Hepatocellular Carcinoma (HCC)

Overview
  • Hepatocellular Carcinoma (HCC), whose cell of origin is the hepatocyte, is the most common primary malignant neoplasm of the liver.
Incidence
  • Overview
    • HCC almost always arises within a background of chronic liver disease. The rates and patterns of incidence differ between developing and developed countries. This is not an exhaustive list of etiologies but rather the primary culprits in different populations.
  • Developing Countries
    • Incidence can be up to ten times higher than in developed countries, correlating with higher Hepatitis B Virus infection rates. The greatest risk factor is chronic infection with HBV acquired vertically from the mother. In many cases, HCC can arise in an HBV-carrier in the absence of cirrhosis.
  • Developed Countries
Pathogenesis
  • The pathogenesis of HCC is not well-understood except in the cases where it is initiated by carcinogenic "Aflatoxins" derived from the Aspergillus. For the vast majority of cases, which are secondary to chronic liver diseases, it is thought that the etiologic agents of the chronic liver disease are not in themselves highly carcinogenic. Rather, it is thought that continuous damage to hepatocytes from these chronic liver diseases results in repeated rounds of regenerative hepatocyte replication, yielding accumulated mutations that ultimately result in neoplasia.
Morphology
  • HCCs can grow in a variety of architectures including a single large tumor, multiple smaller nodules, or diffusely throughout the hepatic parenchyma. Whatever the overall architecture, neoplastic cells invade and spread through blood vessels relatively easily and can grow into the portal vein and even into the inferior vena cava as a solid tube of cells. Histologically, neoplastic cells can range from well-differentiated cells resembling hepatocytes to those displaying significant anaplasia.
Clinical Consequences
  • The clinical consequences of HCC are usually encountered within the background of underlying chronic liver disease. hepatomegaly, abdominal pain, weight loss, ascites, and fever may be presenting symptoms. The presence of jaundice is usually due to the underlying chronic liver disease. Budd-Chiarri Syndrome is a frequent complication when HCC invades the portal vein. Hemorrhage of the neoplasm into the peritoneum leading to hemoperitoneum can be fatal. Sadly, prognosis for HCC is extremely poor and the survival rate is on the order of months following diagnosis.
Labs
  • Alpha-fetoprotein (AFP) levels are elevated in patients with HCC but this is an extremely unspecific laboratory result as many other conditions share this pattern of elevation including other chronic liver diseases.