Understanding Focal Liver Lesions: What You Need to Know

Focal liver lesions (FLLs) are abnormal areas of tissue within the liver, often discovered incidentally during imaging tests such as ultrasounds, CT scans, or MRIs. With the increased use of imaging technologies, many people are finding liver lesions, even if they do not have symptoms. Although this can be worrying, most of these lesions are benign (non-cancerous). However, it is important to evaluate these lesions to rule out more serious conditions, like liver cancer. According to the American College of Gastroenterology's 2024 guidelines, developed by experts from renowned institutions like the University of Michigan, Stanford, the University of Virginia, and the University of Chicago, a structured approach is essential for managing these findings.
 

What Are Focal Liver Lesions (FLLs)?
Focal liver lesions (FLLs) refer to abnormal lumps or masses that form in the liver. They are usually found accidentally when doctors are imaging other organs. Common types of benign liver lesions include:

• Hepatocellular adenoma: A rare, non-cancerous tumor associated with hormone use, particularly in women.
• Focal nodular hyperplasia (FNH): A common, harmless mass that seldom causes symptoms.
• Hemangioma: A benign collection of blood vessels, typically not requiring treatment.
• Hepatic cysts: Fluid-filled sacs in the liver that are usually harmless.

 
While most FLLs are benign, some lesions may be malignant (cancerous) or precancerous, including:

• Hepatocellular carcinoma (HCC): The most common type of liver cancer.
• Intrahepatic cholangiocarcinoma (iCCA): Cancer that originates in the bile ducts within the liver.
• Metastatic disease: Cancer that has spread to the liver from other parts of the body.

 
How Are FLLs Detected?
Most FLLs are found during imaging tests done for unrelated reasons, such as investigating abdominal pain or other conditions. Common imaging methods used to detect liver lesions include:

• Ultrasound (US)
• CT scan (computed tomography)
• MRI (magnetic resonance imaging)

 
Once a lesion is discovered, the next steps depend on its appearance and your medical history. If the lesion resembles a benign hemangioma or cyst, further tests may not be necessary.
 

Should You Be Concerned About Incidental Findings?
Incidental liver findings, like benign lesions, usually do not cause symptoms and are not dangerous. However, your doctor may recommend further testing in the following cases:
 

• If you have a history of cancer or liver disease, such as hepatitis or cirrhosis.
• If you experience symptoms like unexplained weight loss, fever, or fatigue.
• If the lesion has an atypical appearance on imaging.

 
In these cases, your doctor may suggest advanced imaging or a biopsy to assess the lesion more thoroughly.
 
Diagnosing and Treating FLLs
In many cases, imaging tests alone can determine whether a liver lesion is benign or malignant. Specialized imaging techniques like contrast-enhanced ultrasounds or MRIs with contrast can provide detailed insights without needing invasive procedures. For example:

• Hemangiomas: Once confirmed via imaging, these lesions generally do not require follow-up unless complications like bleeding are a concern.
• Hepatocellular adenomas: These lesions need to be monitored closely, especially in women, as they can grow and have a small chance of becoming cancerous.
• Focal nodular hyperplasia: FNH is usually harmless and rarely requires treatment, even if it grows in size.

 
When the diagnosis is uncertain, your doctor may recommend a biopsy or regular imaging to monitor the lesion over time.
 

What Tests Might Be Recommended?
If further testing is necessary, your doctor may recommend:

• Liver blood tests: To assess liver function and rule out liver diseases.
• Tumor markers: Blood tests that help detect specific types of cancer.
• Advanced imaging: Techniques such as contrast-enhanced ultrasound (CEUS), multiphase CT scans, or dynamic MRI with contrast can offer more detailed information.

 
In some cases, a liver biopsy may be necessary to collect a tissue sample for more precise diagnosis, especially if imaging alone cannot clearly identify the lesion.
 
Follow-Up and Monitoring
Once a benign liver lesion is confirmed, regular monitoring may not be required. However, your doctor might suggest follow-up imaging if there is uncertainty about the lesion or if you have risk factors for liver cancer. The frequency and type of follow-up tests will depend on the lesion’s characteristics and your overall health.
Sometimes, your case may be reviewed by a multidisciplinary team, including liver specialists, surgeons, and radiologists, to ensure the most appropriate treatment plan.
 

What Happens If the Lesion Is Cancerous?
If a liver lesion is found to be cancerous or is at high risk of becoming cancerous, treatment options may include:

• Surgical removal: Often recommended for large or rapidly growing lesions.
• Liver transplant: May be considered for advanced liver cancer cases.
• Ablation or embolization: These techniques use heat, cold, or chemicals to shrink or destroy tumors.
• Chemotherapy or radiation therapy: These may be used for metastatic liver disease or advanced liver cancer.

 
Conclusion
Although discovering a liver lesion can be concerning, the majority of focal liver lesions are benign and do not require treatment. With accurate imaging and proper monitoring, your healthcare team can guide you through the next steps. If you have been diagnosed with a liver lesion, talk to your doctor about whether additional tests or ongoing monitoring are necessary.
 

Key Takeaways for Patients

• Most liver lesions are harmless: Many people with benign liver lesions live without any issues.
• Imaging is essential: Advanced techniques like contrast-enhanced MRI can diagnose benign lesions without needing a biopsy.
• Explore your options: Discuss with your doctor whether further tests or ongoing monitoring are required.
• Stay informed: Understanding your health is the first step to effectively managing incidental liver findings.

 
At Bumrungrad International Hospital, we provide comprehensive care, including advanced liver imaging and diagnostic techniques, to ensure proper evaluation and treatment of liver lesions.
 

 
Tossapol Kerdsirichairat, MD, FASGE
Clinical Associate Professor of Medicine
Advanced/Bariatric Endoscopy, Digestive Disease Center
Bumrungrad International Hospital