5- Liver

Tumors of the Liver

Primary Hepatic Neoplasms

  • Prevalence: Primary hepatic neoplasms are significantly less common than metastatic tumors.

  • Types: The majority of primary hepatic malignancies are hepatocellular carcinomas (HCC) and cholangiocarcinoma. Less common forms include:

    • Hepatoblastoma: A childhood hepatocellular tumor.

    • Angiosarcoma: A rare type of cancer originating from blood vessels.

Benign Tumors

  1. Hemangiomas

    • Description: These are the most common benign lesions of the liver, featuring well-circumscribed lesions made up of vascular channels lined by endothelial cells.

    • Appearance: Typically appear as discrete red-blue lesions, less than 2 cm in diameter.

    • Clinical Importance: Important to differentiate from metastatic tumors due to potential for misdiagnosis. Blind percutaneous needle biopsies may cause severe intra-abdominal bleeding.

  2. Von Meyenburg Complexes

    • Description: Common benign findings characterized by disorganized bile ducts surrounded by densely fibrotic stroma.

  3. Focal Nodular Hyperplasia (FNH)

    • Description: A well-demarcated lesion consisting of hyperplastic hepatocyte nodules with a central fibrous scar.

    • Demographics: Frequently seen in women of reproductive age.

  4. Hepatic Adenoma

    • Description: Typically occurs in young women who use oral contraceptives. Lesions are usually well-demarcated and can grow up to 30 cm in diameter.

    • Clinical Relevance: Potential to regress upon cessation of hormone use. Can be mistaken for hepatocellular carcinoma. There is a risk of rupture, especially during pregnancy, leading to life-threatening intra-abdominal hemorrhage.

Hepatocellular Carcinoma (HCC)

  • General Information: Also known incorrectly as hepatoma. Incidence varies globally, with over 85% of cases occurring in regions with high chronic HBV infection rates and aflatoxin exposure.

  • Etiology: Major associations include:

    1. Infection with HBV or HCV.

    2. Alcoholic cirrhosis.

    3. Aflatoxin exposure.

  • Other Risk Factors: In the United States, non-alcoholic fatty liver disease (NAFLD) is a significant concern, along with conditions such as hemochromatosis and α1-antitrypsin deficiency.

  • Tumor Presentation: May be unifocal or multifocal, with nodules of varying sizes. Histologically, HCC can be well-differentiated to poorly differentiated.

  • Special Variant:

    • Fibrolamellar Carcinoma: Occurs in young adults and is not typically associated with cirrhosis or common risk factors. It has a better prognosis compared to typical HCC.

  • Symptoms: Can present with silent hepatomegaly, often identified in patients with symptomatic liver cirrhosis.

  • Diagnosis: Serum alpha-fetoprotein levels are commonly used as a marker, though they may only be elevated in advanced tumors and in 50% of patients.