The liver, located in the upper right abdomen, plays a central role in numerous bodily functions, including detoxification, protein synthesis, and bile production. A “mass on the liver” refers to any abnormal growth or lesion within this organ. While finding a mass can be concerning, not all liver masses indicate a serious condition.
Understanding Liver Masses
A liver mass describes an abnormal formation of tissue within the liver, which can be solid, fluid-filled (cystic), or a combination. Many are discovered incidentally during imaging for unrelated health concerns.
Liver masses fall into two main categories: non-cancerous (benign) or cancerous (malignant). Benign masses are confined to the liver and do not spread. Malignant masses can invade surrounding tissues and spread to distant organs, a process known as metastasis.
Common Non-Cancerous Liver Masses
Many liver masses identified are benign, meaning they are not cancerous and often do not require aggressive intervention.
Hemangiomas
These are among the most frequently encountered benign liver masses, appearing as tangles of abnormal blood vessels. These vascular lesions are often present from birth and usually remain small, causing no symptoms. Most hemangiomas are discovered incidentally and typically do not require treatment unless they grow very large or cause discomfort, which is rare.
Focal Nodular Hyperplasia (FNH)
FNH represents another common benign liver lesion, characterized by a central scar surrounded by abnormal liver cells. These formations are believed to result from an unusual response of liver cells to an abnormal blood supply. FNH lesions are typically asymptomatic and are often found during imaging studies performed for other reasons, generally not requiring treatment.
Liver Cysts
These fluid-filled sacs that can develop within the liver, ranging from simple, congenital cysts to more complex ones. Simple liver cysts are often present from birth and are usually harmless, posing no health risks. Unless they grow large enough to cause symptoms like pain or pressure, most liver cysts do not require any medical intervention or monitoring.
Hepatic Adenomas
Rarer benign tumors, hepatic adenomas originate from liver cells and are more commonly observed in women, particularly those using oral contraceptives. These masses can sometimes grow significantly, potentially leading to symptoms like abdominal pain or, in rare instances, bleeding. There is also a small, though recognized, risk that adenomas could transform into a malignant tumor, prompting careful consideration for their management.
Cancerous Liver Masses
When a liver mass is cancerous, it can either originate within the liver tissue itself or spread to the liver from a cancer elsewhere in the body. Differentiating between these types is crucial for determining the appropriate course of treatment.
Primary Liver Cancer
This cancer begins in the liver, most commonly as hepatocellular carcinoma (HCC). This aggressive form of cancer frequently develops in individuals with chronic liver diseases, such as those caused by long-term hepatitis B or C infections, or cirrhosis resulting from excessive alcohol consumption. The presence of significant liver scarring from these conditions increases the risk of HCC development.
Metastatic Liver Cancer
This occurs when cancer cells from another part of the body travel through the bloodstream and establish new tumors in the liver. This form of liver cancer is considerably more common than primary liver cancer. Cancers originating in organs like the colon, breast, lung, or pancreas frequently spread to the liver.
Identifying a Liver Mass and What to Do Next
The detection of a liver mass often begins incidentally, with many masses being identified during routine imaging tests like ultrasound, CT scans, or MRI performed for unrelated medical evaluations. While some individuals with liver masses may experience vague symptoms such as abdominal pain, unexplained weight loss, or yellowing of the skin (jaundice), these symptoms typically occur only when masses are large or the condition is advanced. Many small masses remain entirely asymptomatic.
Upon the discovery of a liver mass, the first step is to consult with a healthcare professional. Further diagnostic tests are usually necessary to determine the exact nature of the mass and guide subsequent medical decisions. These tests may include specialized blood work, such as liver function tests to assess liver health, and tumor markers, which are substances that can sometimes indicate the presence of certain cancers.
Advanced imaging techniques often provide more detailed views of the mass, helping to characterize its features. In some cases, particularly when malignancy is suspected, a liver biopsy may be performed. This procedure involves taking a small tissue sample from the mass for microscopic examination, which provides a definitive diagnosis. Professional medical evaluation is essential to accurately determine the nature of any liver mass and to establish the most effective course of action.