Hepatocellular Carcinoma
Hepatocellular carcinomas (HCC) are also known as primary liver cancers, hepatic tumors, or hepatomas — the four terms are interchangeable.
HCC is a type of cancer that arises from hepatocytes, or specialized epithelial cells in the liver. This makes HCC different from other hepatic cancers in that HCC arises in the liver — it does not spread, or metastasize, to the liver from another part of the body.
HCC affects 4,000 to 6,000 people in the United States each year.
Causes of HCC
Approximately 30 percent of HCC patients treated at UPMC show no evidence of a disease that causes HCC. In other cases, however, HCC often arises after several years of cirrhosis or chronic infection with hepatitis B or C. Other diseases commonly associated with HCC include hemachromatosis and alpha-1-antitrypsin deficiency. Primary biliary cirrhosis; Budd-Chiari syndrome; and metabolic disorders, including porphyria cutanea tarda, citrullinemia, glycogen storage disease, and tyrosinemia, are occasionally associated with HCC.
In some areas of the world, HCC has a strong association with chronic exposure to toxins made by Aspergillus fungi — fungi found in grains and food products, such as peanuts.
In terms of lifestyle choices, heavy and long-term use of alcohol (ethanol) is commonly linked to development of HCC. Radiation therapy and use of cigarettes, oral contraceptives (birth control pills), or anabolic steroids are also associated with HCC.
Detection of HCC
Many people with HCC have no symptoms until the disease becomes advanced. Among the common symptoms of advanced HCC are:
- abdominal (hepatic) pain
- abdominal swelling or mass (a common symptom in children)
- weight loss
- decreased energy
- fevers of unclear origin
- feeling of fullness
- upset or gas-filled stomach
- reduced appetite or aversion to food
- shoulder pain
- general tiredness
- an out-of-sorts mood
- bone pain
Physical signs that a doctor may detect include:
- enlargement of the liver (hepatomegaly)
- harsh or musical sound in the abdomen
- enlargement of the spleen (splenomegaly)
- accumulation of fluid in the abdominal cavity (ascites)
Abnormal Test Results
At least 20 percent of HCC patients at UPMC are diagnosed as a result of abnormalities found in blood tests required for routine physical or health insurance exams. The blood of people with HCC usually shows what doctors call elevated liver function tests.
Other patients — particularly those with a known predisposing disease, such as chronic hepatitis or cirrhosis — are diagnosed because their liver function test results suddenly worsen or because they show abnormal blood test results for alpha-fetoprotein (AFP). (Patients who are known to have chronic hepatitis or cirrhosis usually have an AFP test and an ultrasonogram once or twice a year, as a way of detecting HCC in the early stages.)
Clinicians suspect HCC when they see an opaque mass on an image created by ultrasound or computed tomography. A follow-up biopsy disproves or provides proof of the existence of HCC.
Evaluation of Diagnosed HCC and Surrounding Tissues
In evaluating HCC, computed tomography (CT) scans are important tools. Additional evaluations — such as blood tests and biopsies — help physicians understand the general health status of a patient, the patient’s liver function, and his or her quality of life. If a patient will be treated by chemotherapy, evaluation often includes an audiogram, or hearing test, and a MUGA heart scan.
CT Scans:
After HCC is diagnosed, CT scans help determine:
- the size and location of HCC in the liver
- whether the cancer has spread beyond the liver to form satellite tumors
- the proximity of the tumor to major hepatic blood vessels and if the tumor has invaded the portal vein, the main vein that leads to the liver
- if there are blood clots (thromboses) in any of the major branches of the portal and hepatic veins
- if the lymph nodes are enlarged
A high-speed helical (spiral) triphasic CT scan of the liver allows specialists to evaluate the extent and location of the tumor. A CT scan of the chest and pelvis allow them to determine if the cancer has spread. A bone scan may be performed to exclude or confirm the presence of cancer in bone.
In evaluating CT scans of the tumor, physicians also look for evidence of cirrhosis and its complications, such as ascites, portal hypertension, and splenomegaly (an enlarged spleen).
Blood Tests
Blood tests also help doctors determine the general health status of a patient, including whether he or she has been exposed in the past to hepatitis B or C and if the hepatitis is currently active. In addition, blood test results are a measure of how well the patient’s liver works.
A platelet count is a test that a doctor may order to detect cancer in its early stages. A white cell count that is below the normal range can be a sign of splenomegaly and/or portal hypertension.
Blood tests known as blood chemistries evaluate:
- albumin level
- prothrombin time
- transaminase levels (ALT, AST, GGTP)
- blood creatinine level
Blood tests for specific tumor "markers" include tests that detect the presence of:
- alpha-fetoprotein (AFP)
- desgamma carboxy prothrombin (P, or PIVKA-2)
- neurotensin
Desgamma carboxy prothrombin (DCP) and neurotensin are markers (in the presence of a normal AFP) for the fibrolamellar variant of HCC, which often occurs in children.
Biopsies
In addition to a biopsy of the tumor, radiologists perform a biopsy on a specimen taken from the non-tumorous part of the liver. The liver biopsy helps determine the presence or degree of cirrhosis. A core-needle biopsy, rather than a fine-needle aspiration biopsy, is usually necessary to evaluate the make-up of the tumor.
If the CT scan suggests thrombosis (clotting), then a needle-aspiration biopsy of the portal vein may be necessary. This type of biopsy helps doctors determine if the tumor is actually invading the portal vein. Invasion of the portal vein by a tumor has profound consequences for the long-term outcome of liver transplantation for HCC.