Primary liver cancer is cancer that originates in the liver. Cancer begins when the normal liver cells change and grow uncontrollably. This abnormal growth can be benign (noncancerous) or malignant (cancerous, meaning it can spread to other parts of the body). Secondary liver cancer occurs when cancer spreads (or metastasizes) from another part of the body already affected by cancer and is treated differently, according to the part of the body the cancer originally began. Primary liver cancer is divided into types depending on which liver cell type became cancerous. Hepatocellular carcinoma (HCC) accounts for about 80% of all primary liver cancer cases. Many people, including doctors and researchers, use the term “liver cancer’ to refer to HCC and will call the other subtypes by their specific name. The types and subtypes are listed below.