Overview of cancer 

Cancer is a group of diseases characterised by the uncontrolled growth of abnormal cells. These cells can invade nearby tissues and spread to other body parts, called metastasis. This spread is the leading cause of cancer-related deaths. In 2020, almost 10 million people died from cancer, making it one of the main causes of death around the world. It starts when healthy cells progressively transform into malignant ones through events impacted by an individual's DNA and exposure to toxic substances. Physical elements like radiation, compounds present in asbestos and tobacco smoke, and even illnesses brought on by specific bacteria, viruses, or parasites can all be considered dangerous agents.¹

What is liver cancer?

Liver cancer is a disease where the cells in the liver divide and grow faster than normal, and the cancer starts within the liver itself. The liver is the largest internal organ in the upper abdominal region near the stomach, gallbladder, intestine and the pancreas. The cells of the liver are known as hepatocytes (hi-pat-uh-syt); therefore, liver cancer is also known as hepatic cancer, and hepatocellular carcinoma is the most common type of liver cancer. When the cancer started in another organ, but it has spread to the liver, this is known as secondary liver cancer.² 

What are the causes and risk factors for liver cancer?

Liver cancer results from changes in the DNA structure of liver cells, which can be caused by various factors. 

Risk factors

Chronic viral hepatitis 

Hepatitis B virus (HBV) and hepatitis C virus (HCV) affect the liver cells by chronic inflammation, which induces changes in them, causing hepatocellular carcinoma (HCC). These viral infections can transfer from one individual to another through unprotected sexual habits, sharing of contaminated needles during IV drug use, or in childbirth from mother to the child. These individuals' risk of HCC depends on the viral load.^3,4,5 

Use of alcohol

If you drink a lot of alcohol for a long time, it can harm the liver with an illness called cirrhosis, which in turn, increases the risk of developing liver cancer. The risk of HCC increases by fivefold if an individual consumes greater than 80g of alcohol per day, with most liver cancer cases showing signs of cirrhosis.⁴ 

Use of tobacco

Individuals who have a history of smoking have a lower chance of liver cancer than current smokers. In general, smoking increases the chances of liver cancer.³ 

Aflatoxins 

Aflatoxins are the cancer-causing agents produced by the fungus Aspergillus parasiticus and Aspergillus flavus. They can contaminate grains such as peanuts, soybeans, wheat, rice and corn. These fungi grow in moist and warm environments. Prolonged exposure to these agents can increase the risk of liver cancer. The US and countries in Europe routinely test food to keep aflatoxin levels low and protect public health.^1,4 

Non-Alcoholic Fatty Liver Disease (NAFLD) 

In Non-Alcoholic Fatty Liver Disease (NAFLD), there is a fat storage in the liver, which can cause some symptoms or no symptoms. Nonalcoholic fatty liver (NAFL) and nonalcoholic steatohepatitis (NASH) are types of NAFLD. This fat storage can cause severe damage to the liver, leading to cirrhosis. Additionally, these high levels of fat are risk factors for other diseases like high blood pressure, diabetes, increased triglyceride levels, and obesity, which will elevate the cardiovascular risk.^1,4 

Inherited metabolic conditions 

• Hemochromatosis is an inherited condition in which the body absorbs and stores excessive quantities of iron beyond usual. The absorbed iron can be deposited in various tissues in the body, including the liver. The excess of iron buildup in the liver can lead to cirrhosis and liver cancer⁶
• Tyrosinemia is a rare genetic disorder where the body has trouble breaking down a protein building block called tyrosine⁵
• Acute intermittent porphyria is a rare genetic condition that affects how the body makes a part of the blood called heme (which carries oxygen)^5,6
• Glycogen storage diseases (GSD) are a group of conditions where the body can’t store sugar (glucose) properly for energy⁵
• Wilson disease, which is characterised by the excessive accumulation of copper⁵
• Alpha-1 antitrypsin deficiency, which causes an increase in the probability of developing lung and liver illnesses⁵

Gender 

People assigned as male at birth are more likely to get liver cancer than people assigned as female at birth.⁴ 

Vinyl chloride and thorium dioxide

Exposure to chemicals like vinyl chloride and Thorotrast (thorium dioxide, a radioactive agent used in X-rays) increases the risk of liver cancers, especially angiosarcoma. Once their cancer-causing effects were discovered, Thorotrast was discontinued, and vinyl chloride exposure became strictly regulated.⁷

Use of anabolic steroids 

The prolonged use of anabolic steroids may slightly increase liver cancer risk, while cortisone-like steroids do not have this effect.

Clinical manifestations 

During the initial stages, liver cancer does not show any signs and symptoms, and as the disease progresses, some common symptoms can be seen. These include:⁴ 

• The most common symptom is abdominal discomfort or pain in the upper right area 
• Feeling nauseous
• Vomiting
• Yellowing of skin and sclera of eyes (jaundice)
• Tiredness
• Loss of appetite
• Weight loss
• Bloating (abdominal swelling)
• Increased tendency to bruise or bleed easily
• A firm mass beneath the right rib cage

Prevention strategies

 Some strategies to prevent liver cancer are:^1,4,5

• Maintain a healthy body weight
• Get vaccinated against the hepatitis B virus (HBV)
• Try to reduce the intake of alcohol. If possible, it is better to avoid drinking 
• Do not smoke 
• If you might be at risk, get tested for the hepatitis C virus (HCV)
• Eat a balanced diet: In your diet, you can include fresh vegetables and fruits, lean proteins, and whole grains
• Consume food rich in antioxidants, such as berries, leafy greens. These will help protect the liver
• Avoid exposure to environmental toxins, such as pesticides, arsenic and vinyl chloride
• Get regular health checkups

FAQ’s

Can individuals with hepatitis A and hepatitis E virus develop liver cancer?

No, individuals with hepatitis A and hepatitis E virus will not develop chronic hepatitis or cirrhosis (the liver gets scarred and its functional ability is impaired), and they have no risk of developing liver cancer.

Does heavy body weight cause liver cancer?

Heavy body weight is a risk factor that can make you more likely to get liver cancer.

When to see a doctor?

If you notice the above-mentioned symptoms over a while, you can visit your physician to rule out the exact disease condition.

What are the types of liver cancer?

Liver cancer is mainly of two kinds, primary liver cancer and secondary liver cancer. Primary liver cancer develops in the liver. The common type of primary liver cancer is hepatocellular carcinoma. 

What tests are done to detect liver cancer?

The tests done to detect liver cancer include CT scan, MRI scan, lab tests and liver biopsy. 

Summary

• Early diagnosis and prevention of liver cancer will reduce the risk of mortality
• Encourage the individuals to get tested and vaccinated against hepatitis
• By providing education to patients and their caregivers, we can reduce the incidence of liver cancer