Liver Cancer: Understanding Risk Factors, Prevention, and Treatment

20 May,2024

Liver cancer is becoming increasingly common, with over 900,000 cases recorded worldwide each year. It is more prevalent in regions like Sub-Saharan Africa and Southeast Asia. Late-stage liver cancer is difficult to treat and often results in death. Hence, early detection is crucial for successful treatment. If you or anyone you know has been diagnosed with liver cancer, making an informed decision quickly is essential to ensure better outcomes. This blog aims to provide detailed information regarding the various risk factors of liver cancer and the various prevention and treatment options available.

What is Liver Cancer?

The liver is a crucial body organ responsible for several vital functions, such as digestion, bile production, nutrient storage, blood filtering, medication metabolism, and more.

Liver cancer occurs when liver cells experience uncontrolled growth. If the cancer originates in the liver, it is called primary liver cancer. In contrast, if the cancer comes from another part of the body and spreads to the liver, it is called secondary liver cancer.

There are three primary types of liver cancer, which include:

• Hepatocellular Carcinoma (HCC): It is the most common type of primary liver cancer that accounts for ~80% of cases.
• Intrahepatic Cholangiocarcinoma (IHC): Also known as bile duct cancer, it accounts for 10% to 20% of primary liver cancer cases.
• Angiosarcoma: It is the rarest type of liver cancer and accounts for only 1% of cases.

HCC and IHC are more common in men than women, and people between the ages of 55 and 64 are most often diagnosed with these types of liver cancer. Furthermore, people whose race includes Asian/Pacific Islander, Hispanic, or American Indian/Alaskan Indian are more susceptible to developing primary liver cancer than those who are Black or white.

What are the Signs of Liver Cancer?

Liver cancer symptoms can be pretty vague, making it difficult to diagnose in the early stages. Therefore, awareness of the risk factors and what signs to look for is necessary. 

Here are some of the signs and symptoms of liver cancer. If you are experiencing any of these symptoms, it does not necessarily mean that you have liver cancer. However, it is always advisable to consult the best oncologists and get regular health check-ups. The symptoms of liver cancer include:

• Unintentional weight loss
• Nausea and vomiting
• Loss of appetite
• Dark-colored urine
• Enlarged liver or spleen
• Jaundice
• Swelling and pain in the abdomen
• Hypercalcemia
• Hypoglycemia
• High cholesterol levels

Are There Any Risk Factors for Liver Cancer?

Liver cancer is identified as the third leading cause of cancer-associated deaths worldwide. While diseases can affect any individual, researchers have identified certain risk factors for them. These include –

• Hepatitis B Virus Infection: Infection with hepatitis B virus (HBV) causes severe inflammation of the liver, which can lead to cancer. Hepatitis B can spread through body fluids such as blood and semen. Chronic HBV infection is the chief cause of liver cancer in Asians and Africans.
• Hepatitis C Virus Infection: Infection with hepatitis C virus (HCV) causes liver cirrhosis. Like HBV, HCV also spreads through body fluids. Sharing needles and unprotected sex can lead to HCV infection. Chronic HCV infections are one of the main causes of cancer in Europeans, Japanese, and North Americans.
• Cirrhosis: Cirrhosis is the scarring of healthy liver tissue. It occurs due to heavy alcohol consumption and hepatitis infection. The blood flow through the liver gets blocked, which can lead to liver cancer.
• Alcohol Consumption: Alcohol consumption is associated with liver cirrhosis. Although heavy alcohol can alone cause liver cancer, the risk increases ten times if the person also has cirrhosis. The risk increases if the person is infected with hepatitis. 
• Cigarette Smoking: Cigarettes are another risk factor for liver cancer. The number of cigarettes one smokes and for how long they have been smoking is directly proportional to the risks. 
• Aflatoxin B1: Certain fungi release toxins known as aflatoxin B1. Eating food that contains Aflatoxin B1 increases the chances of developing liver cancer. People living in Africa, Asia, and China are the most affected. 
• Nonalcoholic Steatohepatitis (NASH): Nonalcoholic steatohepatitis is one of the most serious forms of nonalcoholic fatty liver. It is marked by the deposit of fats in the liver. NASH causes liver cell inflammation and can lead to cancer.

How is Liver Cancer Diagnosed?

