months, which was the second shortest among the four groups after HBV HCC. cHCC patients had the largest tumor size (mean 7.4 cm) and the second highest proportion of poor prognostic factors such as the proportion of poorly defined tumors and extrahepatic spread in imaging studies. cHCC patients had better survival than HBV HCC patients according to multivariate analysis. Among cHCC patients, 137 (84.6%) had anti-HBc IgG antibodies, but this sub-group had different clinical features to those of HBV HCC patients. The body mass index (BMI) and hyperglycemia and hypercholesterolemia levels in cHCC patients were similar to those in HCV and alcoholic HCC patients. Conclusions: Anti-HBc IgG antibodies were present in most cHCC patients, but cHCC patients had better survival than HBV HCC patients on multivariate analysis. However, cHCC patients had a larger mean tumor size and more aggressive tumor characteristics than HCV HCC or alcoholic HCC patients did. It is hoped that this study will contribute to a better understanding of cHCC in HBV-endemic areas.