Liver cancer is a type of cancer that develops in the inner layer of the liver and the liver tissues. Liver cancer is also known as hepatic cancer and sometimes as primary hepatic cancer. When cancer starts elsewhere in the body and metastasizes to the liver, it is called secondary liver cancer. Primary liver cancers are quite rare. Secondary liver cancer accounts for more than 90 percent of all tumors in the liver.

One of the main functions of the liver is to filter out toxins from the blood. So, if cancerous cells are spreading through the body, it is sure to be deposited in the liver, and in this way, cancer spreads to the liver.

Types of liver cancer
Several types of liver cancer occur in the body, depending on the cells in which it begins.

• Hepatocellular carcinoma
• Intrahepatic cholangiocarcinomas
• Hemangiosarcomas and angiosarcomas
• Hepatoblastoma
• Benign liver tumors

Risk factors 
The most common risk factor for liver cancer is an infection of the liver with both hepatitis B and C virus. These viral infections are chronic. Chronic inflammation for many years may lead to changes in the liver cells, and these changes may lead to cancer. The two viruses (Hepatitis B and C) can spread when a person comes into contact with body fluids of people infected with these viruses. Contaminated needles and unprotected sex are the most common ways in which people contract ths infection. By avoiding high-risk behavior, one can reduce the risk of this condition. Vaccines for hepatitis B can help people avoid this condition and also lead to a reduction in the risk of liver cancer.

Symptoms 
The symptoms of liver cancer are mostly indistinct and unclear because of which they may go unnoticed. These symptoms may also similar to those caused by other health conditions. Loss of appetite, weight loss, fever, weakness, fatigue, swollen abdomen, pain in the abdomen, nausea, dark urine, and yellowing of the skin are some of the symptoms of liver cancer.

Stages 
When a person is diagnosed with liver cancer, they may need to undergo several other tests to find out if the cancerous cells have spread to other parts of the body. The stages of liver cancer depend on the extent of its spread to other parts of the body.

• Stage-1 liver cancer: In this stage of cancer, the tumor is confined to the liver and has not grown into the blood vessels.
• Stage-2 liver cancer: The tumor has grown in size and may have grown into the blood vessels. It has not spread to the lymph nodes situated nearby or other parts of the body.
• Stage-3 liver cancer: By this stage, several tumors have developed in the liver, or the tumor has grown into a nearby organ. But, cancer has still not spread to the lymph nodes or distant organs of the body.
• Stage-4 liver cancer: In the fourth stage, liver cancer spreads to the lymph nodes or other blood vessels and organs situated nearby.
• Recurrent liver cancer: A person is said to have this form of cancer when they develop this condition again after undergoing treatment.