Primary liver cancer originates in the liver. The most common form is hepatocellular carcinoma (HCC).([FOOTNOTE=American Cancer Society. Liver Cancer. Updated April 28, 2016. http://www.cancer.org/acs/groups/cid/documents/webcontent/003114-pdf.pdf Accessed December 21, 2016.],[ANCHOR=],[LINK=]) HCC can start as a single tumor in the liver. It then grows and spreads to other parts of the liver. HCC can also start as many small tumors throughout the liver. When HCC is found only in the liver, it’s called “localized.” HCC can spread outside the liver to the lymph nodes or to other organs in the body. If this happens, the cancer has reached a “regional” or “distant” stage.
The most common risk factors for HCC are hepatitis B, hepatitis C, cirrhosis, nonalcoholic fatty liver disease or exposure to aflatoxins. Long-term hepatitis B or C infections are two of the main causes of HCC1.
Secondary (or metastatic) liver cancer originates in another part of the body and spreads to the liver. In most cases, the metastatic liver tumor grows from cells that have spread from cancer in the colon or rectum.
Cancers in the breast, esophagus, stomach, pancreas, lungs, kidney and skin can also spread to the liver.
Secondary liver cancer is more common than primary liver cancer in the United States and Europe1.