Hepatocellular carcinoma or liver cancer can be diagnosed in several ways. If the doctor suspects liver cancer during a physical examination, they may further order diagnostic tests such as –

• Blood Test: Tests like liver function tests (LFT) help identify whether the organ is healthy or damaged. LFT checks the amount of proteins, enzymes, and other substances in the liver. High levels of alfa-fetoprotein (AFP) may indicate cancer.
• Ultrasound: Liver ultrasound creates images of the liver using sound waves. People who are at an increased risk of developing liver cancer or have high scarring of the liver are advised to have an ultrasound every six months. 
• CT Scan: A computed tomography or CT scan is a specialized form of X-ray that makes clear and crisp images of the liver. It helps in detecting the size and location of liver tumors.
• MRI Scan: Magnetic resonance imaging uses radio and magnetic waves to make pictures of the liver and surrounding tissue. Like a CT scan, it also helps understand the size and location of the tumor. 
• Liver Biopsy: A biopsy is the most reliable way to determine whether liver cells are cancerous. It also helps oncologists understand the type of liver cancer.
• Endoscopic Retrograde Cholangiopancreatography (ERCP): Bile duct cancer can be diagnosed with ERCP. The procedure involves using a catheter and an endoscope to examine bile ducts.

How Can You Prevent Liver Cancer? 

You cannot prevent liver cancer entirely. However, knowing the risk factors and following a few steps can reduce your chances of developing the disease. Preventive measures for liver cancer are –

• Alcohol Abstinence: Staying away from alcohol reduces the chances of liver cirrhosis to a great extent. By lowering the risk of cirrhosis, the chances of developing liver cancer are also reduced. If you can't altogether avoid alcohol, at least try to drink in moderation. 
• Maintain a Healthy Weight: An optimal body weight is necessary to prevent liver cancer and other diseases. If you are obese, try losing half a kg weekly by having a healthy diet and exercising most days.
• Vaccination for Hepatitis B: A vaccine can easily prevent hepatitis B. Vaccines can be given to infants and adults at any point in life. They prevent chronic liver infection, a potential risk factor for liver cancer.
• Prevent Hepatitis C: While there is no vaccine for hepatitis C, the infection can be prevented by following measures such as not sharing needles, having protected sex, getting tattoos/piercings from safe and clean shops, etc. Lowering the chances of hepatitis c infection reduces the chances of liver cancer.
• Get Regularly Screened: Liver cancer screening is not recommended for the general population. However, doctors suggest people with conditions such as hepatitis B and C infection, obesity, diabetes, and liver cirrhosis should get regularly screened for liver cancer.

How is Liver Cancer Treated?

Treatment for liver cancer is decided based on stage and type of cancer. Oncologists can use a combination of treatment options for managing liver cancer. Following are the multiple treatment modalities available to treat primary liver cancer. 

Surgery

Surgery involves removing a tumor along with some healthy tissue surrounding it. It is a highly effective treatment for liver cancer, particularly for patients with good liver function and tumors that surgeons can safely remove from a limited part of the liver. However, patients may not be eligible for surgery if the cancer has spread outside of the liver, their liver is too damaged, or if they have other serious illnesses.

There are two types of surgery used to treat liver cancer:

• Hepatectomy: This surgery removes a portion of the diseased liver. It can only be performed if the cancer is present in one part of the liver and the liver is functioning well. The remaining section of the liver performs all the functions of the entire liver. After a hepatectomy, the liver may grow back to its standard size within a few weeks. However, patients with advanced cirrhosis may not be able to undergo a hepatectomy, even if the tumor is small.
• Liver Transplant: This surgery involves removing the patient's liver and replacing it with a healthy one from a donor. A liver transplant is only possible when specific criteria are met, including having a certain tumor size and number of tumors and finding a suitable donor.

Embolization Therapy

Embolization therapy treats liver tumors by blocking or reducing the flow of blood through the hepatic artery to the tumor. This procedure restricts the oxygen and nutrients the cancer needs to survive, causing it to stop growing. The therapy is typically used for individuals who cannot undergo surgery or ablation therapy and whose tumors have not spread outside the liver.

Two main types of embolization therapy are transarterial embolization (TAE) and transarterial chemoembolization (TACE). 

• In transarterial embolization (TAE), a catheter is inserted into the hepatic artery through a small incision in the inner thigh. Once the catheter is in place, a substance is injected that blocks the hepatic artery and stops blood flow to the tumor. 
• In transarterial chemoembolization (TACE), an anticancer drug is added to the procedure. The drug can be injected into the hepatic artery through the catheter or attached to tiny beads that are injected into the artery. This treatment is also called chemoembolization. Most of the chemotherapeutic drug is trapped near the tumor, so only a tiny amount of the drug reaches other parts of the body.

