Primary Clear Cell Carcinoma of the Non-cirrhotic Liver Presenting as an Acute Abdomen: a Case Report and Review of the Literature

摘要

Introduction: Hepatocellular carcinoma (HCC) is the sixth most common cancer in the world [1, 2]. The incidence of hepatocellular carcinoma in Northern America in 2008 was 6.8 in males and 2.2 in females [3]. The major risk factors for the development of HCC include alcohol abuse, infection with hepatitis B virus (HBV) or hepatitis C virus (HCV), and non-alcoholic steatohepatitis (NASH) [4]. Other less common causes include autoimmune hepatitis, alpha 1-antitrypsin deficiency, he-mochromatosis, and Wilson's disease [4]. Primary clear cell carcinoma of the liver (PCCCL) is a rare histologic variant of HCC, with frequencies ranging from 0.4 to 37 % [5-8]. The majority of patients with PCCCL are over the age of 50 and have cirrhosis of the liver [7]. The strongest risk factor for PCCCL is HCV infection, with no significant associations with alcohol abuse, HBV infection, NASH, hemochromatosis, or autoimmune liver diseases [7, 9]. PCCCL is characterized by large vacuolated tumor cells with clear cytoplasm that do not stain with hematoxylin and eosin [10, 11]. PCCCL is diagnosed when the proportion these clear cells in the tumor is >50 %, comparing to benign hepatocytes [5-7]. This tumor poses a diagnostic challenge since it has many morphologic similarities to extrahepatic clear cell carcinomas of renal, adrenal, ovarian, pancreas, lungs, and other organs [10, 12]. It is important to distinguish PCCCL from other metastatic clear cell carcinomas as their treatment modalities and prognosis are different [6, 7]. Here, we describe a case of PCCCL, who presented with acute abdomen. The incidence, risk factors, diagnosis, and management of this rare clinical entity are discussed.