Liver cancer refers to cancer cells found in the liver. The cancer cells can either arise in the liver (primary cancer) or are spread from other cancer sites to the liver (secondary cancer). It is one of the most common forms of cancer in the world. The type of liver cancer depends on the type of cells which become cancerous.
For most cases, the exact causes are not clear. However, in some cases, the cause is known, e.g. chronic infection with certain hepatitis viruses can cause liver cancer.