Ablation Therapy

Ablation therapy is a type of treatment that can remove or destroy tissue. In the case of liver cancer, different types of ablation therapies can be used. These include:

• Radiofrequency Ablation: This involves using special needles inserted directly into the tumor through the skin or an incision in the abdomen. High-energy radio waves are then used to heat the needles and tumors, killing cancer cells.
• Heat Therapy: In this treatment, the tumor is exposed to high temperatures created by microwaves. This can damage and kill cancer cells. It can also make them more susceptible to the effects of radiation and certain chemodrugs.
• Percutaneous Alcohol Injection: This involves using a small needle to inject pure alcohol (ethanol) directly into the tumor to kill cancer cells. Patients may require several treatment sessions. Local anesthesia is usually used, but if the patient has multiple tumors in the liver, general anesthesia may be used.
• Cryoablation: This treatment involves using an instrument to freeze and destroy cancer cells. It may also be referred to as cryotherapy or cryosurgery. The oncologist may use ultrasound to guide the freezing instrument.
• Electroporation Therapy: This treatment involves sending electrical pulses through an electrode placed in the tumor to kill cancer cells

Radiation Therapy

To make radiation more effective, radiation oncologists administer radiation therapy in a series of treatments that allow healthy cells to recover. The number of treatments they prescribe depends on the cancer's specific details, including the tumor's size and location. To prevent radiation from damaging nearby healthy tissue, healthcare professionals employ specific methods of giving external radiation therapy, including:

• Stereotactic Body Radiation Therapy: The oncologist uses special equipment to place the patient in the same position for each radiation session. Once a day for several days, a radiation machine aims a larger-than-usual dose of radiation directly at the tumor. Since the person lies in the same position for each treatment, damage to nearby healthy tissue is minimal.
• Proton Beam Radiation Therapy: This type of high-energy, external radiation therapy uses protons (tiny particles) to destroy tumor cells. The medical team uses this type of treatment to lower the amount of radiation damage to healthy tissue near a tumor.
• Conformal Radiation Therapy: It involves using a computer to create a 3-dimensional image of the tumor and shape the radiation beams according to the tumor. This method delivers a high radiation dose to the tumor causing less damage to the sorrounding healthy tissue.

Immunotherapy

Immunotherapy is a biological cancer treatment that enhances the immune system's ability to disrupt cancer cells. It uses the body's natural defenses to fight against cancer. 

• One of the most common immunotherapy types is an immune checkpoint inhibitor.
• This treatment works by preventing tumor cells from hiding from the immune system, which would otherwise allow them to grow and spread throughout the body.
• There are several drugs currently available for immunotherapy, including nivolumab, pembrolizumab, nivolumab with ipilimumab, atezolizumab with bevacizumab, tremelimumab, and durvalumab.
• However, immunotherapy can have side effects, such as flu-like symptoms, diarrhea, skin reactions, and weight changes.

Targeted Therapy

Targeted therapy is an effective cancer treatment that specifically targets cancer cells and limits the damage to healthy cells. This type of treatment aims to block cancer cell's growth and spread.

• Anti-angiogenesis drugs are amongst the most common types of targeted therapy for people with liver cancer. 
• Anti-angiogenesis therapy works by stopping angiogenesis, which is the creation of new blood vessels.
• This therapy aims to starve the tumor by depriving it of the nutrients delivered by blood vessels.
• Common anti-angiogenesis drugs are bevacizumab with atezolizumab, cabozantinib, lenvatinib, regorafenib, and sorafenib.
• Targeted therapy may have side effects. These include high blood pressure, back pain, headaches, changes in taste, fatigue, diarrhea, appetite loss, and joint and muscle pain.

Palliative Care

Palliative care is a specialized form of oncology care focusing on alleviating pain and other symptoms associated with severe illnesses. 

• Palliative care specialists work with your family and other doctors to offer additional support that complements your ongoing treatment. 
• Oncologists use palliative care in conjunction with other aggressive treatments like chemotherapy, radiation therapy, and surgery.
• When palliative care is combined with other appropriate treatments, people with liver cancer can feel better and even live longer. 
• With palliative care, cancer patients observe significant improvement in their quality of life.

Key Takeaway

Liver cancer is a serious medical condition, but early detection and treatment can improve the probability of a successful outcome. You can take charge of your liver health by understanding the risk factors, taking preventive measures, and getting regular checkups. If you or someone you know has been diagnosed with liver cancer, remember that there are many treatment options available. Working with a team of oncologists, you can make a treatment plan that addresses your specific needs.