Cancer is a process in which cells of an area of the body show uncontrolled and unregulated growth. Liver cancer is any type of cancer facts that occurs in the liver. It can originate in the liver (primary liver cancer) and it can originate in the other tissues of the body and then spread to the liver (secondary).
Primary liver cancers originate in the liver. There are many types of liver cancer. Some of the common types of primary cancers are hepatocellular carcinoma (the most common type), Intrahepatic cholangiocarcinoma (cancer of the bile duct), angiosarcoma, hemangiosarcoma, and hepatoblastoma.
Secondary liver cancers are metastatic types of liver cancer that originate in other tissues of the body and they spread to the liver. Bowel cancer is the most common secondary liver cancer. Cancers in the breast, lung, esophagus, ovary, kidney, pancreas, or stomach can spread to the liver.
Please note that hepatocellular carcinoma is the most common type of primary liver cancer. And liver cancer will be used interchangeably with hepatocellular carcinoma in the remaining sections of this article.
Liver cancer is one of the top ten causes of cancer-related deaths in the United States. In men, it is the fifth most common cause of cancer-related death and in women, it is the seventh most common cause of cancer-related death.
The incidence of liver cancer has been increasing for the last few decades and the death rate has doubled since 1980. It is estimated that 42,230 adults will be diagnosed with primary liver cancer in the US and an estimated 30,230 deaths will occur due to liver cancer.
A risk factor is something that increases the chances of developing a health condition. Some conditions and behaviors may increase the chances of one’s developing primary liver cancer (hepatocellular carcinoma). It is possible to develop liver cancer with few risk factors and alternatively, it is also possible that one may not develop liver cancer even if one has many risk factors for liver cancer.
Gender: Hepatocellular carcinoma is more common in men and it is probably due to behaviors associated with other risk factors for liver cancer.
Alcohol abuse: heaving drinking is the leading cause of liver cirrhosis in the United States and this increases the risk for developing liver cancer.
Smoking: It also increases the chances of developing liver cancer.
Cirrhosis: Cirrhosis is one of the risk factors for developing liver cancer. Cirrhosis is a late stage of fibrosis ( scarring) of the liver. It develops due to progressive damage to the liver over many years. It can be caused due to a variety of diseases.
Hepatitis: Hepatitis B and C also increase the likelihood of developing liver cancer as these infections, if remain undiagnosed and untreated, can cause cirrhosis in the liver. Hepatitis B infection can cause liver cancer without going through a stage of liver cirrhosis.
Fatty liver: Fatty liver also increases the chances of developing liver cancer as it leads to a cirrhotic liver over time. Type 2 diabetes, hypercholesterolemia, high triglyceride levels in the blood, and obesity increase the likelihood of developing fatty liver.
More conditions that are risk factors for developing liver cancer are mentioned below:
- Hemochromatosis (Iron buildup in the body).
- Wilson disease.
- Glycogen storage diseases.
- Alpha-1 antitrypsin deficiency.
- Exposure to aflatoxins.
- Anabolic steroids are used for the long term.
Signs and symptoms
Usually, signs and symptoms of liver cancer do not become apparent until the very late stages of the disease but in some cases, symptoms may arise earlier.
It should be noted that having any or all of the following symptoms does not mean that one has liver cancer. These symptoms can be caused by a variety of health conditions and it is important to consult your healthcare professional for an accurate diagnosis. In some situations, the following symptoms including fluid accumulation in the abdomen, bleeding from the esophagus, and neurological symptoms will be caused by cirrhosis and in these situations, treatment strategies target arresting the progression of cirrhosis and preventing the development of liver cancer.
- Pain in the upper right side of the abdomen or the shoulder region of the same side.- Unexplained weight loss
- A sensation of fullness under the ribs on the right side can be caused by an enlarged liver.
- A sensation of fullness under the ribs on the left side indicating an enlarged spleen.
- Yellowing of the skin or eyes is called jaundice.
- A sensation of fullness after a small meal.
- Decreased appetite.
- Nausea and vomiting.
- Swelling of the abdomen.
Mostly, people are diagnosed with liver cancer after they have experienced some symptoms but sometimes, liver cancer can be detected in an individual through a screening program of high-risk individuals. The doctors usually start with taking a medical history and performing a thorough physical examination and after that, they use many radiological, blood, and biochemical tests to narrow down the conclusive diagnosis or to rule out other possibilities for the presenting symptoms.
