Liver cancer

Liver cancer, also known as hepatic cancer and primary hepatic cancer, is cancer that starts in the liver. Cancer which has spread from elsewhere to the liver, known as liver metastasis, is more common than that which starts in the liver. Symptoms of liver cancer may include a lump or pain in the right side below the rib cage, swelling of the abdomen, yellowish skin, easy bruising, weight loss and weakness. Liver cancer, also known as hepatic cancer and primary hepatic cancer, is cancer that starts in the liver. Cancer which has spread from elsewhere to the liver, known as liver metastasis, is more common than that which starts in the liver. Symptoms of liver cancer may include a lump or pain in the right side below the rib cage, swelling of the abdomen, yellowish skin, easy bruising, weight loss and weakness. The leading cause of liver cancer is cirrhosis due to hepatitis B, hepatitis C or alcohol. Other causes include aflatoxin, non-alcoholic fatty liver disease and liver flukes. The most common types are hepatocellular carcinoma (HCC), which makes up 80% of cases, and cholangiocarcinoma. Less common types include mucinous cystic neoplasm and intraductal papillary biliary neoplasm. The diagnosis may be supported by blood tests and medical imaging, with confirmation by tissue biopsy. Preventive efforts include immunization against hepatitis B and treating those infected with hepatitis B or C. Screening is recommended in those with chronic liver disease. Treatment options may include surgery, targeted therapy and radiation therapy. In certain cases, ablation therapy, embolization therapy or liver transplantation may be used. Small lumps in the liver may be closely followed. Primary liver cancer is globally the sixth-most frequent cancer (6%) and the second-leading cause of death from cancer (9%). In 2012, it occurred in 782,000 people, and in 2015 it resulted in 810,500 deaths. In 2015, 263,000 deaths from liver cancer were due to hepatitis B, 245,000 to alcohol and 167,000 to hepatitis C. Higher rates of liver cancer occur where hepatitis B and C are common, including Asia and sub-Saharan Africa. Males are more often affected with HCC than females. Diagnosis is most frequent among those 55 to 65 years old. Five-year survival rates are 18% in the United States. The word 'hepatic' is from the Greek hêpar, meaning 'liver'. Because liver cancer is an umbrella term for many types of cancer, the signs and symptoms depend on what type of cancer is present. Cholangiocarcinoma is associated with sweating, jaundice, abdominal pain, weight loss and liver enlargement. Hepatocellular carcinoma is associated with abdominal mass, abdominal pain, emesis, anemia, back pain, jaundice, itching, weight loss and fever. Viral infection with either hepatitis C virus (HCV) or Hepatitis B virus (HBV) is the chief cause of liver cancer in the world today, accounting for 80% of hepatocellular carcinoma (HCC). The viruses cause HCC because massive inflammation, fibrosis, and eventual cirrhosis occurs within the liver. HCC usually arises after cirrhosis, with an annual incidence of 1.7% in cirrhotic HCV-infected individuals. Around 5-10% of individuals that become infected with HBV become chronic carriers, and around 30% of these acquire chronic liver disease, which can lead to HCC. HBV infection is also linked to cholangiocarcinoma. The role of viruses other than HCV or HBV in liver cancer is much less clear, even though there is some evidence that co-infection of HBV and hepatitis D virus may increase the risk for HCC. Many genetic and epigenetic changes are formed in liver cells during HCV and HBV infection, which is a major factor in the production of the liver tumors. The viruses induce malignant changes in cells by altering gene methylation, affecting gene expression, and promoting or repressing cellular signal transduction pathways. By doing this, the viruses can prevent cells from undergoing a programmed form of cell death (apoptosis) and promote viral replication and persistence. HBV and HCV also induce malignant changes by causing DNA damage and genomic instability. This is by creating reactive oxygen species, express proteins that interfere with DNA repair enzymes, and HCV causes activation of a mutator enzyme. In addition to virus-related cirrhosis described above, other causes of cirrhosis can lead to HCC. Alcohol intake correlates with risk of HCC, and the risk is far greater in individuals with an alcohol-induced cirrhotic liver. There are a few disorders that are known to cause cirrhosis and lead to cancer, including hereditary hemochromatosis and primary biliary cirrhosis.