The Test Sample
What is being tested?
Des-gamma-carboxy prothrombin (DCP) is an abnormal form of prothrombin, a clotting factor produced by the liver. DCP can be produced by liver tumors, and levels are frequently elevated when a person has hepatocellular carcinoma (HCC). This makes the test potentially useful as a tumor marker. This test measures the amount of DCP in the blood.
According to the American Cancer Society (ACS), hepatocellular carcinoma is the most common type of liver cancer, accounting for 3 of 4 cancers that originate in the liver. ACS estimates that about 30,640 new liver cancers will be diagnosed in the U.S in 2013 and about 21,670 people will die of the disease. Liver cancer is much more common in other parts of the world, with more than 700,000 people diagnosed each year.
Most cases of HCC develop in those who have chronic liver diseases such as hepatitis and cirrhosis. In the U.S., the most common risk factor for HCC is a chronic hepatitis C infection; worldwide it is chronic hepatitis B. When it occurs, HCC may emerge several decades after the initial infection. HCC affects more males than females, with the average age of diagnosis at 62 years. Symptoms of HCC, such as a liver mass, abdominal pain, weight loss, nausea, ascites, jaundice, and a worsening of symptoms in those with chronic hepatitis and cirrhosis, are often not present until the later stages of the disease. For this reason, HCC is rarely detected early unless screening is done in those who are at high risk.
It was hoped that DCP testing would prove useful as a screening and surveillance tool to help with early HCC detection in those with chronic liver disease, but studies have shown mixed results and a recent guideline by the American Association for the Study of Liver Diseases (AASLD) recommends that it not be used for this purpose.
How is the sample collected for testing?
A blood sample is obtained by inserting a needle into a vein in the arm.
NOTE: If undergoing medical tests makes you or someone you care for anxious, embarrassed, or even difficult to manage, you might consider reading one or more of the following articles: Coping with Test Pain, Discomfort, and Anxiety, Tips on Blood Testing, Tips to Help Children through Their Medical Tests, and Tips to Help the Elderly through Their Medical Tests.
Another article, Follow That Sample, provides a glimpse at the collection and processing of a blood sample and throat culture.
Is any test preparation needed to ensure the quality of the sample?
No test preparation is needed.