History and physical examination:
A doctor will ask detailed questions about one’s medical history to learn about current symptoms and potential risk factors for liver cancer. In the physical examination, the doctor will perform abdominal examination keenly and will also be examining eyes, hands, and skin thoroughly to look for signs of liver disease.
If symptoms and signs are suggestive of liver disease, the doctor will order any blood tests and radiological tests to confirm his tentative diagnosis, to learn about other possible causes of the current symptoms, and to diagnose liver cancer.
Complete blood count: This test is done to measure the levels of different types of blood cells in the blood. It provides an estimate of the functioning of bone marrow.
- Kidney function tests: this test is done to measure creatinine levels and blood urea nitrogen levels to assess different functions of the kidney.
- Liver function tests: These tests are performed to assess the condition of the liver. As liver cancer develops in the liver, the doctor needs to know the condition of the liver before deciding about a treatment plan.
- Clotting tests: as the liver produces the proteins essential for blood clotting, it is possible that these proteins are not produced by a damaged liver and there might be a risk of bleeding. It is helpful to know the clotting status of a patient before starting treatment.
- Tests for hepatitis: The doctor may order some tests to check for viral hepatitis B and C as a potential cause for liver damage.
- Alpha-fetoprotein: It is usually increased in advanced liver disease but other conditions can also cause its elevated levels. This test is performed to diagnose liver cancer, monitor the response of treatment, and estimate the recovery.
Many radiological tests are done to diagnose liver cancer, to study the extent of liver cancer, to monitor treatment response, and to help decide the required treatment. Usually, radiological tests like X-ray, CT scan, MRI, ultrasound, and angiography are performed. In some cases, bone scans may also be performed to look for the spread of cancer to distant tissues like bone.
In most cases, a diagnosis of liver cancer can be established based on radiological tests like CT scan and MRI but in some cases, a biopsy of the tumor may be necessary to reach a definitive diagnosis.
Staging of liver cancer
The process of estimating the spread of cancer is called staging. There are many staging systems for liver cancer. The most commonly used is TNM staging. It estimates the extent of the tumor, it’s spread to nearby lymph nodes and it’s spread to distant sites of the body. This staging system helps to identify the severity and extent of liver damage. For treatment purposes, doctors classify liver cancers into the following types.
- Potentially respectable or transportable cancers.
- Unresectable cancers.
- Inoperable cancer with only local disease.
- Advanced cancers.
It is the best option for treating liver cancer. Different surgical approaches can be used to treat liver cancer. In one type of surgery, a part of the damaged liver is removed. This is called partial hepatectomy. This type of surgery is a suitable option for people whose liver is healthy at least in some areas.
Alternatively, in people who have extensive liver damage and their liver function is negligible, a liver transplant is considered. A liver transplant is a suitable treatment option for people who have small tumors, don’t have spread of cancer beyond the liver or in blood vessels, and in people in which the tumor can not be resected.
This treatment option is considered in people who are not suitable candidates for surgery due to their general poor health or reduced liver function. It is a suitable option for people with small tumors.
In this option, many substances are injected into an artery in the liver to reduce or block the blood flow to a cancerous area. This is a suitable option for people who cannot go through surgery and who have large tumors.
It uses high-energy rays to destroy cancer cells. It is a suitable option for people in whom liver cancer cannot be treated by surgery, ablation, and embolization therapy. It is also used in people with liver cancer who have metastatic liver cancer.
Other treatment options for liver cancer are chemotherapy, immunotherapy, and targeted drug therapy.
The following numbers are merely estimates and they are based on calculations from large studies done on people with similar health conditions.
The 5-year survival rate for localized liver cancer is 34%, for regional liver cancer, it’s 12% and for liver cancer that has spread to distant sites, it is 3%.
Currently, research is being done on many areas relating to liver cancer including improving prevention strategies, detecting cancer early, and improving treatment strategies for liver cancer.
In prevention, many drugs are being tested to treat liver cirrhosis. Also, many drugs are being tested that target limiting the progression of cirrhosis to liver cancer. Many vaccines for hepatitis C are also being tested. As hepatitis is a risk factor for cirrhosis and cirrhosis can progress into liver cancer, preventive research in these areas will have a significant impact on decreasing cases of liver cancer.
To detect cancer, research is being targeted at improving surveillance and screening methods.
To develop more effective treatments, scientists are testing immunotherapy, radiation therapy, and targeted therapy to treat liver cancer.