There are both benign and malignant neoplasms of the liver.
Cavernous hemangioma is the most common benign liver tumor and usually remains asymptomatic only discovered incidentally on imaging. It appears as a discrete red-blue, soft nodule, usually less than 2 cm in diameter.
Hepatocellular adenoma is a benign neoplasm that typically occurs in young women who take oral contraceptives and anabolic steroids. Multiple hepatocellular adenomas (termed hepatic adenomatosis when 10 or more tumors are present) can occur both in familial and acquired settings. If this adenomas rupture, massive abdominal bleeding occurs and becomes a surgical emergency.
The malignant neoplasms in the liver can be primary or metastatic. The primary epithelial tumors are common with hepatocellular carcinoma and intrahepatic cholangiocarcinoma is the most prevalent. Hepatoblastoma is a rare hepatocellular tumor that occurs in pediatric children. Non-epithelial tumors like angiosarcoma are rare.
The most common early childhood liver cancer is hepatoblastoma and it rarely occurs in children over 3 years of age. These tumors are associated with several syndromes, including familial adenomatous polyposis and Beckwith-Wiedemann syndrome. The clinical manifestations include abdominal swelling in an otherwise asymptomatic child. Symptoms that indicate liver dysfunction like jaundice and pruritus are seen in a subset of patients and about 20% of tumors will have metastasized to the lungs by the time of diagnosis.
One of the most common cancers in geographic regions with high rates of hepatitis B infection is hepatocellular carcinoma and accounts for approximately 5.4% of all cancers worldwide.
Intrahepatic cholangiocarcinoma is referred to the adenocarcinomas arising from the intrahepatic biliary tree while a similar tumor arising from the extrahepatic bile ducts is referred to as biliary adenocarcinoma. This type of cancer is very common in Southeast Asian countries such as Thailand, Laos, and Cambodia, where liver fluke infestation is endemic.
The other primary hepatic malignant tumors that occur are:
- Combined hepatocellular-cholangiocarcinoma
- Epithelioid hemangioendothelioma