Overview of incidental liver lesions

Liver lesions are frequently found incidentally as a consequence of the widespread use of imaging tests. Incidental liver lesions can vary in size and number, and are usually benign.

Examples of liver lesions that may be detected incidentally include:

• malignant lesions—hepatocellular carcinoma, cholangiocarcinoma, liver metastases
• benign lesions—haemangioma, focal nodular hyperplasia, hepatocellular adenoma, liver cyst, regenerative nodules in the setting of cirrhosis, nodular regenerative hyperplasia.

History, examination and imaging characteristics are key to determining the nature of liver lesions. Liver lesions rarely cause pain, unless they are large or cause distension of the liver capsule. Severe, new onset pain may indicate a bleed or rupture of a liver lesion (usually one that is malignant).

In a young patient without known liver disease, an incidental liver lesion is most likely to be benign. Biopsy is rarely required.